Induction Toripalimab and Chemotherapy for Organ Preservation in Locally Advanced Laryngeal and Hypopharyngeal Cancer: A Single-Arm Phase II Clinical Trial

Abstract

Purpose: The aim of this study was to assess the efficacy, toxicities, and potential role of larynx preservation of induction chemotherapy combined with programmed cell death protein 1 (PD-1) inhibitor in locally advanced laryngeal and hypopharyngeal cancer.

Patients and methods: This is a single-arm phase II study. Patients with histopathologically confirmed, resectable locally advanced laryngeal/hypopharyngeal squamous cell carcinoma and Eastern Cooperative Oncology Group Performance Status 0-1 were eligible. Three cycles of induction chemotherapy (paclitaxel 175 mg/m2 d1, cisplatin 25 mg/m2 d1-3) combined with PD-1 inhibitor (toripalimab 240 mg d0) were administered. Response assessment was performed after induction chemoimmunotherapy using RECIST 1.1 criteria. Patients with a complete/partial response of the primary tumor received concurrent chemoradiation, followed by maintenance therapy of toripalimab. Otherwise, patients were referred to surgery, followed by adjuvant (chemo) radiation and maintenance therapy of toripalimab. The primary endpoint is a larynx preservation rate at 3 months postradiation.

Results: Twenty-seven patients were enrolled. Most cases exhibited stage IV disease (81.5%), with T4 representing 37.0%. Five patients underwent pretreatment tracheostomy because of impaired larynx function. Overall response rate of induction chemoimmunotherapy was 85.2%. At 3 months postradiation, the larynx preservation rate was 88.9%. With a median follow-up of 18.7 months, the 1-year overall survival rate, progression-free survival rate, and larynx preservation rate were 84.7%, 77.6%, and 88.7%, respectively. When excluding those with pretreatment tracheostomy, the 1-year larynx preservation rate was 95.5%. Exploratory analysis revealed that relapse correlated with enrichment of RNA signature of hypoxia and M2 macrophage-associated genes.

Conclusions: Induction toripalimab combined with chemotherapy provided encouraging activity, promising larynx preservation rate and acceptable toxicity in this cohort of extensively locally advanced laryngeal and hypopharyngeal cancer.