Clinical outcome and comparison between squamous and non-squamous cell carcinoma of the larynx

Background: The various pathological types of non-squamous cell carcinomas (nSCCs) of the larynx accounted for about 5% laryngeal malignancies, but the knowledge regarding these pathological behaviors, therapeutic models and prognostic factors was limited. Objectives: To investigate the clinical characteristics and the survival outcomes of nSCCs of the larynx. Material and methods: A total of 106 patients diagnosed with laryngeal nSCC between 2003 and 2014 were retrospectively investigated from a cohort of 4,796 patients with laryngeal malignancies. Results: Spindle cell carcinoma, malignant salivary gland carcinoma, neuroendocrine carcinoma, non-Hodgkin’s lymphomas, and carcinosarcoma accounted for the majority of the nSCCs of the larynx. In laryngeal nSCCs (excluding non-Hodgkin lymphomas), there was no significant difference in overall survival (OS) by tumor subsite (p = .818), clinical-stage (p = .051) or T stage (p = .412), but the difference in OS by N stage was statistically significant (p = .001). Upon comparison of propensity score-matched groups, the OS was longer in SCCs of the larynx (p = .0004). Conclusions and significance: Primary nSCC of the larynx is rare, and its diagnosis depends on comprehensive immunohistochemical examination, as the clinical characteristics are non-specific compared with SCC. The overall prognosis of nSCC is relatively poor compared with that of SCC in the larynx.