Patterns of histological types of lung cancer have changed over time. In the United States, adenocarcinoma has become the most commonly diagnosed type of lung cancer. By contrast, in Europe squamous cell carcinoma remains the most predominant cell type. Since changes in histological type of lung cancers may be indicative of changes in causal factors, it is important to identify whether any changes in histological subtypes are real or artefactual. Present study is done to analyse the change in trends in incidence and histopathology patterns of lung carcinoma in a tertiary care hospital in Kerala over a span of 10 years.

Aims and Objectives: Changes occurred in the frequency of lung carcinoma in Kerala over a period of 10 years from 2004 was observed. Histological pattern distribution according to demographic variables were analysed.

Material and Methods: Retrospective cohort study conducted in a tertiary care hospital during the period of 10 years from 2002. Comparison of cases of lung tumors diagnosed in the Department of Pathology, Government Medical College Kottayam in India during the period of 3 years from January 2002 to December 2004 to January 2012 to December 2014 was done. Age and gender distribution changes in occurrence and histopathology patterns was studied using the registers and histopathology slides available in the department.

Statistical Analysis: Data was analysed using SPSS. Descriptive statistics used to evaluate the changes in the histological pattern

Results: Of the 50 malignant tumours studied in 2002, 50% were Squamous cell carcinoma, whereas it was 35.8 % in the 80 cases studied in 2012. 30% of the tumors were Adenocarcinoma in 2002-2004 and 30.9 % in 2012-2014. 90% cases were males and 10% females in both the study period. Highest percentage of squamous cell carcinoma (64%) was seen in the 51-70 year age group and 46.7% of adeno carcinoma was found  in the age group of 61-70 in the year 2002-2004. Age distribution of squamous cell carcinoma was found highest in the 51-60 years (42.9%) and adenocarcinoma prevalence was found high (52%) in the 61-70 year age group in 2014.

Keywords: Changes, histopathology, lung cancer.

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Subitha Kandamuthan

Associate Professor of Pathology, Government Medical College Thrissur, Kerala