Keratotic Skin Lesions and Other Risk Factors Are Associated with Skin Cancer in Organ-Transplant Recipients: A Case–Control Study in The Netherlands, United Kingdom, Germany, France, and Italy

Abstract

This study examines the association of keratotic skin lesions with the development of skin cancer in 915 solid organ-transplant recipients in five European countries. In a hospital-based case-control study, cases with squamous- and basal-cell carcinoma were compared with controls without skin cancer. Questionnaires, scrutiny of medical charts, and skin examination were delivered according to a standardized protocol. Keratotic skin lesions and viral warts were counted on different body sites. Keratotic skin lesions were strongly associated with an increased risk of squamous-cell carcinoma, with adjusted odds ratios of 4.1 (2.4;7.0) and 12.1 (6.1;24) for 1-49 and 50 and more keratotic skin lesions compared with no lesions, respectively. Keratotic skin lesions were also associated with basal-cell carcinoma with adjusted odds ratios of 2.9 (1.7;4.9) and 4.0 (1.7;9.2) for 1-49 and 50 and more lesions, respectively. Lighter skin types and painful sunburns were also significantly associated with an increased risk of squamous- and basal-cell carcinoma. Keratotic skin lesions are strongly associated with skin cancer and are, thus, an important clinical criterion for identifying those organ-transplant recipients at an increased risk of skin cancers who should be offered more intensive skin surveillance.