WEDNESDAY, Feb. 12, 2025 -- Use of immune checkpoint inhibitors (ICIs) for any cancer is associated with a significant reduction in actinic keratoses (AKs), according to a study published online Feb. 12 in JAMA Dermatology.

Charlotte Cox, M.D., from the University of Queensland in Brisbane, Australia, and colleagues conducted a prospective cohort study to examine the association of ICIs with changes in field cancerization assessed by the number of AKs and keratinocyte carcinomas (KCs) at baseline versus 12 months after starting ICI therapy. Consecutive immunocompetent adults starting therapy with an inhibitor for programmed cell death 1 or programmed cell death ligand 1 for any active cancer with clinical AKs on their forearms were eligible; 23 participants were recruited, four of whom died due to disease progression.

The researchers observed a significant decrease in the mean AK number, from 47.2 at baseline to 14.3 at 12 months. The likelihood of having a 65 percent or greater reduction in AK numbers was increased for younger patients and those with a history of blistering sunburn. In the 12 months before to the 12 months after starting ICI therapy, KC total numbers decreased from 42 to 17. In the same period, the number of cutaneous squamous cell carcinomas decreased from 16 to five.

"This pilot cohort study highlights the potential association of ICI therapy, originally used in cancer treatment, with significant reduction of clinical AKs," the authors write. "However, the observed reduction in cutaneous squamous cell carcinomas occurrence was not statistically significant."

Several authors disclosed ties to the pharmaceutical and skin care industries.