Parts of India have the world's highest incidence of cancers of the gall bladder, mouth, and lower pharynx, India's first cancer atlas shows.
Figure 1.
The atlas, produced by the Indian Council of Medical Research, has also found pockets of stomach and thyroid cancer in the south of the country.
The National Cancer Registry Programme in Bangalore used data from 105 hospitals and private clinics in 82 of the 593 districts in India to map the incidence of cancer, as part of a project funded by the World Health Organization.
The survey included more than 200 000 patients with histopathologically confirmed cancers, whose details were sent to the registry through the internet.
Previously, the registry, which was launched in 1981, had covered just a few cities and a single village and had relied on hospital records and death certificates to estimate the burden of cancer. It used to take up to five years to submit the information. Data analysis for the atlas took just 15 months.
The atlas, scheduled for release by the health ministry within the next few weeks, indicates that the age adjusted incidence of gall bladder cancer in women in New Delhi is 10.6 per 100 000 of the population—the world's highest rate for women for this cancer.
Districts in central, south, and northeast India had the world's highest incidence of cancers associated with tobacco, which is chewed as well as smoked in India. Aizawl district in the northeastern state of Mizoram has the world's highest incidence of cancers in men of the lower pharynx (11.5 per 100 000 people) and tongue (7.6 per 100 000 people), the atlas shows. The district also has the country's highest rate of stomach cancer among men.
The incidence of mouth cancer among men in Pondicherry was 8.9 per 100 000, one of the highest rates in the world for men. Rates of stomach cancer were high among men in Bangalore and Chennai.
“These findings will give us a better picture of realities [on the ground] and help [us to make] wiser resource allocation,” said Dr Purvish Parikh, head of medical oncology at the Tata Memorial Hospital in Mumbai. Cancer epidemiologists have long been concerned that diagnostic services for cancer are inadequate in many parts of India.
The survey also detected “a belt of thyroid cancer” in women in coastal districts of Kerala, Karnataka, and Goa. The findings are expected to stimulate research to identify risk factors at specific locations.
“[Lower] pharynx cancer may be linked to tobacco use, but we're going to explore the genetic components of stomach cancer,” said Dr Eric Zomawia, pathologist at the Government Hospital in Aizawl and collaborator on the project.
The incidence atlas also confirmed earlier observations that breast cancer has replaced cervical cancer as the leading site of cancer among women in Indian cities and that lung cancer is the most common cancer in men in Calcutta, Mumbai, and New Delhi.