Atypical teratoid/rhabdoid tumor of lumbar spine in a toddler child

Abstract

Background: Atypical teratoid/rhabdoid tumor (AT/RT) is a rare pediatric central nervous system malignancy with poor outcome. AT/RT is infrequently located in the spinal cord.

Clinical presentation: A 16-month-old boy presented with progressive urinary retention and weakness of the lower extremities. Magnetic resonance imaging of the spine revealed an intradural extramedullary mass occupying the spinal canal at the level of T10-L3. The tumor was successfully resected by using neuroendoscopy. Histopathology demonstrated rhabdoid cells with eccentric nuclei and eosinophilic cytoplasmic hyaline inclusions. Immunohistologically, the tumor cells showed positive for epithelial membrane antigen, vimentin and neuron-specific enolase, and negative for integrase interactor 1. After surgery, the patient showed significant improvement in sitting and other neurological signs but presenting with flaccid neurogenic bladder. Intrathecal chemotherapy under European Rhabdoid Registry (EU-RHAB) protocol with Doxorubicin, Carboplatin, Etoposide, Ifosfamide, Vincristine, Cyclophosphamide and Actinomycin-D was given. However, recurrent intradural extramedullary tumor at the level of T11-L2 developed in 3 months.

Conclusion: We report a young Asian case of AT/RT in thoracolumbar spine with recurrent tumor shortly after complete surgical resection of the tumor.

Keywords: CNS cancer.

Figure 1

Magnetic resonance imaging of the spine. (a) T2-weighted sagittal image shows an intradural extramedullary mass occupying the spinal canal at the level of T11-L3. (b) Gadolinium-enhanced T1-weighted, fat suppression sagittal image demonstrates heterogeneous enhancement of this mass. (c) Three months post operation, gadolinium-enhanced T1-weighted, fat suppression sagittal image demonstrates recurrent intradural extramedullary mass at the level of T11-L2 (arrows: tumor).

Figure 2

(a) Surgical findings show tumor abutting the caudal equina. Complete resection of the tumor was performed with partial resection of the cauda equina (arrows: tumor). (b) Squash preparation showed large, pleomorphic, plasmacytoid and polygonal cells with eccentric nuclei and dense amphophilic cytoplasm (hematoxylin and eosin; original magnification x400). (c) Histopathologically, there are predominant cells with rhabdoid features including eccentric nuclei, and eosinophilic cytoplasmic hyaline inclusions. (hematoxylin and eosin; original magnification x400). (d) Loss of INI-1 immunoreactivity was seen, characteristic of atypical teratoid rhabdoid tumors. (INI-1; original magnification x400).