NEW YORK, May 6 (Reuters Life!) - Recent U.S. changes to guidelines for mammography breast cancer screening may prevent women in their 40s, and specifically minority women, from receiving early breast cancer diagnoses, two U.S. studies suggest.
The U.S. Preventive Services Task Force no longer advises women in their 40s to get routine screening mammograms.
But one of the two studies, a 10-year retrospective analysis from the University of Missouri at Columbia, showed that mammograms detected smaller tumors, with less spreading to nearby lymph nodes, in women in their forties than manual breast exams could.
Minority women were also more likely to develop cancers in their forties than white women, according to data reviewed by researchers at Loma Linda University in California.
"For some Asian women and other minorities, the peak incidence (of breast cancer) is a decade earlier. The guidelines are not ethnicity-specific," said Sheldon Feldman, chief of breast surgery at Columbia University Medical Center in New York and chairman of the American Society of Breast Surgeons publication committee.
"That's an important point. Whether or not you agree with the general recommendations for average groups, then certainly for minorities and certain subgroups, those recommendations need to be altered."
The two studies were presented at the annual meeting of the society last week. Feldman was not involved in either study.
Researchers at the University of Missouri reviewed data on 1,581 breast cancer patients and identified 311 who were aged 40-49, with 47 percent diagnosed with a mammogram.
The median tumor diameter was 20 mm in the mammogram group, compared to 30 mm in the non-mammogram group. Women in the mammogram group also had a lower rate of spread to the lymph nodes, 25 percent against 56 percent.
And, five years after diagnosis, women in the mammogram group were more likely to be free of the disease, 94 percent to 71 percent, and have a better overall survival rate.
A separate study showed that minorities seem to make up a disproportionate number of the younger women who might benefit from mammograms.
Sharon Lum and her team at Loma Linda University used the California Cancer Registry to identify 46,691 patients aged 40 to 74 who were diagnosed with certain kinds of breast cancer from 2004 to 2008.
Among the women in their forties, Hispanics were most likely to receive the cancer diagnoses, followed by Asians and Pacific Islanders. Non-Hispanic black women had more diagnoses of one form of the cancer and fewer of the other.
"The implementation of the... guidelines would disproportionately impact non-white women and potentially lead to more advanced presentation at diagnosis," Lum and her team wrote.
Breast cancer kills around 500,000 people globally each year and is diagnosed in close to 1.3 million people annually. (Reporting by Rob Goodier at Reuters Health; editing by Elaine Lies)