Atypical Teratoid

Definition

AT/RT is a rare and aggressive brain and spinal cord tumor that primarily affects young children, typically under the age of 3. It originates in the central nervous system and is known for its fast growth.

Characteristics

AT/RT tumors are often located in the cerebellum or brainstem but can appear anywhere in the CNS. They are defined by the loss of a specific gene (SMARCB1), which helps regulate cell growth. Symptoms depend on the tumor’s location and may include headaches, nausea, trouble with balance, or behavioral changes.

Diagnosis and Prognosis

Diagnosis involves MRI scans, biopsy, and genetic testing to confirm SMARCB1 loss. Because of its rapid progression and typical occurrence in very young children, the prognosis is generally poor, though outcomes are improving with newer treatment approaches.

Treatment

Treatment usually includes surgery to remove as much of the tumor as possible, followed by intensive chemotherapy and sometimes radiation. Targeted therapies and clinical trials may also be considered due to the tumor’s genetic profile and resistance to standard treatments.

Last Revised: 12 May , 2025