Use of patient-specific MRI-based prostate mold for validation of multiparametric MRI in localization of prostate cancer.
OBJECTIVE
To demonstrate the use of a patient-specific magnetic resonance imaging (MRI)-based prostate mold to generate histologic sections that directly correlate to axial MRI slices in a patient with anteriorly located prostate cancer. Anteriorly located prostate cancer has traditionally been difficult to detect on digital rectal examination and transrectal ultrasound-guided biopsy. Multiparametric MRI has potential as a valuable tool for the diagnosis and focal treatment of prostate cancer. A significant difficulty to date has been accurate correlation between the magnetic resonance images and histopathologic specimens.


METHODS
A patient-specific mold from a preoperative T2-weighted MRI scan was created to hold and shape the prostate specimen. Slots for slicing were positioned at 6-mm increments coplanar to the axial MRI slices. After surgical excision, the specimen was inked to maintain the orientation and fixed in formalin. The seminal vesicles were excised, and the prostate was oriented in the mold such that the color-coding matched the anatomic labels on the mold. The specimen was sliced with a single blade and the resultant 6-mm tissue blocks were used for histologic analysis.


RESULTS
Preoperative multiparametric MRI revealed a lesion in the right anterior transition zone that was positive on T2-weighed MRI, apparent diffusion coefficient maps of diffusion-weighted MRI, magnetic resonance spectroscopy, and dynamic contrast-enhanced MRI. The histologic sections obtained using the mold demonstrated a similar Gleason score 6 (3+3) lesion in the right anterior transition zone, correlating with the MRI findings.


CONCLUSIONS
The use of patient-specific prostate molds to register the MRI findings with the histopathologic specimen in prostate cancer could offer several benefits compared with current specimen processing techniques. This technique might further validate MRI as an accurate tool for prostate cancer localization and staging.
Center for Interventional Oncology, Radiology and Imaging Sciences, Clinical Center, Molecular Imaging Program, Urologic Oncology Branch, Laboratory of Pathology, National Cancer Institute, National Institutes of Health, Bethesda, Maryland 20892-1088, USA.
Hari
H
Trivedi
Baris
B
Turkbey
Ardeshir R
AR
Rastinehad
Compton J
CJ
Benjamin
Marcelino
M
Bernardo
Thomas
T
Pohida
Vijay
V
Shah
Maria J
MJ
Merino
Bradford J
BJ
Wood
W Marston
WM
Linehan
Aradhana M
AM
Venkatesan
Peter L
PL
Choyke
Peter A
PA
Pinto
D000368:Aged; D001707:Biopsy, Needle; D038524:Diffusion Magnetic Resonance Imaging / Q000379:methods*; D006801:Humans; D021621:Imaging, Three-Dimensional; D007150:Immunohistochemistry; D008297:Male; D060787:Neoplasm Grading / Q000379:methods; D011467:Prostate / Q000473:pathology*; D011471:Prostatic Neoplasms / Q000175:diagnosis* / Q000473:pathology; D012680:Sensitivity and Specificity; D013048:Specimen Handling