Nivolumab in patients with rare head and neck carcinomas: A single center's experience.

Immunotherapy (IO) with anti-PD1 inhibitors is available for the treatment of recurrent/metastatic squamous cell carcinomas of the head and neck (SCCHD) since 2016. Both nivolumab and pembrolizumab were tested in phase 3 randomized trials in adults progressing on or after platinum-based therapy and were found to confer an overall survival benefit compared to investigator's choice. However, very limited data exist concerning IO use in rare subtypes of head and neck carcinoma, like salivary gland carcinoma. We retrospectively collected clinical data of all patients diagnosed with rare subtypes of head and neck carcinoma, who were treated with immune checkpoint inhibitors in our department during the last 5 years. We analyzed safety and efficacy of these therapies. We identified six patients who received nivolumab for recurrent or metastatic head and neck carcinomas, between 31 and 57 years old. All patients had received at least one line of platinum-chemotherapy, as well as radiation therapy. Treatment was administered every 2 weeks, at a dose of 3 mg per kilogram of body weight. Number of nivolumab cycles varied between 2 and 18. Progression-free survival varied from 1 to 12 months and overall survival from 4 to 24 months. Tolerance was very good, except for one case of diabetes and hypothyroidism requiring medication. There is currently insufficient evidence regarding the optimal treatment of the rare non-squamous cell carcinoma of the head and neck. Our case series supports a role for immunotherapy in these patients. However, larger collaborative studies are needed to evaluate this treatment.