Virtual Library

 x 
My Library Virtual Library FAQ

Start Your Search

K. Nagai



Author of

  • +

    MO03 - Thymic Malignancies (ID 123)

    • Event: WCLC 2013
    • Type: Mini Oral Abstract Session
    • Track: Medical Oncology
    • Presentations: 3
    • +

      MO03.01 - Outcome of surgical treatment for thymic epithelial tumors based on the nationwide retrospective database of 3033 patients in Japan (ID 2284)

      10:30 - 10:35  |  Author(s): K. Nagai

      • Abstract
      • Presentation
      • Slides

      Background
      Thymic epithelial tumor, consisting of thymoma, thymic carcinoma and thymic neuroendocrine carcinoma, is a relatively rare neoplasm, and there is not a satisfying consensus in the treatment strategy. Because of lack of TNM staging system and global consensus on pathological classification, global research in these research has been difficult. To participate in movement of establishing the global database, Japanese Association for research of the Thymus (JART) conducted the project of Japanese nation-wide database in 2012.

      Methods
      Patients undergoing surgical treatment during 20 years between 1991 and 2010 in Japan were collected from 32 institutes. 3182 patients were first enrolled, but after exclusion of cases with insufficient information, 3033 cases remained for analysis finally.

      Results
      1435 patients (44%) were male, and 1595 were female (not identified in 3 patients). The age at operation was 13 to 88 years (mean 57 years old). Pathological diagnosis was thymoma in 2505 patients (Type A: 203, Type AB: 710, Type B1: 599, Type B2: 669, Type B3: 329), thymic carcinoma in 381 patients (Squamous cell carcinoma: 223, neuroendocrine carcinomas 66), and unclassified or unknown in 147 patients. According to Masaoka staging system, 1063 patients were in stage I, 1084 were in stage II, 477 in stage III, 197 in stage IVA, 57 in stage IVB (undetermined in 155 patients). Complete resection was achieved in 2753 patients (92%), subtotal resection (mass reduction of more than 80%) in 157 patients (5%), partial resection including biopsy in 86 patients (unknown in 37 patients). 249 patients were alive with tumor. 316 patients were dead during the observation period, and 161 patients died from tumor. Among 2557 patients who underwent complete resection (R0), 269 patients (10.5%) had tumor recurrence. In the patients who underwent complete or subtotal resection, 10-year overall survival rate was 89% in thymoma, 56% in squamous cell carcinoma, 30% in non-squamous thymic carcinoma, 72% in well-differentiated neuroendocrine carcinoma and 29% in poorly-differentiated neuroendocrine carcinoma. According to Masaoka stage, 10-year overall survival rate was 94% in stage I, 93% in stage II, 74% in stage III, 59% in stage IVA and 44% in stage IVB. In thymoma patients who underwent complete resection, recurrence-free survival rate at 10 years was 96% in type A, 99% in type AB, 92% in type B1, 80% in type B2, 72% in type B3. By Cox’ proportional hazard model, involvement of the mediastinal pleura (p=0.01), involvement of the lung (p=0.01), pleural dissemination (p=0.0009), distant metastasis (p=0.01) and WHO histological subtype (p<0.0001) were found to be independent factors for tumor recurrence after complete resection, while nodal metastasis, intrapericardial dissemination, involvement of pericardium, pulmonary artery, SVC, brachiocephalic vein, aorta, or brachiocephalic artery were not.

      Conclusion
      Japanese nation-wide database revealed the oncological difference among thymoma, thymic carcinoma and thymic neuroendocrine carcinoma. In thymoma, involvement of pleura and lung, pleural dissemination, distant metastasis and WHO histological classification were significant factors of tumor recurrence. These results are supposed to contribute to clinical practice for tumor treatment as well as establishment of global TNM classification.

      Only Members that have purchased this event or have registered via an access code will be able to view this content. To view this presentation, please login, select "Add to Cart" and proceed to checkout. If you would like to become a member of IASLC, please click here.

      Only Active Members that have purchased this event or have registered via an access code will be able to view this content. To view this presentation, please login or select "Add to Cart" and proceed to checkout.

    • +

      MO03.02 - Surgical Outcome of Patients with Stage III Thymoma in the Japanese Nationwide Database (ID 2842)

      10:35 - 10:40  |  Author(s): K. Nagai

      • Abstract
      • Presentation
      • Slides

      Background
      Stage III thymoma has a variety characteristics in terms of involved organs, complex surgery and multimodal strategy, and a careful consideration is required in choices of treatments. Recently the Japanese Association for Research on the Thymus (JART) conducted a nationwide large cohort analysis for thymic epithelial tumors. The aim of this study is to clarify clinical characteristics and therapeutic outcome of patients who underwent surgical resection for stage III thymoma using this database.

      Methods
      Clinical data of 3,033 thymic epithelial tumor patients of 1991 to 2010 were collected rom 32 Japanese institutes. Medical information registered included patients’ characteristics, types of surgery, pathological diagnosis, perioperative therapy, and clinical outcomes were registered. In this study, stage III thymoma patients who underwent surgery were extracted from the database, and retrospectively analyzed for clinical characteristics and surgical outcome.

      Results
      A total of 340 records of patients were analyzed in this study, which comprised 186 males (54.7%) and 153 females (45.0%), 83 (24.4%) with myasthenia gravis, 42 (12.4%) with induction chemotherapy, 18 (5.3%) with preoperative radiotherapy, and 29 (8.5%) with adjuvant chemotherapies. WHO histologic types comprised 16 A (4.7%), 40 AB (11.8%), 47 B1 (13.8%), 118 B2 (34.7%) and 97 B3 (28.5%). Involved organs were lung in 209 (61.4%), pericardium in 167 (49.1%), chest wall in 7 (2.1%), phrenic nerve in 88 (25.9%) and great vessels in 134 (39.4%). Completeness of resection was R0 in 268 (78.8%), R1 in 35 (10.3%) and R2 in 20 (5.9%). Complications were observed in 85 (25.0%) including arterial fibrillation, phrenic nerve palsy, bleeding and crisis of myasthenia gravis, and 30-day mortality rate was 1.8% (6 cases). Tumor recurrence was experienced in 96 (28.2%), and 39 (11.5%) died during the observation. Overall and disease-free 10-year survival rates were 81.0% and 56.7%, respectively. Involved organs except for chest wall, completeness of resection or myasthenia gravis did not affect the survivals. Number of involved organs (1 vs. >2) and tumor length (<7cm vs. >7cm) affected disease-free survival but not overall survival. Among factors suggested to affect overall survival by univariate analyses such as male, surgical complication, WHO histologic type B1-3, chest wall invasion, induction treatments, and recurrence, independent adverse predictors were revealed by a multivariate analysis to be male (p=0.031, HR=2.47), induction chemotherapy (p=0.034, HR=2.39), postoperative complication (p=0.018, HR=2.41) and recurrence of disease (p=0.041, HR=2.15). Of 96 patients with recurrence, 47 patients who underwent salvage resection showed better prognosis than 49 patients who did not (p=0.009).

      Conclusion
      This nationwide registry study exhibited favorable surgical outcome in Japanese patients with stage III thymoma. Effectiveness of multimodal treatments need to be further investigated in prospective controlled trials.

      Only Members that have purchased this event or have registered via an access code will be able to view this content. To view this presentation, please login, select "Add to Cart" and proceed to checkout. If you would like to become a member of IASLC, please click here.

      Only Active Members that have purchased this event or have registered via an access code will be able to view this content. To view this presentation, please login or select "Add to Cart" and proceed to checkout.

    • +

      MO03.04 - Analysis of lymphatic metastases of thymic epithelial tumors on Japanese database (ID 3196)

      10:45 - 10:50  |  Author(s): K. Nagai

      • Abstract
      • Presentation
      • Slides

      Background
      Thymic epithelial tumors sometimes metastasize to lymph nodes (LNs). The frequency of lymph node metastasis, the pattern of node metastasis and the relationship between prognosis and node metastasis are still unclear.

      Methods
      We registered patients with thymic epithelial tumors who had undergone resection between 1991 and 2010 from 29 institutes in Japan by the Japanese Association for Research on the Thymus (JART). We investigated the collected data according to the site of lymphatic metastasis. Yamakawa-Masaoka's paper (Cancer 1991;68:1984–7.) tentatively classified the N factor to 3 groups: metastasis to anterior mediastinal lymph nodes around the thymus were defined as N1, metastasis to intrathoracic lymph nodes other than anterior mediastinal lymph nodes as N2, and metastasis to extrathoracic lymph nodes as N3.

      Results
      The rate of lymphatic metastasis in thymoma was 1.75% (44 cases of 2508). Most of metastatic nodes were located in anterior mediastinal lymph nodes (N1, 78%). There is a significant difference of overall survival between thymomas with LN metastasis and those without LN metastasis (p<0.0001, 10-year survival: 89.8% vs 63.6%). Thymomas with N1 metastasis showed a good prognosis than those with other node metastasis, although there is no significant relationship (5-year survival: 64.4% vs 52.5%). The rate of lymphatic metastasis in thymic carcinoma including thymic carcinoid was 22% (84 cases of 380). Most of metastatic nodes were located in anterior mediastinal lymph nodes (N1, 69%). There is a significant difference of overall survival between thymic carcinomas with LN metastasis and those without LN metastasis (p<0.0001, 10-year survival: 59.5% vs 18.4%). Thymic carcimomas with N1 metastasis showed good prognosis than those with other node metastases, although there was no significant relationship (5-year survival: 55.5% vs 27.5%).

      Conclusion
      The rate of lymphatic metastasis in thymoma and thymic carcinoma was 1.75% and 22%, respectively. Both tumors frequently metastasized to the anterior mediastinal nodes. There was a significant difference of overall survival between tumors with LN metastasis and without LN metastasis in both tumors. And both tumors with N1 metastasis showed good prognoses than those with other node metastases, although there was no significant relationship. We think that it may be reasonable to consider the anterior mediastinal lymph node group (N1) to be a primary lymph node of thymic epithelial tumor.

      Only Members that have purchased this event or have registered via an access code will be able to view this content. To view this presentation, please login, select "Add to Cart" and proceed to checkout. If you would like to become a member of IASLC, please click here.

      Only Active Members that have purchased this event or have registered via an access code will be able to view this content. To view this presentation, please login or select "Add to Cart" and proceed to checkout.

  • +

    MO04 - Lung Cancer Biology I (ID 86)

    • Event: WCLC 2013
    • Type: Mini Oral Abstract Session
    • Track: Biology
    • Presentations: 1
    • +

      MO04.10 - Identification of biological properties of intralymphatic tumor related to the development of lymph node metastasis in lung adenocarcinoma (ID 1724)

      17:10 - 17:15  |  Author(s): K. Nagai

      • Abstract
      • Presentation
      • Slides

      Background
      Intralymphatic tumors in the extratumoral area are considered to represent the preceding phase of lymph node (LN) metastasis. The aim of this study was to clarify the biological properties of intralymphatic tumors susceptible to the development of LN metastasis, with special reference to the expression of cancer initiating/stem cell (CIC/CSC) markers in cancer cells and the number of infiltrating stromal cells.

      Methods
      A total of 2087 consecutive adenocarcinoma patients underwent complete resections and systematic LN dissections between May 1998 and December 2012 were identified. Among these cases, we selected those that had been diagnosed as having lymphatic permeation in the extratumoral area (n = 107). We examined the expression levels of CIC/CSC related markers including ALDH1, OCT4, NANOG, SOX2 and Caveolin-1 in the intralymphatic and primary tumor cells to evaluate their relationship to LN metastasis. The number of infiltrating stromal cells expressing CD34, α-smooth muscle actin, and CD204 were also evaluated. Moreover, we measured E-cadherin expression to identify a correlation between CIC/CSC related molecules and epithelial - mesenchymal transition (EMT) process.

      Results
      Intrathoracic LN metastases were detected in specimens from 86 patients (80%). Among the intralymphatic tissues, low ALDH1 expression in cancer cells, high SOX2 expression in cancer cells, and a high number of CD204(+) macrophages were independent predictive factors for LN metastasis (odds ratio [95%CI] = 3.25 [1.11 – 9.82], P = 0.031 for ALDH1; 4.09 [1.38 – 13.4], P = 0.011 for SOX2; and 3.45 [1.16 – 11.4], P = 0.026 for CD204(+) macrophages). However, in the primary tumors, only a high SOX2 expression level in the cancer cells within the primary tumor was significantly correlated with LN metastasis (p=0.008); ALDH1 expression in the cancer cells and the number of CD204(+) macrophages were not correlated with LN metastasis (P = 0.230 and P = 0.088, respectively). Among these factors, only low ALDH1 expression in intralymphatic cancer cells was significantly correlated with the farther spreading of LN metastasis (mediastinal LN, pN2) (P = 0.046) and higher metastatic LN ratio (metastatic/resected) (P = 0.028). Intralymphatic cancer cells expressing low ALDH1 levels exhibited lower E-cadherin expression levels than cancer cells with high levels of ALDH1 expression (P = 0.015). The expressions of other CIC/CSC related markers, including OCT4, NANOG, SOX2, and Caveolin-1, were not correlated with the E-cadherin expression.

      Conclusion
      Intralymphatic cancer cells expressing low levels of ALDH1 and infiltrating macrophages expressing CD204 have a critical impact on LN metastasis. Especially, intralymphatic cancer cells expressing low levels of ALDH1 might acquire a metastatic aggressiveness by the EMT process. Our study highlighted the significance of evaluating the biological properties of intralymphatic tumors for tumor metastasis and suggested the possibility of usefulness as a new molecular target, especially as an adjuvant therapy.

      Only Members that have purchased this event or have registered via an access code will be able to view this content. To view this presentation, please login, select "Add to Cart" and proceed to checkout. If you would like to become a member of IASLC, please click here.

      Only Active Members that have purchased this event or have registered via an access code will be able to view this content. To view this presentation, please login or select "Add to Cart" and proceed to checkout.

  • +

    MO13 - SCLC I (ID 118)

    • Event: WCLC 2013
    • Type: Mini Oral Abstract Session
    • Track: Medical Oncology
    • Presentations: 1
    • +

      MO13.08 - A pilot study of adjuvant chemotherapy with irinotecan and cisplatin for completely resected high grade pulmonary neuroendocrine carcinona (Large cell neuroendocrine carcinoma and small cell lung cancer) (ID 1562)

      11:15 - 11:20  |  Author(s): K. Nagai

      • Abstract
      • Presentation
      • Slides

      Background
      Large cell neuroendocrine carcinoma (LCNEC) and small cell lung cancer (SCLC) are recognized as high grade neuroendocrine carcinoma (HGNEC) of the lung. In patients with completely resected HGNEC, platinum-based adjuvant chemotherapy may be considered. However, the optimum chemotherapy regimen has not been determined. We conducted a multicenter single-arm phase II trial to evaluate irinotecan and cisplatin in postoperative adjuvant chemotherapy for HGNEC patients.

      Methods
      Patients with completely resected stage I- IIIA HGNEC received 4 cycles of irinotecan (60 mg/m[2], day 1, 8, 15) plus cisplatin (60 mg/m[2], day 1). This regimen was repeated every 4 weeks. Other eligibility criteria included ECOG PS 0–1, age 20, and <75 years old, adequate organ function, and no prior chemotherapy or radiotherapy. Patients with UGT1A1 polymorphisms (homozygous for *6 or *28, or simultaneously heterozygous *6 and *28), associated with irinotecan-related severe toxicity, were excluded. The primary endpoint was the rate of completion of chemotherapy (defined as underwent 3 or 4 cycles), and secondary endpoints were 3-year relapse free survival (RFS), rate of 3-year survival and toxicities.

      Results
      Forty patients were enrolled between September 2007 and April 2010. Patients’ characteristics were as follows: median age (range) 65 (45-73) years; male 85%; ECOG-PS 1 60%; LCNEC 57% and SCLC 43%; stage IA/IB/IIB/IIIA 32/35/8/5%; 95% received lobectomy. The rate of completion of chemotherapy was 83% (90% C.I.; 71-90%). The rate of overall survival at 3 years was estimated at 81%, and of RFS at 3 years was 74%. The rates of overall survival and RFS at 3 years were 86% and 74% among 23 LCNEC patients, and 74%, 76% among 17 SCLC patients, respectively. Nineteen patients (48%) experienced grade 3 or 4 neutrophils, but only five patients (13%) developed febrile neutropenia. Two patients (5%) developed grade 3 diarrhea, and 4 patients (10%) had grade 3 nausea. No treatment related deaths were observed in this study. All 40 specimens were also diagnosed as HGNEC at pathological central review among 7 pathologists. There were two specimens that showed the difference in between institutional diagnosis and central pathological diagnosis.

      Conclusion
      The combination of irinotecan and cisplatin as postoperative adjuvant chemotherapy was feasible and possibly efficacious for resected HGNEC.In Japan, a randomized phase III trial is ongoing to evaluate adjuvant chemotherapy of irinotecan and cisplatin, compared with etoposide and cisplatin, for completely resected HGNEC.

      Only Members that have purchased this event or have registered via an access code will be able to view this content. To view this presentation, please login, select "Add to Cart" and proceed to checkout. If you would like to become a member of IASLC, please click here.

      Only Active Members that have purchased this event or have registered via an access code will be able to view this content. To view this presentation, please login or select "Add to Cart" and proceed to checkout.

  • +

    MO26 - Anatomical Pathology II (ID 129)

    • Event: WCLC 2013
    • Type: Mini Oral Abstract Session
    • Track: Pathology
    • Presentations: 2
    • +

      MO26.09 - Prognostic impact of CD204-positive macrophages in lung squamous cell carcinoma (ID 2023)

      11:15 - 11:20  |  Author(s): K. Nagai

      • Abstract
      • Presentation
      • Slides

      Background
      Stromal cells, including macrophages, lymphocytes and fibroblasts, are known to interact with cancer cells and to produce a specific microenvironment capable of influencing tumor progression. Tumor-associated macrophages (TAMs) are recruited into cancer-induced stroma and produce a specific microenvironment for cancer progression. CD204 positive TAMs are reportedly related to tumor progression and clinical outcome in some tumors. The aim of this study was to clarify the correlation between CD204 positive TAMs and the clinicopathological features of lung squamous cell carcinoma.

      Methods
      We investigated the relationships between the numbers of CD204 positive TAMs and clinicopathological factors, microvessel density (MVD), and the numbers of Foxp3 positive lymphocytes in 208 consecutively resected cases. We also examined the relationships between the numbers of CD204 positive TAMs and the expression levels of cytokines involved in the migration and differentiation of CD204 positive TAMs.

      Results
      A high number of CD204 positive TAMs in the stroma was significantly correlated with an advanced p-stage, T factor, N factor, and the presence of vascular and pleural invasion. A high number of CD204 positive TAMs in the stroma was also a significant prognostic factor for all p-stages and p-stage I. Moreover, the numbers of CD204 positive TAMs were correlated with the MVD and the numbers of Foxp3 positive lymphocytes. A high number of CD204 positive TAMs was strongly correlated with the tissue expression level of MCP-1. CD204 positive TAMs were shown to be significant independent prognostic factors in a multivariate analysis.

      Conclusion
      CD204 positive TAMs were an independent prognostic factor in lung squamous cell carcinoma. CD204 positive TAMs, along with other tumor-promoting stromal cells such as regulatory T cells and endothelial cells, may create tumor-promoting microenvironments.

      Only Members that have purchased this event or have registered via an access code will be able to view this content. To view this presentation, please login, select "Add to Cart" and proceed to checkout. If you would like to become a member of IASLC, please click here.

      Only Active Members that have purchased this event or have registered via an access code will be able to view this content. To view this presentation, please login or select "Add to Cart" and proceed to checkout.

    • +

      MO26.12 - Prognostic Impact of Microscopic Vessel Invasion and Visceral Pleural Invasion in Non-small Cell Lung Cancer (ID 2480)

      11:35 - 11:40  |  Author(s): K. Nagai

      • Abstract
      • Presentation
      • Slides

      Background
      In non-small cell lung cancer (NSCLC), visceral pleural invasion (VPI) is incorporated as a staging factor in the current TNM classification. Microscopic vessel invasion (MVI: defined collectively as histological blood vessel invasion and lymphatic permeation) has been reported to be a strong independent predictor of poor prognosis, but it has not been incorporated in the TNM classification. We assessed the prognostic significance of MVI as well as VPI.

      Methods
      Between August 1992 to December 2009, 2657 consecutive patients with pathological T1-4N0-2M0 NSCLC underwent complete resection at our institution. We analyzed the prognostic significance of MVI for recurrence in addition to the conventional prognostic factors. The recurrence-free proportion was estimated using the Kaplan-Meier method and differences were analyzed by the log-rank test. Cox regression analyses were used to identify independent risk factors for recurrence.

      Results
      The 5-year recurrence-free proportion for patients with or without MVI was 52.6% and 87.5%, respectively (p < 0.001). On multivariate analysis, MVI, similarly to VPI, was found to be an independently significant predictor of recurrence (HR 2.78). In 1601 patients with pathological stage I disease without adjuvant chemotherapy, MVI and VPI were the two strongest independent predictors of recurrence on multivariate analysis (HR 2.74 and 1.84, respectively). Evident and significant separation of the recurrence-free proportion curves among the following 3 groups according to the number of the two risk factors (VPI and MVI) was observed; both VPI and MVI absent (0), either VPI or MVI present (1), and both VPI and MVI present (2). We compared the recurrence-free proportion of patients stratified by tumor size and the number of the risk factors (0/1/2) (Table 1). The groups of small tumor size without PL and MVI showed the best recurrence-free proportions (T1a_0, T1b_0, and T2a_0). The T1a_1, T1b_1, and T2a_1 subgroups showed poorer outcomes which were comparable with the T2b_0 subgroup. The groups with both PL and MVI, even in small tumor size groups, resulted in poor outcomes equivalent to that of T3_0/1 groups. The T3_2 group showed the poorest outcome equivalent to the T4 group.

      Conclusion
      This study demonstrated that MVI was a significantly independent risk factor for recurrence in resected T1-4N0-2M0 NSCLC patients. We propose the T-classification of tumors with either MVI or VPI (1) should be upgraded to the next T level and that with both MVI and VPI (2) to the second T level (Table 1).

      Table 1. Incorporation of PL and MVI into T classification
      Current (7th) T Classification Tumor Size (cm) No. of VPI and MVI Risk Factors Recurrence-free Proportion at 5 Years (%) OurProposalT
      T1a ≤ 2 0 92.2 T1
      ≤ 2 1 72.2 T2
      ≤ 2 2 58.2 T3
      T1b > 2, ≤ 3 0 89.6 T1
      > 2, ≤ 3 1 64.8 T2
      > 2, ≤ 3 2 50.9 T3
      T2a > 3, ≤ 5 0 87.8 T1
      > 3, ≤ 5 1 61.9 T2
      > 3, ≤ 5 2 44.8 T3
      T2b > 5, ≤ 7 0 75.9 T2
      > 5, ≤ 7 1 49.4 T3
      > 5, ≤ 7 2 47.5 T3
      T3 > 7 0 58.2 T3
      > 7 1 50.6 T3
      > 7 2 38.8 T4

      Only Members that have purchased this event or have registered via an access code will be able to view this content. To view this presentation, please login, select "Add to Cart" and proceed to checkout. If you would like to become a member of IASLC, please click here.

      Only Active Members that have purchased this event or have registered via an access code will be able to view this content. To view this presentation, please login or select "Add to Cart" and proceed to checkout.

  • +

    O09 - General Thoracic Surgery (ID 100)

    • Event: WCLC 2013
    • Type: Oral Abstract Session
    • Track: Surgery
    • Presentations: 1
    • +

      O09.05 - Intraoperative autostapling cartridge lavage cytology in surgical resection of pulmonary malignant tumors - possible role in preventing local failure (ID 2543)

      17:00 - 17:10  |  Author(s): K. Nagai

      • Abstract
      • Presentation
      • Slides

      Background
      Limited resection of primary lung cancer or sublobar resection of pulmonary metastatic tumor can result in cut-end recurrence. It is important to confirm the absence of tumor cells at the cut-end. Since 2004, all autostapling cartridges used for wedge or segmental resection of pulmonary malignancies are washed with 50 ml saline. Washing saline is centrifuged and the sediment is stained using Papanicolaou’s method and examined for cancer cells during surgery to confirm negative margin. The aim of this study is to evaluate the efficacy of the intraoperative autostapling cartridge lavage cytology in preventing surgical cut-end recurrence.

      Methods
      The intraoperative cytology analysis was performed in 271 patients undergoing wedge or segmental resection for 319 lesions including primary lung cancers and pulmonary metastatic tumors between April 2004 and April 2010. We retrospectively reviewed the clinicopathologic features of patients with positive cytology results and those who developed recurrence at the surgical margins.

      Results
      The median age of the 271 patients at surgery was 67 years (range: 31−92 years). The median size of the 319 lesions was 1.4 cm (range: 0.4−3.5 cm), and there were 149 primary lung cancers and 170 pulmonary metastatic tumors (primary site: 116 colorectal and 54 others). Twenty-two lesions (7%) showed positive cytology results (11 primary and 11 metastatic). In primary lung cancers, tumor size (≧ 21 mm, p = 0.02), moderate to poor differentiation (p ＜ 0.01), vascular invasion or lymphatic permeation (p ＜ 0.01), and visceral pleural invasion (p ＜ 0.01) were significant predictors of a positive result. In contrast, there were no significant predictors in pulmonary metastatic tumors. The cut-ends of the 19 lesions among the 22 positive cytology margin lesions were additionally resected, but those of the remaining 3 lesions were not because of impaired respiratory function. With the median follow-up period of 42 months, surgical cut-end recurrence occurred in 2 of the 19 lesions for which additional resection had been performed (11%, 1 primary and 1 metastatic). Of the 3 lesions for which additional resection was impossible, cut-end recurrence developed in 2 (67%, 1 primary and 1 metastatic). Among the 297 lesions showing negative cytology result, cut-end recurrence occurred in 5 (2%, 4 primary and 1 metastatic).

      Conclusion
      Intraoperative autostapling cartridge lavage cytology in sublobar resection for primary or metastatic lung tumor may be useful in preventing surgical cut-end recurrence.

      Only Members that have purchased this event or have registered via an access code will be able to view this content. To view this presentation, please login, select "Add to Cart" and proceed to checkout. If you would like to become a member of IASLC, please click here.

      Only Active Members that have purchased this event or have registered via an access code will be able to view this content. To view this presentation, please login or select "Add to Cart" and proceed to checkout.

  • +

    O13 - Limited Resections (ID 101)

    • Event: WCLC 2013
    • Type: Oral Abstract Session
    • Track: Surgery
    • Presentations: 1
    • +

      O13.01 - Limited Resection Trial for Pulmonary Ground-glass Opacity Nodules: Case Selection Based on High Resolution Computed Tomography: Interim Results (ID 1233)

      10:30 - 10:40  |  Author(s): K. Nagai

      • Abstract
      • Presentation
      • Slides

      Background
      Japanese researchers have reported good correlation between radiologic and pathologic findings in early lung adenocarcinomas. For negative margin confirmation, we found a technique using lavage and cytological examination. The objective of this study is to confirm limited resection efficacy as radical surgery in patients with high-resolution (HR) computed tomography (CT) indicated minimally invasive lung cancer, and to confirm intraoperative cytology as a negative margin indicator and reliable margin non-recurrence predictor.

      Methods
      Enrollment required patients with a tumor ≤ 2 cm in diameter, diagnosed or suspected as a clinical T1N0M0 carcinoma in the lung periphery based on a CT scan. They had to have a HRCT scan indicating a sub-solid nodule with tumor disappearance ratio; TDR ≥ 0.5. (TDR = 1- DM/DL; DM: maximum tumor diameter on mediastinal settings, DL: maximum tumor diameter on lung settings). Patients with a malignancy history within the past 5 years or those unfit for lobectomy and systematic lymph node dissection were excluded. We performed a wedge or segmental resection. The used stapling cartridges were washed with 50 ml saline. Washing saline was centrifuged and sediment stained using Papanicolaou’s method and examined for cancer cells. If cytology was cancer positive, additional margin was resected, and cytologic examination repeated. If the second exam was positive, a routine lobectomy and systematic lymph node dissection was performed. Patients are followed up every 6 months by chest CT for the first 3 years, and annually thereafter for at least 5 years. The initial endpoint was 5-year local recurrence free survival rate, but we are now looking at 10-year rate.

      Results
      This prospective study started in November 2003, and 101 patients were enrolled as of November 2009. This was 4.5% of all resected lung cancer patients during this period, and 99 of them were eligible for analysis. There were 39 men and 60 women, aged 30-75, with an average 62 years. Tumor sizes ranged from 7 to 20 mm on high-resolution CT, averaging 15 mm. There were 11 Noguchi type A tumors, 54 type B tumors, 26 type C tumors, one type D tumor, one malignant lymphoma, one atypical adenomatous hyperplasia, one atypical cuboidal cell hyperplasia, one alveolar hyperplasia, and 3 inflammatory fibroses. All cancers showed no vessel invasion. Although no positive cytology results were obtained, pathologically positive margin was reported after surgery in one type C patient. He later underwent a routine lobectomy and systematic lymph node dissection. There was no clear correlation between tumor size, TDR, and Noguchi subtype. No mortality occurred, but one patient developed postoperative pneumothorax and pneumonia, and another hemorrhagic gastric ulcer. With a median follow-up period of 69 months, there have been no recurrences.

      Conclusion
      So far, HRCT scans appear to predict non- or minimally invasive GGO lung cancers with high reliability, warranting limited resection as curative surgery in this cohort. Intraoperative cytology reliably indicated negative margins and seems to predict freedom from local recurrence.

      Only Members that have purchased this event or have registered via an access code will be able to view this content. To view this presentation, please login, select "Add to Cart" and proceed to checkout. If you would like to become a member of IASLC, please click here.

      Only Active Members that have purchased this event or have registered via an access code will be able to view this content. To view this presentation, please login or select "Add to Cart" and proceed to checkout.

  • +

    O29 - Cancer Control & Epidemiology IV (ID 132)

    • Event: WCLC 2013
    • Type: Oral Abstract Session
    • Track: Prevention & Epidemiology
    • Presentations: 1
    • +

      O29.07 - The clinical outcome of non-small cell lung cancer patients with adjacent lobe invasion: proposal for optimal classification according to the status of interlobar pleura in invasion point (ID 1168)

      11:35 - 11:45  |  Author(s): K. Nagai

      • Abstract
      • Presentation
      • Slides

      Background
      In the 7th TNM classification, non-small cell lung cancer (NSCLC) with adjacent lobe invasion (ALI) is classified as T2a regardless of whether across the complete or incomplete fissure. However, no validation analysis has been conducted on this classification. The aim of this study was to analyze the survival of NSCLC patients with ALI with emphasis on the interlobar fissure status at invasion point.

      Methods
      We retrospectively evaluated 2097 consecutive patients with surgically resected NSCLC from 1993 through 2006. Of these, 90 (4.3%) patients had tumors with ALI. Interlobar fissure status of tumors with ALI was examined by using elastic stain. We classified ALI into 2 types: direct ALI beyond incomplete interlobar fissure (no visceral pleurae separating two lobes; ALI-D) and ALI across complete fissure (two lobes separated by 2 visceral pleurae; ALI-A), and compared the clinicopathological features and survival between the groups.

      Results
      The patients with ALI without any other criteria higher than T2b category (n = 60) demonstrated intermediate survival between T2a and T2b tumors (5-year overall survival [OS]: T2a, 61.0%; ALI, 59.6%; T2b, 49.2%). Distinct survival difference was observed between the patients with ALI-A (n = 46) and ALI-D (n = 14) (5-year OS: ALI-D, 85.7%; ALI-A, 52.0%; p = 0.01). The survival of patients with ALI-A was not statistically different from that of patients with T2b tumors, regardless of tumor size (p = 0.85). Conversely, the survival of the patients with ALI-D did not statistically differ from those with T1a or T1b tumors (p = 0.77 and 0.42, respectively).Figure 1Figure 2

      Conclusion
      Interlobar fissure status clearly affected survival of the patients with ALI. ALI should be examined by elastic stains and only ALI-A should be classified as true ALI. We propose that ALI-A tumors ≤ 5 cm should be assigned to T2b but ALI-D tumors do not require adjustment of T descriptor.

      Only Members that have purchased this event or have registered via an access code will be able to view this content. To view this presentation, please login, select "Add to Cart" and proceed to checkout. If you would like to become a member of IASLC, please click here.

      Only Active Members that have purchased this event or have registered via an access code will be able to view this content. To view this presentation, please login or select "Add to Cart" and proceed to checkout.

  • +

    P1.10 - Poster Session 1 - Chemotherapy (ID 204)

    • Event: WCLC 2013
    • Type: Poster Session
    • Track: Medical Oncology
    • Presentations: 1
    • +

      P1.10-011 - Clinicopathological analysis of long-term (more than 2 years) progression-free survivors treated with epidermal growth factor receptor - tyrosine kinase inhibitors (EGFR-TKIs) in patients with EGFR mutation-positive non-small cell lung cancer (ID 753)

      09:30 - 09:30  |  Author(s): K. Nagai

      • Abstract

      Background
      Presence of activating EGFR mutations is known to be predictive of a favorable response to treatment with EGFR-TKIs in non-small cell lung cancer (NSCLC) patients. Indeed, in clinical practice, EGFR-TKI treatment in patient with NSCLC harboring EGFR mutations sometimes yields a progression-free survival (PFS) of more than 2 years. The aim of this study was to evaluate the clinicopathological features of patients showing long-term (in the context of this study, more than 2 years) PFS.

      Methods
      Data of 194 consecutive patients with EGFR mutation-positive NSCLC treated with EGFR-TKIs between May 2003 and May 2011 were reviewed. PFS was measured from the date of start of EGFR-TKI treatment to the date of documentation of disease progression, death or the last follow-up.

      Results
      The characteristics of the 194 patients were as follows, male/female: 70/124; median age: 65 years (range 36-88); PS 0-1/2-3: 170/24; adenocarcinoma/non-adenocarcinoma: 189/5; advanced/recurrent: 104/90; EGFR-TKI 1st line/2nd or 3rd line: 120/74; gefitinib/erlotinib: 170/24; Exon 19 deletion/L858R/other mutations: 98/86/10. The median progression-free survival was 9.7 months. Of the 194 patients, 32 (16%) showed long-term progression-free survival. The results of univariate analyses revealed significant associations between the PFS and the PS and site of EGFR mutation. The EGFR-TKI treatment line (1st line/2nd or 3rd line) and specific EGFR TKI used (gefitinib/erlotinib) exerted no significant influence on the PFS. Multivariate analysis with a Cox proportional hazards model identified PS0-1 and Exon 19 deletion as independent favorable prognostic factors for PFS. The median PFS in patients with PS 0-1 and Exon 19 deletion (n=88) was 13.2 months, and 20 of the 88 patients (23%) showed long-term progression-free survival.

      Conclusion
      Patients with good PS and Exon 19 deletion appear to have a higher likelihood of showing long-term progression-free survival. Therefore, the site of EGFR mutation, in addition to the PS, may be useful as a stratification factor in future clinical trials.

  • +

    P1.12 - Poster Session 1 - NSCLC Early Stage (ID 203)

    • Event: WCLC 2013
    • Type: Poster Session
    • Track: Medical Oncology
    • Presentations: 1
    • +

      P1.12-007 - The Predictors of Early Recurrence in Patients with Completely Resected p-stage I Non-Small Cell Lung Cancer (ID 1256)

      09:30 - 09:30  |  Author(s): K. Nagai

      • Abstract

      Background
      The objective of this study was to identify the risk factors for early (within 2 years after surgery) recurrence in patients with completely resected pathological stage I (p-stage I) non-small cell lung cancer (NSCLC).

      Methods
      We reviewed retrospectively 864 consecutive patients with p-stage I NSCLC who underwent complete resection between 1992 and 2012 at our institution. The correlation between clinicopathologic factors (sex, age, preoperative CEA level, tumor laterality, primary lobe, smoking history, histological type, histological differentiation, p-T status, lymphatic permeation, vascular invasion, pleural invasion) and early recurrence was evaluated using chi-square test and multivariate analysis.

      Results
      There were 498 men and 366 women, with an average age of 67 years. (range: 33-87). The median follow up period was 78 months. Histologically, 659 patients had adenocarcinomas, 189 squamous cell carcinomas, and 16 other types. T status was 1a in 230 patients, 1b in 274, and 2a in 360. Vascular invasion was observed in 326 patients, and lymphatic permeation in 169. Recurrence developed in 208 patients (24.1%), and 64 (7.4%) of them developed within 2 years after surgery. By multivariate analysis, vascular invasion (hazard ratio 3.441, 95% confidence interval 1.892-6.428) and moderate to poor differentiation (hazard ratio 3.252, 95% confidence interval 1.242-8.512) were shown to be independently significant risk factors for early recurrence. In patients with vascular invasion, distant failure occurred significantly more frequently than locoregional recurrence. The early recurrences were distant failure in 46 patients (72%). Of the 18 patients with locoregional recurrence only, 13 had malignant pleural effusion or pleural dissemination.

      Conclusion
      Moderate to poor differentiation and vascular invasion were the significant predictors of early recurrence within 2 years after complete resection of p-stage I NSCLC. More than 90% of the early recurrences were disseminated diseases. Therefore, adjuvant chemotherapy after complete resection may be beneficial for p-stage I NSCLC patients with vascular invasion or moderately to poorly differentiated tumors.

  • +

    P1.19 - Poster Session 1 - Imaging (ID 179)

    • Event: WCLC 2013
    • Type: Poster Session
    • Track: Imaging, Staging & Screening
    • Presentations: 1
    • +

      P1.19-005 - Computer-aided lung nodule analysis focused on ground glass opacity and consolidation on thin-section computed tomography. (ID 1447)

      09:30 - 09:30  |  Author(s): K. Nagai

      • Abstract

      Background
      Ground-glass opacity (GGO) component in a nodule on thin-section computed tomography (TSCT) often corresponds to a lepidic growth pattern of adenocarcinoma. In contrast, solid attenuation or consolidation on TSCT corresponds to invasive components. Many researchers reported consolidation tumor ratio (CTR; defined as the ratio of the size of solid attenuation to the maximum tumor dimension) was a reliable parameter in predicting tumor invasiveness. However, it has been pointed out that inter-/intra-observer variability in CTR measurement is a major problem in precise and reproducible evaluation of tumor characteristics. The aim of this study was to determine the optimal CT settings to reproducibly diagnose GGO and consolidation areas on TSCT by using an imaging software.

      Methods
      We reviewed preoperative TSCT images of the patients undergoing surgical resection for T1 lung adenocarcinoma in our institution between 2005 and 2009. The TSCT images were obtained without contrast enhancement and reconstructed in 1.0 or 2 mm thickness, using several CT systems. The imaging software colored GGO areas with cut-off CT levels of -800, -700 and -600 HU. Consolidation areas were colored with cut-off CT levels of -300, -200 and -100 HU. These GGO/consolidations identified by the software were compared with those visually determined by the consensus of the 4 authors (EY, KA, YM, HO). The 4 authors scored the correspondence between visual evaluation and software identification according to the cut-off levels. The scores were summarized to determine the optimal cut-off CT levels.

      Results
      We have reviewed 20 patients so far. Figure 1 shows a TSCT image and software-yielded image showing good correspondence with each other of GGO and consolidation areas. The best score was obtained when the cut-off level was -700 HU for GGO and -200 HU for consolidation. Figure1. Figure 1

      Conclusion
      Although based on a small cohort, we found optimal cut-off CT levels to identify GGO and consolidation areas using an imaging software. We need to analyze more cases, but this image analysis method is promising in determining CTR reproducibly.

  • +

    P1.20 - Poster Session 1 - Early Detection and Screening (ID 172)

    • Event: WCLC 2013
    • Type: Poster Session
    • Track: Imaging, Staging & Screening
    • Presentations: 1
    • +

      P1.20-003 - Lung Cancers Detected Using Low-dose CT Screening: Results of an Eight-year Observational Study (ID 1779)

      09:30 - 09:30  |  Author(s): K. Nagai

      • Abstract

      Background
      To evaluate lung cancers detected using low-dose CT screening between February 2004 and March 2012.

      Methods
      The number of screenees analyzed in the observational study was 12,116. Screenees were classified into three groups based on their smoking index (SI): SI ≥ 600, SI < 600, and never-smokers. Overall, 147 lung cancers in 132 cases treated at the National Cancer Center Hospital and the National Cancer Center Hospital East were evaluated according to the smoking index. Adenocarcinomas were evaluated based on the following classification: group A (adenocarcinoma in situ and minimally invasive adenocarcinoma), and group B (invasive adenocarcinoma). Statistical analyses were performed using the chi-square test.

      Results
      The ages of the patients with lung cancer ranged between 42 and 85 years (mean, 61 years). Thirty-two of the 2989 male screenees (1.48%) and 2 of the 149 female screenees (1.34%) in the SI≥600 group, 22 of the 2989 male screenees (0.74%) and 10 of the 796 female screenees (1.26%) in the SI<600 group, and 16 of the 2148 male screenees (0.74%) and 50 of the 3878 female screenees (1.29%) in the never-smoker group were diagnosed as having lung cancer. Among the 147 lung cancers, 8 lesions (5.4%) did not present as nodules and instead appeared as a partial thickening of the bulla wall, a funicular-like shadow, a pneumonia-like shadow, etc. Among the remaining 139 lung cancers, 35 lesions (25.2%) presented as pure ground-glass nodules (GGNs), 64 lesions (46%) presented as part-solid nodules, and 40 lesions (28.8%) presented as solid nodules. The histology of the lung cancers was adenocarcinoma in 132 cases (89.8%), squamous cell carcinoma in 8 cases (5.4%), small cell carcinoma in 3 cases (2%), adenosquamous carcinoma in 1 case (0.7%), carcinoid tumor in 2 cases (1.4%), and NSCLC in 1 case (0.7%). The disease stages were as follows: IA, 127 (86.4%); IB, 11 (7.5%); IIA, 2 (1.4%); IIB, 1 (0.7%); IIIA, 3 (2.0%); and IIB, 3 (2.0%). Among the 147 cancers, the number of incident cases was 8 in the SI≥600 group (median follow-up period, 3.1 years), 3 in the SI<600 group (median follow-up period, 2.9 years), and none in the never-smoker group (median follow-up period, 3.0 years). Lung cancer cases in smokers (including ex-smokers) occurred predominantly in men (male, 54; female, 12), while lung cancer cases in never-smokers occurred predominantly in women (female, 50; male, 16) (P < 0.0001). The number of adenocarcinomas in smokers (including ex-smokers) was 29 in group A and 24 in group B, while the number of adenocarcinomas in never-smokers was 42 in group A and 23 in group B (P = 0.274). In the never-smoker group, the number of adenocarcinomas in men was 7 in group A and 9 in group B, while the number of adenocarcinomas in women was 35 in group A and 14 in group B (P < 0.05).

      Conclusion
      The number of invasive adenocarcinomas was not statistically different between smokers (including ex-smokers) and never-smokers. Never-smokers should also be a target population of CT lung cancer screening. Adenocarcinoma may be overdiagnosed among female never-smokers.

  • +

    P3.06 - Poster Session 3 - Prognostic and Predictive Biomarkers (ID 178)

    • Event: WCLC 2013
    • Type: Poster Session
    • Track: Biology
    • Presentations: 1
    • +

      P3.06-050 - Characteristic Immunophenotype of Solid Subtype Component<br /> in Lung Adenocarcinoma (ID 3289)

      09:30 - 09:30  |  Author(s): K. Nagai

      • Abstract

      Background
      Lung adenocarcinomas represent a morphologically heterogeneous tumor composed of an admixture of different histologic subtypes (lepidic, papillary, acinar, and solid subtype). The presence of a solid subtype component is reported to be associated with a poorer prognosis. The aim of this study was to evaluate the characteristic immunophenotype of the solid subtype component compared with the immunophenotypes of other components.

      Methods
      We analyzed the clinicopathological characteristics of stage I adenocarcinoma patients with predominant solid subtype disease. Furthermore, we immunostained adenocarcinomas with predominant lepidic, papillary, acinar, and solid subtype components (n = 23 each) for 10 molecular markers of tumor invasiveness and scored the results.

      Results
      Patients showing predominance of the solid subtype component (solid subtype adenocarcinoma) had a poorer prognosis than those showing predominance of the lepidic, papillary, or acinar component. Lymphovascular invasion was more often detected in solid subtype tumors than in others. The solid subtype component showed a significantly stronger staining intensity of laminin-5 expression than the lepidic, papillary, and acinar components (P\\0.001, P\\0.001, and P = 0.016, respectively). The fibronectin and vimentin expression levels were also significantly higher in the solid subtype component than in other components. This immunostaining character was validated by using mixed-subtype adenocarcinomas containing all four components in the same tumor.

      Conclusion
      This study concluded that the solid subtype component in lung adenocarcinomas exhibit the invasive immunophenotype, including increased laminin-5 expression, compared with the other components, which may be associated with a poorer prognosis.

  • +

    P3.07 - Poster Session 3 - Surgery (ID 193)

    • Event: WCLC 2013
    • Type: Poster Session
    • Track: Surgery
    • Presentations: 2
    • +

      P3.07-014 - Post-recurrence survival of surgically resected non-small cell lung cancer patients in the era of EGFR-TKI (ID 1450)

      09:30 - 09:30  |  Author(s): K. Nagai

      • Abstract

      Background
      Although surgical resection is the standard treatment of choice for early stage non-mall-cell lung cancer (NSCLC), not a small percentage of patients recur even after complete resection, and post-recurrence survival (PRS) is dismal. Since epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor (TKI) was approved for patients with advanced or recurrent NSCLC in 2002 in Japan, the number of long-term survivors after recurrence seems to be increasing. There have been few reports on post-recurrence survival in the era of EGFR-TKI. In the present study, we analyzed PRS in patients with completely resected NSCLC after EGFR-TKI was introduced in clinical practice.

      Methods
      From 1992 to 2010, 3058 NSCLC patients underwent complete resection in our hospital. Among them, 938 (31%) patients recurred. Of them, 503 patients, who recurred in 2002 or later and received anticancerous treatment, were the subject of this analysis. We retrospectively analyzed their clinicopathological characteristics, PRS, and identified favorable prognostic factors.

      Results
      The median age at recurrence was 68 years (range: 23-91), and 332 (58%) of them were men. There were 347 (69%) adenocarcinoma patients and 101 (20%) squamous cell carcinoma patients. The pathological stages of the primary cancers were I in 183 patients (36%), II in 120 (24%), and III in 200 (40%), respectively. Fifty-six patients (11%) underwent reoperation for recurrent lesions. Of the 216 patients whose EGFR mutation was examined, mutation was positive in 97 patients (45%). The median period of follow-up after recurrence was 49 months (range: 7-124). The overall 3- and 5-year PRS were 27% and 16%, respectively and their median PRS length was 19 months. The multivariate analysis revealed that adenocarcinoma, negative pleural invasion, locoregional recurrence, surgical resection of recurrent lesion, positive EGFR mutation were independent favorable prognostic factors. The 3-year PRS rate and median PRS length of the patients undergoing surgery and those with EGFR mutation were 60% (55 month) and 46% (35 month), respectively.

      Conclusion
      The PRS was still poor, but longer survival can be expected in selected patients, who have resectable recurrence or EGFR mutation.

    • +

      P3.07-045 - Thin-section computed tomography findings of lung adenocarinoma inherent with metastatic potential (ID 3259)

      09:30 - 09:30  |  Author(s): K. Nagai

      • Abstract

      Background
      Pulmonary solid nodules on chest computed tomography (CT) included inflammatory nodule, benign tumor, carcinoid tumor, small cell lung cancer, large cell carcinoma, large cell neuroendocrine carcinoma, squamous cell carcinoma, and poorly-differentiated adenocarcinoma, and so on. If the solid nodule was highly suspicious of malignant tumor or diagnosed as being primary lung cancer, a surgical resection would be recommended as expeditiously as practicable because of its metastatic potential. On the other hand, most well-defined ground-glass nodules including part-solid nodules were atypical adenomatous hyperplasias or lung adenocarcinomas. The development of spatial resolution on CT had provided improvement in predicting malignancy of these nodule shadow suspected of lung cancer. The aim of this study was to elucidate the preoperative chest thin-section CT (TSCT) findings of lung nodules which were inherent with metastatic potential from the perspective of recurrence and long term results.

      Methods
      We reviewed 392 primary lung adenocarcinomas with clinical T1N0M0 who underwent surgery between 2003 and 2007. Independent recurrence predicting parameters were extracted from the following ten parameters by using logistic regression analysis; sex, age, smoking index, preoperative serum carcinoembryonic antigen level, tumor location, maximum tumor size, consolidation tumor ratio (C/T ratio), tumor disappearance rate (TDR), the maximum size of consolidation at lung window setting (lung consolid), and the maximum size of consolidation at mediastinal window setting (med consolid). We evaluated extracted parameters by using receiver operating characteristic area under the curve (ROC-AUC) for recurrence prediction and identified these optimal cut-off levels of these parameters for prediction of whether patients had a good chance of being cured by surgical resection from their recurrence rate and survival.

      Results
      The median follow-up period was seven years. The 75 of 392 patients recurred. C/T ratio, lung consolid, and TDR were extracted as an independent recurrence predictor. ROC-AUC of these parameters was 0.70, 0.71, and 0.64 for predicting recurrence, respectively. If C/T ratio was 0.5 or less, distant metastatic recurrence was observed in only one of 75 patients and if lung consolid was 10 mm or less, it was also observed in only one of 82 patients. There were significant differences in overall survival and recurrence free survival among two populations divided by these cut-off levels of C/T ratio and lung consolid.

      Conclusion
      If the C/T ratio was 0.5 or less and/or lung consolid size was10 mm or less in cT1N0M0 lung adenocarcinoma patients, the recurrence rate was extremely low if they underwent a standard surgical resection. But when TSCT parameters of lung nodules exceeded these cut-off values, the recurrence rate wound increase and the prognosis would become worse even if they underwent complete resection. In these cases a prompt surgical resection would be recommended.