Atypical Teratoid/Rhabdoid Tumor Involving Cerebrospinal Fluid A Case Report

Background Atypical teratoid/rhabdoid tumor (AT/RT) is a rare, aggressive tumor of the central nervous system. It is primarily seen in younger age-groups, and the cytomorphology has only been infrequently described. Case We present a case of AT/RT arising in the cervical spine of a 6-month-old boy. The cerebrospinal fluid (CSF) cytology and correlating findings are described. The CSF cytomorphologic findings of the AT/RT cells are most notably large cells, eccentrically placed pleomorphic nuclei, prominent nucleoli and, commonly, cytoplasmic inclusions, as well as a second population of smaller mononuclear cells with minimal cytoplasm. Conclusion The cervical spine is a rare site for AT/RT to arise. It is important for pathologists to recognize the cytomorphologic features of AT/RT in the CSF of patients with this tumor to help determine prognosis and disease progression. (Acta Cytol 2010;54:958-962)