Cryosurgery followed by topical ingenol mebutate cleared extensive regions of actinic keratosis, which helped reveal residual squamous cell carcinomas, according to a report in the August issue of the Journal of Drugs in Dermatology.
The findings show that ingenol mebutate can clear multiple AKs and reduce the number of scarring biopsies required to identify SCCs, said Dr. Miriam S. Bettencourt, a dermatologist in group practice in Henderson, Nev. “In our dermatology clinic, many of the patients with a long history of AK who were treated with ingenol mebutate used sequentially after cryosurgery have achieved complete or partial clearance of AKs.”
Ingenol mebutate gel after cryosurgery cleared AKs more effectively than cryosurgery alone in a recent phase III trial (J Drugs Dermatol. 2014 Jun;13741-7), Dr. Bettencourt noted. She described six men and one woman who each had at least 10 recurrent or hyperkeratotic AKs and previously had undergone cryosurgery. She treated all patients with cryosurgery, followed 2 weeks later by two or three once-daily applications of ingenol mebutate gel at strengths of 0.05% or 0.015%, respectively (J Drugs Dermatol. 2015 Aug;14;813-8). One course of ingenol mebutate gel cleared 50%-100% of AKs, Dr. Bettencourt said. She treated residual AKs with cryosurgery, and five patients also received at least one more course of ingenol mebutate to re-treat a partially cleared area or to treat a separate area. Shave biopsies of 10 residual suspicious lesions taken 3-8 months later all revealed invasive SCCs, which were treated with Mohs micrographic surgery (MMS). “These lesions may have been preexisting at the time of topical treatment but not readily recognized as suspicious in the heavily actinically damaged skin, in which suspected or small SCCs may be adjacent to or obscured by AKs,” she said. “Alternatively, these tumors may have been spontaneous new SCCs. In either case, we suggest that effective clearance of AKs from the palette of sun-damaged skin with ingenol mebutate permitted prompt recognition of these lesions as suspicious, and led to further diagnosis and treatment with MMS.”
All patients developed mild to moderate localized redness, flaking, and crusting starting on the second day of ingenol mebutate treatment and resolving within a week of finishing the course, Dr. Bettencourt said.
She reported that she had no relevant financial conflicts.