African American women are more likely to die of breast cancer than their white counterparts because they tend to get the disease earlier, suggests new research from an international team of researchers. The racial disparity in mortality rates from breast cancer first appeared in the 1970s, coinciding with the introduction of mammography. The average age of breast cancer diagnosis in African American women is 46, compared with 57 for European Americans.
The new research, published in The International Journal of Surgery, suggests that the reason for this is not reduced access to medical care, but because surgery in pre-menopausal women could encourage growth of the cancer.
"Surgery to remove a primary tumor induces the formation of new blood vessels -known as angiogenesis. In pre-menopausal women who have high levels of estrogen and other hormones, this may encourage the growth of the tumor," said researcher Dr Isaac Gukas, of the University of East Anglia, UK. "Early detection, through mammography, is more effective in post-menopausal women, and more white women are diagnosed after the menopause. This could explain the disparity in mortality."
It was Dr Gukas's experience as a clinician treating breast cancer in Africa that led him to form the hypothesis that surgery-induced angiogenesis might explain the very high early mortality and generally poor outcome of patients in that part of the world. "We do not intend to oversimplify this subject, but it seems clear that at least part of the phenomenon of widening mortality along racial lines could be attributed to surgery leading to accelerated tumor growth in pre-menopausal women," he explained.
If proven, the new hypothesis has implications for all women with breast cancer, especially pre-menopausal women. "We do not have enough evidence to alter treatment at present and younger women should not be deterred from having surgery. But, if further studies confirm our hypothesis, we may need to give them appropriate chemotherapy, including angiogenesis inhibitors, beforehand to ensure the best outcome," concluded Dr Gukas.
Source: University of East Anglia
