Changes of the lung cancer histology, diagnostic modality, stage, and smoking status among veterans over the past 20 years.

Abstract

e12054 Background: Recent SEER reviews indicated chenges in the histology pattern of Lung Cancer patients (pts) over the past 20 years and have been largely attributed to decrease of the incidence of smoking. We report the histology data, smoking status, diagnostic methods used and stage at our Institution for the last 20 years. Methods: We reviewed tumor registry data from 1990-1995 (group A) and compared to 2004-2009 data (group B). Comparison was made for histology, smoking status, diagnostic method use and stage. Results: On group A, 626 pts and on group B, 270 pts were recorded. In group A, 15 pts (2.3%) and B, 12 pts (4.4%) were non- or never smokers. The diagnosis was made by histology in 542 pts (86.6%) in group A and in 215 pts (79.6%) in group B, by cytology in 46 pts (7.3%) in group A and in 38 pts (14.1%) in group B. The stage was I-II in 94 pts (15%), stage III, in 157 pts (25%) and stage IV in 270 pts (43%) for group A and stage I-II in 22 pts (8.1%), stage III in 75 pts (27.7%) and stage IV in 137 pts (50.7%) for group B. By histology in group A,106 pts (16.9%) had large cell, 280 pts (44.7%) squamous cell,153 pts (24.5%) adenocarcinoma, 4 pts (0.6%) bronchioalveolar and 83 pts (13.3%) small cell. In group B, 93 pts (34.4%) had large cell, 71 pts (26.3%) squamous cell, 72 pts (26.7%) adenocarcinoma, 4 pts (1.5%) bronchioalveolar and 30 pts (11.1%) small cell histology. Conclusions: In our veteran population the majority of the pts are present or past smokers. The diagnosis by cytology has doubled likely due to the increasing use of CAT scan guided biopsies. Changes for the stage were seen but the importance is unclear due to the changes of the staging system used over the past 20 years. The major changes were observed in the decreasing incidence of the squamous and small cell in contrast to the increasing incidence of bronchioalveolar and adenocarcinoma histologies. Considering that major proportional decrease in the incidence of smoking was not recorded the etiology for the change of histology could be multifactorial. No significant financial relationships to disclose.