omitting neck dissection in cT3-4N0M0 oral squamous cell carcinoma with Imaging-Negative nodes after neoadjuvant chemoimmunotherapy: A retrospective cohort study.

OBJECTIVE

To retrospectively analyze oncologic and prognostic outcomes among cT3-4N0M0 oral squamous cell carcinoma (OSCC) patients with post-neoadjuvant imaging-negative cervical lymph nodes, stratified by whether cervical lymph node dissection (CD) was performed after PD-1 inhibitor combined with TP neoadjuvant immunotherapy.

METHODS

This retrospective study included cT3-4N0M0 OSCC patients treated at Sun Yat‑sen University Cancer Center (Oct 2019-Jul 2023) with 3-4 cycles of neoadjuvant immunotherapy. All underwent extended primary tumor resection and postoperative concurrent chemoradiotherapy, and were divided into CD group (n = 30) and non-CD (NCD) group (n = 28) based on whether CD was performed.

PRIMARY ENDPOINT: cervical lymph node control rate. Secondary endpoints: disease‑free survival (DFS) and overall survival (OS). Kaplan‑Meier and Cox regression were used.

RESULTS

A total of 58 patients with cT3-4N0M0 OSCC who received PD-1 inhibitor + TP were included, median follow‑up was 38 months. The 36‑month cervical lymph node control rate was 93.21% (CD) vs 85.43% (NCD) (HR = 2.14, 95%CI 0.43-10.61, P > 0.05). 36‑month DFS: 82.11% vs 70.59% (HR = 1.26, 95%CI 0.42-3.76, P > 0.05). 36‑month OS: 86.67% vs 87.05% (HR = 0.61, 95%CI 0.15-2.48, P > 0.05). Subgroup analyses showed no significant survival benefit of CD across age, sex, ECOG PS, neoadjuvant response, or T stage.

CONCLUSION

In cT3-4N0M0 OSCC patients with post‑neoadjuvant imaging‑negative cervical nodes (short‑axis diameter < 10 mm, no suspicious nodes), omitting CD may not lead to a meaningful elevation in cervical recurrence risk or compromise DFS/OS.