Thiopurines and non-melanoma skin cancer: partners in crime in inflammatory bowel diseases

Introduction: Several studies have shown that inflammatory bowel diseases (IBD) patients treated with thiopurines have an increased risk of developing skin cancer. Sources of data: This review is based on recent published literature regarding the use of thiopurines in IBD and skin malignancies. Areas of agreement: Exposure to thiopurines is significantly associated with nonmelanoma skin cancer, but not with melanoma. Primary and secondary prevention including sun-protective measures and regular dermatologic screening are recommended in IBD patients, particularly in those exposed to thiopurines. Areas of controversy: Both when and how immunosuppressive therapy should be resumed in patients with a prior history of skin cancer still remain debatable topics. Growing points: The benefit-risk balance between thiopurine therapy and risk of skin cancer should be evaluated in the drug decision process. Areas timely for developing research: The approval of new effective strategies requires the re-evaluation of the positioning of thiopurines within the therapeutic algorithm based on an increasingly individualized approach.