“If there is a mutation in the BRCA gene, the risk of developing breast cancer increases up to 80%, so an adequate prevention and screening plan is necessary.”
Professor Gwanghyeon Yoon of the Department of Surgery at Gangneung Asan Hospital Cancer Center said this about hereditary breast cancer.
Breast cancer, a malignant tumor of the breast, is a disease that affected 2.3 million people worldwide in 2020, causing approximately 690,000 deaths. About a quarter of women who develop cancer are affected by breast cancer, and the number of patients is so high that about a sixth of all female cancer deaths are due to breast cancer.
In Korea, the incidence of breast cancer continues to increase. According to the national cancer registration statistics released by the Ministry of Health and Welfare, the number of breast cancer cases in 2011 was 16,261, but it is increasing every year, reaching 28,861 in 2021.
The causes of breast cancer are largely divided into hereditary breast cancer, familial breast cancer, and sporadic breast cancer. Among them, hereditary breast cancer accounts for about 10% of all breast cancers and is caused by mutated genes inherited from parents.
◇ What is a gene?
Inside cells, which are the most basic units that make up our body, there are structures called chromosomes. Humans have 46 chromosomes (23 pairs). It contains genetic information inherited from parents. Genes play a role in storing and transmitting genetic information through a double helix structure.
◇ Inhibitor of the malignant tumor “BRCA gene”
Our body undergoes a complex process in which cells constantly proliferate and replicate, and in this process sometimes errors occur that develop into cancer cells.
Cancer cells divide at an abnormally fast rate and proliferate without limit. The Braca gene works to suppress indiscriminate cell division or cause abnormal cells to die on their own. In other words, it is a tumor suppressor gene that plays a role in correcting errors during cell division.
If the Braca gene, which plays this role, is changed by the mutation and cannot perform its function smoothly, errors accumulate and malignant tumors occur.
Professor Kwang-Hyeon Yoon said: “Many people believe that the Braca gene causes breast cancer,” adding: “In fact, the Braca gene plays an important role in suppressing the development of malignant tumors.”
◇ Increases the risk of developing cancers other than breast cancer.
Breast cancer caused by mutations in the Braca gene usually has a young age of onset, and bilateral breast cancer is common. In addition, many people have a family history of breast cancer, ovarian cancer, or pancreatic cancer.
It is known that if a mutation is present, the risk of breast cancer increases by about 40%-80% and the risk of ovarian, pancreatic, uterine, cervical and fallopian tube cancers also increases.
Professor Kwang-Hyeon Yoon said: “Whether a specific disease will appear due to a genetic mutation is determined by ‘penetrance’. Penetrance refers to the chance that a genetic mutation will develop into a real disease. Penetrance is “very high, so if there is a mutation, there is a significant chance that it will develop into breast cancer,” he said.
◇ Who is tested for genetic mutation?
The Braca gene mutation test is simple. It can be confirmed through a blood test and the test only needs to be done once in a lifetime.
However, since certain conditions must be met for health insurance to apply, testing is not recommended for everyone.
▲If a person diagnosed with breast cancer has at least one family member or relative (within the 3rd degree of kinship) who has been diagnosed with a specific malignant tumor (breast cancer, ovarian cancer, male breast cancer, metastatic prostate cancer, pancreatic cancer) ▲Diagnosed with breast cancer before the age of 40 The following conditions must be met: ▲Diagnosed with triple-negative breast cancer at or before the age of 60 ▲Bilateral breast cancer ▲Male breast cancer.
Additionally, family members of breast cancer patients with confirmed mutations of the Braca gene are also tested.
Professor Kwang-Hyeon Yoon said, “Hereditary breast cancer is a disease that appears in adulthood,” and “It is advisable to conduct gene mutation testing after you become an adult, when you fully understand the pros and cons of testing and can make your own decisions.”
◇ What if you are a “breast cancer gene mutation carrier”?
For “breast cancer gene mutation carriers” (people who have a Braca gene mutation but have not developed breast cancer), a personalized plan for the start time and frequency of screening is needed, taking into account family history.
For people over the age of 25, it is recommended to have a breast magnetic resonance imaging (MRI) once or twice a year. After the age of 30, it is recommended to have a mammogram and breast MRI every year.
Professor Kwang-Hyeon Yoon said: “In the case of breast MRI, it can be affected by changes in the mammary glands depending on the menstrual cycle, so it is most appropriate to perform it from the 7th to the 15th day of the menstrual cycle.”
For ovarian cancer, it is recommended to have a transvaginal ultrasound and blood tests with ovarian cancer tumor markers starting at age 30. If you have a family member with ovarian cancer, it is best to start screening at least 5 years before the age at which ovarian cancer was diagnosed.
Breast cancer caused by mutations in the Braca gene has a similar prognosis to breast cancer caused by other causes, so a very good outcome can be expected if detected early.
◇ If breast cancer has not yet occurred, will prophylactic mastectomy be useful?
The purpose of preventive surgery for carriers is to reduce the incidence and mortality of breast and ovarian cancer. Types of surgery include “prophylactic mastectomy” and “prophylactic bilateral salpingo-oophorectomy”.
Professor Kwang-Hyeon Yoon said: “Prophylactic mastectomy is considered an effective method to suppress the occurrence of breast cancer, but there is still not enough evidence to improve survival time.” and loss of confidence. “This can happen,” he said.
Considering these circumstances, prophylactic resection of the normal breast is not recommended for carriers who have not developed breast cancer.
Instead, “prophylactic bilateral salpingo-oophorectomy,” which removes the ovaries and fallopian tubes, is often recommended. This is because it reduces the incidence of not only breast cancer, but also ovarian and fallopian tube cancer. It is usually considered between the ages of 35 and 40, or after completion of child planning.
Professor Gwang-Hyeon Yoon of the Department of Surgery at Gangneung Asan Hospital Cancer Center said, “As the incidence of breast cancer has increased recently, many people have a vague fear of breast cancer. The most important thing is to accurately determine the condition through individual risk assessment and personalized testing. “It is all about establishing the right prevention and screening plan,” he emphasized.
onemoregive@newspim.com
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