IBD May Increase Skin Cancer Risk

Inflammatory bowel disease (IBD) may increase skin cancer risks according to two emerging studies.

The two studies revealed that some IBD patients are at increased risk for skin cancer and that these risks significantly increase when a popular class of drugs to treat IBD—thiopurines—are taken said DailyRx. Thiorpurines are immunosuppressants sold under brands including Purinethol (6-mercatopurine), Azasan and Imuran (azathioprine), and Tabloid and Tioguanine (6-thioguanine).

According to the first study, thiopurine exposure increased risks for nonmelanoma skin cancer (NMSC) in IBD patients, including patients under the age of 50, said DailyRx. NMSC is the most common form of cancer diagnosed in the United States and is often diagnosed in patients taking immunosuppressives, which are being prescribed more and more for IBD.

Nonmelanoma skin cancers include squamous cell and basal cell cancers, which are diagnosed in about one million Americans annually and have a very high cure rate with early detection.

The second study found that certain patients, including male Crohn’s disease patients, suffered increased risks for basal cell carcinoma (BCC) and that, in this group, patients taking thiopurines suffered increased risks for squamous cell carcinoma (SCC), said DailyRx. Study lead, Harminder Singh, M.D., of the University of Manitoba, says that IBD patients should protect themselves from skin cancer and that their physicians “need to be extra vigilant about skin care”, specifically with those taking immunosuppressants, including thiopurines, wrote Daily RX. Both studies appear in the Gastroenterology, the official journal of the American Gastroenterological Association.

In the past, IBD included ulcerative colitis and Crohn’s disease, with the differences based on the different gastrointestinal tract areas involved; however, both involve chronic inflammation leading to diarrhea, rectal bleeding, and abdominal cramps. There is no cure for IBD and its cause remains unknown, but experts believe the disease is connected to an inappropriate immune system response. IBD medications generally work to reduce immune system activity.

At the recent American College of Gastroenterology’s annual meeting in San Diego, California, Millie Long, MD MPH, and researchers from the University of North Carolina, Chapel Hill, said the issue is likely connected to IBD medicines, with some drugs riskier than others. ”Patients on immunosuppressant medications, particularly of the thiopurine class, have an increased risk of skin cancer, greater than three times, compared to patients with IBD who do not use these medications,” Long told WebMD.

Long-term use of at least one year increased the risks for IBD with those on long-term thiopurines experiencing a four-fold increased risk, and Crohn’s patients on long-term biologics experiencing a two-fold increased risk of skin cancer, according to Long and her team.

Meanwhile, we recently wrote about another study in which a connection with how hormone replacement therapy (HRT) is linked to skin cancer