Barrier-to-depth ratio as a potential predictor of cervical lymph node metastasis and prognosis in oral tongue squamous cell carcinoma.

Anatomical barriers, such as the sublingual and paralingual spaces, may affect tumor spread, but reliable imaging-based predictors of cervical lymph node metastasis (LNM) in oral tongue squamous cell carcinoma (OTSCC) are limited. This study aimed to evaluate the association of the magnetic resonance imaging (MRI)-derived barrier-to-depth ratio (BDR) with cervical LNM and survival in OTSCC, and to integrate BDR into a prognostic nomogram. A retrospective cohort study was performed at Beijing Stomatological Hospital, Capital Medical University, including patients with OTSCC who underwent preoperative MRI and primary surgical resection. The BDR was measured and its predictive value for cervical LNM was analyzed using logistic regression. Survival outcomes were assessed using Cox proportional hazards models. A nomogram combining BDR and other clinicopathological factors was constructed. Of 125 subjects, 58 (46.4%) had cervical LNM. The mean BDR was significantly lower in patients with cervical LNM than in those without (p < 0.001). Patients with a BDR ≤0.22 had significantly poorer OS and DSS than those with BDR >0.22 (p < 0.001). The nomogram incorporating BDR achieved a C-index of 0.748, compared with 0.683 for TNM staging alone. MRI-derived BDR appears to be a novel and clinically relevant prognostic parameter in OTSCC. Incorporation of BDR into risk stratification models may improve individualized prognostic assessment and support clinical decision making regarding elective neck dissection.