Smoking lowers chances of surviving throat cancer

For people with cancer of the larynx or lower pharynx, continuing to smoke or drink alcohol make it less likely that they'll survive, while eating a diet rich in vegetables and vitamin C improves their survival, a new study shows.

"One might think, now I that have cancer, what's the point of stopping smoking? But there is clearly a benefit in doing that; it will improve your survival," said Dr. Rajesh P. Dikshit.

Tobacco smoking, alcohol drinking, and diet have all been linked to the development of cancer in the larynx, or voicebox, and the area immediately above it at the back of the throat, the hypopharynx. However, little was known about the role of these risk factors on the survival of patients with these cancers.

Dikshit, working for the International Agency for Research on Cancer in Lyon, France, and his colleagues conducted a study to analyze the survival of patients with laryngeal and hypopharyngeal cancer. They followed 931 patients who had enrolled in a previous cancer study that had started in the early 80s, and analyzed the role of tobacco, alcohol and diet on cancer outcome in these patients for up to 21 years.

As they report in the International Journal of Cancer, the investigators found that smoking was the most important factor adversely affecting the patient's survival, particularly in those patients with tumors in the larynx.

"This is a very important finding," Dikshit told Reuters Health. "We knew that smoking is a cause of laryngeal and hypopharyngeal cancer, but now it's clear that it affects survival as well." Alcohol consumption also had a negative effect on survival, but to a lesser extent than tobacco.

But the most important result, Dikshit remarked, was the protective effect of some diet components. "We found that a high intake of vitamin C significantly improved the patients' survival."

The investigators also found a strong protective effect of a diet rich in vegetables, but not of the individual components found in those vegetables. Only vitamin C was protective on its own.

"The message here is that it is very important to stop smoking even after developing laryngeal and hypopharyngeal cancer," Dikshit said.

Eating vegetables and vitamin C is also something cancer patients should consider. "Doctors are prescribing this already, but now we have demonstrated that these diet components improve the patient's survival, and perhaps make the treatment more effective."

SOURCE: International Journal of Cancer, December 2005