RESUMO
Resumen El tumor de Askin es una rara neoplasia de la pared torácica que pertenece al grupo de tumores neuroectodérmicos primitivos que incluyen desde el sarcoma de Ewing hasta el neuroepitelioma. Su principal característica es el dolor. Los tumores neuroectodérmicos primitivos (PNET) derivan de células pluripotenciales neuroectodérmicas de la cresta neural y pertenecen al grupo de tumores de células pequeñas redondas y azules que se caracterizan por un comportamiento agresivo, con manifestaciones clínicas diversas que dependen de su localización anatómica. La localización más común es la toracopulmonar, seguida por el área pélvica. Las metástasis normalmente afectan a los pulmones, huesos, hígado y cerebro. Su diagnóstico se basa en estudios imagenológicos y se confirma con el estudio de histopatología en biopsia o en la resección quirúrgica.
Abstract The Askin's tumor is a rare neoplasm of the chest wall that belongs to the group of primitive neuroectodermal tumors (PNETs), which are derivatives from neuroectodermal pluripotent neural crest cells. The range of this type of tumors covers from Ewing's sarcoma to the neuroepithelioma and they belong to the group of small round blue cells tumors which are characterized for having an aggressive behavior with diverse clinical manifestations depending on their anatomical location. The most common location for the Askin's tumor is the thoracopulmonary area followed by the pelvic area and in the case of metastases the lungs, bones, liver and brain are the most affected parts. In order to identify this disease, the diagnosis of this type of tumor consists on image studies and the confirmation is made through a hispathology biopsy or surgical resection.
RESUMO
OBJECTIVE: To explore the imaging features of adrenal primitive neuroectodermal tumors (PNETs). MATERIALS AND METHODS: This retrospective study included seven patients with surgically and pathologically confirmed adrenal PNETs. Among them, six underwent computed tomography (CT) scans, and one underwent magnetic resonance imaging. The imaging findings, including size, shape, margin, hemorrhage, calcification, cystic degeneration, regional lymph nodes involvement, tumor thrombus formation and enhancement pattern, were retrospectively analyzed. RESULTS: Among the seven adrenal PNET patients, six were male, and one was female. The median age was 26 years (range 2-56 years). The disease generally presented with either insidious symptoms (n = 4) or non-specific symptoms, including right flank pain (n = 1) and left upper abdominal discomfort (n = 2). On the pre-enhanced CT images, the tumor usually appeared as a well-defined, rounded or oval, heterogeneous mass without calcification. Certain tissue characteristics, such as cystic degeneration (n = 5), capsule (n = 4) and hemorrhage (n = 2), were observed. Regional lymph node involvement was observed in three cases, and renal vein thrombus was observed in one case. All cases showed mild heterogeneous enhancement of the tumor on the enhanced CT images. CONCLUSION: An adrenal PNET commonly presents as a relatively large, well-defined, heterogeneous mass with cystic degeneration, necrosis and a characteristic mild contrast-enhancement pattern on multiphase enhanced images. PNET should be considered when the diagnosis of common tumors is not favored by signs on images. CLINICAL TRIAL REGISTRATION STATEMENT: This study was approved by the medical ethics committee of Xiangya Hospital, Central South University. The approval number is 201512538.