Correlation of MR imaging and MR spectroscopic imaging findings with Ki-67, phospho-Akt, and androgen receptor expression in prostate cancer.
OBJECTIVE
To retrospectively assess whether magnetic resonance (MR) imaging and MR spectroscopic imaging and selected molecular markers correlate with each other and with clinically insignificant and significant prostate cancer (PCa), as defined at surgical pathologic analysis.


METHODS
The institutional review board approved this HIPAA-compliant study and waived informed consent. Eighty-nine men (mean age, 63 years; range, 46-79 years) with biopsy-proved PCa underwent combined endorectal MR imaging and MR spectroscopic imaging before radical prostatectomy. Suspicion of clinically insignificant PCa was retrospectively and separately recorded for MR imaging and combined MR imaging and MR spectroscopic imaging by using a scale of 0-3. Clinically insignificant PCa was pathologically defined as organ-confined cancer of 0.5 cm(3) or less without poorly differentiated elements. Prostatectomy specimens underwent immunohistochemical analysis for three molecular markers: Ki-67, phospho-Akt (pAkt), and androgen receptor (AR). To examine differences in marker levels for clinically insignificant and significant cancer, a Wilcoxon rank sum test was used. To examine correlations between marker levels and MR imaging or combined MR imaging and MR spectroscopic imaging scores, the Spearman correlation was used.


RESULTS
Twenty-one (24%) patients had clinically insignificant and 68 (76%) had clinically significant PCa at surgical pathologic review. All markers were significantly correlated with MR imaging and combined MR imaging and MR spectroscopic imaging findings (all correlation coefficients >0.5). In differentiating clinically insignificant from clinically significant PCa, areas under the receiver operating characteristic curves for Ki-67, AR, pAkt, MR imaging, and combined MR imaging and MR spectroscopic imaging were 0.75, 0.78, 0.80, 0.85, and 0.91, respectively.


CONCLUSIONS
The use of pretreatment MR imaging or combined MR imaging and MR spectroscopic imaging and molecular marker analyses of biopsy samples could facilitate better treatment selection.


BACKGROUND
http://radiology.rsnajnls.org/cgi/content/full/250/3/803/DC1.
Shukla-Dave
Amita
A
Department of Medical Physics, Memorial Sloan-Kettering Cancer Center, 1275 York Ave, New York, NY 10021, USA. davea@mskcc.org
Hricak
Hedvig
H
Ishill
Nicole M
NM
Moskowitz
Chaya S
CS
Drobnjak
Marija
M
Reuter
Victor E
VE
Zakian
Kristen L
KL
Scardino
Peter T
PT
Cordon-Cardo
Carlos
C
D000368:Aged; D015415:Biomarkers / Q000032:analysis; D006801:Humans; D019394:Ki-67 Antigen / Q000032:analysis*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D009682:Magnetic Resonance Spectroscopy / Q000379:methods*; D008297:Male; D008875:Middle Aged; D011471:Prostatic Neoplasms / Q000175:diagnosis* / Q000378:metabolism / Q000473:pathology*; D051057:Proto-Oncogene Proteins c-akt / Q000032:analysis*; D011944:Receptors, Androgen / Q000032:analysis*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013223:Statistics as Topic; D014018:Tissue Distribution
D015415:Biomarkers; D019394:Ki-67 Antigen; D011944:Receptors, Androgen; D051057:Proto-Oncogene Proteins c-akt