Mediastinal small cell carcinoma with liver and bone marrow metastasis, mimicking lymphoma.
Primary mediastinal neuroendocrine tumors are a rare malignancy that accounts for < 10% of all mediastinal tumors. The case presented here involves a 52-year-old man who had been suffering for 3 mo from chronic cough, anorexia and substantial weight loss, as well as 2 wk of jaundice prior to his admission. A computed tomography scan showed a 4.3 cm × 6.6 cm mediastinal mass with multiple liver nodules scattered along both hepatic lobes. Endoscopic ultrasound showed a large heterogeneous hypoechoic mass at the mediastinum with multiple target-like nodules in the liver. Fine-needle aspiration specimens revealed numerous, small, round cells with hyperchromatic nuclei, scarce cytoplasm, and frequent mitotic features. Immunohistochemical study revealed positive results for AE1/AE3, CD56 and chromogranin A, with negative findings for synaptophysin, CK20, vimentin, CK8/18 and CD45. The patient was subsequently diagnosed with a poorly differentiated neuroendocrine carcinoma, small cell type. A bone marrow biopsy also revealed extensive involvement by the carcinoma.
Napaporn Nawarawong, Varayu Prachayakul, Siriraj GI Endoscopy Center, Division of Gastroenterology, Department of Internal Medicine, Siriraj Hospital, Mahidol University, Bangkok 10700, Thailand.
Napaporn
N
Nawarawong
Napaporn Nawarawong, Varayu Prachayakul, Siriraj GI Endoscopy Center, Division of Gastroenterology, Department of Internal Medicine, Siriraj Hospital, Mahidol University, Bangkok 10700, Thailand.
Tawatchai
T
Pongpruttipan
Napaporn Nawarawong, Varayu Prachayakul, Siriraj GI Endoscopy Center, Division of Gastroenterology, Department of Internal Medicine, Siriraj Hospital, Mahidol University, Bangkok 10700, Thailand.
Pitulak
P
Aswakul
Napaporn Nawarawong, Varayu Prachayakul, Siriraj GI Endoscopy Center, Division of Gastroenterology, Department of Internal Medicine, Siriraj Hospital, Mahidol University, Bangkok 10700, Thailand.
Varayu
V
Prachayakul
Bone marrow metastasis; Liver metastasis; Lymphoma; Mediastinal mass; Neuroendocrine tumor