Hyperprogressive disease and its clinical impact in patients with recurrent and/or metastatic head and neck squamous cell carcinoma treated with immune-checkpoint inhibitors: Korean cancer study group HN 18-12.

Younger patients with oral cavity cancer or prior treatment with locoregional radiotherapy could be regarded potential risk groups for HPD in patients with R/M-HNSCC treated with ICIs. Although HPD could consistently predict poorer survival outcomes, patients who experienced HPD with ICIs should not be excluded from the subsequent salvage chemotherapy treatments.