Unexpected response with palliative conventional therapy in head and neck squamous cell carcinoma after anti-programmed death-1 progression.

Abstract

The application of anti-programmed death-1 (PD-1) therapies for recurrent or metastatic head and neck squamous cell carcinoma (HNSCC) has found promising results. It is the first "second-line therapy" in this setting to impact on prognosis. The studies demonstrated overall response rates in the range of 20%. Therefore, HNSCC showed 60%-80% progression at first evaluation with better overall survival, suggesting regained efficacy of treatments given thereafter. We report three clinical cases treated with anti-PD-1 after platinum-based chemotherapy. Our case reports achieved an unforeseen response to conventional therapies supporting the hypothesis of restored responses to conventional therapies after immunotherapy. We believe that the inhibition of the PD-1/PD-ligand 1 checkpoint may synergize with both chemotherapy or radiotherapy through immunologic interplay, reversing the HNSCC-induced immune suppression.