Have We Made Progress in Early Stage Vocal Cord Cancer with Impaired Cord Mobility?

Abstract

<h3>Purpose/Objective(s)</h3> The probability of cure after hypofractionated larynx radiotherapy (RT) decreases among patients with T2 glottic cancers with impaired cord mobility. The role of concurrent chemotherapy in this setting is unclear. We report outcomes of patients with T2 (and T3 based on paraglottic space invasion alone) N0 glottic squamous cell carcinoma (SCC) treated with curative-intent hypofractionated larynx RT with or without chemotherapy. <h3>Materials/Methods</h3> We retrospectively reviewed the medical records of all patients with AJCC 8^th edition stage T2-T3 N0 M0 SCC of the glottic larynx treated with curative intent at a single institution between 2000 and 2020. T3 patients were included if they were upstaged by paraglottic space invasion alone. All patients received hypofractionated RT (2.25 Gy/fraction) to the larynx to 63 - 65.25 Gy, with or without concurrent systemic therapy, and had at least 6 months of follow-up. Disease control and survival outcomes were calculated by the Kaplan-Meier method, and we used descriptive analysis to compare prognostic factors since more robust statistics were limited by sample size. <h3>Results</h3> The study population included 71 patients with a median follow-up time of 3.8 (range, 0.1 – 17.2) years. Major 2-year outcomes (95% CI) were as follows: local control, 74% (62% - 83%); regional control, 92% (83% - 97%); laryngectomy-free survival, 70% (58% - 80%); and overall survival, 82% (71% - 90%). Among the 23 patients who received systemic therapy (92% received weekly cisplatin or carboplatin), a greater proportion had impaired mobility (70% vs. 40%, p=0.02), larger median gross tumor volume (3.0 vs 1.6 cc, p=0.003), and subglottic extension (61% vs. 25%, p=0.008). Despite their worse prognostic factors, patients with impaired cord mobility who received chemotherapy experienced better local control and avoided total laryngectomy, without increased toxicity (see Table). One patient (4%) treated with chemotherapy required gastrostomy tube and tracheostomy during RT (both removed within 1 year). All but 6 late grade 3+ adverse events occurred after salvage laryngectomy for local recurrence. There were only 2 isolated regional relapses despite limited use of elective nodal RT (n=2). <h3>Conclusion</h3> The addition of concurrent platinum-based chemotherapy to hypofractionated larynx RT among patients with early-stage glottic SCC with impaired cord mobility appears safe, effective, and worthy of additional investigation.