Colonoscopy lowers cancer risk in colitis patients

NEW YORK, July 8 (Reuters) Regular colonoscopy with follow-up treatment if needed can help prevent colon cancer in patients with ulcerative colitis, new research suggests. Likewise, the use of anti-inflammatory drugs, such as aspirin and ibuprofen, seems to reduce the risk as well.

By contrast, the presence of ''pseudopolyps'' in the colon seems to raise the risk of cancer.

Ulcerative colitis is one of two principal inflammatory bowel diseases, the other one being Crohn's disease. With the disease, severe inflammation can occur throughout the colon (also called the large intestine) resulting in pain and bloody diarrhea. Pseudopolyps, a common occurrence with the disease, look like real polyps, but are actually the result of inflammation that surrounds a small portion of intestine.

People with ulcerative colitis are known to be at increased risk for colon cancer and the only way to completely eliminate this risk is to remove the colon and rectum, an operation that most patients want to avoid. Thus, there is a need to identify risk factors for colon cancer in such patients to prevent the disease or at least diagnosis it at an early, treatable stage.

There are limited data regarding the risk factors for colorectal cancer in ulcerative colitis patients, Dr Edward V Loftus, from the Mayo Clinic in Rochester, Minnesota, and colleagues note in the journal Gastroenterology. Regular colonoscopy and a commonly used drug called 5-ASA could potentially reduce the risk, but these two factors have never been investigated in the same study.

The researchers assessed risk factors for colorectal cancer by analysing data from 188 ulcerative colitis patients with the cancer and 188 similar patients without it.

A history of pseudopolyps was tied to a 2.5-fold increased risk of colorectal cancer, the report indicates.

Most of the other factors studied had the opposite effect.

Surveillance colonoscopy, smoking, and use of steroids, aspirin, NSAIDs (ibuprofen, etc), and 5-ASA all seemed to protect against colon cancer with risk reductions ranging from 50 to 90 percent. After 5 years, however, 5-ASA use was no longer significantly linked to a reduced risk.

Previous reports have also suggested that NSAIDs, steroids and smoking have protective effects against ulcerative colitis-related cancer. The common reason appears to be that each has anti-inflammatory effects that reduce the risk of cancer.

''These results suggest that, in a population matched for extent and duration of chronic ulcerative colitis, surveillance colonoscopy and use of anti-inflammatory medications may reduce the risk of cancer,'' the authors conclude.

REUTERS KD DS1117