Young Women With Mutant Breast Cancer Genes Have High Rates of Relapse After Cancer Treatment
Oct. 7, 1999 (New York) -- A new study is raising questions regarding the best treatment option for young breast cancer patients with mutations of either of the two so-called "breast cancer genes," BRCA1 and BRCA2. The findings show that of such patients, those who have been treated with radiation and have had part of their breast removed along with their tumor (lumpectomy) have a high risk of developing additional breast cancer in the same breast eight years later. The study appears in the October issue of the Journal of Clinical Oncology.
"The bottom line from this paper is that [the combination of lumpectomy and radiation] is still a reasonable alternative for women who do have a mutant version of BRCA1 or BRCA2; they just need to have very close follow-up," lead author Bruce Turner, MD, tells WebMD. "These women and their physicians need to be aware that there is this risk of developing not only [cancer in the opposite breast] but also of developing a recurrent or new primary breast cancer in that same breast." Turner is an assistant professor of radiation oncology at Thomas Jefferson University Hospital in Philadelphia. "These women need to be seen by their physician frequently -- yearly, if not biyearly -- they need to undergo frequent mammograms, and in young women with dense breasts which are difficult to actually see [with a mammogram], some may need to undergo an annual or biannual MRI." An MRI is a very detailed computerized X-ray.
Along with radiation therapy, lumpectomy is the preferred standard of care for the majority of early-stage breast cancer patients with or without genetic mutations.
In the 14-year study, all women with BRCA1/2 mutations who had a second cancer underwent mastectomy at the time the new tumor was detected and all remain alive. "These findings are significant because drugs like tamoxifen, or other estrogen reception modulators, that prevent second tumors can perhaps be prescribed earlier," says co-author Bruce G. Haffty, MD, in a news release issued by Yale University School of Medicine, where he is an associate professor of therapeutic radiology. However, Turner points out that studies suggest that the majority of BRCA1/2 tumors are not susceptible to these drugs, although much data remain to be collected from ongoing trials.
Turner, Haffty, and colleagues studied 104 women treated with lumpectomy and radiation, 52 of whom developed a return of cancer in the treated breast and 52 who did not. Among the 52 patients with return of cancer, 15% had BRCA1 or BRCA2 mutations. When incidence of BRCA1/2 mutations was compared by age, 40% of the women under age 40 had the damaged genes, compared with just 5.2% of women over age 40.
The median time to return of cancer was eight years in women with a BRCA1/2 mutation, compared with five years in women without mutations. The longer time to return of cancer in BRCA1/2 carriers suggests that the new tumors are developed out of tissue left in the breast after the lumpectomy that still harbors the mutated genes rather than a reactivation of the old treated cancer.