The changing landscape of gastrointestinal cancers in India: An analysis involving published data from Cancer Incidence in Five Continents of 2013–2017 compared to 1988–1992

Population-based cancer registries (PBCRs) have reported changes in the patterns of gastrointestinal cancer (GIC) incidence in India over time. This study aimed at observing the differences in GIC incidence between 1988 and 1992 and 2013 and 2017 in selected Indian PBCRs.

GIC incidence data was extracted from two volumes of the Cancer Incidence in Five Continents (CI5). The ranking of GIC, crude rates and age-adjusted rates (AAR) were compared between the periods 1988 and 1992 and 2013 and 2017 for Mumbai, Bengaluru, Chennai and Barshi PBCRs. Differences in AAR were expressed through standardized rate ratios (RR) with 95% confidence intervals (95% CI).

Esophageal and gastric cancer used to rank among the most common cancers in 1988 to 1992. In the past three decades, their AAR declined significantly by 20% to 64%. The AAR observed in 1988–1992 for esophageal cancer reduced to one-third by 2013–2017 in both sexes (RR 0.36, 95% CI 0.33–0.4) in Mumbai. Gastro-esophageal cancers are being replaced, epidemiologically, by colorectal and hepatobiliary cancers. Highest increase in incidence was observed in the females of Chennai, where colorectal cancer has doubled (RR 1.99, 95% CI 1.75–2.28), while hepatic and gallbladder cancer have tripled in this period (RR 3.44, 95% CI 2.54–4.65 for liver; RR 3.57, 95% CI 2.62–4.87 for gallbladder). This can be attributed to changes in age structure, differences in risk factor prevalence, development of and access to health infrastructure and globalization.

This study reports an increase in the incidence of colorectal and hepatobiliary cancers, on the basis of data from three metropolises and one rural area in India. This study is limited by the unavailability of long-term PBCR data from other regions of the country. GICs are among the top five leading cancers with high mortality in India. To tackle this burden, programmes must focus on primary prevention, health awareness and improved access to early diagnosis and treatment.