New Haven, Conn.—African American women are diagnosed with breast cancer at a younger age and have larger tumors and more lymph node involvement than Caucasian women, a Yale School of Medicine researcher reported today.
Speaking at the American Society for Therapeutic Radiology and Oncology meeting in Los Angeles, Meena Moran, M.D., assistant professor of therapeutic radiology and Yale Cancer Center member, said her results were based on 2,164 Caucasian women and 207 African American women followed over a 30-year period—the largest most comprehensive study of its kind to date. All underwent lumpectomies in which the tumor, not the entire breast, was removed.
The incidence of breast cancer is actually lower in African American women compared to Caucasian women, yet their mortality rates are higher, Moran said. We were surprised. Previous reports did not show higher relapse rates in African American women after surgery to conserve breast tissue. This might be because we had so many African American patients and a longer follow-up period.
She said there are several possible biological risk factors that need to be explored more fully. African American women have a lower level of estrogen/progesterone receptors, which means existing anti-estrogen therapies are not effective on these tumors. African American women have a higher rate of triple negative tumors, which have been associated with a worse outcome in early stage breast cancer. They also have a higher rate of mutation in the p53 gene, which normally acts to suppress tumors.
In terms of outcomes after treatment, Moran said, African American patients were found to have a significantly higher rate of relapse in the breast and lymph nodes after breast conservation treatment compared to Caucasians. We did not, however, find any differences in the rate of cancer spreading to other locations such as the lung, bone, or liver, or in the overall survival in the two groups of patients.
Moran said she hoped that the study would increase awareness of the aggressive nature of breast cancer in African American women. She said this does not mean that African American women should not have lumpectomies. She emphasized that greater attention should be paid to ensure the tumor is completely removed and that follow up radiation therapy is adequate and includes the entire breast and lymph nodes.
We hope that patients and physicians will help reduce the gap in the disparities between the two populations by improving early detection/screening, better access to care and compliance with chemotherapy and radiation, Moran said. These patients can modify their lifestyles to decrease risk factors, such as obesity. There also is a need for African American patients to take part in large breast cancer studies to better understand the ethnicity based differences in breast cancer.