Pittsburgh: More women are opting for having both breasts removed after a diagnosis of cancer in just one breast, but a new study says that won't make a difference in survival rates.
According to the study, released on Tuesday by the Stanford University School of Medicine and the Cancer Prevention Institute of California and published in the Journal of the American Medical Association, women who chose a double mastectomy had similar survival rates to those who had the more targeted procedure of lumpectomy. That's when just the malignant tumour is removed, followed by radiation.
Ten-year survival rates were roughly the same – about 82 per cent – for women who had lumpectomies plus radiation and for women who had double mastectomies. Women who had a unilateral mastectomy had slightly lower survival rates.
The researchers found that most women choosing double mastectomies are white, have private insurance and receive treatment at a National Cancer Institute-designated cancer centre. In 2011 alone, 33 per cent of women with cancer in one breast under age 40 opted to remove both breasts, compared with 3.6 per cent in 1998.
The study confirms what medical professionals have suspected, said Dr Kathleen Erb, a breast cancer surgeon at Allegheny General Hospital. "It tells us what we felt was true – there is no survival benefit to removing an unaffected breast, except in special cases."
Those cases would include women who tested positive for the so-called BRCA1 or BRCA2 genes or other mutations. A genetic predisposition may mean that a double mastectomy can lower risk significantly, even if cancer hasn't been diagnosed yet, said Dr Kandace McGuire, a surgeon who is director of the pre-menopausal breast cancer program at Magee-Women's Hospital of UPMC.
The analysis of nearly 190,000 California women with the disease doesn't break down different types of breast cancers, but it is the first to directly compare survival rates following the three most common breast cancer surgeries: bilateral mastectomy, unilateral mastectomy and lumpectomy plus radiation. Women in the study were diagnosed between 1998 and 2011 with cancer in one breast.