Potential Overuse of Contralateral Prophylactic Mastectomy
Women diagnosed with early stage breast cancer have several treatment options to choose from, all with excellent outcomes, and coming to a decision can be daunting.
Breast conserving surgery (commonly referred to as a lumpectomy) combined with radiotherapy constitutes breast conservation therapy and is often the recommended treatment option for women with early stage breast cancer. The alternative surgical option of mastectomy (removal of the entire breast tissue) can sometimes obviate the need for radiation. There is no survival difference between breast conservation therapy and mastectomy in women with early stage breast cancer. Therefore, the decision of whether to undergo a mastectomy in a woman who is a candidate for breast conservation therapy is a personal one, where concerns with body image or need for follow up testing may influence this decision.
A desire to minimize the risk of a second breast cancer in the opposite breast can lead women to pursue mastectomy of the unaffected, healthy (contralateral) breast as a precaution, called contralateral prophylactic mastectomy (CPM), also known as a double mastectomy. The rate of CPM is increasing among women with early stage breast cancer without an inherited risk of breast cancer. However, the choice to undergo a CPM in women without an inherited risk of breast cancer is controversial.
While CPM is strongly recommended for women who have increased risk for a contralateral breast cancer, such as those with a BRCA1 or 2 genetic mutation who may have an increased risk >10–25% in developing a second cancer in the opposite breast, the risk among women without an inherited risk of breast cancer is far lower: at 3–5% within 10 years of diagnosis. Additionally, CPM has no survival benefit in this subgroup of women. Moreover, CPM has higher surgical complication rates, including risks of wound healing or infection, longer hospital stays, longer recovery periods, possible need for multiple operations, and long-term risks of chronic pain or body image concerns. These surgical complications may delay the start of recommended chemotherapy and/or radiation regimens, which is problematic as the main driver in breast cancer survival is the potential for spread of the known breast cancer to distant organs rather than from the development of a second breast cancer in the opposite breast.
In light of these drawbacks, CPM in women without increased risk for contralateral breast cancer has been discouraged by several medical organizations and societies to avoid potential overtreatment at the expense of increased complications.
In women with early stage breast cancer without an inherited risk of breast cancer, the decision of whether or not to pursue a mastectomy of the opposite breast should involve discussion of potential benefits and risks with a physician. Ultimately, this shared decision making should empower women to help make these difficult decisions regarding cancer treatment and prevention. If CPM is pursued, it is often recommended to do so only after all cancer treatment is complete to avoid any delays in necessary treatment.