RESUMEN
A 59-year-old woman with a history of fibrosing mediastinitis secondary to histoplasmosis diagnosed on mediastinoscopy presented with dyspnea. A ventilation-perfusion scan demonstrated decreased perfusion to the entire right lung. In addition, the perfusion images demonstrated focal abnormal activity in part of the liver. On computed tomography of the chest, there was significant soft tissue opacification in the mediastinum occluding the right pulmonary artery, with passage of the injected contrast via collateral vessels to the liver. The main collateral pathway was via the right internal thoracic vein and the umbilical vein. Pulmonary angiography confirmed complete occlusion of the right pulmonary artery.
Asunto(s)
Histoplasmosis/complicaciones , Histoplasmosis/diagnóstico por imagen , Hipertensión Pulmonar/diagnóstico por imagen , Mediastinitis/diagnóstico por imagen , Mediastinitis/etiología , Síndrome de la Vena Cava Superior/diagnóstico por imagen , Síndrome de la Vena Cava Superior/etiología , Femenino , Fibrosis/diagnóstico por imagen , Fibrosis/patología , Humanos , Hipertensión Pulmonar/etiología , Hígado/diagnóstico por imagen , Persona de Mediana Edad , Derivación Portosistémica Quirúrgica/efectos adversos , Arteria Pulmonar/diagnóstico por imagen , Cintigrafía , Síndrome de la Vena Cava Superior/cirugíaAsunto(s)
Fluorodesoxiglucosa F18 , Neoplasias Pulmonares/diagnóstico por imagen , Neoplasias Pulmonares/secundario , Mesotelioma/diagnóstico por imagen , Mesotelioma/secundario , Tomografía de Emisión de Positrones/métodos , Radiofármacos , Diagnóstico Diferencial , Fluorodesoxiglucosa F18/farmacocinética , Humanos , Neoplasias Pulmonares/patología , Metástasis Linfática , Masculino , Mesotelioma/patología , Persona de Mediana Edad , Estadificación de Neoplasias , Radiofármacos/farmacocinéticaRESUMEN
Merkel cell carcinoma is a rare type of neuroendocrine tumor of the skin with approximately 470 documented new cases annually in the United States. These tumors have high metastatic and recurrence rates, making them aggressive and difficult to treat. Diagnostic workup usually includes computed tomography, magnetic resonance imaging, and scintigraphy methods such as octreotide scans. More recently, positron emission tomographic scanning has been used to evaluate Merkel cell carcinomas. A case of Merkel cell carcinoma, in which positron emission tomography imaging with fluorodeoxyglucose played an important role in staging, re-staging, and identifying previously unknown distant metastatic disease, is presented in this article.