Detection of aggressive primary prostate cancer with 11C-choline PET/CT using multimodality fusion techniques.
The aim of the study was to assess whether (11)C-choline PET/CT could identify high-risk primary adenocarcinoma of the prostate.


METHODS
(11)C-choline PET/CT and transpelvic MRI were performed in 14 patients with untreated localized primary adenocarcinoma of the prostate, followed by radical prostatectomy as a form of primary monotherapy within 14 d of in vivo imaging. To allow accurate coregistration of whole-mount histology with in vivo imaging, additional ex vivo MR images of the prostatectomy specimen were obtained. Nonlinear 3-dimensional image deformations were used for registrations of PET/CT, MRI, and histology. Volumes of interest from tumor and benign tissue were defined on the basis of histology and were transferred into coregistered (11)C-choline PET/CT volumes to calculate the mean (T((mean))/B) and maximum (T((max))/B) ratio of tumor to benign prostate background. On the basis of MIB-1/Ki-67 expression in tumor tissues represented on a tissue microarray, we assessed whether (11)C-choline uptake correlated with local Gleason score and tumor proliferation.


RESULTS
Histology confirmed 42 tumor nodules with Gleason scores between 3 + 2 and 4 + 4, with volumes ranging from 0.03 to 12.6 cm(3). T((mean))/B (P < 0.01) and T((max))/B (P < 0.001) ratios were significantly increased in high-Gleason score (>or=4 + 3) lesions versus 3 + 4 and lower disease but failed to distinguish between 3 + 4 disease versus 3 + 3 and lower. T((mean))/B and T((max))/B ratios were significantly increased in tumors with an MIB-1/Ki-67 labeling index greater than or equal to 5% (P < 0.01).


CONCLUSIONS
On the basis of our preliminary data using ratios of tumor to benign prostate background, (11)C-choline preferentially identified aggressive primary prostate cancer.
Piert
Morand
M
Department of Radiology, University of Michigan, Ann Arbor, Michigan 48109-0028, USA. mpiert@umich.edu
Park
Hyunjin
H
Khan
Asra
A
Siddiqui
Javed
J
Hussain
Hero
H
Chenevert
Thomas
T
Wood
David
D
Johnson
Timothy
T
Shah
Rajal B
RB
Meyer
Charles
C
D000368:Aged; D000465:Algorithms; D014408:Biomarkers, Tumor / Q000378:metabolism; D002250:Carbon Radioisotopes / Q000737:chemistry; D002794:Choline / Q000737:chemistry*; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D049268:Positron-Emission Tomography / Q000379:methods*; D011468:Prostatectomy; D011471:Prostatic Neoplasms / Q000175:diagnosis* / Q000235:genetics / Q000473:pathology* / Q000601:surgery; D014057:Tomography, X-Ray Computed / Q000379:methods*
D014408:Biomarkers, Tumor; D002250:Carbon Radioisotopes; D002794:Choline