Core biopsy of a well-circumscribed breast lump in a 32-year-old woman shows sheets of high-grade pleomorphic cells with a prominent lymphoplasmacytic infiltrate and syncytial growth pattern. Which statement about this tumour is correct?
- A It is strongly associated with BRCA1 germline mutations ✓
- B It carries a worse prognosis than grade-matched invasive ductal carcinoma
- C It is almost always HER2 positive
- D It metastasises early to bone
Correct answer: A. It is strongly associated with BRCA1 germline mutations
Explanation
The described morphology is medullary carcinoma: syncytial sheets of high-grade cells with dense lymphocytic infiltrate and pushing margins. Despite its high histological grade it has a relatively better prognosis than ordinary ductal carcinoma, making option B wrong. It is classically ER negative, PR negative and HER2 negative, ruling out option C, and haematogenous spread patterns are not characteristically early osseous involvement. Its strong association with BRCA1 mutations, particularly in young women, is the tested fact.
Reference: Robbins and Cotran Pathologic Basis of Disease, 10th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
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