[Hemodynamic and metabolic characterization of orthotopic rat prostate carcinomas using dynamic MRI and proton magnetic resonance spectroscopy].
OBJECTIVE
The aim of this study was the noninvasive characterization of prostate carcinoma orthotopically implanted in rats using Gd-DTPA-assisted dynamic MRI (dMRI) and proton magnetic resonance spectroscopy ((1)H-MRS).


METHODS
After surgical exposure of the prostate, Dunning R3327 orthotopic prostate carcinoma was induced by injecting cells of the MAT-LyLu subline. Six rats were examined 5 and 14 days after tumor induction with dMRI and (1)H-MRS at 1.5 T. Six tumor-free rats served as controls. Using an open two-compartment model, the parameters A (amplitude) and k(ep) (exchange rate constants) were calculated from the signal time curves of the dMRI. The relative signal intensities (Cho/Cr) of the resonances of choline (Cho) and the creatine-phosphocreatine complex (Cr) were computed from the MR spectra.


RESULTS
Already after 5 days, the tumors in the prostate could be clearly identified based on the decrease in signal intensity to T2w and increase of A and k(ep). High Cho/Cr levels and resonances of two lipid fractions (Lip(1) at 0.8-1.5 ppm and Lip(2) at 2.0-2.2 ppm) were observed by MRS in the highly necrotic tumors.


CONCLUSIONS
The orthotopic rat prostate carcinoma model resembles human prostate carcinoma in regard to MR morphology, dMRI, and (1)H-MRS. The noninvasive characterization of perfusion and metabolism makes a comparative examination of different treatment modalities possible.
Kiessling
F
F
Abteilung Onkologische Diagnostik und Therapie, Deutsches Krebsforschungszentrum (dkfz) Heidelberg. F.Kiessling@dkfz.de
Lichy
M
M
Grobholz
R
R
Heilmann
M
M
Huber
P E
PE
Meding
J
J
Peschke
P
P
Kauczor
H-U
HU
Schlemmer
H-P
HP
D000465:Algorithms; D000818:Animals; D004195:Disease Models, Animal; D006439:Hemodynamics; D006801:Humans; D007150:Immunohistochemistry; D008279:Magnetic Resonance Imaging / Q000379:methods*; D009682:Magnetic Resonance Spectroscopy; D008297:Male; D009368:Neoplasm Transplantation; D011467:Prostate / Q000033:anatomy & histology / Q000378:metabolism* / Q000473:pathology; D011471:Prostatic Neoplasms / Q000175:diagnosis* / Q000378:metabolism / Q000473:pathology / Q000503:physiopathology / Q000532:radiotherapy; D011522:Protons; D051381:Rats; D013997:Time Factors
D011522:Protons