Impact of Adjuvant Radiotherapy in Squamous Cell Carcinoma of the Oral Cavity with Perineural Invasion

ObjectiveCurrent guidelines indicate postoperative radiotherapy (PORT) in oral squamous cell carcinoma (OSCC) with perineural invasion (PNI), however, its real benefit has never been proven. The aim of our study is to investigate the benefit of PORT in OSCC patients with PNI in terms of survival and disease control.Data SourcesThe Pubmed/MEDLINE, Cochrane Library, and Scopus databases.Review MethodsPatients with PNI + OSCC treated with primary surgery were extracted from the included studies. The pooled logHR was calculated by comparing patients who underwent PORT to those who underwent only observation for overall survival (OS), disease-specific survival (DSS), disease-free survival (DFS), and locoregional control (LRC).ResultsAbout 690 patients with primary OSCC and PNI were included from nine studies. 374 (54.2%) patients underwent PORT, while 316 (45.8%) underwent observation. Analyses showed non-significant difference between the two groups for OS (HR: 1.01; 95% CI: 0.38-2.69), DSS (HR: 2.03; 95% CI: 0.54-7.56), and LRC (HR: 0.89; 95% CI: 0.53-1.50). They showed a significant difference in terms of DFS (HR: 0.86; 95% CI: 0.77-0.97).ConclusionThe real benefit of PORT in OSCC patients with PNI is still unclear, although it may have a positive impact on DFS. Clinicians should consider individual patient's characteristics, tumor factors, and treatment goals when deciding whether to recommend PORT. Further studies are needed to clarify which entity of PNI really benefits from PORT.Level of EvidenceN/A Laryngoscope, 2023 Our study showed that adjuvant radiotherapy may improve the outcomes of patients affected by oral cavity cancer with perineural invasion by reducing the risk of disease recurrence or progression. Other patient and tumor characteristics, other than treatment objectives, should be considered in the decision-making.image