Gender disparities in head and neck cancer chemotherapy clinical trials participation and treatment

•Women are underrepresented in NCCN guideline-cited HNSCC chemotherapy trials.•Women are less likely to receive indicated chemotherapy in the definitive setting.•Reasons and ways to correct disparities should be studied further. To characterize the representation of women in clinical trials directing the National Comprehensive Cancer Network (NCCN) guidelines for chemotherapy use in head and neck squamous cell carcinoma (HNSCC), as well as the relationship between gender and chemotherapy administration in the definitive treatment of HNSCC in the United States. A review of all HNSCC chemotherapy clinical trials cited by the 2018 NCCN guidelines was performed. Sex-based proportions were compared with the corresponding proportions in the general U.S. population of patients with HNSCC between 1985 and 2015, derived from the Surveillance, Epidemiology, and End Results (SEER) program. A second analysis using the National Cancer Database (NCDB), identified 63,544 adult patients diagnosed with stages III-IVB HNSCC between 2004 and 2014 and treated with definitive radiotherapy or chemoradiotherapy. Univariable and multivariable logistic regression analyses were used to identify predictors of chemotherapy administration. While women comprised 26.2% of U.S. patients with HNSCC between 1985 and 2015, they comprised only 17.0% of patients analyzed in U.S. NCCN-cited chemotherapy clinical trials between 1985 and 2017. On multivariable analysis, women had decreased odds of receiving chemotherapy (Odds Ratio [OR]: 0.875; 95% Confidence Interval [CI]: 0.821–0.931; p