Intraoperative Bone Marrow Frozen Sections Reduce Positive Final Margins in Mandibulectomy

Objectives To assess the impact of intraoperative bone marrow frozen section (IBMFS) use on final margin status and survival outcomes in patients undergoing mandibulectomy for squamous cell carcinoma (SCC) and non‐SCC neoplasms. Methods A single‐center retrospective cohort study was performed of patients undergoing segmental or marginal mandibulectomy for benign or malignant neoplasms between 2009 and 2025. The medical record was reviewed for demographic data, histopathologic disease features, treatment, and outcomes. Univariable and multivariable Cox regression analyses were used to evaluate associations between IBMFS and recurrence‐free and overall survival among patients with SCC. Results Of 235 cases, IBMFS were performed in 80.4%. IBMFS analysis was associated with reduced rates of positive final bone margins (1.1% vs. 8.7%, p = 0.014) and overall positive margins (7.9% vs. 19.6%, p = 0.029). Positive IBMFS rate was higher among non‐SCC neoplasms than SCC (23.5% vs. 3.5%, p = 0.007), with no significant difference in rate of final positive margins. IBMFS results demonstrated 90.0% sensitivity, 99.4% specificity, and 98.9% concordance with final histopathology. Among SCC patients, IBMFS use was not significantly associated with recurrence‐free survival (aHR 0.671, p = 0.320) or overall survival (aHR 0.967, p = 0.923); only nodal disease and age were significantly associated with survival. Conclusions In this retrospective single‐center cohort, IBMFS use was associated with improved final margin control across tumor types, including non‐SCC neoplasms. Although no survival benefit was demonstrated, its association with margin clearance suggests that IBMFS may be a useful intraoperative adjunct in mandibulectomy for head and neck neoplasms.