TY - JOUR

T1 - Prognostic value of 18F-FET PET imaging in re-irradiation of high-grade glioma

T2 - Results of a phase I clinical trial

AU - Moller, Soren

AU - Law, Ian

AU - Munck af Rosenschöld, Per

AU - Costa, Junia

AU - Poulsen, Hans Skovgaard

AU - Engelholm, Svend Aage

AU - Engelholm, Silke

N1 - Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

PY - 2016/10

Y1 - 2016/10

N2 - BACKGROUND AND PURPOSE: Positron emission tomography (PET) provides quantitative metabolic information and potential biomarkers of treatment outcome. We aimed to determine the prognostic value of early (18)F-fluoroethyl-tyrosine ((18)F-FET) PET scans acquired during re-irradiation for recurrent high-grade glioma (HGG).MATERIAL AND METHODS: A phase I clinical trial of re-irradiation of HGG was carried out. MRI and (18)F-FET PET were used for target delineation and follow-up. Images were acquired at baseline, during radiotherapy and 4weeks post-treatment and compared by measuring the metabolically active biological tumor volume (BTV) and maximal activity (Tmax/B). Correlations with outcomes were assessed by multivariate Cox regression analysis.RESULTS: Thirty-one patients were included and all patients have died. The median overall survival was 7.0 mos. Both baseline BTV and baseline MRI volume (necrotic/cystic cavities subtracted) were prognostic for overall survival (OS) in multivariate analysis (HR=1.3 p<0.01 and HR=1.3 p<0.01, respectively). Early changes in BTV and Tmax/B were observed but they carried no independent prognostic information.CONCLUSIONS: Baseline biological tumor volume (BTV) defined by (18)F-FET PET was prognostic for OS in multivariate analysis, as was MRI volume (necrotic/cystic cavities subtracted). Tumor volume may aid in identifying patients whose life expectancy is too short to warrant re-irradiation.

AB - BACKGROUND AND PURPOSE: Positron emission tomography (PET) provides quantitative metabolic information and potential biomarkers of treatment outcome. We aimed to determine the prognostic value of early (18)F-fluoroethyl-tyrosine ((18)F-FET) PET scans acquired during re-irradiation for recurrent high-grade glioma (HGG).MATERIAL AND METHODS: A phase I clinical trial of re-irradiation of HGG was carried out. MRI and (18)F-FET PET were used for target delineation and follow-up. Images were acquired at baseline, during radiotherapy and 4weeks post-treatment and compared by measuring the metabolically active biological tumor volume (BTV) and maximal activity (Tmax/B). Correlations with outcomes were assessed by multivariate Cox regression analysis.RESULTS: Thirty-one patients were included and all patients have died. The median overall survival was 7.0 mos. Both baseline BTV and baseline MRI volume (necrotic/cystic cavities subtracted) were prognostic for overall survival (OS) in multivariate analysis (HR=1.3 p<0.01 and HR=1.3 p<0.01, respectively). Early changes in BTV and Tmax/B were observed but they carried no independent prognostic information.CONCLUSIONS: Baseline biological tumor volume (BTV) defined by (18)F-FET PET was prognostic for OS in multivariate analysis, as was MRI volume (necrotic/cystic cavities subtracted). Tumor volume may aid in identifying patients whose life expectancy is too short to warrant re-irradiation.

KW - Journal Article

U2 - 10.1016/j.radonc.2016.08.014

DO - 10.1016/j.radonc.2016.08.014

M3 - Journal article

C2 - 27622554

VL - 121

SP - 132

EP - 137

JO - Radiotherapy & Oncology

JF - Radiotherapy & Oncology

SN - 0167-8140

IS - 1

ER -