Racial variations found in breast cancer type and size

August 22, 2007

NEW YORK (Reuters Health) - Among women with a first breast cancer, black women are more likely to have larger tumors and to have more positive lymph nodes than white women, an analysis of the National Cancer Institute's Surveillance, Epidemiology, and End Results (SEER) database shows.

Dr. Alfred I. Neugut and colleagues at Columbia University Medical Center in New York identified 21,861 black and 256,174 white women first diagnosed with breast cancer between 1988 and 2003, with a primary tumor in stage I through IIIA.

More black women than while women had tumors measuring 2.0 cm or greater, and the adjusted odds ratio for having one or more positive lymph nodes was 1.24 for black compared with white patients, the team reports in the September 15th issue of Cancer released online August 13th.

The mortality odds ratio for black women was 1.56 compared with white women after adjusting for age and tumor size, number of positive lymph nodes and distant metastases. The investigators conclude that "adjusting for within-stage differences in tumor size and lymph node status did not appear to reduce the racial disparity."

Co-author Russell McBride told Reuters Health that "because of the limitations of the SEER database," his team cannot determine if there are any clinical implications of the findings.

"We know that triple-negative cancers are more common in African American women," he noted. "I would suspect there are a number of negative exposures in the course of life (in African American women) that increase risk of triple-negative cancers."

The next step, McBride commented, "is to determine if the racial disparity is connected in any way to the quality of care received once the cancer is detected."

As he explained, "It is important to rule out modifiable risk factors (such as quality of care) to ensure that the treatment is the same. Determining biological differences will be a little harder."