Oncologist. 2020 Oct 5. doi: 10.1002/onco.13552. Online ahead of print.
Fibroblast growth factor receptor (FGFR) tyrosine kinases, which are expressed on the cell membrane, are involved in a wide range of biological functions such as cell proliferation, survival, migration, and differentiation. The identification of FGFR fusions and other alterations in a wide range of solid tumors, including cholangiocarcinoma and bladder cancer, has resulted in the development of several selective FGFR inhibitors for use in these indications, for example infigratinib, erdafitinib,
derazantinib, pemigatinib, and futibatinib. In addition to the typical adverse events associated with tyrosine kinases, the FGFR inhibitors appear to give rise to a number of adverse events affecting the skin. Here we describe these skin events, which include the more common nail adverse events (e.g., onycholysis), palmar-plantar erythrodysesthesia syndrome, and stomatitis, as well as less common reactions such as calciphylaxis. This review aims to provide oncologists with an understanding of these dermatologic events and proposes guidelines for the management of treatment-emergent dermatologic adverse events. Awareness of possible adverse events associated with specific drugs should allow physicians to educate patients as to what to expect and implement effective management plans at the earliest possible opportunity, thereby preventing premature discontinuation while maintaining patient quality of life. IMPLICATIONS FOR PRACTICE: Identification of FGFR aberrations in cancers such as cholangiocarcinoma and bladder cancer led to development of selective FGFR inhibitors for these indications, based on clinical benefit and safety profiles. The most frequent adverse events (AEs) include those affecting the skin, hair, and nails, a unique class effect of these agents. These are usually mild to moderate in severity. We reviewed skin AEs reported with FGFR inhibitors and provide management and supportive care guidelines for physicians, aiming to increase awareness of skin events in clinical practice and provide practical guidance on the most effective treatment strategies. Early intervention and effective management may improve treatment adherence, optimize outcomes, and improve patient quality of life.