A Retrospective Study of Two Mandibulectomy Approaches for T3-Stage Lower Gingival Carcinoma.

OBJECTIVE

This study retrospectively analyzes two mandibular resection techniques for T3-stage lower gingival carcinoma, aiming to compare their impact on patient prognosis.

METHODS

Retrospective cohort study. Data from 78 cases of T3-stage lower gingival carcinoma involving the mandible were reviewed in our Department of Head and Neck Surgery. These cases included patients who underwent either marginal mandibulectomy or segmental mandibulectomy. A cohort analysis was performed to evaluate the clinical outcomes and identify factors influencing prognosis in T3-stage lower gingival carcinoma.

RESULTS

Thirty-eight patients underwent marginal mandibulectomy, while 40 underwent segmental mandibulectomy. The 3-year overall survival (OS) rate in the marginal mandibulectomy group was 70.8%, with a 5-year OS rate of 52.1%. In the segmental mandibulectomy group, the 3-year OS was 68.1%, and the 5-year OS rate was 52.7%, with no statistically significant difference between the two groups (p > 0.05). The 3-year disease-free survival (DFS) rate was 67.4% in the marginal mandibulectomy group and 50.7% at 5 years, compared to 62.2% and 57.4%, respectively, in the segmental resection group, again showing no statistically significant difference in DFS between the two groups (p > 0.05). However, patients in the marginal resection group demonstrated superior postoperative mandibular functional preservation. Multivariate Cox regression analysis identified advanced age, lymph node metastasis, poor pathological differentiation, and lack of adjuvant radiotherapy as independent risk factors for poor prognosis.

CONCLUSION

The marginal mandibulectomy has been proven to be an oncologically safe method with satisfactory mandibular functional outcomes in selected cases of T3-stage lower gingival carcinoma.