Patient selection determines the prostate cancer yield of dynamic contrast-enhanced magnetic resonance imaging-guided transrectal biopsies in a closed 3-Tesla scanner

Radiation Oncology Branch, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892-1642, USA.
BJU International (Impact Factor: 3.53). 02/2008; 101(2):181-5. DOI: 10.1111/j.1464-410X.2007.07219.x
Source: PubMed


To evaluate the cancer yield of transrectal prostate biopsies in a 3-T magnetic resonance imaging (MRI) scanner in patients with elevated prostate specific antigen (PSA) levels and recent negative transrectal ultrasonography (TRUS)-guided prostate biopsies.
Between July 2004 and November 2005, patients with at least one previous negative prostate biopsy within the previous 12 months had MRI-guided biopsy of the prostate in a 3-T MRI scanner. Patients with previous positive biopsies for cancer were excluded. Target selection was based on T2-weighted imaging and dynamic contrast-enhanced (DCE) imaging studies.
Thirteen patients were eligible; their median (range) age was 61 (47-74) years and PSA value 4.90 (1.3-12.3) ng/mL. Most patients had one previous negative biopsy (range 1-4). Four patients had a family history of prostate cancer. There were 37 distinct targets based on T2-weighted imaging. Fifteen of 16 distinct DCE abnormalities were co-localized with a target based on T2-weighted imaging. Despite this correlation, only one of 13 patients had a directed biopsy positive for cancer. Including systematic biopsies, two of 13 patients had a biopsy positive for prostate cancer. One patient had prostate intraepithelial neoplasia and one had atypical glands in the specimen.
The prostate-cancer yield of transrectal biopsies in a 3-T MRI scanner, among patients with recent negative TRUS-guided prostate biopsies, is similar to repeat systematic TRUS-guided biopsy. DCE correlates with T2-imaging but does not appear to improve prostate cancer yield in this population.

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    • "mm) [34] [35]. Using this device in a study with 13 patients with at least one previous negative prostate biopsy within the previous 12 months, Singh et al [20] found only one patient with a directed biopsy positive for prostate cancer. DiMaio et al [29] [36] and Fischer et al [23] designed a robotic manipulator to perform transperineal biopsies with the patient in supine position. "
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    ABSTRACT: Systematic transrectal ultrasound-guided biopsy (TRUSBx) is the gold standard for detecting prostate cancer. This systematic approach is characterized by low sensitivity (39-52%) and high specificity (81-82%). Magnetic resonance (MR)-guided biopsy techniques are becoming more and more available, but there is no current consensus on the optimal technique. This review presents an overview of MR-guided biopsy techniques for prostate cancer detection. Current literature was reviewed regarding MR-guided biopsy for prostate cancer detection. A literature search was performed using the commercially available MedLine online search engine. Combinations of the following search and Medical Subject Headings terms were applied to retrieve relevant articles: "magnetic resonance," "prostatic neoplasms," and "biopsy." Review articles and studies describing techniques other than MR-guided biopsy were excluded. Biopsy of the prostate is an essential procedure for determining optimal treatment. Systematic TRUSBx is the gold standard, but it fails to detect numerous tumors. Diagnostic MR imaging provides more accurate selection of regions in which tumors are suspected. Using these diagnostic images during an MR-directed biopsy procedure improves quality of the biopsy. In open MR scanners, the prebiopsy images often must be registered to the real-time biopsy images because open MR scanners do not provide optimal tissue contrast; thus, the patient must first be examined in a closed MR scanner and then biopsied in an open scanner. The advantage of open MR over closed MR is that the physician has easy patient access. With special equipment, prostate MR-guided biopsy is also possible in a closed system. Closed MR scanners can be used for the prebiopsy scan as well as for the biopsy procedure. The combination of a diagnostic MR examination and MR-guided biopsy is a promising tool and may be used in patients with previous negative TRUSBx.
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    • "Our data concur with this finding[21]. Figure 3 illustrates that MR spectroscopy and DCE imaging are often unable to discriminate cancer from inflammation of the prostate. Therefore, intra-prostatic lesions as defined by MR should not be targeted for simultaneous integrated boost in the absence of biopsy proven cancer in that region. "
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