Functional characterization of prostate cancer by integrated magnetic resonance imaging and oxygenation changes during carbogen breathing.
OBJECTIVE
The objective of this study was to evaluate the changes in oxygenation of prostate cancer induced by carbogen breathing using blood oxygen level-dependent (BOLD) magnetic resonance image (MRI) with an endorectal coil (eMRI).


METHODS
In 32 patients with biopsy-proven prostate cancer, endorectal MRI was performed at 1.5 Tesla using the BOLD method. Images were acquired during 4 x 4-minute episodes alternating between room air and carbogen (95% O2/5% CO2) breathing. In each episode, 40 images were acquired (T2*-weighted EPI sequence, 12-14 slices, 3-mm thickness). All patients underwent radical prostatectomy; BOLD-MRI findings were correlated with the histopathologic results.


RESULTS
BOLD-MRI could be evaluated in 29 patients, and revealed heterogeneous signal changes of normal prostate and cancer tissue similar to the heterogeneity of prostate tissue in anatomic/pathologic preparation. A significant signal intensity increase (P = 0.004) was found in normal central gland and peripheral zone during carbogen breathing. Signal enhancement in carcinoma was significantly lower (P = 0.004) compared with the contralateral normal side.


CONCLUSIONS
Intrinsic blood-tissue contrast-functional MRI during carbogen breathing may help detect and characterize prostate carcinoma from normal tissue, particularly in small 1-sided carcinomas. This may be useful for identifying candidates for radiotherapy and monitoring noninvasive therapeutic approaches.
Diergarten
Till
T
Department of Radiology, Eberhard-Karls University Tübingen, Germany. till.diergarten@med.uni-tuebingen.de
Martirosian
Petros
P
Kottke
Raimund
R
Vogel
Ulrich
U
Stenzl
Arnulf
A
Claussen
Claus D
CD
Schlemmer
Heinz-Peter
HP
D000368:Aged; D002245:Carbon Dioxide / Q000008:administration & dosage; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D010100:Oxygen / Q000008:administration & dosage; D011471:Prostatic Neoplasms / Q000175:diagnosis* / Q000473:pathology
D002245:Carbon Dioxide; C011700:carbogen; D010100:Oxygen