title: Is there pseudoprogression in secondary glioblastomas?
abstract: OBJECTIVE
  Pseudoprogression (PP) during adjuvant treatment of glioblastoma (GBM) is frequent and is a clinically and radiologically challenging problem. While there are several reports of the frequency of PP in GBM cohorts including mainly patients with primary GBM, there are few data on the incidence of PP in patients with secondary glioblastomas (sGBM). Therefore, the goal of this study was to evaluate the frequency of PP in sGBM.
  
  
  METHODS
  We retrospectively evaluated the incidence of PP in adult patients with sGBM treated with chemoradiation therapy (CRTx) using temozolomide (TMZ) and sought to assess if there was an association between PP and MGMT promoter methylation status, IDH mutations status, or 1p/19q codeletion. The definition of PP according to the Response Assessment in Neuro-Oncology Working Group was used.
  
  
  RESULTS
  None of the evaluable 15 sGBM patients in our series demonstrated a PP. Of the 9 sGBM patients who received concomitant CRTx with TMZ, 6 patients had the methylated MGMT promoter, and 6 patients had IDH mutations. There also was no PP identified in sGBM patients who received sequential CRTx, irrespective of MGMT or IDH status. The median time of follow-up was 3.4 years after diagnosis of an sGBM, and the median overall survival was 18.2 months (range, 14.3-45.2 months). Three of 15 patients had previously received radiation therapy for their World Health Organization low-grade 2 glioma, while none of them had received chemotherapy at that stage.
  
  
  CONCLUSIONS
  Based on this small series of sGBM patients treated with CRTx (concomitantly or sequentially) the frequency of PP appears to be very low in sGBM, even in those patients with methylated MGMT promoter or IDH mutations. Our results highlight the differences between primary glioblastomas and sGBM in particular as they relate to PP.
authors.affiliation: Department of Neurosurgery, University Hospital Carl Gustav Carus, Technical University of Dresden, Dresden, Germany. Electronic address: Tareq.Juratli@uniklinikum-dresden.de.
authors.forename: Tareq A
authors.initials: TA
authors.lastname: Juratli
authors.forename: Kay
authors.initials: K
authors.lastname: Engellandt
authors.forename: Tim
authors.initials: T
authors.lastname: Lautenschlaeger
authors.forename: Kathrin D
authors.initials: KD
authors.lastname: Geiger
authors.forename: Rüdiger
authors.initials: R
authors.lastname: von Kummer
authors.forename: Jana
authors.initials: J
authors.lastname: Cerhova
authors.forename: Arnab
authors.initials: A
authors.lastname: Chakravarti
authors.forename: Dietmar
authors.initials: D
authors.lastname: Krex
authors.forename: Gabriele
authors.initials: G
authors.lastname: Schackert
mesh_terms: D000328:Adult; D000368:Aged; D018906:Antineoplastic Agents, Alkylating / Q000627:therapeutic use; D001932:Brain Neoplasms / Q000235:genetics / Q000378:metabolism / Q000401:mortality / Q000473:pathology* / Q000628:therapy; D059186:Chemoradiotherapy, Adjuvant / Q000379:methods; D002900:Chromosomes, Human, 1-3 / Q000235:genetics; D019175:DNA Methylation; D015254:DNA Modification Methylases / Q000235:genetics / Q000378:metabolism; D045643:DNA Repair Enzymes / Q000235:genetics / Q000378:metabolism; D003606:Dacarbazine / Q000031:analogs & derivatives / Q000627:therapeutic use; D018450:Disease Progression; D018572:Disease-Free Survival; D005260:Female; D017353:Gene Deletion; D005909:Glioblastoma / Q000235:genetics / Q000378:metabolism / Q000401:mortality / Q000473:pathology* / Q000628:therapy; D006801:Humans; D007521:Isocitrate Dehydrogenase / Q000235:genetics; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009154:Mutation / Q000235:genetics; D012189:Retrospective Studies; D000077204:Temozolomide; D025521:Tumor Suppressor Proteins / Q000235:genetics / Q000378:metabolism
chemical_list: D018906:Antineoplastic Agents, Alkylating; D025521:Tumor Suppressor Proteins; D003606:Dacarbazine; D007521:Isocitrate Dehydrogenase; D015254:DNA Modification Methylases; C515491:MGMT protein, human; D045643:DNA Repair Enzymes; D000077204:Temozolomide