A Prospective Histopathologic Study of Dynamic Contrast Enhanced MRI for Prostate Cancer Delineation and Characterization With the APT-MRI System
Accurate spatial delineation and biologic characterization of tumors within the prostate
gland by non-invasive means, such as MR imaging, stands to impact the spectrum of prostate
cancer care. At present there are no imaging techniques that can accurately delineate tumor
extent. With dynamic contrast enhanced MRI (DCE-MRI), signal intensity can be plotted over
time for various regions of interest within the prostate, and reflect physiological
parameters such as tissue perfusion, blood flow, vascular density and vascular permeability.
Preliminary studies suggest that malignant tumors demonstrate a more rapid and intense
uptake of contrast, as well as a more rapid washout compared with the normal peripheral
zone. However, histopathologic confirmation of these findings has been limited.
This study strives to establish a correlation between K(trans) calculated from DCE-MRI data
and the corresponding tissue histopathology. This will be achieved by acquiring needle
biopsies with the APT-MRI (Access to Prostate Tissue under MRI-guidance) system in accurate
spatial and temporal reference to DCE-MR images. The study will accrue 80 patients over a
2-year period with the primary analysis relating K(trans) to the probability of malignancy
using Generalized Estimating Equations.
Patients who have undergone a TRUS-guided biopsy for suspected prostate cancer or patients
with a pathological diagnosis of prostate cancer will be potential candidates for
enrollment. Prior to the procedure, blood will be drawn and urine collected to measure PSA
level and for protein profiling. Patients will then undergo endorectal coil MR imaging of
the prostate gland, including conventional anatomic imaging and dynamic-contrast-enhanced
MRI. During MR imaging, 4 to 10 needle biopsy cores of the prostate will be obtained using
a trans-rectal needle guide system (APT-MRI). The ability to obtain prostate biopsy cores
from all prostatic subzones and sites of interest will be documented, as will the overall
procedure time and acute toxicities associated with the procedure. Histopathology and
laboratory results of needle core biopsies will be compared to corresponding DCE-MRI
measurements, prior TRUS-biopsy results, and/or prostatectomy specimens. This procedure may
be repeated at a later time through the patient's course of observation, therapy, or follow
This is not a therapeutic trial. Patients admitted to this protocol will only be admitted
to other protocols of experimental treatments if they also specifically meet the eligibility
criteria for those protocols. Patients may derive benefit from the MRI-guided biopsy, which
will be stated in the protocol consent document.
Kevin A Camphausen, M.D.
National Cancer Institute (NCI)
United States: Federal Government
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