Real-Life Experience with Sonidegib for Locally Advanced Basosquamous Carcinoma: A Case Series.

Introduction: Basosquamous carcinoma is an uncommon subtype of basal cell carcinoma (BCC), characterized by aggressive local growth and metastatic potential, that mainly develops on the nose, perinasal area, and ears, representing 1.2-2.7% of all head-neck keratinocyte carcinomas. Although systemic therapy with hedgehog inhibitors (HHIs) represents the first-line medical treatment in advanced BCC, to date, no standard therapy for advanced basosquamous carcinoma has been established. Herein, we reported a case series of patients affected by locally advanced basosquamous carcinomas, who were treated with HHIs.

Case presentation: Data of 5 patients receiving HHIs for locally advanced basosquamous carcinomas were retrieved (2 women and 3 males, age range: 63-89 years, average age of 77 years). Skin lesions were located on the head-neck area; in particular, 4 tumors involved orbital and periorbital area and 1 tumor developed in the retro-auricular region. A clinical response was obtained in 3 out of 5 patients (2 partial responses and 1 complete response), while disease progression was observed in the remaining 2 patients. Hence, therapy was interrupted, switching to surgery or immunotherapy.

Conclusion: Increasing evidence suggests considering HHIs for large skin tumors developing in functionally and cosmetically sensitive areas, in patients with multiple comorbidities, although their use for basosquamous carcinoma require more exploration, large cohort populations, and long follow-up assessment.