Prostate cancer can risk of colon cancer: Study

Men with prostate cancer should be especially diligent about having routine screening colonoscopies, results of a new study by gastroenterologists at the University at Buffalo indicate.

Their findings show that persons diagnosed with prostate cancer had significantly more abnormal colon polyps, known as adenomas, and advanced adenomas than men without prostate cancer.

Results of the research were presented Oct. 19 at a 10:30 a.m. session at the American College of Gastroenterology meeting being held Oct. 15-20 in San Antonio, Texas.

While most adenomas are benign and don't become cancerous, there is evidence that most colon cancers begin as adenomas. Advanced adenomas carry an even higher colorectal cancer risk.

"Colon cancer and prostate cancer are two of the most common cancers in males," says Ognian Pomakov, MD, an author on the study. "However there are no published clinical studies to date that determined the prevalence of colorectal neoplasms in people with prostate cancer.

"Our study is the first to show that men with prostate cancer are at increased risk of developing colon cancer, and that it is especially important for these men not skip their routine colonoscopies."

Pomakov is an assistant professor in the Department of Medicine in the UB School of Medicine and Biomedical Sciences and an attending gastroenterologist at the Buffalo VA Medical Center. First author is Madhusudhan Sunkavalli, a UB internal medical resident.

The study involved 2,011 men who had colonoscopies at the Buffalo VAMC. The researchers reviewed patient records, colonoscopy reports and pathology reports, as well as data on the prevalence of adenomas, advanced adenomas, cancerous adenomas and their location within the colon.

The study compared the colonoscopy findings of 188 patients diagnosed with prostate cancer with the rest of the patients, who served as controls. Results showed that prostate cancer patients had significantly higher prevalence of abnormal polyps and advanced adenomas, compared to controls.

Forty-eight percent of prostate cancer patients had adenomas, compared to 30.8 percent of controls, and 15.4 percent had advanced adenomas compared to 10 percent of the men without prostate cancer.

"Our study findings suggest that patients with prostate cancer should definitely get their screening colonoscopy on time," says Pomakov. "In light of the limited resources of health-care systems, a priority should be given to such patients for colonoscopy screening.

"Further larger, and preferably prospective, studies should determine if screening for colorectal cancer should begin earlier than the currently recommended age of 50 for patients with prostate cancer."