Studies Reveal Why Breast Cancer Hits Black Women Harder

Studies Reveal Why Breast Cancer Hits Black Women Harder
THURSDAY, Nov. 29 (HealthDay News) -- Biology and genetics --over and above socio-economic factors -- appear to influence how blackwomen fare after being diagnosed with breast cancer, U.S. researchers arereporting.
One new study found discrepancies in survival rates between blackbreast cancer patients and their white counterparts, indicating thatcancer screening guidelines may need to be revised.
A second study, conducted by researchers at the U.S. National CancerInstitute, found clear genetic differences in the breast cancer tumors ofblack women as compared with white women. This could influence how thedisease progresses and how it responds to therapy, the study authorssaid.
These findings are in line with previous research.
"Those of us who treat breast cancer every day are well aware thatAfrican-Americans just have a more aggressive breast cancer. Stage forstage, they do worse," said Dr. Brenda J. Sickle-Santanello, seniormedical director of Breast Health Services at Ohio Health and medicaldirector of oncology at Grant Medical Center in Columbus.
"African-Americans are underrepresented in research studies. I hopethis will heighten awareness to people who do the research to try andtarget African-American populations," she added.
The new studies and other research documenting racial disparities inbreast cancer are being presented this week at the American Associationfor Cancer Research conference on The Science of Cancer Health Disparitiesin Racial/Ethnic Minorities and the Medically Underserved, in Atlanta.
Differences in breast cancer survival rates between black and whitewomen are often attributed to non-biological reasons, such as access tohealth care and various socio-economic factors. While these factors are nodoubt important, a growing body of research also points to biologicalexplanations that may account for the differences.
Black women tend to have more aggressive, estrogen-receptor-negativebreast tumors that don't respond to newer hormonal therapies, experts say.They also tend to have a higher rate of lymph node involvement.
The first study, by researchers at the University of Chicago, looked at1,246 women with stage I or stage II invasive breast cancer treated withlumpectomy and radiation.
Eight years after treatment, 84.9 percent of white women were alive andfree of disease, compared to 78.1 percent of black women. Similarly, 31.6percent of black women experienced a relapse at this point in time, versus14.9 percent of all other women.
Current screening mammography guidelines might need to be revised tobenefit black women, the authors reported.
"Maybe we should be more aggressive in general and systemic therapy,even in screening," Sickle-Santanello agreed.
The second study identified differences in the gene profiles of tumors,including those involved with angiogenesis (blood vessel development) andhow tumor cells interact with the immune system.
Many of the same genes are active in inflammatory diseases such aschronic colitis. Previous studies have shown a link between theseinflammatory conditions and cancer.
Finally, a third study looked at whether various groups of women,including black women, were undergoing auxiliary lymph node dissection,which can indicate whether the breast cancer has spread to other parts ofthe body.
After plying data on close to 200,000 women, the investigators foundthat uninsured women were 24 percent less likely to have their lymph nodesassessed, compared to women with private insurance.
Women who lived in areas with low education levels were 13 percent lesslikely than those from high education areas to undergo the procedure, andblack patients were 10 percent less likely than white patients to havetheir lymph nodes accurately assessed.
Age was also a factor, with women 73 or older three times less likelyto get the procedure, compared with women aged 51 or younger. Lymph nodedissection is considered optional for elderly women but, even so, theresearchers were surprised by the size of the discrepancy.
Overall, 11 percent of patients in the database did not undergo theprocedure.
"In general, there shouldn't be a non-clinical reason that influenceswhether or not patients receive this important diagnostic procedure," saidDr. Michael Halpern, study lead author and strategic director of healthservices research at the American Cancer Society. "We don't have any ideaon exactly why this happens. Our guess is that there are a number ofbarriers related to communication between patients and physicians."
More information
The American CancerSociety has more on race, ethnicity and breast cancer.