Atypical Teratoid/ Rhabdoid Tumor
The Common Vein Copyright 2010
An atypical teratoid/ rhabdoid tumor is a highly malignant tumor of young children. It is seen in both posterior fossa and in the supratentorial compartment.
Pathologically these tumors are defined by the presence of rhabdoid cells with eosinophillic cytoplasm and elongated configurations which mimics those of a rhabdomyosarcoma. These are just one component of these tumors which have a mixed population of cell types, often also including mesenchymal and epithelial cell types. There is a high rate of mitosis. Intralesional necrosis and hemorrhage are common.
Clinically these patients present with nonspecific findings such as lethargy or failure to thrive.
On imaging these lesions are heterogeneous. They tend to be hyperattenuating on CT and demonstrate low density cystic components and areas of hemorrhage. On MRI, ATRT is a large heterogeneous mass. On T1 the signal is generally low. On T2, soft tissue areas are T2 isointense to hyperintense and cystic components are T2 hyperintense. There is generally heterogeneous enhancement. Seeding of the subarachnoid spaces is common at presentation.
Treatment for these lesions includes surgery with postoperative chemotherapy and possible radiation, however this diagnosis portends a poor prognosis with most patients dying within a year of diagnosis.