New Delhi, Nov. 11: The ban on public smoking is likely to have only a limited impact in the country on tobacco-related cancers which are primarily driven by tobacco chewing, a senior oncologist has said.

Although smoking can cause cancers of the lung, larynx and oesophagus, cancer registry figures suggest oral cancer, which is associated with tobacco chewing, accounts for the majority of tobacco-related cancers in the country, said Pankaj Chaturvedi, a surgeon at Mumbai’s Tata Memorial Hospital.

“About 60 to 70 per cent of India’s estimated 250-million tobacco users chew tobacco,” Chaturvedi said at a conference organised by the health ministry to devise strategies to address the problem of smokeless tobacco. “The ban on smoking deals with only about one-third of tobacco users.”

Data from cancer registries maintained by the Indian Council of Medical Research point to oral cancer incidence of 50 new cases per 100,000 population each year, Chaturvedi said. In contrast, the incidence of lung cancer is about 18 per 100,000, while cancers of the pharynx and oesophagus account for about 10 per 100,000.

Health activists who have been spearheading the campaign against public smoking have called for fresh initiatives against the tobacco chewing habit. “Smoking is also related to heart and lung disease. But action to curb chewing will be equally important,” said Prakash Gupta, a cancer epidemiologist in Mumbai.

Most patients with oral cancer in India seek medical treatment in the advanced stages of the disease when it becomes difficult to cure. About 50 per cent of oral cancer patients die within a year of diagnosis, Chaturvedi said.

The health ministry has just launched a media campaign on oral cancer, using examples of patients from the Tata hospital in an effort to highlight the consequences of smokeless tobacco.