Vismodegib-Induced Alopecia: Trichoscopic and Confocal Microscopy Evaluation

Introduction: Vismodegib is the first-in-class inhibitor of the sonic hedgehog pathway useful in the treatment of locally advanced or metastatic basal cell carcinoma (BCC) that is not amenable to surgery and radiation therapy. Common adverse events of vismodegib, probably mechanism related, include alopecia (58%) as a reversible side effect. Case Presentation: We report 2 cases of patients receiving vismodegib for the treatment of locally advanced BCCs that developed alopecia during treatment and describe clinical, dermoscopic, and reflectance confocal microscopy (RCM) features of this adverse event. Conclusion: Alopecia is one of the most distressing adverse events leading to vismodegib discontinuations. To our knowledge, these are the first descriptions of RCM dermoscopy in vismodegib-induced alopecia. Trichoscopy and confocal microscopy are essential to monitoring vismodegib hair loss and the response to the treatment.