title: MRI-guided 3D conformal arc micro-irradiation of a F98 glioblastoma rat model using the Small Animal Radiation Research Platform (SARRP).
abstract: Current glioblastoma (GB) small animal models for cranial radiation therapy (RT) use simple single beam technologies, which differ from the advanced conformal image-guided radiation techniques used in clinical practice. This technological disparity presents a major disadvantage for the development of new therapeutic approaches. Hence, we established a F98 GB rat model using magnetic resonance imaging (MRI)-guided three-dimensional (3D)-conformal arc RT with the Small Animal Radiation Research Platform (SARRP). Ten Fischer rats were inoculated with F98 tumor cells. When the tumor reached a volume of approximately 27 mm(3) on T2-weighted MR images, the animals were randomized into a treatment group (n = 5) receiving RT and concomitant temozolomide, and a sham group (n = 5) receiving control injections. For the treated animals, contrast-enhanced T1-weighted MR images were acquired followed by a cone-beam computed tomography (CBCT) on the SARRP system. Both scans were co-registered; MRI was used to define the target whereas CBCT was used for calculating a dose plan (20 Gy, three non-coplanar arc beams, 3 × 3 mm collimator). Tumor volumes were evaluated on follow-up contrast-enhanced T1-weighted MR images. Verification of treatment accuracy with γH2AX immunohistochemical staining was performed. Tumors in the control animals showed rapid proliferation during follow-up, encompassing almost the entire right cerebral hemisphere at day 12-15. Treated animals showed no significant tumor growth from 2 to 9 days post RT. γH2AX results confirmed the accuracy of dose delivery. This model, which is quite similar to the approach in the clinic, is valid for combined RT and chemotherapy of GB in rats.
authors: Department of Nuclear Medicine, Ghent University Hospital, De Pintelaan 185, 9000, Ghent, Belgium.
authors: Julie
authors: J
authors: Bolcaen
authors: Benedicte
authors: B
authors: Descamps
authors: Karel
authors: K
authors: Deblaere
authors: Tom
authors: T
authors: Boterberg
authors: Giorgio
authors: G
authors: Hallaert
authors: Caroline
authors: C
authors: Van den Broecke
authors: Elke
authors: E
authors: Decrock
authors: Anne
authors: A
authors: Vral
authors: Luc
authors: L
authors: Leybaert
authors: Christian
authors: C
authors: Vanhove
authors: Ingeborg
authors: I
authors: Goethals
mesh_terms: D000818:Animals; D001932:Brain Neoplasms / Q000473:pathology / Q000532:radiotherapy*; D003287:Contrast Media; D005260:Female; D005909:Glioblastoma / Q000473:pathology / Q000532:radiotherapy*; D008279:Magnetic Resonance Imaging; D011879:Radiotherapy Dosage; D011880:Radiotherapy Planning, Computer-Assisted; D020266:Radiotherapy, Conformal / Q000295:instrumentation* / Q000662:veterinary*; D061089:Radiotherapy, Image-Guided; D051381:Rats; D011916:Rats, Inbred F344; D047368:Tumor Burden
chemical_list: D003287:Contrast Media