Diagnosis and prevention of breast cancer in women at high risk.

Abstract

Abstract Abstract #MS1-3 The definition of women at highest risk is those possessing a genetic mutation establishing a defined high risk. These and women at high risk by family history but lacking geneticly defined risk should undergo surveillance by MRI as well as mammography. This should begin ten years prior to their youngest first degree relative with breast cancer. Because early stage ovarian carcinoma is so difficult to detect, women with BRCA1 or 2 mutations should be encouraged to have salpingo-oophorectomy as soon as childbearing is finished. Premenopausal oophorectomy will cut the annual risk of breast cancer in half. This means that the risk of breast cancer in the next year is not astronomical, affording the opportunity to make very deliberate decisions about possible prophylactic surgery. With the added safety of MRI surveillance, many women will delay prophylactic surgery for a time, some will never elect it. The additional benefit of tamoxifen in this setting is controversial.
 Women with known mutations who develop breast cancer will generally elect mastectomy and have the considerations of contralateral prophylactic mastectomy previously reviewed. Breast conserving surgery is an option that is valid, however, and several studies have shown good results at 5 and 10 years. For those electing mastectomy for breast cancer, the options and standards are those for any woman with the same stage of disease.
 Women without a genetically defined high risk can be followed with MRI/mammographic surveillance, participate in chemo-prevention programs, and be spared prophylactic surgery.
 Prophylactic mastectomy should be preceded by MRI and mammograms to minimize risk of an unexpected finding of breast cancer. Even when these studies are clear, a good case can be made for performing sentinel lymph node biopsy at the time of the mastectomy so that the discovery of an occult breast cancer need not raise the issue of later axillary dissection for staging. With those caveats, prophylactic mastectomy is a total mastectomy and can be either skin sparing or nipple sparing. The former provides the lowest risk of breast cancer arising in residual breast and seems preferable. Nipple sparing prophylactic mastectomy has minimal data on long term effectiveness in this population. Much of the reason for sparing the nipple skin is cosmetic and experts in breast reconstruction are not uniform in believing that there is any improvement in aesthetics with a spared-nipple over a neo-nipple if the breast tissue beneath the spared-nipple was adequately removed [it is basically a full thickness skin graft over the reconstruction tissue]. With skin sparing mastectomy the flaps must be sufficiently thin to virtually [completely is impossible] eliminate all breast tissue. The pectoralis fascia is taken for the same reason. Depending upon breast volume, sub-muscular expanders, latissimus myo-cutaneous flaps, or TRAM flaps may be used to provide the feeling of normal breast tissue and a new blood supply for the spared skin. The cosmetic result should be excellent. Citation Information: Cancer Res 2009;69(2 Suppl):Abstract nr MS1-3.