Hyderabad: The recently released population-based cancer registry for Hyderabad highlights a rise in tobacco-related cancers, including those of the lung, mouth, and tongue.
Meanwhile, doctors from the city have also noticed an increase in lung cancer cases among non-smokers, with air pollution emerging as the major contributing factor. Lung cancer is increasingly being diagnosed in individuals who have never smoked.
"Around 30 per cent of lung cancer patients are non-smokers," said Dr. Sadashivudu Gundeti, head of the medical oncology department at NIMS. He said that this was more due to second-hand smoke, such as exposure from a spouse who smokes or sitting in bars and pub frequented by smokers in urban areas, while it is due to inhaling fire-wood smoke in rural areas.
Air pollution is another major factor. A recent study by the International Agency for Research on Cancer (IARC) found an increase in adenocarcinoma, a subtype of lung cancer typically seen in non-smokers. The study noted a spike in such cases in southeast Asia, particularly in China, and suggested that air pollution might play a significant role in the development of adenocarcinoma. Studies have shown a growing number of lung cancer cases among never-smokers in India.
"Several studies indicate that between 40 per cent and 50 per cent of lung cancer cases in southeast Asia involve non-smokers, with the figure rising to 83 per cent among south Asian women. The contributing factors for lung cancer among non-smokers include air pollution (especially particulate matter PM2.5), which is a major concern in urban areas," explained a study conducted by doctors at Tata Memorial Hospital, Mumbai, and others. This was published in the recent edition of The Lancet.
Medical oncologist Dr. Sainath noted, "While it's difficult to pinpoint specific pollutants or air quality levels that directly cause cancer, exposure to air pollution is certainly a risk factor. Over exposure can create an environment where cancer is more likely to develop. A smoker may develop cancer even 20 years after giving up the habit. Continuous exposure to polluted air can increase the risk as well."
In Hyderabad, air pollution levels have been rising steadily, thereby increasing the risk for lung cancers as well.
As per the National Clean Air Programme (NCAP), the city is among the top three areas in Telangana where pollution control goals (of bringing down AQI levels to below 60) have not been met, and hence the ‘non-attainment city’ label.
Other areas facing similar challenges include Patancheru, Sangareddy, Nalgonda, and the likelihood of Warangal coming into this category.
"The rise in population, vehicles, and construction activities are major contributors to the increasing air pollution in Hyderabad. While Nalgonda's AQI levels have dropped to around 60, Hyderabad's AQI remains at 83," said an official from the Telangana Pollution Control Board.