Non-conventional laryngeal malignancies: a multicentre review of management and outcomes

Non-conventional laryngeal malignancies (NSCC) often have limited published data to guide management despite individual histopathological subtypes often exhibiting heterogeneous behaviour, characteristics, and treatment responses compared to laryngeal squamous cell carcinoma (SCC). This study aimed to compare oncological outcomes with SCC, specifically disease-free survival (DFS), disease-specific survival (DSS) and overall survival (OS). Secondary objectives were to compare treatment differences and perform a state of the art review.

This was a multicentre retrospective cohort study at four tertiary head and neck centres. Survival outcomes between NSCC and SCC patients were analysed with Kaplan-Meier curves and compared by log rank testing. Univariate Cox regression analysis was performed to predict survival by histopathological subgroup, T-stage, N-stage and M-stage.

There were no significant differences in 3-year DFS (p = 0.499), DSS (p = 0.329), OS (p = 0.360) or Kaplan Meier survival curves (DSS/OS) between SCC and overall NSCC groups. However, univariate Cox regression analysis identified "rare" histopathologies (mostly small cell carcinoma) to be predictive of less favourable OS (p = 0.035) but this result was not observed for other NSCC histopathological subgroups. N-stage (p = 0.027) and M-stage (p = 0.048) also predicted OS for NSCC malignancies. Significant differences in treatment modalities were identified with treatment of NSCC typically involving surgical resection and SCC often managed non-surgically (e.g., primary radiotherapy).

Although overall NSCC is managed differently compared to SCC, there do not appear to be differences in survival outcomes between these groups. N-stage and M-stage appear to be more predictive of OS than histopathology than many NSCC subtypes.