Atypical Teratoid/Rhabdoid Tumor of the Pineal Region in a Young Adult Male Patient: Case Report and Review of the Literature.

Atypical teratoid/rhabdoid tumor (AT/RT) represents a highly malignant and aggressive embryonal neoplasm of the central nervous system (CNS). Histologically it consists of rhabdoid cells with a varying combination of neuroectodermal, epithelial, and mesenchymal tissue. Histologic features and the poor clinical outcome indicate that this tumor corresponds to World Health Organization grade IV. AT/RT mainly occurs in children < 3 years of age and has only been rarely described in adults. It often arises from the posterior fossa of infants and has the tendency to spread through the subarachnoid space. In contrast to pediatric cases, most of the AT/RTs in adults are located in the cerebral hemispheres; infratentorial appearance or localization in the spinal cord is relatively uncommon. Likewise there are only a few reports of AT/RT in the pineal region. We present another interesting case of this tumor occurring in the pineal region of a 19-year-old man and discuss our case in the context of the current literature. The patient is alive 18 months since his initial diagnosis without any signs of tumor relapse.