Author of

• 11794

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  P2.12 - Poster Session 2 - NSCLC Early Stage (ID 205)

  • Event: WCLC 2013
  • Type: Poster Session
  • Track: Medical Oncology
  • Presentations: 1
  • Moderators:
  • Coordinates: 10/29/2013, 09:30 - 16:30, Exhibit Hall, Ground Level

  • 11806

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    P2.12-012 - Prognostic impact of visceral pleural invasion in resected tumors of non-small cell lung cancer (ID 1622)

    09:30 - 09:30  |  Author(s): M. Miyawaki
    • Abstract

    Background
    A standardized definition of visceral pleural invasion (VPI) has been incorporated into the 7th edition of TNM, and the recommendations include the use of elastic stains to determine the VPI. PL0, defined as a lack of pleural invasion beyond the elastic layer, is not regarded as a T factor. In tumors of 3 cm or less, PL1 was defined as invasion beyond the elastic layer, and PL2 was defined as invasion to the surface of the visceral pleura, both of which are classified as indicators of T2 disease. The purpose of this retrospective study was to evaluate the validity of this definition.

    Methods
    We retrospectively reviewed 493 NSCLC patients with pathological N0M0 with a size of 5 cm or less with PL0-2 who underwent curative resection by lobectomy or segmentectomy between 1999 and 2013. We evaluated the disease-free survival (DFS) and overall survival (OS) in relation to the grade of VPI.

    Results
    The median follow-up for overall survival was 39 months after the operation. There were 282 males and 211 females included in the study. The age of the patients ranged from 31 to 90 years, with a mean of 69 years old. There were 347 patients in stage IA and 146 in Stage IB, and the histological type was adenocarcinoma in 374 patients (75.8%), squamous cell carcinoma in 91 patients (18.4%) and others in 28 patients (5.8%). The 5-year survival rates by PL grade were as follows: 85.0% for PL0 (n=425), 73.3% for PL1 (n=50) and 70.8% for PL2, respectively. In patients with tumors 3 cm or less in diameter, the 5-year survival rates and 5-year DFS rates were as follows: 87.9% and 88.2% for PL0 (n=342), 71.6% and 86.9% (n=30) for PL1 and 90.7% and 80.0% (n=11) for PL2, respectively. The 5-year survival rate of cases with PL0-T2a (> 3 cm, ≤ 5 cm) was 71.2%, and that for PL1-T2a was 71.6%, which did not differ significantly. Postoperative recurrence was observed in 47 patients (9.5%). Distant metastases were observed in 3.1% of PL0 patients, 10.0% of PL1 patients and 11.1% of PL2 patients, which showed significant difference between PL0 and PL1/2. However, no difference was found in the local recurrence rates between PL0 and PL1/2 patients.

    Conclusion
    The grade of VPI defined by the TNM 7th edition is reasonable. Namely, PL1 indicates visceral pleural invasion, and can be regarded as T2a disease.