Poorly differentiated chordoma with loss of SMARCB1/INI1 expression in pediatric patients: A report of two cases and review of the literature

Yoon Jin Cha, Chang Ki Hong, Dong Seok Kim, Seung Koo Lee, Hyeon Jin Park, Se Hoon Kim

Research output: Contribution to journalArticlepeer-review

26 Citations (Scopus)

Abstract

Identification of loss of SMARCB1/INI1 expression in poorly differentiated (PD) chordoma in pediatric patients suggests that PD chordoma is an entity molecularly distinct from conventional chordoma or atypical teratoid/rhabdoid tumor, which is also characterized by loss of SMARCB1/INI1 expression by inactivating mutation of the SMARCB1/INI gene. So far, around 20 cases of pediatric PD chordoma with loss of SMARCB1/INI1 expression have been reported. Here, we report two cases of pediatric PD chordoma with loss of SMARCB1/INI1 expression, which is very rare among the pediatric chordoma types. Both patients presented clival masses on preoperative MRI. Histologically, both tumors had nonclassic histologic features for conventional chordoma: sheets of large epithelioid to spindle cells with vesicular nuclei and prominent nucleoli. Both cases revealed nuclear expression of brachyury, loss of SMARCB1/INI1 expression and lack of embryonal, neuroectodermal, or epithelial component. One case showed heterozygous loss of EWSR1 gene by break-apart fluorescence in situ hybridization that reflected loss of SMARCB1/INI1 gene. Based on the clival location and histologic findings along with the loss of SMARCB1/INI1 expression and positivity for nuclear brachyury staining, the final pathologic diagnosis for both cases was PD chordoma.

Original languageEnglish
Pages (from-to)47-53
Number of pages7
JournalNeuropathology
Volume38
Issue number1
DOIs
Publication statusPublished - 2018 Feb

Bibliographical note

Publisher Copyright:
© 2017 Japanese Society of Neuropathology

All Science Journal Classification (ASJC) codes

  • Pathology and Forensic Medicine
  • Clinical Neurology

Fingerprint

Dive into the research topics of 'Poorly differentiated chordoma with loss of SMARCB1/INI1 expression in pediatric patients: A report of two cases and review of the literature'. Together they form a unique fingerprint.

Cite this