The Role of Adjuvant Therapies in Improving Outcomes for pT1-3N0 Oral Squamous Cell Carcinoma With Tumour-Free Margins and Perineural Invasion

Introduction The role of concomitant chemoradiation therapy (CTRT) or radiation therapy (RT) is not well defined in operated cases of oral squamous cell carcinoma (OSCC) with positive perineural spread. The purpose of the study was to determine whether the use of concurrent CTRT or RT would enhance the five-year disease-free survival of patients with positive perineural invasion (PNI). Materials and methods Data were analysed retrospectively from January 2014 to December 2023. Patients were placed into three groups: surgery only, surgery with RT, and surgery with concomitant CTRT. In all, 180 cases of pT1-3N0 and pT1-3N+ OSCC patients had tumour-free margins, of which 24 cases (13.4%) had perineural invasion. Based on treatment modalities, 45.8% of the cases underwent surgery with CTRT (group III), 33.3% opted for surgery with RT (group II), and 20.9% underwent surgery only (group I). Five-year recurrence-free survival was analysed among the three groups using the Kaplan-Meier model. Results There was no significant difference among the three groups in terms of recurrence (p = 0.817) or five-year survival rate (p = 0.0935). Conclusion Altogether, the data seem to indicate that radical surgical resection alone should be considered sufficient treatment for OSCC patients with pT1-3N0 disease, even in the presence of perineural invasion. Thus, it can be concluded that the addition of concomitant CTRT or RT does not significantly increase the five-year disease-free survival of patients with OSCC with positive PNI.