Primary radical ablative surgery and fibula free-flap reconstruction for T4 oral cavity squamous cell carcinoma with mandibular invasion: oncologic and functional results and their predictive factors

The aims of this study were to evaluate clinical outcomes and to determine their predictive factors in patients with oral cavity squamous cell carcinoma (OCSCC) invading the mandibular bone (T4) who underwent primary radical surgery and fibula free-flap reconstruction. Between 2001 and 2013, all patients who underwent primary surgery and mandibular fibula free-flap reconstruction for OCSCC were enrolled in this retrospective study. Predictive factors of oncologic and functional outcomes were assessed in univariate and multivariate analysis. 77 patients (55 men and 22 women, mean age 62 ± 10.6 years) were enrolled in this study. Free-flap failure and local and general complication rates were 9, 31, and 22 %, respectively. In multivariate analysis, ASA score ( p = 0.002), pathologic N-stage ( p = 0.01), and close surgical margins ( p = 0.03) were independent predictors of overall survival. Six months after therapy, oral diet, speech intelligibility, and mouth opening functions were normal or slightly impaired in, respectively, 79, 88, and 83 % of patients. 6.5 % of patients remaining dependent on enteral nutrition 6 months after therapy. With acceptable postoperative outcomes and satisfactory oncologic and functional results, segmental mandibulectomy with fibula free-flap reconstruction should be considered the gold standard primary treatment for patients with OCSCC invading mandible bone. Oncologic outcomes are dependent on three main factors: ASA score, pathologic N-stage, and surgical margin status.