Male Breast Cancer Mortality Higher Among Black Patients

NEW YORK, March 19 -- Men with breast cancer show the same racial disparities in survival as do women with the disease, according to a small population-based study.

Medicare-age black men with breast cancer were three times more likely to die from the disease than white men (hazard ratio 3.29, 95% confidence interval 1.10 to 9.86), said Dawn L. Hershman, M.D., M.S., of Columbia University, and colleagues.

These findings parallel those of previous studies among women, which have shown higher breast cancer mortality rates for black women at all ages, they wrote in a study published online March 16 in the Journal of Clinical Oncology.

"Racial disparities in breast cancer outcomes between black and white women have been attributed to advanced stage at diagnosis, negative HR [hormone receptor] status, higher tumor grade, reduced access to health care, and other socioeconomic factors," they added.

"Similar factors may contribute to the poor outcomes we observed among black men with breast cancer," they continued.

The researchers used data from the linked Medicare and Surveillance, Epidemiology, and End Results (SEER) database. The analysis included 510 men ages 65 and older with early stage, histologically confirmed breast cancer diagnosed between 1991 and 2002.

The study included a relatively small sample of black patients (455 white, 34 black).

Nearly all patients underwent mastectomy (94%) while the remaining 6% underwent lumpectomy. About 28% received adjuvant chemotherapy, and 29% received radiation therapy.

During the average 58.5 months of follow-up, 242 men died. There were 39 breast-cancer-specific deaths among white patients (12.7%) and eight among black patients (30.8%).

Among the findings, the researchers reported:

• Black men were more likely to have later-stage disease (P=0.0404) and larger tumors (P=0.0108) than white men,
• Black men tended to be less likely to have hormone receptor-positive disease (56% versus 72%, P=0.1223),
• Five-year survival was about 90% among white patients but 66% among black patients,
• Men who underwent mastectomy had 56% lower overall mortality (hazard ratio 0.44, 95% CI 0.26 to 0.74) and 89% lower disease-specific mortality compared with lumpectomy (HR 0.11, 95% CI 0.03 to 0.38), and
• Black men were 48% less likely to be referred to a medical oncologist and 56% less likely to receive chemotherapy than white men, though neither difference was significant (P=0.1808 and P=0.5430, respectively).

On the basis of the findings, the researchers concluded that part of the racial disparity in survival may be due to differences in treatment.

The study could not look at how many patients received hormonal therapy because oral therapies were not billed by Medicare for inclusion in the database.

However, there was a numeric difference in chemotherapy treatment and hormone receptor status between the races, which the authors said, "may not have reached statistical significance because our sample included only 34 black men."

"Given the high prevalence of hormone receptor positivity in male breast cancers, these patients may derive more benefit from adjuvant hormonal therapy than from chemotherapy," Dr. Hershman and colleagues wrote.

"Given their adverse staging and hormone status, black men should have been more likely than white men to receive chemotherapy," they added. "Undertreatment may, therefore, account for the racial disparity in breast cancer-specific survival among men."

Further studies with larger populations will be needed to explain clinical and biological factors contributing to racial disparities in male breast cancer, they said.

Because male breast cancer is rare at less than 1% of cancers in men, obtaining large sample sizes has been a challenge. Most previous studies have been small, single center, retrospective series.