The diagnostic utility of Merkel cell polyomavirus immunohistochemistry in a fine needle aspirate of metastatic Merkel cell carcinoma of unknown primary to the pancreas.
Long LiKyle MolbergNaga CheedellaJoel ThibodeauxStacy HinsonElena LucasPublished in: Diagnostic cytopathology (2017)
Merkel cell carcinoma (MCC) is an aggressive skin tumor with a high tendency for metastases. We report a case of MCC initially presenting as axillary and pancreatic metastases. A 33-year-old HIV-positive Hispanic male presented with a history of a rapidly growing axillary mass. A needle core biopsy demonstrated an epithelioid neoplasm composed of small to medium-sized cells with high nuclear-cytoplasmic ratio, nuclear molding, and frequent mitotic figures. A subsequent PET scan revealed a 1.5 cm FDG avid mass in the pancreas. Endoscopic ultrasound-guided FNA of the pancreatic mass showed neoplastic cells with similar morphology to those of the axillary mass. The tumor cells were positive with pancytokeratin AE1/AE3, CK20, CD56, synatophysin, chromogranin, and Merkel cell polyomavirus (MCPyV). This case of MCC most likely originated from a resolved primary skin lesion drained by the involved axillary lymph node with subsequent metastases to the pancreas and distant lymph nodes.
Keyphrases
- ultrasound guided
- lymph node
- fine needle aspiration
- hiv positive
- sentinel lymph node
- induced apoptosis
- single cell
- neoadjuvant chemotherapy
- cell cycle arrest
- computed tomography
- cell therapy
- men who have sex with men
- south africa
- squamous cell carcinoma
- small cell lung cancer
- air pollution
- pet imaging
- antiretroviral therapy
- pet ct
- soft tissue
- endoplasmic reticulum stress
- stem cells
- positron emission tomography
- cell death
- cell cycle
- oxidative stress
- wound healing
- early stage
- bone marrow
- cell proliferation
- hepatitis c virus
- protein kinase