Clinical Outcomes of Taiwanese Patients with Resected Oral Cavity Squamous Cell Carcinoma Who Underwent Reconstruction with Free Versus Local Flaps

Background: We sought to compare the clinical outcomes of Taiwanese patients with resected oral cavity squamous cell carcinoma (OCSCC) who underwent reconstruction with free versus local flaps. Methods: From 2011 to 2017, we examined 8646 patients with first primary OCSCC who received surgery either with or without adjuvant therapy. Of these patients, 7297 and 1349 received free and local flap reconstruction, respectively. Two propensity score-matched groups of patients who underwent free versus local flap (n = 1268 each) reconstructions were examined. Margin status was not included as a propensity score-matched variable. Results: Compared with local flaps, patients who received free flaps had a higher prevalence of the following variables: male sex, age < 65 years, pT3−4, pN1−3, p-Stage III−IV, depth ≥ 10 mm, margin > 4 mm, extranodal extension (ENE), and adjuvant therapy (all p < 0.0001). Multivariable analysis identified the reconstruction method (local vs. free flaps, only overall survival [OS]), age ≥ 65 years, pT3−4, pN1−3, p-Stage III−IV, depth ≥ 10 mm (only OS), margins ≤ 4 mm, and ENE as independent adverse prognosticators for disease-specific survival (DSS) and OS. The results of propensity score-matched analyses revealed that, compared with free flaps, patients who underwent local flap reconstruction showed less favorable 5-year DSS (hazard ratio [HR] 1.26, 82%/77%; p = 0.0100) and OS (HR 1.21, 73%/68%; p = 0.0079). Conclusions: After adjusting for covariates using multivariate models, and also by propensity score modeling, OCSCC patients who underwent free flap reconstruction showed a higher frequency of clear margins and a significant survival advantage compared with those who received local flaps.