Dynamic magnetic resonance tomography and proton magnetic resonance spectroscopy of prostate cancers in rats treated by radiotherapy.
OBJECTIVE
To establish an experimental setting for monitoring perfusion and metabolism in orthotopic prostate cancer at 1.5 T using dynamic contrast-enhanced magnetic resonance imaging (DCE MRI) and 1H-MR spectroscopy (MRS).


METHODS
Dunning rat prostate cancer cells were injected into the prostate by open surgery. Twelve tumor-bearing rats (5 of these irradiated) and 6 healthy controls were followed up using gadolinium-diethylenetriaminepentaacetic acid -enhanced dynamic MRI and 1H-MRS. Amplitude and the exchange rate constant kep were calculated (2-compartment model). From 1H-MR spectra, ratios of choline (Cho) and creatine (tCr) were calculated. All tumors were examined histologically.


RESULTS
On DCE MRI parameter maps, tumors showed increased vascularization. kep and microvessel density were correlated (r = 0.97). Tumors showed elevated Cho/tCr and an unexpected lipid fraction (2.0-2.2 parts per million). Irradiation slowed tumor growth significantly. Changes of perfusion and metabolism could be detected in all tumors during follow up.


CONCLUSIONS
DCE MRI and 1H-MRS has potential to characterize orthotopic Dunning prostate cancer in rats, which is a promising model similar to human prostate carcinomas.
Kiessling
Fabian
F
Department of Oncological Diagnostics and Therapy, German Cancer Research Center (dkfz), Heidelberg, Germany. F.Kiessling@dkfz.de
Huber
Peter E
PE
Grobholz
Rainer
R
Heilmann
Melanie
M
Meding
Jörg
J
Lichy
Matthias P
MP
Fink
Christian
C
Krix
Martin
M
Peschke
Peter
P
Schlemmer
Heinz-Peter
HP
D000818:Animals; D018952:Antigens, CD34 / Q000032:analysis; D002794:Choline / Q000032:analysis; D003401:Creatine / Q000032:analysis; D004195:Disease Models, Animal; D007150:Immunohistochemistry; D008279:Magnetic Resonance Imaging / Q000379:methods*; D009682:Magnetic Resonance Spectroscopy; D008297:Male; D009368:Neoplasm Transplantation; D011471:Prostatic Neoplasms / Q000378:metabolism* / Q000473:pathology* / Q000532:radiotherapy; D011522:Protons; D051381:Rats; D013194:Staining and Labeling; D013997:Time Factors
D018952:Antigens, CD34; D011522:Protons; D003401:Creatine; D002794:Choline