Actinic keratosis as a marker of field cancerization in excision specimens of cutaneous malignancies.

Field cancerization is the process in which a singular cell accumulates genetic mutations following carcinogen exposure and then divides to create a "field" of monoclonal premalignant cells. In this study, microscopically identified actinic keratoses (AKs) were used as markers of field cancerization in all excision specimens of squamous cell carcinomas (SCCs), basal cell carcinomas (BCCs), and malignant melanomas (MMs) received by our institution's dermatopathology department over a 3- to 6-month period. Our findings provide additional evidence for the theory of field cancerization, its association with cutaneous malignancies, and the need to assess the extent of field damage when determining treatment strategies.