EC Pulmonology and Respiratory Medicine

Background: Lung cancer is a prominent global health challenge, constituting 11.4% of new cancer cases and 18% of cancer-related deaths. The prevalence of lung cancer in India is on the rise. No major studies have highlighted the changing trends in lung cancer in India. This study assessed the evolving trends in lung cancer for 6 years.

Aim: To study the trends in the epidemiology and histopathology of lung cancer over 6 years in North Kerala.

Study Design: Retrospective observational study using the electronic database of the hospital. All Patients with pathologically proven lung cancer attending a tertiary hospital in North Kerala between 2017 and 2022 were included. Data collected were analyzed using appropriate statistical tools.

Results: During the study period 418 lung cancer patients were included for evaluation. Among them 322 (77%) were males and 96 (23%) were females. The majority (315) were in the more than 60-year age group. 75 patients were active smokers, 240 were non-smokers, and 103 patients were ex-smokers. Adenocarcinoma (ADC) was the most frequent in 198 subjects followed by Squamous Cell Carcinoma (SCC) in 98, Small Cell Lung Cancer (SCLC) in 46, and the remaining 76 had rarer and unclassifiable tumours. At presentation regional disease was seen in 176, local metastasis in 68, and distant metastasis in 174 patients. Incidence of adenocarcinoma was found to be higher among non-smokers and the p-value was found to be significant for this association.

Conclusion: Adenocarcinoma emerged as the predominant histopathological type across all age groups, with the highest percentage in the 40 - 60 years age group. This age-related distribution provides crucial insights for targeted interventions and diagnostic strategies, particularly in the context of an aging population.

 Keywords: Lung Cancer; Trends; Smoking; Cancer Registry

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