Tislelizumab combined with chemotherapy as neoadjuvant therapy for surgically resectable esophageal cancer: A prospective, single-arm, phase II study (TD-NICE)

BACKGROUND: Clinical benefit of neoadjuvant immunotherapy in resectable esophageal squamous cell carcinoma (ESCC). remains unclear. This study evaluated the efficacy and safety of the programmed death 1 (PD-1) inhibitor tislelizumab combined with chemotherapy as neoadjuvant therapy in patients with resectable ESCC. METHODS: Treatment-naïve patients were enrolled and eligible patients received 3 cycles of neoadjuvant therapy with tislelizumab, carboplatin, and nab-paclitaxel. The primary endpoint was surgery patients major pathological response (MPR). Subgroup analysis was stratified by tumor downstaging, circumferential resection margin (CRM), PD-ligand 1 (PD-L1) expression, and tumor mutation burden (TMB). Safety was assessed by adverse events (AEs) and postoperative complications. RESULTS: Between September 2020 and March 2021, 45 patients were enrolled. Thirty-six (80.0%) of 45 patients underwent surgery, and 29 (80.5%) underwent successful R0 resection. MPR and pathological complete response (pCR) for surgery patients were 72.0% and 50.0%, respectively. Intention to treatment (ITT) patients MPR and PCR were 57.5% and 40%. Downgrading occurred in 75% of 36 patients. MPR and pCR were identified to be associated with tumor downstaging and CRM but not PD-L1 expression or TMB. TPS levels in MPR and pCR group were significantly higher than that in Non-MPR and Non-pCR group, respectively. Treatment-related AEs of grade 3-4 and immune-related AEs occurred in 42.2% and 22.2% of 45 patients, respectively, and postoperative complications occurred in 77.8% of 36 patients. No treatment-related surgical delay or death occurred. No associations between gene mutation and pathological efficacy were observed. CONCLUSIONS: Tislelizumab plus chemotherapy as neoadjuvant therapy demonstrates promising antitumor activity for resectable ESCC with high rates of MPR, pCR, and R0 resection, as well as acceptable tolerability.