A Practical Guide for the Follow-Up of Patients with Advanced Basal Cell Carcinoma During Treatment with Hedgehog Pathway Inhibitors

The Hedgehog pathway inhibitors (HPIs), vismodegib and sonidegib, are increasingly employed in the treatment of patients with advanced basal cell carcinoma (BCC). The aim of this review is to create a synthesis of available information in the literature regarding the follow-up of patients with advanced BCC treated with HPIs and to provide the treating physician with a structured practical guide to standardize clinical practice. Several challenges during treatment are addressed: to optimally evaluate tumor responses, to differentiate between resistance (HPI rechallenge not possible) and recurrence (HPI rechallenge may be possible) in case of BCC regrowth, to readily assess for toxicity and tolerability issues, to provide patients with practical ways and behaviors to effectively cope with adverse events, and to improve patient adherence and quality of life. Implications for Practice This is a practical guide for clinical practice regarding the monitoring and follow-up of patients with advanced basal cell carcinoma (BCC) during treatment with the Hedgehog pathway inhibitors (HPIs) vismodegib and sonidegib. This review aims to bridge the gap in knowledge of assessing tumor response for BCC with both an externally visible component and an infiltrating component measurable with imaging. Furthermore, it addresses the follow-up for adverse events as a challenging multistep process involving practices aiming to readily assess new-onset symptoms of HPI toxicity, perform total-body skin examination, and improve patient adherence and quality of life.