A new study suggests that many elderly women with HER2-positive (HER2+) metastatic breast cancer (mBC) do not receive guideline-concordant treatment. The study’s results were published in the Journal of the National Comprehensive Cancer Network.
Data from the Surveillance, Epidemiology, and End Results (SEER)-Medicare Linked Database were used in this retrospective, observational analysis of 241 women aged 66 years or older with HER2+ mBC. The researchers defined guideline-concordant treatment as being in line with the National Comprehensive Cancer Network (NCCN) Clinical Practice Guidelines in Oncology for Breast Cancer.
The researchers found that guideline-concordant treatment was being given to most of the women (76.8%) in this study cohort, but this suggested that almost one-quarter of these patients were not being treated according to guidelines. Receipt of guideline-concordant treatment was 5% less likely with every additional year of age at diagnosis (P =.0356).
A tendency to have more medical oncology visits was associated with receiving guideline-concordant treatment (P <.0001), as was the presence of good performance status (P =.0009). Positive hormone receptor (HR) status was also associated with receiving guideline-concordant treatment (P =.0298).
The researchers performed a decomposition analysis to determine reasons for the disparity in treatment by HR status. They found that numerous patient factors, including marital status, income, healthcare use, external healthcare environmental factors, and others, appeared to contribute to treatment disparities in women when stratified by HR status. However, most (81%) of the difference in rates of guideline-concordant treatment by HR status was not explained by identifiable factors.
“Almost one-quarter of the study cohort did not receive guideline-concordant treatment. Our data from decomposition analysis suggest opportunities to address cancer care for elderly women with negative HR status,” concluded the researchers in their report.
Vyas AM, Aroke H, Kogut S. Guideline-concordant treatment among elderly women with HER2-positive metastatic breast cancer in the United States. J Natl Compr Canc Netw. 2020;18(4):405-413.