title: Mathematical modeling of tumor response to radiation: radio-sensitivity correlation with BOLD, TOLD, ΔR1 and ΔR2* investigated in large Dunning R3327-AT1 rat prostate tumors.
abstract: Tumor response to radiation therapy can vary highly across patients. Several factors, both tumor- and environment-specific, can influence the radio-sensitivity, one of the most well-known being hypoxia. In this work, we investigated possible correlations between the radio-sensitivity parameters determined by means of a simple mathematical model of tumor volume evolution, and the MRI-based indicators of oxygenation in Dunning R3327-AT1 rats. Prior to irradiation the rats were subjected to an oxygen-breathing challenge, which was evaluated by MRI. The tumors were administered a single irradiation dose (30 Gy), while breathing air or oxygen. Despite a poor fitting performance, the model was able to identify two different tumor volume regression patterns. Moreover, the radio-sensitivity of the oxygen-breathing group was found to correlate with the variation of the transverse relaxation rate ΔR2* (-0.89). This suggests that MRI-based indices of tumor oxygenation may provide information about radio-sensitivity.
authors.forename: Antonella
authors.initials: A
authors.lastname: Belfatto
authors.forename: Derek A
authors.initials: DA
authors.lastname: White
authors.forename: Zhongwei
authors.initials: Z
authors.lastname: Zhang
authors.forename: Zhang
authors.initials: Z
authors.lastname: Zhang
authors.forename: Pietro
authors.initials: P
authors.lastname: Cerveri
authors.forename: Guido
authors.initials: G
authors.lastname: Baroni
authors.forename: Ralph P
authors.initials: RP
authors.lastname: Mason
mesh_terms: D000818:Animals; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008954:Models, Biological; D011471:Prostatic Neoplasms / Q000473:pathology / Q000532:radiotherapy*; D011836:Radiation Tolerance; D011879:Radiotherapy Dosage; D051381:Rats