CIC-rearranged Sarcomas: A Study of 20 Cases and Comparisons With Ewing Sarcomas

Am J Surg Pathol. 2016 Mar;40(3):313-23. doi: 10.1097/PAS.0000000000000570.

Abstract

The CIC gene rearrangement exists in a subset of small round cell sarcomas. As the nosologic relationship of these sarcomas to Ewing sarcomas remains undetermined, we examined 20 CIC-rearranged sarcomas to compare their clinicopathologic features with those of Ewing sarcomas. The CIC-rearranged sarcomas were from a group of 14 men and 6 women with a median age of 24.5 years. The primary tumor sites included the limbs, trunk wall, internal trunk, lung, cerebrum, and pharynx. A comparison of the demographic and clinical characteristics of the 20 patients with CIC-rearranged sarcomas with those of the 53 near-consecutive patients with EWSR1-rarranged Ewing sarcomas showed that there were no differences with respect to their ages and sexes. Although none of the CIC-rearranged sarcomas arose in the bone, 40% of the Ewing sarcomas primarily affected the skeleton. The overall survival of patients with Ewing sarcomas was significantly better than that for patients with CIC-rearranged sarcomas. A histologic comparison of the CIC-rearranged sarcomas with 20 EWSR1-rearranged Ewing sarcomas showed significantly higher degrees of lobulation, nuclear pleomorphism, the prominence of the nucleoli, spindle cell elements, and myxoid changes in the CIC-rearranged sarcomas. Distinguishing immunohistochemical features included heterogenous CD99 reactivity, nuclear WT1 expression, and calretinin expression in the CIC-rearranged sarcomas and NKX2.2 expression in the Ewing sarcomas. CIC-rearranged sarcomas are distinct from Ewing sarcomas clinically, morphologically, and immunohistochemically, and they should be considered a separate entity rather than being grouped within the same family of tumors.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Adult
  • Aged
  • Biomarkers, Tumor / genetics*
  • Bone Neoplasms / chemistry
  • Bone Neoplasms / genetics*
  • Bone Neoplasms / mortality
  • Bone Neoplasms / pathology
  • Bone Neoplasms / therapy
  • Calmodulin-Binding Proteins / genetics*
  • Diagnosis, Differential
  • Female
  • Gene Rearrangement*
  • Homeobox Protein Nkx-2.2
  • Homeodomain Proteins
  • Humans
  • Immunohistochemistry
  • In Situ Hybridization, Fluorescence
  • Kaplan-Meier Estimate
  • Male
  • Middle Aged
  • Nuclear Proteins
  • Predictive Value of Tests
  • Prognosis
  • RNA-Binding Protein EWS
  • RNA-Binding Proteins / genetics*
  • Repressor Proteins / genetics*
  • Sarcoma / chemistry
  • Sarcoma / genetics*
  • Sarcoma / mortality
  • Sarcoma / pathology
  • Sarcoma / therapy
  • Sarcoma, Ewing / chemistry
  • Sarcoma, Ewing / genetics*
  • Sarcoma, Ewing / mortality
  • Sarcoma, Ewing / pathology
  • Sarcoma, Ewing / therapy
  • Transcription Factors
  • Young Adult

Substances

  • Biomarkers, Tumor
  • CIC protein, human
  • Calmodulin-Binding Proteins
  • EWSR1 protein, human
  • Homeobox Protein Nkx-2.2
  • Homeodomain Proteins
  • NKX2-2 protein, human
  • Nuclear Proteins
  • RNA-Binding Protein EWS
  • RNA-Binding Proteins
  • Repressor Proteins
  • Transcription Factors