May 4, 2004 - Millions of people who take immune system-suppressing steroids like prednisone to treat a wide range of inflammatory diseases may be at increased risk for developing certain cancers. New research supports earlier reports linking steroid use to nonmelanoma-type skin malignancies and non-Hodgkin's lymphoma.
The risk of developing non-Hodgkin's lymphoma or a form of skin cancer called squamous cell carcinoma was roughly two-and-a-half times greater than normal for people who reported long-term use of steroids in the Danish study. Long-term steroid use was associated with a 50% increased risk for developing basal cell carcinoma.
"We have known that immunosuppressive therapy increases the risk for these cancers in (organ) transplant recipients, but these patients are treated with other, more potent immune system-suppressing drugs," lead researcher Henrik Toft Sorensen, MD, PhD, tells WebMD. "The risk associated with [steroid] use alone has not been clear."
Squamous cell and basal cell carcinomas are the most common forms of skin cancer, with at least 1 million cases identified each year in the U.S. Both cancers are slow growing and easily treated, unlike melanoma, which accounts for just 5% of all skin cancers but 75% of deaths from skin cancer in the U.S.
Sorensen and colleagues from Denmark's Aarhus University identified almost 60,000 people enrolled in a prescription database in that country who had filled steroid prescriptions between 1989 and 1996. These data were linked to the comprehensive Danish Cancer Registry. The findings are reported in the May 5 issue of the Journal of the National Cancer Institute.
The researchers found more cases than would have been expected of the two less serious skin cancers, but the increase in melanoma cases was not significant.
Having 15 or more prescriptions for steroids filled over the eight-year period was associated with a 1.52-fold increase in basal cell carcinoma risk and a 2.45-fold increase in risk for squamous cell carcinoma. Non-Hodgkin's lymphoma risk was found to be 2.68-fold higher for patients having 10 to 14 prescriptions filled over the study period.
Skin cancer expert Clark C. Otley, MD, tells WebMD that the risk estimates are almost identical to those seen in another population-based study from the U.S., published in the fall of 2001. In that study, conducted by Dartmouth Medical School researchers, people taking oral steroids like prednisone were found to have a 2.31-fold elevated risk for squamous cell carcinoma and a 1.49-fold elevated risk for basal cell carcinoma.
Otley, who is an assistant professor of dermatology at the Mayo Clinic in Rochester, Minn., says it is now clear that people who take steroids like prednisone should be warned about the risk.
"A person who has severe rheumatoid arthritis or severe asthma needs to be on these medications, but they also need to be very cautious about protecting themselves from the sun," he tells WebMD. "That means using sunscreen regularly; wearing sun-protective clothing, including hats and sunglasses; and avoiding midday sun for extensive outdoor activities."
Experts recommend regular skin checks for skin cancer. Here's what to look for:
In general, skin cancers appear as a change on the skin, like a sore that doesn't heal, a skin irritation that doesn't go away, or a growth on the skin.
Basal cell carcinomas are usually found on the head, neck, back, chest, or shoulders. Squamous cell carcinomas are usually on the face, head, or neck.