Effect of Field Treatment of Actinic Keratosis With Ingenol Mebutate Gel on the Identification of Lesions for Biopsy.

Actinic keratoses (AKs) are premalignant skin lesions caused by cumulative ultraviolet-light exposure that may progress to invasive squamous cell carcinoma (SCC). As the clinical presentation of AKs varies widely, only a histopathologic analysis of a biopsied sample can eliminate or confirm a diagnosis of invasive SCC. Reducing the burden of AK with a combination of lesion-directed and field-directed treatments may help to identify persistent, suspicious lesions that require further evaluation. We present 10 cases of SCC that were identified and histologically confirmed in 7 patients after complete or substantial clearance of AKs by sequential treatment of sun-damaged skin with cryosurgery and ingenol mebutate.