Usability and diagnostic accuracy of different MRI/ultrasound-guided fusion biopsy systems for the detection of clinically significant and insignificant prostate cancer: a prospective cohort study

MRI software and cognitive fusion biopsies in people with suspected prostate cancer: a systematic review, network meta-analysis and cost-effectiveness analysis

Background

Magnetic resonance imaging localises cancer in the prostate, allowing for a targeted biopsy with or without transrectal ultrasound-guided systematic biopsy. Targeted biopsy methods include cognitive fusion, where prostate lesions suspicious on magnetic resonance imaging are targeted visually during live ultrasound, and software fusion, where computer software overlays the magnetic resonance imaging image onto the ultrasound in real time. The effectiveness and cost-effectiveness of software fusion technologies compared with cognitive fusion biopsy are uncertain.

Objectives

To assess the clinical and cost-effectiveness of software fusion biopsy technologies in people with suspected localised and locally advanced prostate cancer. A systematic review was conducted to evaluate the diagnostic accuracy, clinical efficacy and practical implementation of nine software fusion devices compared to cognitive fusion biopsies, and with each other, in people with suspected prostate cancer. Comprehensive searches including MEDLINE, and Embase were conducted up to August 2022 to identify studies which compared software fusion and cognitive fusion biopsies in people with suspected prostate cancer. Risk of bias was assessed with quality assessment of diagnostic accuracy studies-comparative tool. A network meta-analysis comparing software and cognitive fusion with or without concomitant systematic biopsy, and systematic biopsy alone was conducted. Additional outcomes, including safety and usability, were synthesised narratively. A de novo decision model was developed to estimate the cost-effectiveness of targeted software fusion biopsy relative to cognitive fusion biopsy with or without concomitant systematic biopsy for prostate cancer identification in biopsy-naive people. Scenario analyses were undertaken to explore the robustness of the results to variation in the model data sources and alternative assumptions.

Results

Twenty-three studies (3773 patients with software fusion, 2154 cognitive fusion) were included, of which 13 informed the main meta-analyses. Evidence was available for seven of the nine fusion devices specified in the protocol and at high risk of bias. The meta-analyses show that patients undergoing software fusion biopsy may have: (1) a lower probability of being classified as not having cancer, (2) similar probability of being classified as having non-clinically significant cancer (International Society of Urological Pathology grade 1) and (3) higher probability of being classified at higher International Society of Urological Pathology grades, particularly International Society of Urological Pathology 2. Similar results were obtained when comparing between same biopsy methods where both were combined with systematic biopsy. Evidence was insufficient to conclude whether any individual devices were superior to cognitive fusion, or whether some software fusion technologies were superior to others. Uncertainty in the relative diagnostic accuracy of software fusion versus cognitive fusion reduce the strength of any statements on its cost-effectiveness. The economic analysis suggests incremental cost-effectiveness ratios for software fusion biopsy versus cognitive fusion are within the bounds of cost-effectiveness (£1826 and £5623 per additional quality-adjusted life-year with or with concomitant systematic biopsy, respectively), but this finding needs cautious interpretation.

Limitations

There was insufficient evidence to explore the impact of effect modifiers.

Conclusions

Software fusion biopsies may be associated with increased cancer detection in relation to cognitive fusion biopsies, but the evidence is at high risk of bias. Sufficiently powered, high-quality studies are required. Cost-effectiveness results should be interpreted with caution given the limitations of the diagnostic accuracy evidence.

Study registration

This trial is registered as PROSPERO CRD42022329259.

Funding

This award was funded by the National Institute for Health and Care Research (NIHR) Evidence Synthesis programme (NIHR award ref: 135477) and is published in full in Health Technology Assessment; Vol. 28, No. 61. See the NIHR Funding and Awards website for further information.

Safety and efficacy of software-assisted MRI-TRUS fusion-guided transperineal prostate biopsy in an outpatient setting using local anaesthesia

PURPOSE

To evaluate diagnostic accuracy, safety, and efficiency of an MRI-TRUS fusion-guided transperineal prostate biopsy method in an outpatient setting under local anaesthesia.

METHODS

Patients undergoing transperineal prostate biopsy were included from March 2021 to May 2022. Biopsies were performed under local anaesthesia in an outpatient setting, using specialised fusion software. Primary outcome was (clinically significant) cancer detection rate. Secondary outcomes were procedure time, patient discomfort during the procedure and complication rate.

RESULTS

We included 203 male patients (69 years +-SD 8.2) with PI-RADS score > 2. In total 223 suspicious lesions were targeted. Overall cancer detection rate and clinically significant cancer detection rate were 73.5% and 60.1%, respectively. (Clinically significant) cancer detection rates in PI-RADS 3, 4 and 5 lesions were 46.4% (23.2%), 78.5% (66.1%) and 93.5% (89.1%), respectively. Mean duration of the procedure including fusion, targeted and systematic biopsies was 22.5 min. Patients rated injection of local anaesthesia on a numeric pain rating scale on average 3.7/10 (SD 2.09) and biopsy core sampling 1.6/10 (SD 1.65). No patient presented with acute urinary retention on follow-up consultation. Two (1%) patients presented with infectious complications. Four (2%) patients experienced a vasovagal reaction.

CONCLUSION

Transperineal targeted biopsy with MRI-TRUS fusion software has high overall and clinically significant cancer detection rates. The method is well tolerated under local anaesthesia and in an outpatient setting.

[Image-guided biopsy of the prostate gland]

The recommendations on carrying out a multiparametric magnetic resonance imaging (mpMRI) for the primary diagnostics and during active surveillance of prostate cancer, include as a consequence an image-guided sampling from conspicuous areas. In doing so, the information on the localization provided by mpMRI is used for a targeted biopsy of the area suspected of being a tumor. The targeted sampling is mainly performed under sonographic control and after fusion of MRI and ultrasound but can also be (mostly in special cases) carried out directly in the MRI scanner. In an ultrasound-guided biopsy, it is vital to coregister the MR images with the ultrasound images (segmentation of the contour of the prostate and registration of suspect findings). This coregistration can either be carried out cognitively (transfer by the person performing the biopsy alone) or software based. Each method shows specific advantages and disadvantages in the prioritization between diagnostic accuracy and resource expenditure.

Impact of Surgeon's Experience in Rigid versus Elastic MRI/TRUS-Fusion Biopsy to Detect Significant Prostate Cancer Using Targeted and Systematic Cores

Simple Summary

For the transfer of suspicious lesions in magnetic resonance imaging (MRI) to ultrasound in prostate fusion biopsy, biopsy platforms can be distinguished by rigid or elastic image registration. This study evaluates the detection rate of these different platforms for transperineal fusion-guided prostate biopsy to detect clinically significant prostate cancer under consideration of the surgeon’s learning curve. In our cohort, rigid and elastic registration systems showed a similar prostate cancer detection rate in experienced surgeons, whereas novices seem to benefit from rigid fusion. In the total cohort, targeted fusion biopsy with a rigid registration system outperformed elastic registration target biopsy with a superior significant prostate cancer detection rate, each compared to systematic saturation biopsy. Thus, rigid target biopsy aided in reducing targeting errors that result in missing MRI-visualized significant prostate cancer. These results can provide valuable decision support in selecting a biopsy fusion platform to increase the detection rate and risk stratification of prostate cancer, especially at the beginning of the surgeon’s learning curve.

Abstract

Multiparametric magnetic resonance imaging (mpMRI) and MRI/ultrasound fusion-targeted prostate biopsy (FB) have excellent sensitivity in detecting significant prostate cancer (sPC). FB platforms can be distinguished by rigid (RTB) or elastic image registration (ETB). We compared RTB and ETB by analyzing sPC detection rates of both RTB and ETB at different stages of the surgeons’ learning curve. Patients undergoing RTB between 2015–2017 (n = 502) were compared to patients undergoing ETB from 2017–2019 (n = 437). SPC detection rates were compared by Chi-square-test on patient-basis. Combination of transperineal systematic biopsy and each TB served as reference and sub-analyses were performed for different grades of surgeon’s experience. In the RTB subgroup, 233 men (46%) had sPC, compared to 201 (46%) in the ETB subgroup. RTB alone detected 94% of men with sPC and ETB 87% (p = 0.02). However, for at least intermediate-experienced surgeons (>100 FB), no differences occurred between RTB and ETB. In the total cohort, at least intermediate-experienced surgeons detected significantly more sPC (10%, p = 0.008) than novices. Thus, targeted transperineal MRI/TRUS-FB with a RTB registration system showed a similar sPC detection rate to ETB in experienced surgeons but a superior sPC detection rate to ETB in the total cohort. Low-experienced surgeons seem to benefit from RTB.

Comparison of prostate cancer detection rates in patients undergoing MRI/TRUS fusion prostate biopsy with two different software-based systems

BACKGROUND

Magnetic resonance imaging (MRI)-targeted prostate biopsy is a routinely used diagnostic tool for prostate cancer (PCa) detection. However, a clear superiority of the optimal approach for software-based MRI processing during biopsy procedures is still unanswered. To investigate the impact of robotic approach and software-based image processing (rigid vs. elastic) during MRI/transrectal ultrasound (TRUS) fusion prostate biopsy (FBx) on overall and clinically significant (cs) PCa detection.

METHODS

The study relied on the instructional retrospective biopsy data collected data between September 2013 and August 2017. Overall, 241 men with at least one suspicious lesion (PI-RADS ≥ 3) on multiparametric MRI underwent FBx. The study protocol contains a systematic 12-core sextant biopsy plus 2 cores per targeted lesion. One experienced urologist performed 1048 targeted biopsy cores; 467 (45%) cores were obtained using rigid processing, while the remaining 581 (55%) cores relied on elastic image processing. CsPCa was defined as International Society of Urological Pathology (ISUP) grade ≥ 2. The effect of rigid versus elastic FBx on overall and csPCa detection rates was determined. Propensity score weighting and multivariable regression models were used to account for potential biases inherent to the retrospective study design.

RESULTS

In multivariable regression analyses, age, prostate-specific antigen (PSA), and PIRADS ≥ 3 lesion were related to higher odds of finding csPCa. Elastic software-based image processing was independently associated with a higher overall PCa (odds ratio [OR] = 3.6 [2.2-6.1], p < 0.001) and csPCa (OR = 4.8 [2.6-8.8], p < 0.001) detection, respectively.

CONCLUSIONS

Contrary to existing literature, our results suggest that the robotic-driven software registration with elastic fusion might have a substantial effect on PCa detection.

Diagnostic performance of fusion (US/MRI guided) prostate biopsy: propensity score matched comparison of elastic versus rigid fusion system

PURPOSE

Many software for US/MRI guided fusion prostate biopsy (FPB), have been developed in the last years. However, there are few data comparing diagnostic accuracy of different fusion systems. We assessed diagnostic performance of elastic (EF) versus rigid fusion (RF) PB in a propensity score matched (PSM) analysis.

METHODS

A total of 314 FPB were prospectively collected from two different centers. All patients were biopsy naïve and all mpMRI reported a single suspicious area. Overall, 211 PB were performed using a RF system and 103 using an EF software. The two groups were compared for the main clinical features. A 1:1 PSM analysis was employed to reduce covariate imbalance to < 10%. Detection rate (DR) for any prostate cancer (PCa) and clinically significant (cs) PCa were compared and stratified for PI-RADS Score. A per target univariable and multivariable regression analyses were applied to identity predictors of anyPCa and csPCa.

RESULTS

After applying the PSM, two cohorts of 83 cases were selected. DR of any PCa cancer and csPCa were comparable between the two cohorts (all p > 0.077) as well as DR of csPCa for every PIRADS score. At univariable regression analysis lesion size, PI-RADS Score, PSA Density and EF system were predictors of any PCa (all p < 0.001); however, at multivariable analysis only PI-RADS Score was independent predictor of any PCa (p = 0.027). At multivariable analysis only PI-RADS score was independent predictor of csPCa.

CONCLUSIONS

Fusion PB guarantees high diagnostic accuracy for csPCa, regardless of the fusion technology. Prospective randomized study is needed to confirm these data.

Comparison of Accuracies between Real-Time Nonrigid and Rigid Registration in the MRI-US Fusion Biopsy of the Prostate

Magnetic resonance imaging (MRI) is increasingly important in the detection and localization of prostate cancer. Regarding suspicious lesions on MRI, a targeted biopsy using MRI fused with ultrasound (US) is widely used. To achieve a successful targeted biopsy, a precise registration between MRI and US is essential. The purpose of our study was to show any decrease in errors using a real-time nonrigid registration technique for prostate biopsy. Nineteen patients with suspected prostate cancer were prospectively enrolled in this study. Registration accuracy was calculated by the measuring distance of corresponding points by rigid and nonrigid registration between MRI and US, and compared for rigid and nonrigid registration methods. Overall cancer detection rates were also evaluated by patient and by core. Prostate volume was measured automatically from MRI and manually from US, and compared to each other. Mean distances between the corresponding points in MRI and US were 5.32 ± 2.61 mm for rigid registration and 2.11 ± 1.37 mm for nonrigid registration (p < 0.05). Cancer was diagnosed in 11 of 19 patients (57.9%), and in 67 of 266 biopsy cores (25.2%). There was no significant difference in prostate-volume measurement between the automatic and manual methods (p = 0.89). In conclusion, nonrigid registration reduces targeting errors.