OBJECTIVE: Accurate staging of advanced laryngeal cancer is important, as treatment can vary significantly between larynx preservation and total laryngectomy. The purpose of this study was to evaluate the accuracy of magnetic resonance imaging (MRI) in assessing features of T4a disease in locally advanced laryngeal cancer and determine if primary site played a role in the accuracy of MRI in this setting. METHODS: A retrospective cohort study of patients undergoing a total laryngectomy in a tertiary referral center for head and neck cancer over a 10-year time period was carried out. Patients met inclusion criteria if they underwent a primary total laryngectomy for squamous cell carcinoma (SCC) of the larynx during the study period. Data collected included basic demographic data, primary tumor subsite, and clinical and pathological staging. The predictive ability of MRI on outer thyroid cortex invasion, extralaryngeal extension, and overall T4a stage was analyzed with receiver operating characteristics analysis. Analysis was compared to histological data on outer thyroid cortex invasion, extralaryngeal extension, and histological T4a stage. RESULTS: A total of 112 patients met inclusion criteria. The mean age of the cohort was 65.1. Glottic primary subsite was associated with a statistically significant elevated risk for histological outer cortex erosion (p = 0.006), but MRI demonstrated worse sensitivity in detecting this outer cortex invasion in glottic primaries(p = 0.002). CONCLUSION: Glottic primaries tumors display an increased likelihood of thyroid cartilage invasion, however, MRI demonstrates a poorer sensitivity for detecting these features. LEVEL OF EVIDENCE: 3 Laryngoscope, 135:723-728, 2025.
