Initial negative resection margin versus revised negative resection margin in patients who underwent surgery without adjuvant therapy for early-stage oral tongue squamous cell carcinoma

Background: In cases of positive resection margin (RM), re-resection is generally recommended. There has been controversy about the oncologic impact of revised negative RMs after re-resection. The aim of this study was to investigate the oncologic impact of revised negative RM in patients who underwent surgery without adjuvant therapy for early-stage (pT1-2/N0) oral tongue squamous cell carcinoma (OSCC).

Methods: We retrospectively analyzed patients with pT1-2 N0 OSCC who did not receive adjuvant therapy (N=441). These patients were classified into an initial negative RM (R0, n = 380) group and a revised negative RM (R1-R0, n = 61) group. Demographic and clinical data (T stage, tumor length, depth of invasion [DOI], lymphovascular invasion [LVI], perineural invasion [PNI], and recurrence) were compared between the R0 and R1-R0 groups.

Results: Age, sex, T stage, DOI, LVI, PNI, and SUVmax were not significantly different between the two groups. Local recurrence was more frequent (P=0.045) in the R1-R0 group (13.1 %) than in the R0 group (5.5 %). Local recurrence-free survival was better in the R0 group than in the R1-R0 group (P=0.046). There was no significant difference in overall recurrence or overall survival. On multivariate analysis, initial positive RM was the independent significant risk factor (hazard ratio, 2.249; 95 % confidence interval, 1.025-4.935; P=0.043) for local recurrence.

Conclusion: A revised clear RM after initial cut-through margin is a risk factor for local recurrence in early-stage OSCC. Cautious should be considered in early-stage OSCC patients with revised clear RM.