Laryngeal spindle cell carcinoma: A population-based analysis of incidence and survival

OBJECTIVES/HYPOTHESIS: Laryngeal spindle cell carcinoma (LSpCC) is a rare variant of squamous cell carcinoma. Surgery is the reported mainstay of treatment, but previous analyses failed to demonstrate survival outcomes by therapeutic modality. This study aims to carry out the largest population-based analysis of this histology to determine tumor characteristics, incidence, survival, and prognostic indicators. METHODS: The National Cancer Institute's Surveillance, Epidemiology, and End Results database was queried for cases of LSpCC diagnosed between 1973 and 2011. Data was analyzed for patient demographics, incidence, treatment, and survival. RESULTS: A total of 312 cases of LSpCC were identified. Males comprised 87.2% of the cases, representing a male-to-female ratio of nearly 7:1. Whites accounted for 83.7% of LSpCC cases, whereas blacks represented 13.1%. Most cases (72.1%) arose in the glottis. The incidence of LSpCC from 2000 to 2011 was 0.023 per 100,000, with an annual percent change of -0.115%. One-, 5-, and 10-year disease-specific survival (DSS) rates for LSpCC were 90.9%, 74.1%, and 57.9%; whereas 1-, 5-, and 10-year relative survival rates were 91.0%, 77.7%, and 64.5%, respectively. Tumors of the glottis had a 5-year DSS of 84.0% compared to 51.9% for nonglottic tumors (P < 0.0001). High-stage (III/IV) LpSCC had lower 5-year DSS than low-stage (I/II) (36.8% and 91.8%, respectively) (P < 0.0001). Surgery imparted favorable 5-year survival, whereas radiotherapy did not impact survival rates. CONCLUSIONS: Laryngeal spindle cell carcinoma most commonly affects males and has a strong predilection for the glottis. Survival is best for glottic LSpCC. Surgery imparts a favorable prognosis compared to radiotherapy. LEVEL OF EVIDENCE: 4.