Hereditary-ovary breast cancer syndrome ( HBOC ) is a cancer syndrome that results in higher-than-normal rates of breast and ovarian cancer in genetically related families (either one has both, or some individuals in the pedigree have one or another disease). Hereditary factors can be proven or suspected to cause the pattern of incidence of breast and ovarian cancer in the family.
Video Hereditary breast-ovarian cancer syndrome
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A number of genes are associated with HBOC. The most common causes of HBOC causes are:
- BRCA mutations: Harmful mutations in the BRCA1 and BRCA2 genes can produce very high rates of breast and ovarian cancers, as well as increased rates of other cancers.. Mutations in BRCA1 are associated with 39-46% of ovarian cancer risk and mutations in BRCA2 are associated with 10-27% of ovarian cancer risk.
Other identified genes include:
- TP53 : Mutations cause Li-Fraumeni syndrome. This results in very high breast cancer rates among young women with mutated genes, and although rare, 4% of women with breast cancer under age 30 have mutations in this gene.
- PTEN : Mutations cause Cowden syndrome, which produces hamartoma (benign polyps) in the colon, skin growth, and other clinical signs, as well as an increased risk for many cancers.
- CDH1 : Mutations associated with lobular breast cancer and gastric cancer.
- STK11 : Mutations produce Peutz-Jeghers syndrome. It is very rare, and creates a predisposition for breast cancer, colon cancer, and pancreatic cancer.
- CHEK2 : About one in 40 northern Europeans have mutations in this gene, making it a general mutation. Considered as a moderate-risk mutation, it can double or triple the risk of carrier breast cancer, and also increase the risk of colon cancer and prostate cancer.
- ATM : Mutations cause ataxia telangectasia; female carriers have about twice the normal risk of developing breast cancer.
- PALB2 : Studies vary in their estimates of the risks of mutations in this gene. This may be medium risk, or as high as BRCA2 .
About 45% of HBOC cases involve unidentified genes, or multiple genes.
Maps Hereditary breast-ovarian cancer syndrome
Prevention
People with BRCA1 and BRCA2 mutations are recommended to have a transvaginal ultrasound 1-2 times per year. Screening with CA-125 is also recommended. Salpingo-oophorectomy prophylaxis (removal of ovaries and Fallopian tubes to prevent cancer) is recommended at age 35-40 for people with a mutation of BRCA1 and at age 40-45 for people with BRCA2 mutation.
References
External links
Source of the article : Wikipedia
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