Atypical teratoid/rhabdoid tumors: imaging findings of two cases and review of the literature.

Atypical teratoid/rhabdoid tumor (AT/RT) is a malignant embryonal central nervous system (CNS) tumor, manifesting in children, and composed of rhabdoid cells, with or without fields resembling a classical primitive neuroectodermal tumor (PNET), epithelial tissue and neoplastic mesenchyme. Around 200 cases of CNS AT/RT have been documented in the literature. Although the clinical and pathological findings have been defined in large series previously, and AT/RT has become increasingly recognized, awareness of typical AT/RT is important in making the correct diagnosis of this uncommon but probably underdiagnosed entity. Neuroradiologists rarely mention AT/RT in their differential diagnosis and this paper presents two additional cases in which clinical and pathological findings are combined with neuroradiological presentation.