Thursday, July 14, 2016

Genetic Risk of Breast Cancer and Your Options

Cancer News in Context is excited to publish four posts this week on high-risk breast and ovarian cancer.  These posts will provide insight for women (and their families) from Washington University School of Medicine physicians on unique aspects of high-risk disease -- from genetic testing and treatment to prevention and risk management.  
July 11 - Overview: High-Risk Breast Cancer - Prevention and Risk Management
July 12 - High-Risk Ovarian Cancer: Identifying, Preventing, and Managing Risk
July 13 - Treating and Managing Future Risk in Women with Hereditary Breast Cancer
July 14 - Genetic Risk of Breast Cancer and Your Options
--      --     --

by
Elizabeth B. Odom, MD 
Resident/Clinical Trainee, Division of Plastic & Reconstructive Surgery, Department of Surgery
Jennifer Yu, MD 
Resident, Division of Plastic & Reconstructive Surgery, Department of Surgery

Genes are the code that are passed down from ancestors that determine everything about us – hair color, eye color, body type, and every other characteristic that makes you an individual. These codes also determine our risk for certain types of cancer, and certain changes or mutations in the gene can change the risk of cancer developing over your lifetime. 

One gene that has been studied extensively is the BRCA gene mutation that has been linked to a high risk for breast cancer. Under one percent of women have this genetic mutation. The average chance of an American woman developing breast cancer in her lifetime is around 12 percent, and the risk of having cancer in both breasts is rare.(1) However, without treatment, women with the BRCA gene mutation have a lifetime risk of breast cancer development of over 50 percent with a higher likelihood of breast cancer occurring in both breasts.(2) 

There is no proven way to prevent breast cancer, but generally, exercise, healthy weight, a diet full of fruits and vegetables, and the avoidance of tobacco leads to lower rates of disease. Breastfeeding has also been found to be somewhat protective in the development of breast cancer. However, for all women, not just those genetically susceptible, breast cancer screening is key. All women should get an annual mammogram after the age of 45, then every 2 years after the age of 55 if no cancer has developed. Screening may start earlier if there is a history of early breast cancer in the patient’s family. 

Women with a strong family history of breast cancer in relatives before the age of 50, or those who have a male relative with breast cancer may be tested for the BRCA mutation through a blood test. They may also begin having mammograms as early as 25 years old. If the test is positive, due to the high risk for cancer, women are referred to a breast specialist to discuss their treatment options. 

In 2014, there was a study published that found women with the BRCA mutation who undergo removal of both breasts (bilateral mastectomy) at the time of breast cancer treatment had half the lifetime risk of dying from breast cancer than those who underwent removal of just the breast affected by cancer.(3) Furthermore, because of the increased risk, women such as actress Angelina Jolie, may choose to have both breasts removed to prevent the development of breast cancer. This has been shown to reduce the incidence of breast cancer significantly.(4) This decision is highly individual and options for continued screening or surgical intervention should be discussed thoroughly between the patient, family members, and the treating physician. 

However, preventative mastectomy is becoming an increasingly popular option, especially with the availability of breast reconstructive procedures using either your own tissue or implant devices. Women who elect to undergo a bilateral mastectomy to treat or prevent cancer are usually referred to a plastic surgeon to discuss the best reconstructive option for them. In many cases, the breasts may be reconstructed the same day as the mastectomy procedure. 

There is some increased risk of operative complications when having both breasts removed, however, after bilateral mastectomy and reconstruction, women no longer need to undergo annual mammogram screening, have less anxiety about the development of breast cancer, and are satisfied with the way their breasts look, particularly with clothing.(5) If you or someone you know is concerned about their risk of breast cancer, discuss this with your physician. There are well-known strategies of early detection and prevention, and the treatment options today are better than ever. 

References
1. Howlader N NA, Krapcho M, et al. (eds). SEER Cancer Statistics Review, 1975-2011, National Cancer Institute. Bethesda, MD, http://seer.cancer.gov/csr/1975_2011/ , based on November 2013 SEER data submission, posted to the SEER web site, April 2014. 
2. Levy-Lahad E, Friedman E. Cancer risks among BRCA1 and BRCA2 mutation carriers. Br J Cancer. 2007;96(1):11-5. Epub 2007/01/11. doi: 10.1038/sj.bjc.6603535. PubMed PMID: 17213823; PMCID: PMC2360226. 
3. Metcalfe K, Gershman S, Ghadirian P, Lynch HT, Snyder C, Tung N, Kim-Sing C, Eisen A, Foulkes WD, Rosen B, Sun P, Narod SA. Contralateral mastectomy and survival after breast cancer in carriers of BRCA1 and BRCA2 mutations: retrospective analysis. BMJ. 2014;348:g226. Epub 2014/02/13. doi: 10.1136/bmj.g226. PubMed PMID: 24519767; PMCID: PMC3921438. 
4. Lostumbo L, Carbine N, Wallace J, Ezzo J. Prophylactic mastectomy for the prevention of breast cancer. The Cochrane database of systematic reviews. 2004(4):CD002748. Epub 2004/10/21. doi: 10.1002/14651858.CD002748.pub2. PubMed PMID: 15495033. 
5. Koslow S, Pharmer LA, Scott AM, Stempel M, Morrow M, Pusic AL, King TA. Long-term patient-reported satisfaction after contralateral prophylactic mastectomy and implant reconstruction. Annals of surgical oncology. 2013;20(11):3422-9. Epub 2013/05/31. doi: 10.1245/s10434-013-3026-2. PubMed PMID: 23720070.

No comments:

Post a Comment