Atypical teratoid/rhabdoid tumor of the brain – A case with three secondary implants

Abstract

Atypical teratoid/rhabdoid (AT/RT) of the brain is a rare malignant pediatric neoplasm that usually affects children around age two. This report is about a male patient, six months of age, who presented with seizures and decreased level of consciousness, progressing to numbness, oculomotor nerve palsy and tetra-spasticity. CT scan showed left cerebellopontine angle tumor. Magnetic resonance imaging (MRI) showed a solid lesion, hypointense on T1W and heterogeneous hyperintense on T2W, enhanced after contrast infusion, accompanied by three solid lesions, rounded and irregular in the left cerebellar hemisphere, occipito-parietal transition and right occipital lobe with no evidence of leptomeningeal spread, forming secondary implants. We conducted a biopsy, which confirmed AT/ RT. Chemotherapic treatment was ineffective and the patient passed away quickly. In the literature review we found about 300 cases reported, as it is, therefore, extremely rare tumor with a mean age at diagnosis of 29 months. It can affect any area of the central nervous system, mainly infratentorial, being its main differential diagnosis medulloblastomas. The findings of secondary implantation without leptomeningeal spread seen in this patient are described in only one other case in literature. The clinical features usually are neurological deficits, seizures and coma. Its genesis stems from mutations in the gene hSNF5/INI1 on chromosome 22. Neuroimaging studies don’t reveal radiological pattern suggesting AT/RT and the diagnosis is possible only through a biopsy with immunohistochemical analysis. The available treatments are ineffective, and death is the outcome, with 84% in six months.

Keywords

• rhabdoid tumor
• brain neoplasms