Adjuvant radiotherapy in pT3 glottic squamous cell carcinoma: an unnecessary burden?

The role of adjuvant radiotherapy (RT) in pT3 glottic squamous cell carcinoma (SCC) remains a topic of controversy. While guidelines recommend postoperative RT for patients with adverse features, its actual oncological benefit and functional impact are uncertain. We conducted a bicentric retrospective analysis with surgically treated pT3 glottic SCC. Survival outcomes were assessed with Kaplan–Meier and Cox regression models. Pathological risk factors of interest included positive/close margins, perineural invasion (PNI), lymphovascular invasion (LVI), subglottic extension, pN1 status, and posterior laryngeal involvement. Functional outcomes were assessed with EORTC QLQ-HN35, MDADI, and INFVo questionnaires, comparing irradiated and non-irradiated patients, with subgroup analyses by surgical approach. Adjuvant RT did not significantly improve overall survival (OS) or disease-free survival (DFS) in the entire cohort. PNI, LVI, and posterior involvement showed the most substantial adverse prognostic impact. Functional outcomes were comparable overall, but a slight deterioration was observed after open partial laryngectomy (OPL), whereas no differences emerged after total laryngectomy (TL) or transoral laser microsurgery (TLM). In this series, adjuvant RT did not improve oncological outcomes and had only a limited functional impact. These findings suggest that indications for postoperative RT in pT3 glottic SCC may need to be restricted to selected high-risk features and tailored to the surgical approach. Prospective studies with larger cohorts are needed to refine patient selection.