SAN ANTONIO – Black women are significantly less likely to receive a sentinel lymph node biopsy than are white women – and significantly more likely to develop lymphedema, a large database study has determined.
Among more than 31,000 women with invasive breast cancer diagnosed from 2002-2007, 62% of black women underwent the procedure, compared with 74% of white women – a significant difference (P less than .001).
That disparity led to a doubling in the risk of lymphedema in black women, compared with white women, Dr. Dalliah Black said at the San Antonio Breast Cancer Symposium. Axillary sentinel lymph node biopsy (SLNB) is a less-invasive alternative to axillary lymph node dissection (ALND) for breast cancer staging.
The disparity appears to be regional, said Dr. Black of the University of Texas M.D. Anderson Cancer Center in Houston. A preliminary subanalysis of 12 regions in the database found that Louisiana had the lowest rate of sentinel node biopsy among blacks (58%), while Seattle had the highest (89%). Regional differences were related not only to the patient’s socioeconomic status but to the numbers of surgeons available in the region.
Dr. Black used data extracted from the U.S. national Surveillance, Epidemiology, and End Results (SEER) database. The patient group consisted of 31,274 women diagnosed between 2002 and 2007. All patients had invasive breast cancer with no evidence of distant metastasis and underwent a documented axillary surgical procedure. All of the patients had fee-for-service coverage.
Black women composed 6% of the group (1,767). The median age was 74 years; 75% of the patients had a tumor size of 2 cm or smaller. Most (62%) had undergone a lumpectomy, and 73%, a sentinel lymph node biopsy.
The median number of sentinel nodes removed was two, and the median number of axillary nodes, 11.
The rate of sentinel node biopsy increased in both groups over the study period, as the surgery moved from being an alternate management approach to the preferred approach. But the disparity persisted, Dr. Black said. By 2007, the biopsy rate was 70% among black women and 83% among white (P less than .001).
The difference in SLND was also associated with a significantly increased rate of lymphedema. By 5 years after surgery, lymphedema had developed in 18% of black women who had an axillary node biopsy compared with 7% of white women who had a sentinel node biopsy. But when black women had a sentinel node biopsy, their 5-year rate of lymphedema was similar to the rate among white women (9%; P less than .001).
"This shows that if black women had gotten the appropriate surgery, they were not at any increased risk for lymphedema," Dr. Black said.
She intends to reanalyze the groups when the 2010 SEER data is released next spring. "We hope to see the disparity reduced in that analysis, although it may not be," she said in an interview. "If it’s not, we really need to figure out how we can work with national programs to disseminate guidelines and provide reminders to surgeons and multispecialist breast cancer teams – as well as to patients, so they can advocate for themselves. But it’s not only the patient’s responsibility. It’s a two-way street. We need to take some responsibility for this problem."
Dr. Black has no relevant financial relationships to disclose.