65P - Lymph node metastases in clinically node negative peripheral non-small cell lung cancer

Date 07 May 2017
Event ELCC 2017
Session Poster Display Session
Topics Non-Small-Cell Lung Cancer, Early Stage
Lung and other Thoracic Tumours
Presenter Tahir Mehmood
Citation Annals of Oncology (2017) 28 (suppl_2): ii20-ii23. 10.1093/annonc/mdx085
Authors T. Mehmood
  • Shaukat Khanum Memorial Cancer Hospital and Reserch Centre (SKM), 13014 - Lahore/PK

Abstract

Background

Small lung cancers are increasingly detected with the advent of low dose spiral computed tomography and lung cancer screening programme, and these lesions are frequently subsolid and low risky pN+ disease. Integrated positron emission tomography/computed tomography (PET/CT) is widely used in lymph node staging with higher accuracy and sublobar resection may be appropriate in cN0 NSCLC. This retrospective study was designed to identify the risk factors and pattern of lymph node metastases in NSCLC.

Methods

107 consecutive cN0 patients with 1 cm to 2 cm peripheral NSCLC who underwent PET-CT scans followed by curative-intent resections in our hospital were enrolled in this study. Clinical and pathological data were analyzed by multivariate analysis retrospectively, including tumor size, tumor SUVmax, ratio SUVmax tumor/SUVmax liver. Lymph nodes of metastases were analyzed in pN+ patients.

Results

8.5% (9/107) PET-CT diagnosed N0 NSCLC cases had pathological lymph node metastases, including 8 N1 and 3 N2 involvement (1 skipping N2 metastases). Univariable and multivariable analysis of clinicopathological factors (including tumor size, ratio SUVmax tumor/liver) found no independent risk factor for lymph node metastases. All N(+) cases were adenocarcinoma while 66.7% (6/9) of the N(+) cases were single station metastases. The lymph node metastasis rate of solid NSCLC and GGO were 10.7% and 0% (P=0.224), respectively.

Conclusions

The lymph node rate of 1 cm to 2 cm NSCLC is relatively high and intrapulmonary lymph nodes were higher risk than mediastinal lymph nodes. However, no predictors of lymph node metastases were detected in this population. Sublobar resection can be an alternative procedure for GGO lesions as no lymph node metastases were found, but for solid NSCLC, thorough lymph node sampling should be performed to rule out lymph node metastases before making the decision of segmentectomy.

Clinical trial identification

Legal entity responsible for the study

SKMH, Lahore

Funding

SKMH, Lahore

Disclosure

The author has declared no conflicts of interest.