Population-based study of incidence trends of cutaneous squamous cell carcinoma, carcinoma in situ, and keratoacanthoma by sex, age, and anatomical site

Cutaneous squamous cell carcinoma (cSCC), cSCC in situ (CIS), and keratoacanthoma (KA) pose growing public health chalennges due to their associated morbidity, health care burden, and costs. There is a need for systematic registration of these frequent neoplasms. A nationwide, population-based cohort study in Denmark investigated incidence trends of these keratinocyte neoplasms. The study included 109,787 cases (2005-2023) in 95,352 individuals aged 20 years or older. The incidence of cSCC and CIS increased, whereas incidence of KA declined. Male individuals experienced more tumors on the face, scalp, and neck, while female individuals exhibited more on the leggs. Incidence rates in younger female individuals aged 40 to 59 years exceeded those in male individuals. The authors conclude that the high and rising incidence of cSCC and CIS, together with a shifting burden of keratinocyte neoplasms across age, sex, and anatomical site, highlight the need for surveillance and targeted, person-centered dermatologic care.