Kicking Cancer by Kicking the Habit

Prostate cancer patients treated with radiation who smoked had higher recurrence rates and more side effects

(RxWiki News) Quitting smoking may benefit more than just the lungs of prostate cancer patients. It may improve the course of their treatment.

A new study found that patients with prostate cancer who were smokers had an increased risk of having their cancer recur or spread. Current and past smokers had more side effects from radiation treatment for their cancer.

"Upwards of 50% of smokers with cancer continue to smoke after their diagnosis," said lead study author Michael J. Zelefsky, MD, of the Memorial Sloan Kettering Cancer Center in New York City, in an interview with dailyRx News.

Dr. Zelefsky continued, "Given the increased risk of prostate cancer progression and radiation toxicity among smokers, a stronger emphasis on smoking cessation is clearly appropriate."

Dr. Zelefsky and colleagues posed several reasons why smoking may be tied to these increased risks, but their study did not look into the direct effects of smoking on prostate cancer or its treatment.

"We must be cautious not to over-interpret the data," said Alexander Kutikov, MD, a surgical oncologist at the Fox Chase Cancer Center in Philadelphia, in an interview with dailyRx News. "Correlation does not always mean causality."

Dr. Zelefsky and team studied more than 2,300 prostate cancer patients. Cancer of the prostate affects the gland behind the bladder found in men — a gland that makes some of the cells that produce semen, the fluid that carries sperm.

All of these patients had been treated with radiation for their prostate cancer. These researchers collected health data on these patients for around eight years.

These researchers put the patients into categories according to their smoking history — as never smokers, current smokers, former smokers and current smoking unknown.

Dr. Zelefsky and colleagues found an increase in the risk of cancer coming back in patients who smoked — compared to past smokers and nonsmokers. Nonsmokers had about a 66 percent chance of having no recurrence in 10 years — compared to a 63 percent chance in past smokers and a 52 percent chance in current smokers.

Patients with prostate cancer who smoked had more than twice the chance of having the cancer spread or of dying of their disease compared to former smokers and nonsmokers.

Current and past smokers experienced more side effects from their radiation treatment than nonsmokers. Most of the side effects were in the urinary tract and ranged from loss of control of urination to bleeding from the bladder.

Dr. Zelefsky and team felt that smoking may change some biochemical processes in the body, which might interfere with the effectiveness of cancer therapy.

"Smoking certainly may predispose patients to a more aggressive tumor [type]," or to cancer that is not discovered until it is at an advanced stage, Dr. Kutikov said.

Dr. Kutikov continued, "The question of whether smoking status is a truly modifiable risk factor for patients diagnosed with prostate cancer remains to be answered."

This study was published online Jan. 27 in BJU International.

Dr. Zelefsky and team did not disclose any funding sources or conflicts of interest.

Review Date: 
January 25, 2015