Late post-treatment radiographic changes 3 years following chemoradiation for glioma: the importance of histopathology

Joao R Galante; Fausto Rodriguez; Stuart A Grossman; Roy E Strowd

doi:10.2217/cns-2016-0040

Late post-treatment radiographic changes 3 years following chemoradiation for glioma: the importance of histopathology

CNS Oncol. 2017 Jul 18;6(3):195-201. doi: 10.2217/cns-2016-0040. Online ahead of print.

Authors

Joao R Galante^{1

2}, Fausto Rodriguez³, Stuart A Grossman⁴, Roy E Strowd⁵

Affiliations

¹ Poznan University of Medical Sciences, 41 Jackowskiego Street, 60-512 Poznan, Poland.
² Department of Oncology, Johns Hopkins University School of Medicine, 733 North Broadway Street, Baltimore, MD 21205, USA.
³ Department of Pathology, The Sidney Kimmel Comprehensive Cancer Center at Johns Hopkins, David H. Koch Cancer Research Bldg II, 1550 Orleans Street, Room 1M16, Baltimore, MD 21287, USA.
⁴ Medical Oncology, The Sidney Kimmel Comprehensive Cancer Center at Johns Hopkins, David H. Koch Cancer Research Bldg II, 1550 Orleans Street, Room 1M16, Baltimore, MD 21287, USA.
⁵ Department of Neurology and Internal Medicine, Section on Hematology and Oncology, Wake Forest School of Medicine, Winston Salem, NC 27157, USA.

Abstract

Treatment-related changes can mimic brain tumor progression both clinically and radiographically. Distinguishing these two entities represents a major challenge in neuro-oncology. No single imaging modality is capable of reliably achieving such distinction. While histopathology remains the gold standard, definitive pathological criteria are also lacking which can further complicate such cases. We report a patient with high-grade glioma who, after initially presenting with histopathologically confirmed pseudoprogression 10 months following treatment, re-presented 3 years following concurrent chemoradiation with clinical and radiographic changes that were most consistent with progressive disease but for which histopathology revealed treatment effects without active glioma. This case highlights the potential late onset of treatment-related changes and underscores the importance of histopathologic assessment even years following initial therapy.

Keywords: DWI; MRI; MRS; PET; brain cancer; diagnostic challenge; high-grade glioma; neuro-oncology; post-treatment changes; pseudoprogression; radiation necrosis; radiation therapy.