Lung Cancer in India–Part I

Abstract

Lung cancer in India has changed over the years. The subject was reviewed earlier in 2004. Since then, it has become an important and second common cancer in Indian males. Although smoking continued to be an important factor for the causation of lung cancer in this country, particularly bidi smoking, new facts come into light. Biomass fuel is another important factor in the causation of lung cancer in non-smoking females. There is also a regional disparity in the prevalence of lung cancer in India. Aizawl district had the highest rank in incidence rates in both males (38.8 per 100,000) and females (37.9 per 100,000). There was a significant increase in the incidence rates of lung cancer in Kamrup (urban), Chennai, Delhi and Bangalore PBCRs (Population Based Cancer Registries) in both males and females. Five PBCRs showed a significant increase in incidence rates among males whereas it was seen in 11 PBCRs among females. In Asia, among males, Yueyanglou (95.5 per 100,000) in China had the highest incidence rate of lung cancer, whereas Aizawl district (37.9 per 100,000), had the highest age adjusted ratio in females. Over the years, there is also marked improvement in the availability of diagnostic facilities all over the country. There is also a significant transition of the cell type of lung cancer. While earlier reports showed squamous cell type as the commonest one, now adenocarcinoma has surpassed that as reported from most centers in the country including the National Cancer Registry maintained by the Indian Council of Medical Research. Advent of molecular biology is a new development since we reviewed the topic nearly 16 years back. This aspect has been discussed in detail in the second part of the review. However, lung cancer continues to present in a very advanced stage of the disease where definite therapy, like surgery could not be offered to most of them. In fact around 3% to 4% of cases could only be offered surgery in our country. There is a significant improvement in the management of advanced stage lung cancer with the availability of newer chemotherapeutic drugs and targeted therapy and immunotherapy (will be discussed in 2nd part) with better median survival and many centers in the country are now treating this disease more aggressively. Although smoking continues to be a major problem in India, more and more anti-tobacco laws are being persued aggressively by the Government. Lung cancer screening is not yet practised in our country because of various technical, and other logistic issues. COVID-19 pandemic has created difficulties in managing such patients.