Men treated with hormone-based therapy for prostate cancer faced a 30 percent to 40 percent higher risk of colorectal cancer, compared to patients who did not receive this treatment, says a new study.
The first study of its kind looked at use of androgen deprivation therapy, a common type of treatment for prostate cancer that involves blocking the male hormone testosterone through either surgical removal of the testicles or a series of injections.
Researchers looked at data from 107,859 men aged 67 and older with prostate cancer, identified through the Surveillance, Epidemiology and End Results and Medicare linked database, which provides information about older adults with newly diagnosed cancer.
The researchers found that the risk increased the longer a man received androgen deprivation therapy. Patients who had their testicles removed, a procedure called orchiectomy, had the highest rates of colorectal cancer.
Results of the study were published online in the Journal of the National Cancer Institute.