Free flap surgery for oral squamous cell carcinoma: Postoperative complications and its association with oncologic outcomes.

Abstract

e18096 Background: Surgical resection with free flap reconstruction is a cornerstone in the management of oral cavity squamous cell carcinoma (OCSCC). This study evaluates the impact of postoperative complications on overall survival (OS) and disease-specific survival (DSS) in this patient population. Methods: We conducted a retrospective cohort study of 87 OCSCC patients who underwent free flap reconstruction at our institution between 2010 and 2020. Postoperative complications were classified using the Modified Free-Flap Clavien-Dindo Classification (CD). Univariate and multivariate analyses were used to identify factors associated with OS and DSS. Results: Postoperative complications occurred in 66% of patients. Factors associated with complications included worse functional status (ECOG 1, 2), higher ASA scores, and pT4 tumors (Table). Reintervention for free-flap anastomosis complications did not affect survival. In multivariate analysis, CD-IVB complications (HR 13.1, 95% CI 1.99-86.11), positive margins (HR 2.17, 95% CI 0.99-4.76), and extracapsular invasion (HR 2.57, 95% CI 0.98-6.75) were associated with worse OS. Positive margins (HR 2.74, 95% CI 1.02-7.34) and extracapsular invasion (HR 5.48, 95% CI 1.27-23.7) correlated with worse DSS. Conclusions: Severe postoperative complications (CD-IVB), positive surgical margins, and extracapsular invasion are independent predictors of worse OS in OCSCC patients undergoing free flap reconstruction. Positive margins and extracapsular invasion are also associated with worse DSS. Association of clinical and pathological variables with perioperative complications. Variable No complications With complications p-value Duration of surgery (minutes) 660 ± 191 590 ± 91 0.60 ICU stay (days) 7+ ± 3.5 8 ± 7 0.14 Hospital stay (days) 20 ± 12 21 ± 28 0.79 Age 0.11  <=64 years 15 (71.4) 32 (48.5)  >=65 years 6 (28.6) 34 (51.5) Sex 0.84  Male 9 (42.9) 32 (48.5)  Female 12 (57.1) 34 (51.5) ECOG 0.02  0 12 (57.1) 32 (48.5)  1 7 (33.3) 34 (51.5)  2 2 (9.5) 0 (0) ASA Score 0.01  I 3 (14.3) 1 (1.5)  II 10 (47.6) 23 (34.8)  III 8 (38.1) 42 (63.6) Number of subsites 0.74  1 13 (61.9) 41 (62.1)  2 6 (28.6) 18 (27.3)  3 2 (9.5) 4 (6.1)  4 0 (0) 3 (4.5) pT stage 0.01  T2 2 (10) 3 (4.6)  T3 11 (55) 13 (20)  T4a 6 (30) 46 (70.8)  T4b 1 (5) 3 (4.6) pN stage 0.65  N0 11 (55) 24 (37.5)  N1 1 (5) 8 (12.5)  N2b 3 (15) 7 (10.9)  N2c 0 (0) 1 (1.6)  N3b 5 (25) 24 (37.5) M stage 1  M0 21 (100) 65 (98.5)  Mx 0 1 (1.5) Charlson Comorbidity Index 0.02  0 8 (36.4) 8 (12.5)  1 4 (18.2) 9 (14.1)  2 4 (18.2) 23 (35.9)  3 4 (18.2) 15 (23.4)  4 2 (9.1) 9 (14.1) Positive margins 0.29  Yes 13 (61.9) 32 (48.5)  No 8 (38.1) 34 (51.5) Perineural invasion 0.53  Yes 12 (57.1) 34 (51.5)  No 9 (42.9) 32 (48.5) Extracapsular extension 0.33  Yes 5 (23.8) 24 (36.4)  No 16 (76.2) 42 (63.6)