Changing trends in histopathology of lung cancer in a tobacco prevalent area of South India

Abstract

Background: Lung cancer is the most devastating disease of mankind among all cancers in the world with 1.8 million cases. In the west, adenocarcinoma of lung is the most common type, accounts for 38.5% followed by squamous 23% and large cell carcinoma. In India, squamous cell carcinoma was common until few recent studies which described the changing trends. Present study is done at a tertiary care hospital where tobacco cultivation and consumption is rampant in its surrounding places. An attempt to assess the histological trends in this area is made. Methodology: Total of 450 lung cancer patients, were studied in a span of 7 years. Results: Out of 450360 cases were histopathologically proven, 255 (70.83%) were males and 95 (26.38) were females with a male to female ratio of 2.7:1. Adeno carcinoma was found in 215 (59.72%) being most common, followed by squamous cell carcinoma 81(22.50%), small cell 23 (6.38%), large cell 12 (3.3%), and others 31(7.5%). Adenocarcinoma is the most common histopathological type seen in both males and females with 147 (57.64) cases, and 63 (66.31%) cases respectively. Adenocarcinoma is the most common histopathological type seen in both smokers and non-smokers with 246 (68.33%) and 114 (31.66%) respectively. Conclusions: Adenocarcinoma is evolving to be the most common histological type in both smokers and non-smokers in India. Tobacco cessation and change to filtered cigarettes has globally reduced tobacco related histological types of lung cancers. The aetiology of adenocarcinoma should be further evaluated in order to achieve an overall prevention. Keywords: Adenocarcinoma; Lung cancer; Squamous cell carcinoma.