Do patients with a PI-RADS 5 lesion identified on magnetic resonance imaging require systematic biopsy in addition to targeted biopsy?

Prior Negative Biopsy, PSA Density, and Anatomic Location Impact Cancer Detection Rate of MRI-Targeted PI-RADS Index Lesions

BACKGROUND

MRI fusion prostate biopsy has improved the detection of clinically significant prostate cancer (CSC). Continued refinements in predicting the pre-biopsy probability of CSC are essential for optimal patient counseling. We investigated potential factors related to improved cancer detection rates (CDR) of CSC in patients with PI-RADS ≥ 3 lesions.

METHODS

The pathology of 980 index lesions in 980 patients sampled by transrectal mpMRI-targeted prostate biopsy across four medical centers between 2017-2020 was reviewed. PI-RADS lesion distribution included 291 PI-RADS-5, 374 PI-RADS-4, and 315 PI-RADS-3. We compared CDR of index PI-RADS ≥ 3 lesions based on location (TZ) vs. (PZ), PSA density (PSAD), and history of prior negative conventional transrectal ultrasound-guided biopsy (TRUS).

RESULTS

Mean age, PSA, prostate volume, and level of prior negative TRUS biopsy were 66 years (43-90), 7.82 ng/dL (5.6-11.2), 54 cm3 (12-173), and 456/980 (46.5%), respectively. Higher PSAD, no prior history of negative TRUS biopsy, and PZ lesions were associated with higher CDR. Stratified CDR highlighted significant variance across subgroups. CDR for a PI-RADS-5 score, PZ lesion with PSAD ≥ 0.15, and prior negative biopsy was 77%. Conversely, the CDR rate for a PI-RADS-4 score, TZ lesion with PSAD < 0.15, and prior negative biopsy was significantly lower at 14%.

CONCLUSIONS

For index PI-RADS ≥ 3 lesions, CDR varied significantly based on location, prior history of negative TRUS biopsy, and PSAD. Such considerations are critical when counseling on the merits and potential yield of prostate needle biopsy.

Accuracy of MRI-ultrasound fusion-guided and systematic biopsy of the prostate

OBJECTIVES

Prostate multiparametric MRI (mpMRI) with subsequent targeted biopsy of suspicious lesions has a critical role in the diagnostic workup of prostate cancer. The objective was to evaluate the diagnostic accuracy of systematic biopsies, targeted biopsies, and the combination of both in prostate cancer detection.

METHODS

From January 1, 2013 to June 1, 2022, biopsy-naïve and prior biopsy-negative patients who underwent both systematic and targeted biopsies were included. MRIs were evaluated according to PI-RADS with biopsy threshold set at PI-RADS ≥3. Systematic biopsies consisted of 8-12 cores, based on prostate volume. Overall prostate cancer and clinically significant cancer (Gleason Score ≥3 + 4) detection rates were stratified based on PI-RADS and location within the prostate, and compared between biopsy types using McNemar test.

RESULTS

Among 867 patients, 615 had prostate cancer, with 434 clinically significant cases. Overall detection rates were: PI-RADS 3 48%, PI-RADS 4 72%, and PI-RADS 5 90%. Detection rates for clinically significant cancer were 21%, 53%, and 72%, respectively. The combination of biopsy methods was most accurate in detecting clinically significant prostate cancer (P < .001). Targeted biopsies alone detected more clinically significant prostate cancer than systematic biopsies alone (43.1% vs 40.3%, P = .046). For posterior PI-RADS 5 lesions, no statistically significant difference was found between all biopsy methods.

CONCLUSIONS

In the detection of clinically significant prostate cancer, the combination of systematic and targeted biopsies proves most effective. Targeted biopsies rarely missed significant cancer for posterior PI-RADS 5 lesions, suggesting systematic biopsies could be reserved for instances where targeted biopsy results are negative.

ADVANCES IN KNOWLEDGE

This study emphasizes on the efficacy of mpMRI and targeted biopsies in suspected prostate cancer in real-world clinical context. For PI-RADS 5 lesions, systematic biopsies provide limited clinical benefit and may only be necessary when targeted biopsy results are negative.

Prediction of false-positive PI-RADS 5 lesions on prostate multiparametric MRI: development and internal validation of a clinical-radiological characteristics based nomogram

BACKGROUND

To develop a risk model including clinical and radiological characteristics to predict false-positive The Prostate Imaging Reporting and Data System (PI-RADS) 5 lesions.

METHODS

Data of 612 biopsy-naïve patients who had undergone multiparametric magnetic resonance imaging (mpMRI) before prostate biopsy were collected. Clinical variables and radiological variables on mpMRI were adopted. Lesions were divided into the training and validation cohort randomly. Stepwise multivariate logistic regression analysis with backward elimination was performed to screen out variables with significant difference. A diagnostic nomogram was developed in the training cohort and further validated in the validation cohort. Calibration curve and receiver operating characteristic (ROC) analysis were also performed.

RESULTS

296 PI-RADS 5 lesions in 294 patients were randomly divided into the training and validation cohort (208 : 88). 132 and 56 lesions were confirmed to be clinically significant prostate cancer in the training and validation cohort respectively. The diagnostic nomogram was developed based on prostate specific antigen density, the maximum diameter of lesion, zonality of lesion, apparent diffusion coefficient minimum value and apparent diffusion coefficient minimum value ratio. The C-index of the model was 0.821 in the training cohort and 0.871 in the validation cohort. The calibration curve showed good agreement between the estimation and observation in the two cohorts. When the optimal cutoff values of ROC were 0.288 in the validation cohort, the sensitivity, specificity, PPV, and NPV were 90.6%, 67.9%, 61.7%, and 92.7% in the validation cohort, potentially avoiding 9.7% unnecessary prostate biopsies.

CONCLUSIONS

We developed and validated a diagnostic nomogram by including 5 factors. False positive PI-RADS 5 lesions could be distinguished from clinically significant ones, thus avoiding unnecessary prostate biopsy.

Comparison of Targeted Biopsy and Combined Biopsy to Avoid Unnecessary Systematic Biopsy in Patients with PI-RADS 5 Lesions

PURPOSE

To evaluate the detection rates of prostate cancer (PCa) and clinically significant prostate cancer (CSPCa) detection via target biopsy (TB), systematic biopsy (SB), and combined biopsy (CB) in patients with PI-RADS 5 lesions.

METHODS

Patients with at least one PI-RADS 5 lesion were retrospectively enrolled in a prospectively collected database. The patients underwent multiparametric magnetic resonance imaging (mpMRI) followed by transrectal TB of PI-RADS 5 lesions and SB. The PCa and CSPCa detection rates and cores of TB and SB were compared with those of CB.

RESULTS

In 585 patients, prostate biopsy revealed PCa in 560 cases (95.73%) and CSPCa in 549 cases (93.85%). PCa was detected in T2 patients (93.13%, 217/233) and in T3/4 patients (97.44%, 343/352). CSPCa was detected in T2 patients (89.27%, 208/233) and in T3/4 patients (96.87%, 341/352). The positive rates of TB for T2/3/4, T3/4, and T2 were 94.02%, 96.21%, and 90.56%, respectively. SB added 1.71% (10/585) PCa and 1.37% (8/585) CSPCa detection to TB. There was no difference between TB and SB in detecting different stages of cancer (p > 0.05). In the biopsy core analysis, TB had fewer biopsy cores and a higher detection rate than SB (all p < 0.05).

CONCLUSIONS

In patients with PI-RADS score 5 lesions, TB can achieve the same detection rate as, with fewer biopsy cores than, CB. SB adds minimal clinical value and can be omitted for these patients.

Diagnostic performance of transperineal prostate targeted biopsy alone according to the PI-RADS score based on bi-parametric magnetic resonance imaging

Purpose

To compare the diagnostic performance of transperineal targeted biopsy (TB) or systematic biopsy (SB) alone based on combined TB+SB and radical prostatectomy (RP) specimen for detecting prostate cancer (PCa) according to the prostate imaging reporting and data system (PI-RADS) score.

Materials and methods

This study included 1077 men who underwent transperineal bi-parametric (bp) magnetic resonance imaging (MRI)-ultrasound (US) fusion TB+SB (bpMRI-US FTSB) between April 2019 and March 2022. To compare the performance of each modality (TB, SB, and combined TB+SB) with the RP specimen (as the standard) for detecting PCa and clinically significant PCa (csPCa), receiver operating characteristic (ROC) curves were plotted.

Results

PCa was detected in 581 of 1077 men (53.9%) using bpMRI-US FTSB. CsPCa was detected in 383 of 1077 men (35.6%), 17 of 285 (6.0%) with PI-RADS 0 to 2, 35 of 277 (12.6%) with PI-RADS 3, 134 of 274 (48.9%) with PI-RADS 4, and 197 of 241 (81.7%) with PI-RADS 5, respectively. The additional diagnostic value of TB vs. SB compared to combined TB+SB for diagnosing csPCa were 4.3% vs. 3.2% (p=0.844), 20.4% vs 5.1% (p<0.001), and 20.3% vs. 0.7% (p<0.001) with PI-RADS 3, 4, and 5, respectively. TB alone showed no significant difference in diagnostic performance for csPCa with combined TB+SB based on RP specimens in patients with PI-RADS 5 (p=0.732).

Conclusion

A need for addition of SB to TB in patients with PI-RADS 3 and 4 lesions, however, TB alone may be performed without affecting the management of patients with PI-RADS 5.

Prostate biopsy in the era of MRI-targeting: towards a judicious use of additional systematic biopsy

OBJECTIVES

We aimed to develop and compare strategies that help optimize current prostate biopsy practice by identifying patients who may forgo concurrent systematic biopsy (SBx) in favor of MRI-targeted (TBx) alone.

METHODS

Retrospective study on 745 patients who underwent combined MRI-TBx plus SBx. Primary outcome was the upgrade to clinically significant prostate cancer (csPCa; grade group ≥ 2) on SBx versus MRI-TBx. Variables (age, previous biopsy status, Prostate Imaging Reporting and Data System (PI-RADS) score, index lesion size/location, number of lesions, PSA, PSA density, prostate volume) associated with the primary outcome were identified by logistic regression and used for biopsy strategies. Clinical utility was assessed by decision curve analysis (DCA).

RESULTS

SBx detected 47 (6%) additional men with csPCa. The risk of detecting csPCa uniquely on SBx was significantly lower in men with PI-RADS 5 (versus PI-RADS 3: OR 0.30, p = 0.03; versus PI-RADS 4: OR 0.33, p = 0.01), and previous negative biopsy (versus previous positive biopsy: OR 0.40, p = 0.007), and increased with age (per 10 years: OR 1.64, p = 0.016). No significant association was observed for other variables. DCA identified the following strategies as most useful: (a) avoid SBx in men with PI-RADS 5 and (b) additionally in those with previous negative biopsy, resulting in avoiding SBx in 201 (27%) and 429 (58%), while missing csPCa in 5 (1%) and 15 (2%) patients, respectively.

CONCLUSION

Not all men benefit equally from the combination of SBx and MRI-TBx. SBx avoidance in men with PI-RADS 5 and/or previous negative biopsy may reduce the risk of excess biopsies with a low risk of missing csPCa.

KEY POINTS

• In men undergoing MRI-targeted biopsy, the risk of detecting clinically significant prostate cancer (csPCa) only on additional systematic biopsy (SBx) decreased in men with PI-RADS 5, previous negative biopsy, and younger age. • Using these variables may help select men who could avoid the risk of excess SBx. • If missing csPCa in 5% was acceptable, forgoing SBx in men with PI-RADS 5 and/or previous negative biopsy enabled the highest net reduction in SBx.

Individualized Decision Making in Transperineal Prostate Biopsy: Should All Men Undergo an Additional Systematic Biopsy?

Background: In prostate cancer (PC) diagnosis, additional systematic biopsy (SB) is recommended to complement MRI-targeted biopsy (TB) to address the limited sensitivity of TB alone. The combination of TB+SB is beneficial for diagnosing additional significant PC (sPC) but harmful in terms of the additional diagnosis of indolent PC (iPC), morbidity, and resource expenditures. We aimed to investigate the benefit of additional SB and to identify predictors for this outcome. Methods: We analyzed the frequency of upgrading to sPC by additional SB in a retrospective single-center cohort of 1043 men. Regression analysis (RA) was performed to identify predictors for this outcome. Reclassification rates of ISUP grade groups between prostate biopsy and a subsequent radical prostatectomy were assessed. Results: Additional SB led to upgrading to sPC in 98/1043 men (9.4%) and to the additional diagnosis of iPC in 71/1043 (6.8%). In RA, men harboring a PI-RADS 2-4 lesion were more likely to have TB results upgraded by SB (p < 0.01) compared to PI-RADS 5 men. When analyzing reclassification rates, additional SB reduced the upgrading to sPC from 43/214 (20.1%) to 8/214 (3.7%). In the PI-RADS 5 subgroup, this difference decreased: 4/87 (4.7%) with TB only vs. 1/87 (1.2%) with TB+SB. Conclusion: Men with a PI-RADS 5 lesion may obviate additional SB.

Assessing the need for systematic biopsies in addition to targeted biopsies according to the characteristics of the index lesion at mpMRI. Results from a large, multi-institutional database

PURPOSE

We hypothesized that systematic biopsies (SBx) value for clinically significant PCa (csPCa) detection, in addition to mpMRI targeted biopsies (TBx), may vary significantly according to mpMRI index lesion (IL) characteristics.

METHODS

We identified 1350 men with an mpMRI suspicious lesion (PI-RADS ≥ 3), defined as IL, who underwent TBx and SBx at three referral centres. The outcome was SBx added value in csPCa (grade group ≥ 2 PCa detected at SBx and missed by TBx) detection. To this aim, we performed multivariable logistic regression analyses (MVA). Furthermore, we explored the interaction between IL volume and SBx csPCa added value, across different PI-RADS categories, using lowess function.

RESULTS

Overall, 569 (42%) men had csPCa at TBx and 78 (6%) csPCa were identified at SBx only. At MVA PSA (OR 0.90; p < 0.05) and IL volume (OR 0.58; p < 0.05) were associated with SBx csPCa added value. At interaction analyses, a nonlinear correlation between PI-RADS and SBx csPCa added value was identified with a decrease from roughly 10 to 4% followed by a substantial plateau at 1.2 ml and 0.6 ml for PI-RADS 3 and 4, respectively. For PI-RADS 5 lesions SBx csPCa added was constantly lower than 4%.

CONCLUSIONS

Increasing IL volume in PI-RADS 3 and 4 lesions is associated with reduction in SBx csPCa added value. For diagnostic purposes, SBx could be omitted in men with IL larger than 1.2 ml and 0.6 ml for PI-RADS 3 and 4, respectively. Conversely, for PI-RADS 5, SBx csPCa added value was minimal regardless of IL volume.

MRI-Targeted Prostate Biopsy Techniques: AJR Expert Panel Narrative Review

Prostate cancer is the second most common malignancy in men worldwide. Systematic transrectal prostate biopsy is commonly used to obtain tissue to establish the diagnosis. However, in recent years, MRI-targeted biopsy (based on an MRI examination performed prior to consideration of biopsy) has been shown to detect more clinically significant cancer and less clinically insignificant cancer compared to systematic biopsy. This approach of performing MRI prior to biopsy has become, or is becoming, a standard of practice in centers throughout the world. This growing use of an MRI-directed pathway is leading to performance of a larger volume of MRI-targeted prostate biopsies. The three common MRI-targeted biopsy techniques are cognitive biopsy, MRI-ultrasound software fusion biopsy, and MRI in-bore guided biopsy. These techniques for using MRI information at the time of biopsy can be performed via a transrectal or transperineal approach. This narrative review presents the three MRI-targeted biopsy techniques along with their advantages and shortcomings. Comparisons among the techniques are summarized based on the available evidence. Studies to date have provided heterogeneous results, and the preferred technique remains debated.