The presence of pathogenic variants in the BRCA1 and BRCA2 genes are relevant risk factors for the development of breast and ovarian cancer in women. Moreover, they not only predispose to these tumour types, but also contribute to the likelihood of developing prostate cancer in men and increase the risk of pancreatic cancer in both sexes.
Familial breast cancer (BRCA1 and BRCA2 genes)
Breast cancer is a malignant tumor that originates in the tissue of the mammary gland. When the cancerous cells originate in the glandular tissue of the breast and have the capacity to invade the surrounding healthy tissues, we speak of breast cancer. Worldwide, it is the most frequently diagnosed malignant tumor and the leading cause of cancer death in women.
It is estimated that between 5% and 10% of breast cancers are hereditary and follow an autosomal dominant pattern of inheritance. Familial breast cancer or hereditary breast cancer (HBC) is due, in most cases, to a mutation in the BRCA1 or BRCA2 genes.
Symptoms
HBC is characterized by an increased risk of male and female breast cancer, an increased predisposition to ovarian and fallopian tube cancer in women and, to a lesser extent, increased risk of other types of cancer, such as prostate cancer in men, pancreatic cancer and melanoma.
Symptoms that may indicate the presence of breast cancer include:
- A lump or area of thickened tissue in the breast, upper chest or armpit.
- Skin changes, such as wrinkling or dimpling.
- A change in the color of the breast, which may appear red or swollen.
- Changes in the nipple, for example, it has retracted (inverted).
- Rashes (eczema-like), scaling, or crusting on or around the nipple.
- Unusual fluid (discharge) from the nipples.
- Changes in the size or shape of the breast.
- The most common symptom of breast cancer in men is a lump in the breast area.
Disease management
Screening for breast cancer at an earlier age and annual follow-up (mammography and screening with MRI or MRI) are recommended.
Prophylactic surgery (bilateral mastectomy and salpingo-oophorectomy) or chemoprevention with drugs such as tamoxifen and raloxifene may be used in those at increased risk of cancer.
Genes analyzed
Bibliography
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