Necessity of applying anatomical unit resection surgery in suspected posterior oral squamous cell carcinoma

Anatomic unit resection surgery (AURS), previously introduced, significantly improves the prognosis of oral cell squamous carcinoma (OSCC) patients with posterior oral anatomical complex (POAC) involvement. This study aims to evaluate the necessity of AURS in patients with OSCC suspected to involve the POAC.

We conducted a retrospective study of 127 patients diagnosed OSCC with identical POAC involvement or suspected POAC involvement. Patients were classified based on the extent of POAC involvement determined from preoperative imaging. Kaplan-Meier analysis was performed to identify the impact of surgery approaches on the prognosis of patients. Univariable and multivariable cox analysis were conducted to identify independent prognostic factors of the patients.

In total, 65 patients with suspected POAC involvement, 24 cases underwent AURS while 41 underwent conventional surgery. 62 patients with identical POAC involvement, 31 cases underwent AURS while 31 underwent conventional surgery. The AURS group demonstrated significantly superior disease-free survival (DFS) rates (75.0% vs. 43.9%) and local-regional control rates (79.2% vs. 48.8%) for suspected POAC involvement. For identical POAC involvement, AURS also resulted in better DFS (51.6% vs. 19.4%) and local-regional control (64.5% vs. 25.8%). Surgery protocol, tumor involvement level, lymphatic invasion and pN staging were identified as independent prognostic factors for both DFS and local-regional control.

AURS is a necessary surgical approach for both suspected and identical POAC involvement in OSCC patients, significantly improving prognosis and local-regional control rate.