Black women with breast cancer are more likely to die of the disease than white women, a fact that has often been linked to less access to care. But emerging research, including a paper presented this week at the San Antonio Breast Cancer Symposium, suggests that a difference in tumor biology may also play a factor.
In the study, researchers compared the tumor biology of 96 Black women with breast cancer to that of 87 white women. Within these groups, 49 percent of the Black women had their cancer spread, versus 35 percent of white women. The tumors of Black women had higher tumor microenvironment of metastasis (TMEM) scores, a marker that can help predict the likelihood that a cancer will spread.
Even after adjusting for other factors such as age, type, and size of the tumor, having a high TMEM doorway score was linked to a more likely spread of cancer, according to Maja H. Oktay, MD, PhD, professor and co-leader of the Tumor Microenvironment and Metastasis Program at Montefiore Einstein Cancer Center in the Bronx, New York, and senior author of the study.
“Our study provides a potential explanation for the persistent racial disparities in some forms of breast cancer that is not fully explained by disparities in social determinants of health, such as access to care or treatment,” said Dr. Oktay.
The study also found that giving chemotherapy before surgery, a common practice to shrink tumors in an effort to make surgery less drastic, actually increased TMEM scores in this population of women.
“It produces changes surrounding the tumor that might increase the risk of the cancer spreading,” said Oktay, at the press conference. Oktay called the finding “a previously unrecognized mechanism of resistance to chemotherapy.” More research will be necessary before the findings prompt widespread changes in the way breast cancer is treated, said Oktay.
The study is eye opening, according to Camelia Lawrence, MD, director of breast surgery for the Hospital of Central Connecticut (HOCC) and Midstate Medical Center, who was not involved in the study. “There’s still so much unknown about breast cancer in Black women and so much work that still needs to be done,” she said.