Hereditary Breast Cancer
All breast cancers are due to mutations (changes ) in the genes.
If these changes (mutations) are acquired at the time of birth from the parents, then that cancer is called Hereditary Breast Cancer. These are relatively small in number, and the majority of the breast cancers are due to mutations acquired after birth. They could be because of the lifestyle, pollution, age and so on.
Hereditary breast cancer accounts for approximately 5–10% of all breast cancer cases. Identifying hereditary breast cancer is essential for tailoring prevention, screening, and treatment strategies for affected individuals and their families.
Some of the common genes know to be hereditable are BRCA 1, 2, PAL B2, PTEN, TP53, CHEK2 & CDH1.
Key Characteristics of Hereditary Breast Cancer
Simple Tissue Rearrangement:
- Early Onset: Often diagnosed at a younger age (before 50 years).
- Family History: Multiple relatives with breast, ovarian, or other associated cancers.
- Bilateral Cancers: Higher likelihood of bilateral breast cancer or multiple primary cancers.
- Rare Cancer Types: Includes male breast cancer, medullary breast cancer, or other specific subtypes.
- Associated Cancers: Linked to ovarian, pancreatic, prostate, and other cancers depending on the mutation.
Hereditary Breast Cancer is not more aggressive than other breast cancer and hence these patients will have outcomes similar to others. They are suitable for breast conservation surgeries like regular breast cancer patients.
Implications of Positive result of Gene testing in a Diagnosed Breast Cancer Patient.
| Before Initiation of Treatment | After Completion of Treatment |
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Treatment Decisions about Surgery _ Risk reducing Oopherectomy & Fallopian Tube removal |
Enhanced screening would be done using MRI in addition to Mammogram |
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Treatment Decisions about Chemotherapy – Specific molecules could be used like PARP inhibitors |
Screening for other cancers like Ovarian, Pancreatic and prostratic cancers |
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Avoidance of Radiation in TP53 Mutations |
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Followup intensity |
Risk reduction surgeries for the opposite breast, Salpingo Oopherectomy |
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Management of Family Members risk assessment and screening on a regular basis |
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Life Style Modifications |
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Implications of Gene Positivity in a lady without Breast Cancer is to institute regular Screening to Prevent development of Hereditary Breast Cancer
1. Enhanced Screening
- Annual mammography starting at age 25–30 or earlier based on family history.
- Annual breast MRI for high-risk individuals, as it detects cancers missed by mammograms.
- Routine screening for other associated cancers (e.g., ovarian, pancreatic, prostate).
2. Risk-Reducing Strategies
- Prophylactic Surgery:
- Risk-reducing mastectomy can lower breast cancer risk by 90–95%.
- Salpingo-oophorectomy (removal of ovaries and fallopian tubes) reduces ovarian cancer risk and may lower breast cancer risk in premenopausal women.
- Chemoprevention::
- Use of tamoxifen or raloxifene for hormone receptor-positive breast cancer risk reduction.
- Lifestyle Modifications:
