Breast cancer in multiple endocrine neoplasia type 1 (MEN1).

摘要: Summary A 38-year-old female was identified as carrying a heterozygous pathogenic MEN1 variant (c.1304delG) through predictive genetic testing, following diagnosis of familial hyperparathyroidism. Routine screening for parathyroid and pituitary disease negative. However, cross-sectional imaging by CT revealed 41 mm pancreatic tail mass. Biopsy via endoscopic ultrasound confirmed the lesion to be well-differentiated (grade 1) neuroendocrine tumour (pNET) with MIB1<1%. Biochemically, hyperinsulinaemic hypoglycaemia an overnight fast, which subsequently managed diet alone prior definitive surgery. Pre-operative work-up octreotide SPECT demonstrated avid tracer uptake in and, unexpectedly, focal area left breast. Further investigation, subsequent mastectomy, ductal carcinoma situ pT2 (23 mm) grade 1, N0 (ER positive; HER2 negative). Following our patient underwent successful distal pancreatectomy resect pNET. Loss heterozygosity (LOH) at locus found both breast pNET, thereby keeping 'two-hit' hypothesis oncogenesis, suggestive but non-definitive clue causation. To obtain further support causative relationship between cancer, we undertook detailed review published literature overall supports notion that cancer is MEN1-related malignancy presents younger age histologically, typically subtype. Currently, clinical guidance regarding surveillance does not exist research required establish cost-effective strategy). Learning points We describe case pNET diagnosed young 38 years who variant. wild-type allele seen tissue specimen. Breast may under-recognised MEN1-associated than general population relative risk 2-3. determine cost-effectiveness approach patients .