CHICAGO -- Among head and neck cancer patients, women are significantly less likely to be treated with chemotherapy and radiation than men, researchers reported here.
The study by Jed Katzel, MD, of Kaiser Permanente in Santa Clara, California, and colleagues mined data from an extensive cancer registry, and found:
- Intensive chemotherapy with radiation was offered to women 35% of the time compared with 46% of the time for men (P=0.006)
- Radiation was performed on 60% of the women diagnosed with head and neck cancer and 70% of the men (P=0.008)
- There was no difference between the sexes in the rate of surgery to excise the cancers
- Women had almost double the risk of dying from head and neck cancer compared with men (adjusted relative HR 1.92, 95% CI 1.07-3.43).
"We weren't looking for gender differences, so the results were really surprising," Katzel said at a press conference at the annual meeting of the American Society of Clinical Oncology (ASCO). "Besides undertreatment, there are a number of factors that could contribute to the differences in outcomes between women and men with head and neck cancer, and it's clear we need further investigation."
He and his colleagues enrolled 223 women and 661 men with various head and neck cancers diagnosed from 2000 to 2015, and applied a validated generalized computing events (GCE) mathematical model to take into consideration differences in age, gender, tumor site, and Charlson score. The team evaluated the health outcomes for patients with stages II-IVB head and neck cancer treated at Kaiser Permanente Northern California, and the odds of receiving intensive cancer treatment were estimated using logistic regression models and adjusted for various possible confounding factors including history of smoking and alcohol use.
The GCE model was used to compare the risk of dying from cancer with the risk of dying from other causes, and in this analysis, the researchers did not control for differences in tumor type with respect to HPV status. A total of 38% of the women had oropharyngeal cancer compared with 55% of the men. These tumors, often caused by human papilloma virus (HPV) infection, generally are associated with better outcomes, Katzel said.
"This is a really striking study," commented Joshua Jones, MD, of Penn Medicine in Philadelphia and an ASCO-designated expert, who was not involved with the study. "It is surprising that there is a disparity in the treatment women get compared with men, but there are also disparities in the rate of death from head and neck cancer in women compared with men. We don't know why these differences exist, but it really is important that we continue this research to figure out what these differences are and why they are happening."
Jones told Ƶ that the difference may be due to patient preferences for treatments as well as possible influences from medical professionals.
Katzel, who noted that the study was a retrospective analysis, told Ƶ that the researchers plan to conduct a chart-by-chart review of the patients included in the trial in an attempt to drill down the reasons for the disparities in treatments and outcomes: "We want to go through these records to really understand the part of the story in which preferences for treatment were determined. These treatments can be considered to be very aggressive, and we need to understand why patients elect to have them and why others decline them and what the factors are that go into those decisions."
Disclosures
Katzel reported having no relationships with industry; co-authors reported personal or institutional relationships with Bayer, Bristol-Myers Squibb, and Merck.
Jones reported having no relevant relationships with industry.
Primary Source
American Society of Clinical Oncology
Park A, et al "Are women with head and neck cancer undertreated?" ASCO 2018; Abstract LBA6002.