In the journals
A prescription cream called 5-fluorouracil (5-FU, sold as Adrucil and other brands) may help people reduce their risk for squamous cell carcinoma (SCC), according to a study published in the Jan. 3, 2017, JAMA Dermatology. SCC, the second most common cancer in the United States, strikes twice as many men as women.
Researchers recruited 932 people, 98% of whom were men, with an average age of 71. Each had experienced at least two skin cancers — SCC, basal cell carcinoma (BCC, the most common skin cancer), or both — on their face or ears within the past five years. They were randomly assigned to receive either the 5-FU cream or a placebo cream. Everyone applied a thin layer twice a day to their face and ears for up to four weeks. Over the course of a year, the 5-FU group had a 75% lower incidence of SCC compared with the placebo group. They also had a 11% lower incidence of BCC, but this difference was not statistically significant. It's not known why 5-FU helped prevent SCC but not BCC, according to the researchers.
5-FU's protective effect only lasted a year, as there was no significant reduction in cancers at later follow-ups. Still, the results show promise, since only two to four weeks of treatment offered a year's protection. Other medications to protect people at high risk for SCC have to be used continuously and stop working once the treatment ends.