Nivolumab in platinum-refractory head-and-neck cancers: A retrospective observational audit from a tertiary cancer center

Abstract

ABSTRACT Background: Nivolumab and pembrolizumab are approved treatment options for platinum-refractory head-and-neck squamous cell cancer (HNSCC) based on the demonstration of improved outcomes in clinical trials. However, limited data exist on their efficacy in the real-world setting. Objectives: To determine the impact of immune checkpoint inhibitors in the treatment of platinum-refractory HNSCC and the associated outcomes in a real-world setting. Materials and Methods: This was a retrospective study conducted between August 1, 2016, and December 31, 2018 in the Department of Medical Oncology at the Tata Memorial Hospital, a tertiary cancer center in India. We included patients with advanced platinum refractory HNSCC who had been treated with nivolumab. Data regarding adverse events, response, overall survival (OS), and progression-free survival (PFS) were collected. Survival analysis was performed by the Kaplan–Meier method. Cox regression analysis was used to identify the factors which affected OS. Results: A total of 2796 patients qualified for potential treatment with immunotherapy, but only 41 (1.47%) were able to receive it. The dose used was 240 mg in seven patients (17.1%) and 3 mg/kg in the remaining 34 (82.9%). The response rate was 19.5% (n = 8). The median PFS and OS were 2.27 months [95% confidence interval (CI), 1.51–4.14] and 5.29 months [95% CI, 3.78–11.67], respectively. The 1 year OS was 33.6% (95% CI, 19.5–48.4). Oral cavity tumors were associated with a lower PFS (hazard ratio, 3.86; 95% CI, 1.67–8.92; P = 0.001) and OS (hazard ratio, 2.79; 95% CI, 1.26–6.17; P = 0.001). Conclusion: Nivolumab has a good impact on both OS and PFS even in the real-world setting of patients with extensively pretreated platinum-refractory HNSCC similar to what has been reported in the pivotal studies. Among the patients who are treated with nivolumab, those with oral cavity tumors have a worse OS and PFS relative to those of other sites. This hypothesis-generating observation requires further investigation.