title: Diffusion and perfusion MRI to differentiate treatment-related changes including pseudoprogression from recurrent tumors in high-grade gliomas with histopathologic evidence.
abstract: OBJECTIVE
  Treatment-related changes and recurrent tumors often have overlapping features on conventional MR imaging. The purpose of this study was to assess the utility of DWI and DSC perfusion imaging alone and in combination to differentiate treatment-related effects and recurrent high-grade gliomas.
  
  
  METHODS
  We retrospectively identified 68 consecutive patients with high-grade gliomas treated by surgical resection followed by radiation therapy and temozolomide, who then developed increasing enhancing mass lesions indeterminate for treatment-related changes versus recurrent tumor. All lesions were diagnosed by histopathology at repeat surgical resection. ROI analysis was performed of the enhancing lesion on the ADC and DSC maps. Measurements made by a 2D ROI of the enhancing lesion on a single slice were recorded as ADCLesion and rCBVLesion, and measurements made by the most abnormal small fixed diameter ROI as ADCROI and rCBVROI. Statistical analysis was performed with Wilcoxon rank sum tests with P = .05.
  
  
  RESULTS
  Ten of the 68 patients (14.7%) had treatment-related changes, while 58 patients (85.3%) had recurrent tumor only (n = 19) or recurrent tumor mixed with treatment effect (n = 39). DWI analysis showed higher ADCLesion in treatment-related changes than in recurrent tumor (P = .003). DSC analysis revealed lower relative cerebral blood volume (rCBV)Lesion and rCBVROI in treatment-related changes (P = .003 and P = .011, respectively). Subanalysis of patients with suspected pseudoprogression also revealed higher ADCLesion (P = .001) and lower rCBVLesion (P = .028) and rCBVROI (P = .032) in treatment-related changes. Applying a combined ADCLesion and rCBVLesion model did not outperform either the ADC or rCBV metric alone.
  
  
  CONCLUSIONS
  Treatment-related changes showed higher diffusion and lower perfusion than recurrent tumor. Similar correlations were found for patients with suspected pseudoprogression.
authors.affiliation: From the Departments of Radiology (A.J.P., R.J.Y.).
authors.forename: A J
authors.initials: AJ
authors.lastname: Prager
authors.affiliation: Neurology (N.M., A.O.).
authors.forename: N
authors.initials: N
authors.lastname: Martinez
authors.affiliation: Radiation Oncology (K.B.) the Brain Tumor Center (K.B., A.O., R.J.Y.), Memorial Sloan Kettering Cancer Center, New York, New York.
authors.forename: K
authors.initials: K
authors.lastname: Beal
authors.affiliation: Neurology (N.M., A.O.) the Brain Tumor Center (K.B., A.O., R.J.Y.), Memorial Sloan Kettering Cancer Center, New York, New York.
authors.forename: A
authors.initials: A
authors.lastname: Omuro
authors.affiliation: Epidemiology and Biostatistics (Z.Z.).
authors.forename: Z
authors.initials: Z
authors.lastname: Zhang
authors.affiliation: From the Departments of Radiology (A.J.P., R.J.Y.) the Brain Tumor Center (K.B., A.O., R.J.Y.), Memorial Sloan Kettering Cancer Center, New York, New York. youngr@mskcc.org.
authors.forename: R J
authors.initials: RJ
authors.lastname: Young
mesh_terms: D000368:Aged; D000970:Antineoplastic Agents / Q000009:adverse effects; D001927:Brain Diseases / Q000175:diagnosis* / Q000209:etiology; D001932:Brain Neoplasms / Q000473:pathology*; D003606:Dacarbazine / Q000009:adverse effects / Q000031:analogs & derivatives; D018450:Disease Progression; D005260:Female; D005910:Glioma / Q000473:pathology*; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D060787:Neoplasm Grading; D009364:Neoplasm Recurrence, Local / Q000473:pathology*; D019635:Neurosurgical Procedures / Q000009:adverse effects; D011878:Radiotherapy / Q000009:adverse effects; D012189:Retrospective Studies; D000077204:Temozolomide
chemical_list: D000970:Antineoplastic Agents; D003606:Dacarbazine; D000077204:Temozolomide