Janus Kinase Inhibitors and Non-Melanoma Skin Cancer.

OPINION STATEMENT: JAK (janus kinase) inhibitors are becoming increasingly prescribed for various conditions from dermatologic diseases to graft versus host disease in bone marrow transplant recipients. This class of drugs has been found to be truly life-changing for many, though they are not without potential adverse effects. While JAK inhibitors have not been shown to significantly increase the risk of non-melanoma skin cancer (NMSC) in large scale clinical trials, NMSC is one of the most concerning possible adverse events, and there have been several reported cases of aggressive squamous cell carcinomas, especially in our already immunosuppressed patient populations. In these patients, it is incredibly important that patients are on the lowest possible dosage of the JAK inhibitor. In addition, these patients must be routinely screened by a dermatologist with a comprehensive skin exam to ensure early detection if skin cancer was to develop. For those patients diagnosed with skin cancer, early intervention is key to optimize outcomes, and at times, multi-disciplinary care coordination is needed. In the future, large-scale studies with longer follow-up of patients would help determine whether JAK inhibitors significantly increase the risk of NMSC.