Evaluation of combined bevacizumab plus irinotecan therapy in brain tumors using magnetic resonance imaging measures of relative cerebral blood volume.
Frequently, bevacizumab is combined with chemotherapeutics such as irinotecan, motivated by studies showing improved clinical outcomes compared with historical controls. However, no systematic studies have been performed to determine if and how these drugs should be combined for optimal therapeutic response. The purpose of this study was to characterize the temporal combinations of bevacizumab and irinotecan by measuring the contrast-agent enhanced tumor volumes and relative cerebral blood volume using dynamic susceptibility contrast imaging. The studies, performed in the U87 brain tumor model, show a vascular normalization window with bevacizumab monotherapy and are consistent with clinical indications of no additional benefit in the addition of irinotecan to bevacizumab therapy.
Translational Brain Tumor Research Program, Department of Neurosurgery, Medical College of Wisconsin, Milwaukee, Wisconsin 53226, USA. kpechman@mcw.edu
Kimberly R
KR
Pechman
Deborah L
DL
Donohoe
Devyani P
DP
Bedekar
Shekar N
SN
Kurpad
Kathleen M
KM
Schmainda
D000818:Animals; D061067:Antibodies, Monoclonal, Humanized / Q000008:administration & dosage; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000008:administration & dosage*; D000068258:Bevacizumab; D001810:Blood Volume; D001811:Blood Volume Determination / Q000379:methods*; D001932:Brain Neoplasms / Q000188:drug therapy* / Q000473:pathology / Q000503:physiopathology*; D002166:Camptothecin / Q000008:administration & dosage / Q000031:analogs & derivatives; D045744:Cell Line, Tumor; D002560:Cerebrovascular Circulation; D000077146:Irinotecan; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D051381:Rats; D011923:Rats, Nude; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D016896:Treatment Outcome
D061067:Antibodies, Monoclonal, Humanized; D000068258:Bevacizumab; D000077146:Irinotecan; D002166:Camptothecin