Survival Outcomes of Non-squamous Cell Carcinoma and Rare Squamous Cell Carcinoma Variants of the Larynx

The literature focuses primarily on laryngeal differentiated squamous cell carcinoma (SCC), and only a limited number of studies have evaluated the outcomes of rare variants of SCC (vSCC) and non-SCC malignancies (nSCC). To our knowledge, this is the first study to compare the survival outcomes of these two groups. We retrospectively reviewed the records of 816 patients who underwent laryngeal surgery from January 2010 to November 2022. Forty-nine (6.2%) were identified as having unusual larynx malignancies and categorized in the nSCC or vSCC groups. The patients’ clinicopathological features were then recorded. We compared the two groups’ overall survival (OS) and recurrence-free survival (RFS) outcomes. Thirty-three (4.2%) patients had vSCC, and 16 (2%) had nSCC. Forty-two (85.7%) were male, and the mean age was 58.57 years. The median follow-up time was 69 months. The 5-year OS rate was 71.4% in the nSCC group vs. 87.9% in the vSCC group (p = .055). Only surgical margin (HR: 4.68; 95% CI:1.13–19.37, p = .033) was an independent prognostic factor for OS in the multivariable analysis. The 5-year RFS rate was 50% for the nSCC group compared to 90.9% for the vSCC group (p < .001). In the multivariable analysis, surgical margin positivity (HR: 21.0, 95% CI 3.97–98.1, p < .001), and lymphovascular invasion (HR: 0.043, 95% CI 0.005–0.357, p = .004) were independent prognostic factors for RFS. Although OS did not show a statistical difference, nSCC malignancies of the larynx demonstrated worse OS and RFS outcomes than vSCC malignancies.