Related Experiment Video
Updated: Mar 16, 2026
In Vivo Model for Testing Effect of Hypoxia on Tumor Metastasis
Published on: December 9, 2016
Maturation toward neuronal tissue in a Ewing sarcoma of bone after chemotherapy
Maria Carolina Wilhelmina Salet1, Rob Vogels2, Paul Brons3
1Department of Pathology, Radboud University Medical Center, P.O. Box 9101, Nijmegen, 6500 HB, The Netherlands. Myrthe.Salet@radboudumc.nl.
Background:
Ewing sarcoma is the second most common bone tumor, occurring mainly in children and young adults. It shows a typical primitive, small round cell morphology and a characteristic fusion oncogene involving EWSR1 and members of the ETS family in most of the cases. Neuronal maturation after chemotherapy is a rare phenomenon and we herein describe such an exceptional case.
Case Presentation:
An 8-year old boy was diagnosed with a Ewing sarcoma in the left femur. On biopsy the morphology was typical and there was an EWSR1-FLI1 gene fusion. He underwent neo-adjuvant chemotherapy and resection of the tumor. On microscopic evaluation, part of the tumor showed ganglioneuroblastoma-like differentiation with expression of neuronal markers. The continued presence of EWSR1 rearrangement in both the blue round cell component and the ganglioneuroblastoma-like component was shown by FISH analysis.
Conclusions:
In conclusion, this case describes the possibility of a Ewing sarcoma to differentiate into a ganglioneuroblastoma-like lesion after neo-adjuvant chemotherapy treatment; the prognostic value of this phenomenon remains questionable.
