Immune Factors Tied to Aggressive Breast Cancers in Black Patients.

Abstract

Listen

Translate article

The research, led by a team from Roswell Park Comprehensive Cancer Center in Buffalo, New York, shows that an elevated number of “exhausted,” nonfunctional T cells seem to be causing tumors in patients of African descent to be more aggressive and harder to treat. The findings, the authors say, could lead to new treatments that would help to reduce the significant disparities in survival rates between Black and White patients with breast cancer. US breast cancer death rates among Black women are 40% higher than those among White women. In seeking answers to these disparities, researchers characterized infiltrating immune cells in the tumor microenvironments of 1315 patients with breast cancer from the Women's Circle of Health Study, a multi-institutional study that aims to evaluate factors explaining the earlier age at diagnosis and the more aggressive nature of breast cancer among Black women versus White women. Roswell Park researchers used both pathological and gene expression profiling to analyze the tumors. The findings indicated differences in the tumor immune responses when Black and White patients were compared. Although greater numbers of immune cells were present in Black patients, they also appeared to have less antitumor activity. Specifically, the tumor microenvironment in Black patients with breast cancer had a signature of exhausted versus total CD8+ T cells, which is associated with poor breast cancer survival, particularly in hormone receptor–positive breast cancer, according to the study's first author Song Yao, PhD, a Roswell Park professor of oncology. As a result, researchers noted that Black patients may have a higher response rate to immune checkpoint inhibitors. This population also experiences a stronger B-cell response, which has been shown to regulate responses to immunotherapy. The team also pointed to a lack of clinical trials for immune checkpoint inhibitors that have reported race-specific outcome data and called for enhanced recruitment of racial/ethnic minorities to improve cancer disparities in this area.