MRI to assess chemoprevention in transgenic adenocarcinoma of mouse prostate (TRAMP)

Mice were randomized into control and treated groups. The animals in treated group received 10 μmol/kg of CDDO, 5 days a week for 20 weeks. Animals underwent in vivo MRI of prostate gland and seminal vesicles by a clinical 3 Tesla MRI system just before (at 5 weeks), during and at the end of treatment, at 25 weeks. T1-weighted and fat saturation (FATSAT) multiecho fast spin echo T2- weighted images (T2WI) were acquired. Volume of the prostate glands and seminal vesicles was determined from MR images. T2 signal intensity changes in the seminal vesicles were determined by subtracting higher echo time (TE) from lower TE T2WI. Following treatments all animals were sacrificed, prostate and seminal vesicles collected, and the tissues prepared for histological staining. All data were expressed as mean ± 1 standard deviation. Two-way or multivariate analysis of variance followed by post-hoc test was applied to determine the significant differences. A p-value of <0.05 was considered significant.Histological analysis indicated tumor in 100% of control mice, whereas 10% of the treated mice showed tumor in prostate gland. Both MRI and measured prostate weights showed higher volume/weight in control mouse group. MRI showed significantly higher volume of seminal vesicles in control animals and T2 signal intensity changes in seminal vesicles of control mice indicating higher number of tumor foci, which was also proven by histology.In vivo MRI is helpful in determining the efficacy of chemoprevention of prostate cancer in TRAMP mice.According to American Cancer Society, prostate cancer is the most frequently diagnosed malignant neoplasm among men in America and is the second leading cancer in deaths. The American Cancer Society estimates that there will be 240,890 new cases of prostate cancer diagnosed and 33,720 prostate cancer specific deaths in 2011. To help solve and find a remedy for this illness, investigators in the field of prostate cancer therapy and research are using a m