Trends in incidence of head and neck cancers in India.

Information relating to cancer incidence trends forms the scientific basis for the planning and organization of prevention, diagnosis and treatment of cancer in a community. An attempt was here made to study the trends in the age adjusted incidence rates for the sites of head and neck cancers in Mumbai, Bangalore, Chennai, Delhi, Bhopal, and Barshi registry's populations. For carrying out trend analysis the gum, the floor of mouth, the mucosa of cheek, the hard and soft palate and the uvula were grouped together and assigned as cancers of mouth. The trend analysis was carried out for all sites together, tongue, mouth, hypopharynx and larynx in males and all sites together and mouth in females. Sites such as lip, hypopharynx and nasopharynx were not considered. In males, for all sites together linear regression showed no increase or decrease in age adjusted rates overall for Bangalore and Delhi registries, a significant decrease for Mumbai and Delhi registries, but a rising trend for Chennai and Bhopal registries over a period of time. In females, for all sites together no change was observed in age adjusted incidence rates for Mumbai, Chennai, Bhopal, Bangalore and Barshi registries while a decreasing trend was noted for Delhi registries over a period of time. For the specific sites, variation among registries was also apparent. The results point to local differences in sub-site specific risk factors which might be elucidated by analytical epidemiological assessment.