Breast cancer recurrence more likely in black women

By Martha Kerr

LOS ANGELES (Reuters Health) - Ten years after breast-conserving therapy, the breast cancer recurrence rates are higher among African American women than among Caucasian women, researchers reported here at the annual meeting of the American Society for Therapeutic Radiology and Oncology (ASTRO). However, the difference is not great, so breast-conserving therapy should remain an option for African American women.

Dr. Meena S. Moran of Yale University School of Medicine in New Haven, Connecticut, and colleagues studied 2,382 women with breast cancer treated between 1975 and 2003 with conservative surgery followed by whole breast radiation, with or without regional lymph node radiation and adjuvant chemotherapy. Of the total, 218 were African American women with equal access to healthcare.

Conservative surgery for breast cancer, also referred to as "lumpectomy," a treatment option for some early-stage cancers, involves removal of the cancerous tumor, along with a border of healthy tissue surrounding it to insure that all of the cancer is removed.

The average follow-up period was 7 years. Breast cancer relapse after 5 years occurred in 13 percent of black and 7 percent of white women, Moran reported. At 10 years, the relapse rates were 17 percent and 13 percent for blacks and whites, respectively.

Features of the disease also differed markedly between the races, Moran continued. The percentage of black women who were younger than 40 years at diagnosis was 19.7 percent compared with 12.2 percent for white women. More black women had tumor stage T2 than white women, at 29 percent and 15 percent, respectively. (Tumor stage refers to the size and extent of the primary tumor and is rated from (T0 to T4.)

Breast cancer spread to the lymph nodes was detected in 32 percent of black and 24 percent of white women.

"Triple negative" disease was present in 35 percent of African American and 22 percent of Caucasian women. In triple-negative breast cancers, the cancer cells lack the receptors for estrogen, progesterone, and human epidermal growth factor receptor 2 (HER2) and therefore cannot be controlled with drugs, such as tamoxifen, which target these receptors, limiting treatment options.

Estrogen receptor-negative disease was present in 54 percent of black and 36 percent of white women.

Nearly one third (32 percent) of black women were positive for the tumor marker p53, indicating more aggressive disease, compared with 13 percent of Caucasian women.

After 10 years, distant spread, or "metastases," had occurred in 17 percent of African American and 13 percent of Caucasian women. Lymph node recurrence was seen in 6 percent of black women and 2 percent of white women, Moran reported.

An objective of the study was to assess how appropriate breast-conserving surgery is in African American women, given the more aggressive nature of their disease than in Caucasian women, she commented during her presentation at ASTRO.

"Although African American women have statistically significantly higher recurrence rates in breast and lymph nodes...the magnitude of the difference -- 17 percent versus 13 percent -- is still relatively small, suggesting that breast-conserving treatment remains an excellent treatment option for African American women wishing to conserve their breasts," Moran concluded.