Safety and efficacy of cetuximab-containing chemotherapy after immune checkpoint inhibitors for patients with squamous cell carcinoma of the head and neck: a single-center retrospective study.

Immunotherapy has been shown to prolong survival in recurrent or metastatic squamous cell carcinoma of the head and neck (SCCHN) in front-line use; however, subsequent systemic therapy has not been optimized. This study aimed to evaluate the safety and efficacy of cetuximab-containing chemotherapy after immunotherapy. We retrospectively analyzed patients with recurrent or metastatic SCCHN who underwent cetuximab-containing regimens after progression on immunotherapy. Of the 22 patients who met the inclusion criteria, 21 received paclitaxel and cetuximab, and 1 carboplatin and fluorouracil and cetuximab after immunotherapy. Nine patients achieved a partial response, 10 patients had stable disease as their best response on cetuximab-containing chemotherapy, yielding an overall response rate and disease control rate of 40.9 and 86.4%, respectively. The median progression-free survival was 5.2 months, and the median overall survival was 14.5 months. Ten patients developed grade 3-4 adverse events, including neutropenia (31.8%), acneiform rash (9.1%), anemia (4.5%), hypertransaminasemia (4.5%) and stomatitis (4.5%). The most frequent cetuximab-related toxicities across all grades were skin reactions (77.3%), hypomagnesemia (40.9%), stomatitis (27.3%), paronychia (13.6%) and keratitis (4.5%). There was no treatment-related death. Taken together, cetuximab-containing chemotherapy was effective and feasible even after immunotherapy.