The efficacy and safety of adding PD-1 blockade to induction chemotherapy and concurrent chemoradiotherapy (IC-CCRT) for locoregionally advanced nasopharyngeal carcinoma: an observational, propensity score-matched analysis.

BACKGROUND: Despite the success of PD-1 blockade in recurrent/metastatic nasopharyngeal carcinoma (NPC), its effect for locoregionally advanced NPC (LANPC) remains unclear. This study aimed to evaluate the benefit of adding PD-1 blockade to the current standard treatment (gemcitabine and cisplatin IC  plus cisplatin CCRT ) for LANPC patients. METHODS: From January 2020 to November 2022, 347 patients with non-metastatic high-risk LANPC (stage III-IVA, excluding T3-4N0) were included. Of the 347 patients, 268 patients were treated with standard treatment (IC-CCRT), and 79 received PD-1 blockade plus IC-CCRT (PD-1 group). For the PD-1 group, PD-1 blockade was given intravenously once every 3 weeks for up to 9 cycles (3 induction and 6 adjuvant). The primary endpoint was disease-free survival (DFS) (i.e. freedom from local/regional/distant failure or death). The propensity score matching (PSM) with the ratio of 1:2 was performed to control confounding factors. RESULTS: After PSM analysis, 150 patients receiving standard treatment and 75 patients receiving additional PD-1 blockade remained in the current analysis. After three cycles of IC, the PD-1 group had significantly higher rates of complete response (defined as disappearance of all target lesions; 24% vs. 9%; P = 0.006) and complete biological response (defined as undetectable cell-free Epstein-Barr virus DNA, cfEBV DNA; 79% vs. 65%; P = 0.046) than that in the standard group. And the incidence of grade 3-4 toxicity during IC was 47% in the PD-1 group and 41% in the standard group, with no significant difference (P = 0.396). During follow-up period, additional PD-1 blockade to standard treatment improved 3-year DFS from 84 to 95%, with marginal statistical significance (HR, 0.28; 95%CI, 0.06-1.19; P = 0.064). CONCLUSION: Additiaonl PD-1 blockade to gemcitabine and cisplatin IC and adjuvant treatment results in significant improvement in tumor regression, cfEBV DNA clearance, superior DFS, and comparable toxicity profiles in high-risk LANPC patients.

Neoadjuvant chemotherapy plus concurrent chemoradiotherapy versus concurrent chemoradiotherapy alone in elderly patients with stage III-IVa nasopharyngeal carcinoma: A real-world study based on medical comorbidities.

PURPOSE: To evaluate the outcomes and toxicities of adding neoadjuvant chemotherapy (NAC) to concurrent chemoradiotherapy (CCRT) in elderly (≥65 years) patients with locoregionally advanced nasopharyngeal carcinoma (LANPC, stage III-IVa). METHODS AND MATERIALS: Using an NPC-specific database, 245 elderly patients with stage III-IVa NPC, receiving CCRT +/- NAC, and an Adult Co-morbidity Evaluation 27 (ACE-27) score <2 were included. Recursive partitioning analysis (RPA) based on TNM stage and Epstein-Barr virus (EBV) DNA were applied for risk stratification. The primary end point was disease-free survival (DFS). RESULTS: Two risk groups were generated by the RPA model. In the high-risk group (EBV DNA < 4000 copy/ml with stage IVa & EBV DNA ≥4000 copy/ml with stage III-IVa), patients treated with NAC plus CCRT achieved improved 5-year DFS rates compared to those who received CCRT alone (56.9% vs. 29.4%; p = 0.003). But we failed to observe the survival benefit of additional NAC in the low-risk group (EBV DNA <4000 copy/ml with stage III). The most common severe acute toxic effects were leucopenia (46.8% vs. 24.4%) and neutropenia (43.7% vs. 20.2%) in the NAC plus CCRT group versus CCRT group with statistically significant differences. CONCLUSIONS: The addition of NAC to CCRT was associated with better DFS for the high-risk group of elderly LANPC patients with ACE-27 score <2. However, the survival benefit of additional NAC was not observed in low-risk patients.