Practical
There are several programs to calculate the prevalence of BRCA mutations considering the clinical environment and family history of individuals.
http://www.myriadpro.com/brca-risk-calculator/calc.html http://www.ibreast.kr/BRCA/BRCA.html (Korean model) http://www4.utsouthwestern.edu/breasthealth/cagene
http://www.myriadpro.com/brca-risk-calculator/calc.html
http://www.ibreast.kr/BRCA/BRCA.html (Korean model)
http://www4.utsouthwestern.edu/breasthealth/cagene
The probability of harboring the BRCA genetic mutation according to the clinical environment is as follows:
The prevalence of BRCA mutation in high grade serous epithelial ovarian cancer is approximately 23% to 40% [ 15 16 ]. The prevalence of BRCA mutation in Korean ovarian cancer patients with a family history of ovarian cancer in a first degree relative is approximately 63% [ 17 ]. The prevalence of BRCA mutation in Korean ovarian cancer patients with a family history of breast cancer in a first degree relative is approximately 21% [ 17 ]. The prevalence of BRCA mutation in Korean ovarian cancer patients with a family history of ovarian or breast cancer in a first degree relative is approximately 33% to 61% [ 16 17 ]. The prevalence of BRCA mutation in Korean ovarian cancer patients without a family history of ovarian cancer in a first degree relative is approximately 9% to 13% [ 16 17 ].
The prevalence of BRCA mutation in high grade serous epithelial ovarian cancer is approximately 23% to 40% [ 15 16 ].
The prevalence of BRCA mutation in Korean ovarian cancer patients with a family history of ovarian cancer in a first degree relative is approximately 63% [ 17 ].
The prevalence of BRCA mutation in Korean ovarian cancer patients with a family history of breast cancer in a first degree relative is approximately 21% [ 17 ].
The prevalence of BRCA mutation in Korean ovarian cancer patients with a family history of ovarian or breast cancer in a first degree relative is approximately 33% to 61% [ 16 17 ].
The prevalence of BRCA mutation in Korean ovarian cancer patients without a family history of ovarian cancer in a first degree relative is approximately 9% to 13% [ 16 17 ].
For BRCA carriers, the need for strict adherence to screening schedules for peritoneal, ovarian, and fallopian tubal (POFT) cancers such as transvaginal sonograms or serum CA-125 tests every 4 months and frequent screening for POFT cancers might offer a better chance for early stage detection [ 18 ].
Transvaginal ultrasound and serum CA125 tests can be performed when the prevalence of POFT cancer is predicted to be more than 10% as follows [ 18 ].
Known carriers of one of the predisposing genes (BRCA1, BRCA2, MLH1, MSH2, MSH6, PMS1, or PMS2). Families with two or more individuals suffering from POFT cancer who were first-degree relatives. Families with one individual suffering from POFT cancer and one individual with breast cancer diagnosed at age <50 years who were first-degree relatives. Families with one individual suffering from POFT cancer and two individuals with breast cancer diagnosed at age <60 years who were first-degree relatives. Families with three individuals suffering from colorectal cancer, at least one of whom was diagnosed at age <50 years as well as one individual suffering from POFT cancer, and all of these individuals were connected by first-degree relationships.
Known carriers of one of the predisposing genes (BRCA1, BRCA2, MLH1, MSH2, MSH6, PMS1, or PMS2).
Families with two or more individuals suffering from POFT cancer who were first-degree relatives.
Families with one individual suffering from POFT cancer and one individual with breast cancer diagnosed at age <50 years who were first-degree relatives.
Families with one individual suffering from POFT cancer and two individuals with breast cancer diagnosed at age <60 years who were first-degree relatives.
Families with three individuals suffering from colorectal cancer, at least one of whom was diagnosed at age <50 years as well as one individual suffering from POFT cancer, and all of these individuals were connected by first-degree relationships.
If the patients are clinically suspected of POFT cancer, they should be assessed for a family history of POFT cancer and breast cancer. Genetic counseling and genetic testing are provided after pathological diagnosis. BRCA carriers should be counseled about risk-reducing bilateral salpingo-oophorectomy, ideally between 35 to 40 years and upon completion of child-bearing or in an individualized manner based on the earliest age of onset of ovarian cancer in the family.
Even in families with the BRCA mutation, the risk of developing POFT cancer or breast cancer in a woman under the age of 21 years is extremely low. Therefore, and considering the potential negative impact of genetic testing, the Korean Society of Gynecologic Oncology panel does not recommend genetic testing for women under the age of 21 years for hereditary breast and ovarian cancer in the absence of a family history of early-onset cancer.