Predictors of chemotherapy and its effects in early stage squamous cell carcinoma of the larynx

BACKGROUND: Squamous cell carcinoma (SCC) of larynx is a common head and neck cancer. For cases that are node negative, the role of definitive concurrent chemoradiation is unclear and not supported by guidelines but used at provider discretion. To address this knowledge gap, we examined the oncological outcomes with additional chemotherapy and factors correlated with the chemotherapy administration. METHODS: We queried the National Cancer Database for patients with early stage (T2N0M0) laryngeal SCC treated nonsurgically. Multivariable logistic regression identified predictors of chemotherapy. Multivariable Cox regression evaluated predictors of survival. Propensity matching accounted for indication biases. RESULTS: We identified 7181 patients meeting the eligibility criteria, of which 1568 (22%) patients received chemotherapy in addition to radiation. Predictors of chemotherapy use included younger age, Caucasian race, more remote year of treatment, higher grade, sites other than glottis, treatment at a community cancer center, and use of intensity‐modulated radiation therapy. Median overall survival was not significantly different in the two arms analyzed—65 months (95% confidence interval [CI] 60, 72months) with chemotherapy compared to 70 months without chemotherapy (95% CI 66, 75 months, P<.37). Predictors for survival on propensity‐matched multivariable analysis were increased age, male sex, less education, lower income, higher comorbidity score, receipt of treatment at a community center, and nonglottic sites. CONCLUSIONS: This study shows no clear survival benefit with chemotherapy in early stage disease. Although this implies that chemotherapy should not be routinely delivered, individualized judgment and prospective studies are recommended as the biology behind this interesting finding is undefined. LEVEL OF EVIDENCE: 2C (Outcomes Research).