How to Improve TRUS-Guided Target Biopsy following Prostate MRI

TRUS is a basic imaging modality when radiologists or urologists perform cognitive fusion or image fusion biopsy. This modality plays the role of the background images to add to an operator’s cognitive function or MRI images. Operators need to know how to make TRUS protocols for lesion detection or targeting. Tumor location, size, and shape on TRUS are different from those on MRI because the scan axis is different. TRUS findings of peripheral or transition tumors are not well known to radiologists and urologists. Moreover, it remains unclear if systematic biopsy is necessary after a tumor is targeted. The purpose of this review is to introduce new TRUS protocols, new imaging features, new biopsy techniques, and to assess the necessity of systematic biopsy for improving biopsy outcomes.

Usefulness of Prostate-Specific Antigen Density as an Indicator for Recommending Prebiopsy Magnetic Resonance Imaging to Prevent Missed Prostate Cancer Diagnoses

Purpose: To identify the indication for recommending prebiopsy magnetic resonance imaging (MRI) to prevent prostate cancer missed diagnoses in cases without prebiopsy MRI.Materials and Methods: Between January 2017 and September 2020, 585 patients suspected with prostate cancer underwent prostate biopsy after MRI. For patients with visible lesions, MRI-targeted biopsy using an image-based fusion program was performed in addition to the 12- core systematic biopsy. Patients for whom MRI was performed in other institutions (n=4) and patients who underwent target biopsy alone (n=7) were excluded.Results: Of 574 patients (median prostate-specific antigen [PSA] level, 6.88 ng/mL; mean age, 68.2 years), 342 (59.6%) were diagnosed with prostate cancer (visible lesions=312/449 [69.5%]; nonvisible lesions=30/123 [24.0%]). The detection rates of visible lesions stratified using the Prostate Imaging Reporting and Data System score (3 vs. 4 vs. 5) were 30.9% (54 of 175), 61.2% (150 of 245), and 90.1% (127 of 141), respectively. Multivariate analysis showed that PSA density was a significant factor for presence of visible lesions, prostate cancer, and significant prostate cancer diagnosis. Among patients with positive lesions, 27 (8.2%) were diagnosed with prostate cancer concomitant with negative systematic biopsy results. A PSA density of 0.15 ng/mL/cm³ was identified as the significant cutoff value for predicting positive target biopsy in groups with negative systematic biopsy. Sixty of the negative target lesions (26.1%) were diagnosed using systematic biopsy.Conclusions: To maximize cancer detection rates, both targeted and systematic biopsies should be implemented. PSA density was identified as a useful factor for recommending prebiopsy MRI to patients suspected with prostate cancer.

Real-time CEUS-guided biopsy revealing a littoral cell angioma of the spleen after inconclusive CT and MRI findings

The aim of this case report is to present real-time CEUS-guided biopsy for diagnosing rare benign splenic pathologies after inconclusive findings on cross-sectional imaging. We present the case of a 50-year-old male patient who received a contrast-enhanced computed tomography scan of the thorax during the evaluation for lung transplant due to lung fibrosis, with incidental finding of disseminated hypodense splenic lesions. During follow-up imaging, the patient did not tolerate a complete MRI examination, and two acquired pulse sequences did not confirm the final diagnosis. While CT-guided biopsy revealed no results, CEUS-guided target biopsy with repeated contrast injections showed a benign littoral cell angioma of the spleen. The use of real-time CEUS-guided target biopsy during lesion washout may be a useful tool to improve the accuracy of biopsy and accelerate the diagnosis in patients with parenchymal lesions after inconclusive cross-sectional imaging findings which may pose a challenge for CT-guided biopsy.

The value of MRI in the detection of prostate cancer in a peripheral center

Introduction: This study evaluated the value of pre-biopsy MRI and target biopsy in detection of significant prostate cancer in a peripheral center. Methods: A retrospective study included all patients of whom a MRI of the prostate was performed before biopsy, initial and repeated biopsy, between June 2016 and May 2017. Patients underwent transrectal ultrasound guided 8–12 cores prostate biopsy and cognitive fusion target biopsy was performed if a suspicious lesion was seen on MRI. The prostate cancer detection was compared between the MRI cognitive target biopsy and standard random biopsy. Results: In a total of 265 patients a MRI was performed of whom 115 underwent prostate biopsy, 96 patients underwent MRI before initial biopsies and 19 patients had previous negative biopsies. In the initial biopsy group 83 MRI’s were abnormal and only 7 (8.4%) target biopsies had an additional value in detecting or upstaging prostate cancer. Prostate cancer was found in 4 of 13 (30.8%) normal MRI’s. In the prior negative biopsy group, 4 of 18 abnormal MRI’s had an additional value in upstaging or detecting prostate cancer. Conclusion: In this study the pre-biopsy MRI had a limited additional value compared to standard biopsy in detecting or upstaging prostate cancer.

New TRUS Techniques and Imaging Features of PI-RADS 4 or 5: Influence on Tumor Targeting

PurposeTo determine if the new transrectal ultrasound (TRUS) techniques and imaging features contribute to targeting Prostate Imaging and Reporting and Data System (PI-RADS) 4 or 5.Materials and MethodsBetween December 2018 and February 2020, 115 men underwent cognitive biopsy by radiologist A, who was familiar with the new TRUS findings and biopsy techniques. During the same period, 179 men underwent magnetic resonance imaging–TRUS image fusion or cognitive biopsy by radiologist B, who was unfamiliar with the new biopsy techniques. Prior to biopsy, both radiologists knew MRI findings such as the location, size, and shape of PI-RADS 4 or 5. We recorded how many target biopsies were performed without systematic biopsy and how many of these detected higher Gleason score (GS) than those detected by systematic biopsy. The numbers of biopsy cores were also obtained. Fisher Exact or Mann–Whitney test was used for statistical analysis.ResultsFor PI-RADS 4, target biopsy alone was performed in 0% (0/84) by radiologist A and 0.8% (1/127) by radiologist B (p>0.9999). Target biopsy yielded higher GSs in 57.7% (30/52) by radiologist A and 29.5% (23/78) by radiologist B (p = 0.0019). For PI-RADS 5, target biopsy alone was performed in 29.0% (9/31) by radiologist A and 1.9% (1/52) by radiologist B (p = 0.0004). Target biopsy yielded higher GSs in 50.0% (14/28) by radiologist A and 18.2% (8/44) by radiologist B (p = 0.0079). Radiologist A sampled fewer biopsy cores than radiologist B (p = 0.0008 and 0.0023 for PI-RADS 4 and 5), respectively.ConclusionsPI-RADS 4 or 5 can be more precisely targeted if the new TRUS biopsy techniques are applied.