Margin burden and postoperative management after transoral laser microsurgery for laryngeal glottic squamous cell carcinoma: a multicentre retrospective study on 1216 patients

Objective. To evaluate the prognostic impact of surgical margin burden and postoperative management after transoral laser microsurgery (TOLMS) for glottic laryngeal squamous cell carcinoma (LSCC) in a large multicentre cohort. Methods. A retrospective multicentre study included 1216 patients with pT1-pT3 LSCC treated with TOLMS. Surgical margins were classified as free, single superficial positive, multiple superficial positive, or deep positive. Disease-free survival (DFS), disease-specific survival (DSS), and overall survival (OS) were analysed using Kaplan-Meier estimates and multivariable Cox models, accounting for pathological stage and postoperative management. Results. Pathological T category was independently associated with DFS and DSS. A single superficial positive margin showed DFS comparable to free margins. Multiple superficial positive margins were associated with increased recurrence risk, while deep margin involvement was strongly associated with both recurrence (hazard ratio [HR] 3.96) and disease-specific mortality (HR 6.82). Among patients with positive margins, second-look surgery achieved better DFS than postoperative radiotherapy or surveillance. Residual carcinoma at revision surgery was a major predictor of poor DFS and DSS. Conclusions. After TOLMS, oncologic risk is driven by margin type and burden rather than margin positivity alone. Deep margin involvement and residual disease identify patients requiring intensified management, supporting a risk-adapted postoperative strategy.