ATYPICAL TERATOID/RHABDOID TUMOR

AT/RT; Central Nervous System AT/RT; CNS AT/RT; Malignant AT/RT; Childhood Atypical Teratoid / Rhabdoid Tumor; Childhood AT/RT

Atypical Teratoid/ Rhabdoid Tumor (AT/RT) is a rare central nervous system tumor of the brain and spinal cord, which may also originate in other organs and tissues. It usually occurs in children younger than three years of age, although it can occur in older children and adults. About half of these tumors form in the cerebellum or brain stem.

Approximately 90% of AT/RTs are caused by genetic mutations in the INI1 gene.

Diagnostic testing: AT/RT is diagnosed using a combination of:

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  Clinical history;

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  Physical examination;

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  Imaging (CT or MRI scans, ultrasound, bone scan);

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  Biopsy results;

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  Laboratory tests including lumbar puncture, bone marrow biopsy and aspiration; and

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  INI1 gene testing for mutations.

Physical findings and Symptoms: Children with AT/RT may present with:

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  Complaints of morning headache or headache that goes away after vomiting;

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  Unusual sleepiness or change in activity level;

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  Loss of balance, lack of coordination, or trouble walking; and

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  Increased head size in infants.

ICD-9: 191.00

AT/RTs usually occur in children younger than three years of age, although it can occur in older children and adults. Symptoms of AT/RTs may develop quickly and progress over a period of days or weeks with symptoms varying depending on the age of the child and the location of the tumor. Children presenting with AT/RT before the age of 3 years have a poor prognosis. The prognosis is also based on residual tumor remaining after surgery, and whether the cancer has spread (metastasized) to other parts of the central nervous system or rest of the body such as kidney.

There is no standard staging system for central nervous system atypical teratoid/ rhabdoid tumor. This tumor is classified as newly diagnosed or recurrent. Treatment depends on the age of the child and extent of the cancer, and may include chemotherapy, radiation therapy, or high-dose chemotherapy with stem cell transplant. Long-term survival is possible in adults receiving multimodal therapy.

Suggested MER for Evaluation:

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  Clinical history and examination that describes the diagnostic features of the impairment;

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  Pathology report;

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  Operative reports;

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  MRI/ CT scans, bone scans, ultrasound; and

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  Results of bone marrow biopsy or lumbar puncture (spinal tap).

Suggested Listings for Evaluation:

REMARKS

Listing level severity must be documented. Evaluate under 13.13 in adults if the tumor originates in the central nervous system. Evaluate under the appropriate adult listing when AT/RT originates in locations besides the central nervous system, such as in the neck (13.02 D), mediastinum (13.15 B 1), liver (13.19), and kidney (13.21 B).

Listing level severity must be documented.Evaluate under 113.03 when the tumor originates in locations besides the central nervous system.