Occult Breast Cancer Presenting as Metastatic Adenocarcinoma of Unknown Primary: Clinical Presentation, Immunohistochemistry, and Molecular Analysis

摘要: We report a rare presentation of 66-year-old female with diffuse metastatic adenocarcinoma unknown primary involving liver, lymphatic system and bone metastases. The neoplastic cells were positive for CK7 OC125, while negative CK20, thyroid transcription factor 1, CDX2, BRST-2, chromogranin, synaptophysin, estrogen receptor (ER), progesterone (PR), human epidermal growth 2 (HER2/neu). Fluorescence in situ hybridization showed no amplification the HER2/neu gene. Molecular profiling reported breast cancer origin very high confidence score 98%. absence immunohistochemistry staining ER, PR, further classified her as triple-negative cancer. Additional studies revealed expression levels topoisomerase (Topo) I, androgen receptor, ribonucleoside-diphosphate reductase large subunit; results thymidylate synthase, Topo II-α O6-methylguanine-DNA methyltransferase. patient was initially treated combination regimen cisplatin etoposide, she experienced rapid resolution cancer-related symptoms. Unfortunately, therapy complicated by cerebrovascular accident (CVA), which thought to be related serum mucin. After recovery from CVA, successfully second-line chemotherapy based on tumor profile. highlight role molecular diagnosis management this implication personalized challenging disease.