Atypical teratoid/rhabdoid tumors

Alyssa Reddy MD (Dr. Reddy of Children's Hospital of Alabama in Birmingham has no relevant financial relationships to disclose.)
Roger J Packer MD, editor. (Dr. Packer of George Washington University and Senior VP of Neuroscience at Children's National Medical Center has no relevant financial relationships to disclose.)
Originally released April 29, 2003; last updated June 22, 2015; expires June 22, 2018

This article includes discussion of atypical teratoid/rhabdoid tumors, AT/RT, and malignant rhabdoid tumor of the brain or central nervous system. The foregoing terms may include synonyms, similar disorders, variations in usage, and abbreviations.

Overview

Atypical teratoid/rhabdoid tumor is a highly malignant brain tumor that was not recognized until the late 1980s. It typically affects young children and is often rapidly fatal. The tumor has also been reported in older children and adults, and the overall incidence has probably been underestimated. Most published data have been based on small series and are retrospective. One prospective study demonstrated improved survival with intensive multimodal therapy. Atypical teratoid/rhabdoid tumor is the first pediatric brain tumor for which a candidate tumor suppressor gene has been identified. Gene expression profiling analysis suggests that there are distinct molecular subtypes of atypical teratoid/rhabdoid tumor. The Children's Oncology Group completed accrual to the first cooperative group treatment trial for this disease; the trial combines high-dose chemotherapy and focused radiation.

Key points

 

• Atypical teratoid/rhabdoid tumor is often fatal, but subsets of patients are long-term survivors after aggressive multimodal therapy.

 

• A somatic mutation of the SMARCB1 gene can be found in nearly all atypical teratoid/rhabdoid tumors, and an immunohistochemical stain for the gene product can help pathologists readily identify the tumor.

 

• Patients with germline mutations for the SMARCB1 gene often have disseminated or synchronous tumors, and their disease behaves more aggressively.

 

• Emerging gene expression data suggests that there are molecular subtypes that likely correlate with outcome.

 

• Targeted biological therapies that can block cellular proliferation in atypical teratoid/rhabdoid tumor are greatly needed.

Historical note and terminology

Atypical teratoid/rhabdoid tumor of the central nervous system is a rare, highly malignant disease that occurs primarily in young children. It was first identified by Rorke and colleagues as a unique tumor type in 1987 (Lefkowity et al 1987). Prior to that time, patients with atypical teratoid/rhabdoid tumor were often misdiagnosed as having medulloblastoma or other embryonal tumor. This is understandable because approximately two thirds have components that resemble medulloblastoma or embryonal tumor (Rorke et al 1996). In addition to rhabdoid cells, atypical teratoid/rhabdoid tumors often contain malignant epithelial and mesenchymal components that further distinguish them from medulloblastoma and primitive neuroectodermal tumor. Because it histologically resembles the rhabdoid tumor of the kidney, atypical teratoid/rhabdoid tumor was sometimes referred to as malignant rhabdoid tumor of the brain or central nervous system (Fisher et al 1996) before it was recognized as a distinct entity. The World Health Organization began classifying atypical teratoid/rhabdoid tumor an embryonal grade IV neoplasm in 1993 (Kleihues et al 2002). The disease is often simply referred to as AT/RT.

The content you are trying to view is available only to logged in, current MedLink Neurology subscribers.

If you are a subscriber, please log in.

If you are a former subscriber or have registered before, please log in first and then click select a Service Plan or contact Subscriber Services. Site license users, click the Site License Acces link on the Homepage at an authorized computer.

If you have never registered before, click Learn More about MedLink Neurology  or view available Service Plans.