Researchers have found that men who undergo external beam radiation for localized prostate cancer may be at a slightly increased risk of developing other cancers.

This findings may help men when trying to decide which treatment would be the best for their prostate cancer.

There has been seen an increased risk for lung, bladder and rectal cancer among patients treated with external beam radiation for prostate cancer but in absolute terms, the absolute risk associated with the development of secondary malignancies in patients exposed to external beam radiation therapy is quite small, said of the researchers.

Patients having to undergo treatment for prostate cancer can decide between surgical removal of the prostate, called radical prostatectomy; implanted radioactive seeds that deliver radiation specifically to the prostate gland; and external beam radiation, which is a non-surgical procedure that delivers radiation to the prostate from outside the body.
External beam radiation was found to be a better treatment choice for older patients rather than younger patients with longer life expectancies, who may be at risk for developing these secondary cancers.

Data on over 10,000 men who were treated for localized prostate cancer has been gathered. Among these men, 6,196 had their prostate surgically removed, and 4,137 underwent external beam radiation. They were then followed and checked for development of bladder, lung and rectal cancer to see which treatment was more likely to increase the risk of these malignancies.

The study found that men who'd undergone external beam radiation had a threefold increased rate of bladder cancer, a 1.8-fold increased rate of lung cancer, and a 1.7-fold increased rate of colorectal cancer in comparison to those men who underwent radical prostatectomy.

The researchers could not explain why external beam radiation would increase the chances of these cancers, especially lung cancer. However, the increased risk for bladder and colorectal cancers was easier to understand as these organs are closer to the prostate.

The researchers reported that it's important to allow prostate cancer patients a few treatment options because not all may be good surgical candidates and may actually lean toward external beam radiotherapy.