MA12.09 Comparative Histological Subtype Analysis of Lung Adenocarcinoma Tumor and Metastatic Lymph Nodes and the Prognostic Impact

Abstract

The goal of this study is to investigate comprehensive comparative pathological analyses of both primary tumor and metastatic lymph node (LN) and correlate with lung cancer-specific death (LC-death) in patients with LN-positive lung adenocarcinoma. PN1/2 lung adenocarcinoma patients who underwent R0 resection without induction therapy (n=402, 2000-2012) were included in the study. In primary tumor, lymphatic/vascular/pleural invasion, necrosis, tumor spread through air spaces (STAS), as well as histologic subtypes according to 2015 WHO classification were evaluated. In metastatic LN, metastatic tumor size, extracapsular invasion, histologic subtypes were evaluated. Recurrence and LC-death were analyzed by Cox model. Micropapillary and solid predominant subtypes were more frequent in LN metastases than in primary tumors (Figure). In multivariable analyses, adjuvant chemotherapy, pleural invasion, extracapsular invasion of LN metastasis, micropapillary predominant subtype in LN metastasis were independent factors for recurrence; adjuvant chemotherapy, pleural invasion, tumor STAS, and extracapsular invasion were for LC-death (Table). In lung adenocarcinoma lymph node metastases, predominant micropapillary pattern and extracapsular invasion indicate high risk for recurrence and lung cancer-specific death.View Large Image Figure ViewerDownload Hi-res image Download (PPT)