While staying out of the warm California sun is still the best way to prevent skin cancer, a new study authored by a Stanford researcher has found that a common arthritis drug similar to aspirin can prevent some of the damage caused by the disease.

According to a study by dermatology Prof. Jean Tang published in Cancer Prevention Research last week, the non-steroidal anti-inflammatory drug (NSAID) celecoxib, also known by its trade name, Celebrex, has been shown to reduce the occurrence of basal cell carcinoma (BCC) in mice and humans. Tang’s study, conducted during her time at UC-San Francisco from 2001 to 2004, involved 60 patients with Gorlin syndrome, a genetic disorder that makes affected individuals particularly prone to developing the most common type of skin cancer in the U.S., BCC.

Half the patients were given a 200-mg celecoxib pill twice a day, the same dose prescribed to treat arthritis and the other half received a placebo. The celecoxib group saw a 50 percent reduction in their tumor count and these results persisted one year after treatment stopped.

“It seemed like some of the tumors didn’t grow as big, or some of the tumors shrank significantly,” Tang said.

BCCs present as a new bump or growth and arise from the top layer of the skin. These tumors commonly occur on the face and neck, areas that undergo frequent sun exposure. Caucasians and those in sunny areas like California are particularly susceptible to developing BCCs: one in five Caucasians living in California will develop a BCC in their lifetime, according to Tang.

Celecoxib works to prevent or slow cancer growth by inhibiting the enzyme cyclooxygenase, which causes tissue inflammation and is one of the many mechanisms behind BCC tumor development. Previous studies have also shown that celecoxib can reduce the incidence of cancers associated with chronic inflammation, such as colon cancer and squamous cell carcinoma (another type of skin cancer) in groups genetically predisposed to these diseases.

Well over one million cases of BCC are diagnosed annually in the U.S., said dermatology Prof. Susan Swetter, who was not involved in the study.  While BCCs are not associated with a tendency to spread to other organs or cause cancer mortality and can be cured by surgical removal, this and other treatments can cause significant disfigurement and discomfort, she added. Recovery time is also an issue, as is cost.

“The economic cost of treating non-melanoma skin cancer is enormous, with an annual estimated cost of $2.5 billion in the U.S.,” Swetter said.

While celecoxib has been FDA approved and spent over a decade on the market, Tang warns against applying the results of this study to people who only have a few BCCs, since this study only tested celecoxib’s effects on Gorlin syndrome patients, who have hundreds of BCCs.

“A lot of people might ask me, ‘Gosh, the majority of BCC tumors occur in healthy patients who are non-Gorlins — would this drug work for patients with one or two BCC tumors?’” Tang said. “We don’t know that because we didn’t test that group.”

Celecoxib has also been associated with various side effects ranging from stomach ulcers to increased risk of cardiovascular disease. The increase in the occurrence of cardiovascular disease in patients taking these drugs prompted a 2003 recall of Vioxx and Bextra, NSAID drugs that are chemically similar to celecoxib. Tang had a study halted in the midst of the recall, though her patients only reported mild stomach upset.

“A lot of that work has been frozen due to [this type of drug’s] effects on cardiovascular disease,” Tang said. “Here, we show another cancer that can be reduced again with celecoxib and we’re hoping that there’s a renewed interest in this class of molecules.”

Tang also plans to study the possibility of administering celecoxib topically, by rubbing it onto skin, to reduce the risk of cardiovascular toxicity that occurs when the drug is taken orally.

Swetter said that Tang’s research is taking place within an emerging field.

“The field of cancer chemoprevention, i.e. preventing cancer at the outset in at-risk individuals, is still relatively young,” Swetter said. “Studies such as Dr. Tang’s do a great deal to advance our knowledge.”