TY - JOUR T1 - Permeability Estimates in Histopathology-Proved Treatment-Induced Necrosis Using Perfusion CT: Can These Add to Other Perfusion Parameters in Differentiating from Recurrent/Progressive Tumors? JF - American Journal of Neuroradiology JO - Am. J. Neuroradiol. SP - 658 LP - 663 DO - 10.3174/ajnr.A2378 VL - 32 IS - 4 AU - R. Jain AU - J. Narang AU - L. Schultz AU - L. Scarpace AU - S. Saksena AU - S. Brown AU - J.P. Rock AU - M. Rosenblum AU - J. Gutierrez AU - T. Mikkelsen Y1 - 2011/04/01 UR - http://www.ajnr.org/content/32/4/658.abstract N2 - BACKGROUND AND PURPOSE: Differentiating treatment effects from RPT is a common yet challenging task in a busy neuro-oncologic pratice. PS probably represents a different aspect of angiogenesis and vasculature and can provide additional physiologic information about recurrent/progressive enhancing lesions. The purpose of the study was to use PS measured by using PCT to differentiate TIN from RPT in patients with previously irradiated brain tumor who presented with a recurrent/progressive enhancing lesion. MATERIALS AND METHODS: Seventy-two patients underwent PCT for assessment of a recurrent/progressive enhancing lesion from January 2006 to November 2009. Thirty-eight patients who underwent surgery and histopathologic diagnosis were included in this analysis. Perfusion parameters such as PS, CBV, CBF, and MTT were obtained from the enhancing lesion as well as from the NAWM. RESULTS: Of 38 patients, 11 were diagnosed with pure TIN and 27 had RPT. Patients with TIN showed significantly lower mean PS values than those with RPT (1.8 ± 0.8 versus 3.6 ± 1.6 mL/100 g/min; P value = .001). The TIN group also showed lower rCBV (1.2 ± 0.3 versus 2.1 ± 0.7; P value < .001), lower rCBF (1.2 ± 0.5 versus 2.6 ± 1.7; P value = .004), and higher rMTT (1.4 ± 0.4 versus 1.0 ± 0.4; P value = .018) compared with the RPT group. CONCLUSIONS: PCT and particularly PS can be used in patients with previously treated brain tumors to differentiate TIN from RPT. PS estimates can help increase the accuracy of PCT in differentiating these 2 entities. BBBblood-brain barrierCBFcerebral blood flowCBVcerebral blood volumeEBRTexternal beam radiation therapyFSRTfractionated stereotactic radiation therapyGTRgross total resectionIMRTintensity-modulated radiation therapyIVintravenousMTTmean transit timeNAWMnormal-appearing white matterPCTperfusion CTPCVprocarbazine, chloroethyl-cyclohexyl-nitrosourea and vincristinePSpermeability surface area productPSRpercentage signal-intensity recoveryrCBFrelative CBFrCBVrelative CBVrMTTrelative MTTROCreceiver operating characteristic analysisrPSRrelative PSRRPTrecurrent/progressive tumorRTradiation therapySRSstereotactic radio-surgerySTRsubtotal resectionTINtreatment-induced necrosisTMZTemozolomideVEGFvascular endothelial growth factorWHOWorld Health Organization ER -