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O. Ozyilkan



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    P1.09 - Poster Session 1 - Combined Modality (ID 212)

    • Event: WCLC 2013
    • Type: Poster Session
    • Track: Combined Modality
    • Presentations: 2
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      P1.09-007 - Prognostic Value of Number of Chemotherapy Cycle in Stage IIIB Non-small Cell Lung Cancer Patients Treated with Thoracic Radiotherapy and Concurrent Cisplatin-Vinorelbine (ID 937)

      09:30 - 09:30  |  Author(s): O. Ozyilkan

      • Abstract

      Background
      The study was aimed to evaluate association between number of chemotherapy (CT) cycles and prognosis in stage IIIB non-small cell lung cancer (NSCLC) patients treated with thoracic radiotherapy (TRT) and concurrent CV CT protocol given in 1-3 cycles according to the toxicity or patient preference.

      Methods
      A total of 475 18-70 years old stage IIIB NSCLC patients, who received 60-66 Gy TRT concurrently with at least 1 cycle CV (q21) regimen between January 2007 and December 2011 were retrospectively evaluated. Primary end point was overall survival (OS), and secondary end points were progression-free survival (PFS) and locoreginal PFS (LRPFS).

      Results
      Median follow-up time was 21.7 months (range 17-24.1). Histolopathologic subtype was squamous cell in 51.8%, and adenocarcinoma in 48.2% of cases. Treatment-related mortality was reported in 6 (1.3%) patients. There was no grade-4 non-hematological toxicity but grade-4 hematological toxicity was observed in 59 (12.4%) patients. Respective grade-3 non-hematological and hematological toxicity rates were 14.5% (n=69) and 24.6% (n=117), with leukopenia (9.3%) and esophagitis (17.3%) being the most common toxicities. Median OS, PFS and LRPFS for whole group were 20.7 (%95 CI: 19.4-22.0), 9.9 (%95 CI: 9.9-10.4) and 13.4 months (%95 CI: 12.6-14.2), respectively. Comparative median OS, PFS and LRPFS results for groups receiving 1 (n=44), 2 (n=68) and 3 (n=363) cycles of chemotherapy were 13.2 vs. 19.3 vs. 21.9 months ( p≤0.001), 6.1 vs. 9.7 vs. 10.5 months (p≤0.001), 6.6 vs. 12.8 vs.14.2 months ( p≤0.001), respectively. For all survival parameters, there were significant difference between patients receiving 1 cycle and 2 or 3 cycles of chemotherapy (p<0.05 for each) but there was no difference between those receiving 2 and 3 cycles of chemotherapy (p≥0.05 for each). T-satge (T1-2 vs T3-4) and N-stage (N2 vs N3) were the other factors influencing OS (p<0.05 for each) on univariate analyses. However, only T-stage (p=0.004) and Number of chemotherapy cycles (p≤0.001) retained prognostic significance on multivariate analyses.

      Conclusion
      Our results revealed that CV protocol was a relatively well-tolerated chemotherapy regimen given concurrently with TRT in stage IIIB NSCLC cases, and number of chemotherapy cycles than could be given during TRT course was an important prognostic indicator in such patients. Although results of randomized trials are needed, findings of superior survival in cases receiving 2 or 3 cycles of chemotherapy during TRT and similar survival results between 2 and 3 cycles suggest that 2 cycles of chemotherapy may potentially reduce toxicity rates, which results in increased treatment tolerability and quality of life, without compromising efficacy of treatment.

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      P1.09-015 - Impact of Pretretment Leukocytosis on Prognosis in Locally Advanced Non-Small Cell Lung Cancer Patients Treated with Concurrent Chemoradiotherapy (ID 1843)

      09:30 - 09:30  |  Author(s): O. Ozyilkan

      • Abstract

      Background
      Purpose of this study was to evaluate the association between pretreatment thrombocyte count (TC) and prognosis in locally advanced non-small cell lung cancer (LA-NSCLC) patients treated with concurrent chemoradiotherapy (CRT).

      Methods
      Medical records of 792 LA-NSCLC patients, who had been treated with definitive CRT at our department between dates January 2007 and December 2011, and whose pretreatment TC values are available, were retrospectively evaluated. All patients received 60-66 Gy thoracic 3-dimentional conformal radiotherapy concurrently with 1-3 cycle cisplatin/carboplatin-vinorelbine/taxane (q21) doublet chemotherapy. For all analyses, patients were divided into two groups according to their pretreatment TC: Group-1: normal (130.000-400.000; n=639) and Group-2: high (>400.000; n=153). Primary and secondary end points were overall survival (OS), and progression-free survival (PFS), respectively.

      Results
      At a median follow-up of 23.1 months (range 18.8-24.6), Median PFS and OS for whole group were 10.1 (%95 CI: 9.7-10.5) and 20.9 months (%95 CI: 20.9-22.9), respectively. On comparative survival analyses, patients with high pretreatment TC had inferior OS (23.2 vs. 15.6 months; p≤0.001) and PFS (10.6 vs. 7.8 months; p<0.001) than those with normal TC. Similarly, 3-years OS was significantly lower in Group-2 patients (8.9 vs. 33%, p<0.001). TC cut-off value determined from ROC curve analysis was 278.000, and median OS (18.7 vs. 24.5 months; p<0.001 and PFS (9.1 vs. 11.3 months, p<0.001) was significantly lower in patients with TC above this cut-off point. On univariate analyses, T-stage (T1-2 vs. 3-4), N-stage (N2 vs. N3), pretreatment TC (130.000-400.000 vs. >400.000), and ROC TC cut-off (<278.000 vs. ≥278.000) were the significant prognostic factors (p<0.05 for each), which retained their significance on multivariate analyses as well (p<0.001, 0.022, <0.00, 0.01, respectively).

      Conclusion
      Results of this study has shown that pretreatment TC may be a relevant and independent prognostic factor that can potentially be used besides other well-known factors to predict treatment outcomes in LA-NSCLC patients treated with definitive CRT.

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    P1.15 - Poster Session 1 - Thymoma (ID 189)

    • Event: WCLC 2013
    • Type: Poster Session
    • Track: Thymoma & Other Thoracic Malignancies
    • Presentations: 1
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      P1.15-005 - Multimodality treatment for thymoma and thymic carcinoma: Results of a single center experience. (ID 1665)

      09:30 - 09:30  |  Author(s): O. Ozyilkan

      • Abstract

      Background
      There are no randomized clinical trials that provide clear algorithm for the management of patients with thymoma or thymic carcinoma due to the rarity of these tumors.We review our experience with a multimodal approach in fourteen cases

      Methods
      Patients with thymoma and thymic carcinoma who were treated with multimodality treatment in our center between periods of 2006 and 2012 were retrospectively analyzed. Basic demographics, clinicalcharacteristics’ of the patients such as status of stage of tumor according to Masaoka Staging System, type of systemic chemotherapy, presence of paraneoplastic myasthenia gravis syndrome and surgical marginswere collected.

      Results
      Fourteen eligible patients were analyzed retrospectively. There were seven (50%) thymic carcinoma and seven (50%) thymoma. Included were 14 patients with a mean age of 50 years. Three patients (21.4%) had diagnosis of Myasthenia Gravis initially. There were four patients (28.6%), nine patients (64.3), one patient (7.1%) at stage II, Stage III, and stage IV, respectively. Nine patients were treated with multimodality treatment including surgery, chemoradiotherapy and adjuvant chemotherapy. Five patients were treated with chemoradiotherapy and adjuvant chemotherapy without surgical excision. Eight patients out of nine patients who were treated with primary surgery had positive resection margin (R1).Adjuvant protocol was consisted of cisplatin based chemotherapy. Median overall survival was 55 months (95% CI 11,4-98,5).One, two, and three year survival rate for thymoma was 85%, 85%, and 85%. Although, statistical analysis failed to show significant difference one, two, and three year survival rate for thymic carcinoma was inferior and found as 85%, 70%, and 43%, respectively. We were not able to show significant effects of patient and tumor baseline characteristics on overall survival.

      Conclusion
      Overall survival in our analysis seems to relatively inferior when compared with literature. We suggest that this result may be related with high rate of positive surgical margins and even absence of surgical excision in five patients a part of multimodal treatment.

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    P1.22 - Poster Session 1 - Epidemiology, Etiology (ID 166)

    • Event: WCLC 2013
    • Type: Poster Session
    • Track: Prevention & Epidemiology
    • Presentations: 1
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      P1.22-004 - Pathologic subgroup analysis in patients who were diagnosed as non-small cell lung carcinoma and analysis of its effect together with basic demographic and clinical characteristics of patients on survival parameters. (ID 1673)

      09:30 - 09:30  |  Author(s): O. Ozyilkan

      • Abstract

      Background
      Lung cancer is the most common cause of cancer-related deaths in the world. In the last decades, the patients with adenocarcinoma histology have been increasing, although we don’t know the exact reason, and now constitute most common histological subgroup of Non-small Lung Carcinoma (NSCLC).Main aim of this study is analysis of histological subgroup of NSCLC, changing of histological subgroupsover time and its effect on survival parameters.

      Methods
      We analyzed 493 NSCLC patients those who were followed at our department between January 2006 and December 2011. Basic demographic and clinical characteristics such as stage of disease, initial diagnostic tests including invasive procedures, immunohistemochemical methods to clarify the histopathological subgroups, treatment protocols together with survival parameters were recorded retrospectively.

      Results
      Included were 493 patients with a median age of 60 years (35-102). There were 426 men (86.4%)and 67 women(13.6%)446 (90.5%) patients had a history of cigarette smoking. The percentage of female patients in whole group had been increased over timenonsignificantly(p=0.24). We found that adenocarcinoma was most common histopathological diagnosis (44.9%). Better performance status, early diagnosis, and adenocarcinoma histology exhibit statistically significant effect on overall survival with p values of (p=0.003,p=0.054, p=0.006), respectively. Statistical analysis showed that overall survival and TTF-1 positivity were significantly increased over time in the study with p values of (p=0.011) and (p=0,001) respectively. We also found that TTF-1 positivity was higher in female gender (p=0.005). Additionally,we were not able to show significant effects of basic demographic and clinical characteristicsof the patients such as age, TTF-1 positivity and primary localization of tumor on overall survival (p>0.05).

      Conclusion
      Our study showed that adenocarcinoma is the dominant histology of NSCLC in Turkey and the percentage of female patients in NSCLC and overall survival in NSCLC had been increased significantly over time.Patient and tumor characteristics, such as histological shifting to adenocarcinoma over time, that we found during our study is compatible with literature.

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    P2.08 - Poster Session 2 - Radiotherapy (ID 198)

    • Event: WCLC 2013
    • Type: Poster Session
    • Track: Radiation Oncology + Radiotherapy
    • Presentations: 2
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      P2.08-006 - Efficacy of Single Dose 8-Gy Palliative Chest Irradiation in Pain Palliation of Patients with Locoregionally Recurrent Stage IV Non-Small Cell Lung Cancer (ID 938)

      09:30 - 09:30  |  Author(s): O. Ozyilkan

      • Abstract

      Background
      To investigate the efficacy of single dose 8-Gy palliative chest re-irradiation (PCRI) in metastatic non-small cell lung cancer (M-NSCLC) patients with painful recurrences in previously irradiated thoracic region.

      Methods
      Clinical data of 63 M-NSCLC patients, who received single dose 8-Gy PCRT due to painful thoracic recurrences from February 2007 to June 2010 were retrospectively analyzed. All patients had previously received upfront definitive 60-66 Gy concurrent chemoradiotherapy (C-CRT), and 52 of them had also received salvage chemotherapy. Primary endpoint was change in visual analogue score (VAS), and secondary endpoints were time to lowest VAS record and duration of pain control.

      Results
      Treatment was well tolerated with only 3 (4.8%) grade III radiation-induced pneumonitis. For all patients median, 1-, 2-year survival were 9.2 months, 28.4%, and 12.3%. Median pre-PCRI and minimum achievable post-PCRI VAS values were 6.7 (range: 5-8) and 3.4 (range: 0-8), and the decline in VAS values was statistically significant (p<0.001). Objective response defined as reduction of at least 2 points in VAS value was achieved in 54 (85.7%) patients. Median time to lowest VAS and duration of pain control were; 27 (95% CI: 21 - 33) days and 7.1 (95% CI: 6.3 - 7.9) months, respectively.

      Conclusion
      Single dose 8-Gy PCRI is safe and highly efficient in palliating moderate to severe pain in locoregionally recurrent M-NSCLC patients, who have previously received upfront definitive C-CRT

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      P2.08-007 - Impact Surgical Resection and Radiosurgery Directed To Brain Metastasis on Survival Outcomes in Non-Small Cell Lung Cancer Patients with Synchronous Single Brain Metastasis (ID 1848)

      09:30 - 09:30  |  Author(s): O. Ozyilkan

      • Abstract

      Background
      Aim of this study was to compare surgical resection and radiosurgical treatment modalities directed to brain metastasis (BM) in terms of survival outcomes in newly diagnosed non-small cell lung cancer (NSCLC) patients with synchronous single brain metastasis (SSBM).

      Methods
      Medical records of medically fit NSCLC patients with SSBM treated at our department were retrospectively evaluated. A total of 64 patients were staged with PET-CT besides conventional staging tools. TRT to a total dose of 66 Gy in 2 Gy fx was delivered with 2 cycles of concomitant cisplatin –based chemotherapy (CT) following surgery+30 Gy whole-brain RT (WBRT) (n:33) or 30 Gy WBRT+stereotactic radiosurgery (SRS) (n:31) for their BM.

      Results
      Pretreatment patient characteristics were given in Table. Whole study population could complete planned treatment to their BM and thoracic primaries. At median 20.7 months (7.1-58.7) of follow-up, Median overall (OS), neurological progression-free (NPFS), locoregional progression-free (LRPFS) and progression-free survival (PFS) were 23.4, 22.8, 14.9, ve 9.4 months, respectively. There was no statistically significant survival difference between two groups (p>0.05 for each survival parameter) (Figure 1). On univariate analyses, patients with ECOG performance status of 0-1 (p<0.001), younger than median 50 years (p=0.031) and with no weight loss (p=0.001) revealed superior OS. On multivariate analyses performed with these factor, all factors except age retained their independent prognostic value (p<0.05 for each parameter). Table 1. Pretreatment patient characteristics Figure 1Figure 2

      Conclusion
      Results of this study has shown that, in line with the literature, surgical or radiosurgical treatment modalities directed to SSBM in NSCLC patients could not demonstrate any superiority over each other. Therefore, management of BM should be tailored according to the facilities available, and patient or disease-specific conditions. Moreover, although larger prospective data are needed, survival outcome in such patients similar to locally advanced patients indicates the potentially curative role of definitive CRT.

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    P2.09 - Poster Session 2 - Combined Modality (ID 213)

    • Event: WCLC 2013
    • Type: Poster Session
    • Track: Combined Modality
    • Presentations: 1
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      P2.09-009 - Impact of Change in Hemoglobin Levels During Treatment on Prognosis in Non-anemic Locally Advanced Non-Small Cell Lung Cancer Patients Treated with Concurrent Chemoradiotherapy (ID 1836)

      09:30 - 09:30  |  Author(s): O. Ozyilkan

      • Abstract

      Background
      Purpose of this study was to evaluate the association between change in hemoglobin (Hb) levels during treatment and disease control and survival in locally advanced non-small cell lung cancer (LA-NSCLC) patients treated with concurrent chemoradiotherapy (CRT).

      Methods
      Medical records of 368 LA-NSCLC patients, who had been treated with definitive CRT at our department between dates January 2007 and December 2011, and whose pretreatment Hb levels were ≥12.0 g/L, and who had at least 3 Hb measurements during CRT, were retrospectively evaluated. All patients received 60-66 Gy thoracic 3-dimentional conformal radiotherapy concurrently with 1-3 cycle cisplatin/carboplatin-vinorelbine/taxane (q21) doublet chemotherapy. For all analyses, patients were divided into groups according to their nadir Hb level, percent Hb change, development of anemia (Hgb<12) and nadir Hb cut-off defined from ROC analysis. Primary end point was overall survival (OS), and secondary end points were progression-free survival (PFS) and locoreginal PFS (LRPFS).

      Results
      At a median follow-up of 24.7 months (range 19.7-27.5), Median OS, PFS and LRPFS for whole group were 23.8 (%95 CI=22.8-24.8), 11.7 (%95 CI=11.0-12.5) and 15.3 months (%95 CI=14.7-15.9), respectively. During CRT course, 138(37.5%) patients developed anemia, and median OS, PFS, and LRPFS were significantly worse in these patients [(27.3 vs. 18.3; p<0.001), (12.7 vs. 9.2; p<0.001), and (16.4 vs. 11.2 months; p<0.001)]. While there was no statistically significant survival difference according to median nadir Hb level and % Hb change, patients with Hb levels above the cut-off point defined from ROC curves (12.4 g/L) revealed better OS (27.7 vs. 20.4; p<0.001), PFS (12.8 vs. 10.2; p<0.001) and LRPFS (16.4 vs. 13.8 months; p<0.001). On multivariate analyses, only these two factors found to be independent prognostic factors (p<0.001 for Hb > vs. < 120 g/L, p<0.03 for Hb> vs.

      Conclusion
      Results of this study has shown that 37.5% NSCLC patients with normal pretreatment Hb levels had developed anemia during the course of CRT, which was found to be a worse prognostic factor independent from other co-existing factors in terms of locoregional tumor control and survival outcome.

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    P2.10 - Poster Session 2 - Chemotherapy (ID 207)

    • Event: WCLC 2013
    • Type: Poster Session
    • Track: Medical Oncology
    • Presentations: 1
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      P2.10-044 - Impact of comorbidities on survival in elderly patients with non small cell lung cancer. (ID 2808)

      09:30 - 09:30  |  Author(s): O. Ozyilkan

      • Abstract

      Background
      Lung cancer comprises 14% of all cancers and 29% of cancer related deaths. Mean age at diagnosis is 60, therefore it’s a disease of elderly. Comorbidities are common in this group of age. Comorbidities can affect survival, quality of life, and patients’ tolerability for therapy, as well. Nevertheless, data on the effects of comorbidities over lung cancer are limited. What we aimed with this study is to use Charlson comorbidity index (CCI) in order to define and stratify the comorbidities of our elderly patients (i.e ≥65 years) with non small cell lung cancer (NSCLC) and analyze its effect over disease-free survival (DFS) and overall survival (OS).

      Methods
      154 patients with NSCLC aged 65 and over were included in this study. Data were retrospectively collected from patients’ files. Patients’ comorbidities were classified using CCI and its effect on DFS and OS along with other prognostic factors were evaluated.

      Results
      Mean age of patients for diagnosis in this study was 70 years. Thirty patients (19,4%) had stage I disease, 17 (11%) had stage II, 46 (29,9%) had stage III, and 61 (39,6%) had stage IV disease. Fifty patients had at least one comorbid disease (min; 0 max; 6). CCI scores of the patients were as follows ; 22 patients (14,2 %) had 0 point, 59 patients (38,3 %) had 1 point, 39 patients (25,3 %) had 2 points, 22 patients (14,3%) had 3 points, 8 patients (5,2%) had 4 points, 3 patients (1,9%) had 5 points and 1 patient (0,6%) had 6 points. When patients were classified into 2 groups according to CCI scores (Group 1; CCI 0 and 1, group 2; CCI≥2), DFS of group 1 and group 2 were 13,2 and 16,9 months respectively, and OS were 21,9, and 23,1 months respectively. There was no statistically significant difference between 2 groups (p>0,1 for all comparisons). Survival rates were also similar when compared according to age-adjusted CCI scores of the two groups. The only significant predictors of both dfs and os were disease stage, Eastern Cooperative Oncology Group (ECOG) performance status and the presence of weight loss in multivariate Cox regression analysis.

      Conclusion
      In conclusion, comorbid diseases stratified according to the CCI were found not to be associated with DFS or OS in elderly patients with NSCLC in our study. The only predictive factors of survival were performance status, weight loss and disease stage. Negative results may be due to low validity of the CCI score in NSCLC, underreporting of comorbidities in patient files or aggressive biology of NSCLC which overrides comorbidities being the most imortant predictor of survival. Prospective studies with larger number of patients are needed to clarify these points.

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    P3.09 - Poster Session 3 - Combined Modality (ID 214)

    • Event: WCLC 2013
    • Type: Poster Session
    • Track: Combined Modality
    • Presentations: 2
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      P3.09-008 - Prognosis of Stage III Non-Small Cell Lung Cancer Patients Initially Presenting with Superior Vena Cava Syndrome Treated with Partially Accelerated Definitive Concurrent Chemoradiotherapy (ID 1814)

      09:30 - 09:30  |  Author(s): O. Ozyilkan

      • Abstract

      Background
      To retrospectively investigate the prognosis of locally advanced non-small cell lung cancer (LA-NSCLC) patients initially presenting with superior vena cava syndrome (SVCS) following partially accelerated definitive concurrent chemoradiotherapy (C-CRT).

      Methods
      Forty-seven LA-NSCLC patients presented with SVCS between June 2007 and December 2011 were included. All patients received an initial daily 4 Gy radiotherapy (RT) followed by weekly cisplatin-based chemotherapy given concurrently with 2 Gy daily RT for additional 26 fractions, which corresponds to a biologically equivalent dose (BED10) of 79.2 Gy. Primary endpoint was overall survival (OS).

      Results
      Median follow-up time was 20.3 months for whole cohort, and 37.4 months for surviving patients. Median age was 63 years. Squamous cell- and adenocarcinoma rates were 54 and 46%, respectively. Stage distribution was 29.8% stage IIIA and 70.2% stage IIIB. Treatment was relatively well tolerated. All patients were able to receive planned RT, and 39 (83%) received 4 or 5 courses of prescribed chemotherapy. There were no treatment related deaths at acute phase while 8 (17%) grade 4 hematologic toxicity was reported, with no grade 4 non-hematologic toxicity. At long term 2 patients died of tracheoesophageal fistula and caval rupture. Median, 2-, and 3-year OS were 19.4 months, 36.2%, and 25.5%, respectively. On univariate analyses; cause of SCVS (nodal vs. primary tumor; p<0.001), status of SVC (infiltrated vs. compressed; p<0.001), and tumor stage (IIIA vs. B; p<0.03) were the factors significantly associated with prognosis. Of these, cause of SCVS (p<0.001) and status of SVC (p<0.001) retained their significance on multivariate analyses.

      Conclusion
      Partially accelerated C-CRT regimen utilized here is reasonably safe and efficient in LA-NSCLC patients initially presenting with SVCS. Present survival rates, which are almost equivalent to those reported for similarly staged patients without SVCS suggest treatment of such patients with aggressive C-CRT protocols.

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      P3.09-010 - Long Treatment Duration is Associated with Poor Prognosis in Patients Receiving Concurrent Chemoradiotherapy with The Diagnosis of Stage IIIB Non-Small Cell Lung Cancer (ID 1844)

      09:30 - 09:30  |  Author(s): O. Ozyilkan

      • Abstract

      Background
      Aim of this study is to investigate the relationship between the treatment duration on prognosis in stage IIIB non-small cell lung cancer (NSCLC) patients treated with definitive concurrent chemoradiotherapy (CRT).

      Methods
      Medical records of 824 18-70 years old stage IIIB NSCLC patients treated at our department between dates January 2007 and December 2011 were retrospectively evaluated. Patients received 60-66 Gy thoracic radiotherapy concurrently with at least 1 cycle cisplatin-vinorelbine/docetaxel (q21) regimen chemotherapy. Primary end point was the evaluation of association between treatment duration and overall survival (OS), and secondary end points were progression-free survival (PFS) and locoreginal PFS (LRPFS).

      Results
      At a median follow-up of 22.8 months (range 17.4-25.2), Median OS, PFS and LRPFS for whole group were 21.2 (%95 CI: 20.2-22.2), 9.9 (%95 CI: 9.4-10.3) and 13.7 months (%95 CI: 13.1-14.3), respectively. The most significant cut off point for CRT duration defined in ROC (receiver operating characteristic) curve analysis was 50.5 days, and patients were dichotomized into two groups; namely Group 1: ≤50 (n=420) and Group 2: ≥ 50 (n=404). On comparative survival analyses, patients completing their CRT in shorter period of time revealed superior OS (26.6 vs.15.5 months; p<0.001), PFS (12.8 vs.7.7 months; p<0.001), and LRPFS (16.4 vs.10.2 months; p<0.001) than the others. Duration of CRT retained its significant association with OS, PFS, and LRPFS on multivariate analyses (p<0.001).

      Conclusion
      Results of this study has demonstrated that completion of CRT in longer than 50 days was associated with significantly shorter survival. Therefore, treatment delays due to religious or official holidays should be avoided, and all comprehensive palliative measures should be performed in order to minimize treatment-related toxicities that might potentially prevent shorter delivery of CRT.