Cribriform neuroepithelial tumor (CRINET): a nonrhabdoid ventricular tumor with INI1 loss and relatively favorable prognosis

J Neuropathol Exp Neurol. 2009 Dec;68(12):1249-55. doi: 10.1097/NEN.0b013e3181c06a51.

Abstract

Atypical teratoid/rhabdoid tumors are malignant embryonal tumors characterized by the presence of rhabdoid cells, genetic alterations affecting the SMARCB1 gene (hSNF5/INI1), and a poor prognosis. Whether INI1 plays a role in the pathogenesis of other central nervous system tumors is uncertain. We report on cases of 2 young children with unusual intracranial nonrhabdoid neuroectodermal tumors within and around the third or fourth ventricle that are characterized by cribriform strands and trabeculae and well-defined epithelial membrane antigen-immunopositive surfaces and show INI1 protein loss. Histological and immunohistochemical features did not correspond to established tumor types, including atypical teratoid/rhabdoid tumors, medulloepithelioma, choroid plexus carcinoma, and ependymoma. Fluorescence in situ hybridization analyses failed to identify chromosomal alterations affecting the SMARCB1 locus, but sequencing revealed a homozygous 4-bp duplication in exon 4 (492duplCCTT) in one of the tumors. Both children responded well to conventional adjuvant therapy protocols and are alive and in complete remission longer than 5 years postoperatively. We suggest that cribriform neuroepithelial tumor (CRINET) is a nonrhabdoid ventricular tumor that shows loss of tumoral INI1 protein and has a relatively favorable prognosis.

Publication types

  • Case Reports
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Antineoplastic Combined Chemotherapy Protocols / therapeutic use
  • Brain Neoplasms / genetics*
  • Brain Neoplasms / pathology
  • Brain Neoplasms / therapy
  • Child, Preschool
  • Chromosomal Proteins, Non-Histone / genetics*
  • Combined Modality Therapy
  • DNA-Binding Proteins / genetics*
  • Female
  • Fourth Ventricle / pathology*
  • Humans
  • Immunohistochemistry
  • In Situ Hybridization, Fluorescence
  • Infant
  • Male
  • Neoplasms, Neuroepithelial / genetics*
  • Neoplasms, Neuroepithelial / pathology
  • Neoplasms, Neuroepithelial / therapy
  • Neurosurgical Procedures
  • Prognosis
  • Radiotherapy
  • SMARCB1 Protein
  • Third Ventricle / pathology*
  • Transcription Factors / genetics*

Substances

  • Chromosomal Proteins, Non-Histone
  • DNA-Binding Proteins
  • SMARCB1 Protein
  • SMARCB1 protein, human
  • Transcription Factors