In-bore MRI-guided prostate biopsy in a patient group with PI-RADS 4 and 5 targets: A single center experience

Multiparametric MRI to Predict Gleason Score Upgrading and Downgrading at Radical Prostatectomy Compared to Presurgical Biopsy

OBJECTIVE

This study investigated the value of multiparametric MRI (mpMRI) in predicting Gleason score (GS) upgrading and downgrading in radical prostatectomy (RP) compared with presurgical biopsy.

MATERIALS AND METHODS

Clinical and mpMRI data were retrospectively collected from 219 patients with prostate disease between January 2015 and December 2021. All patients underwent systematic prostate biopsy followed by RP. MpMRI included conventional diffusion-weighted and dynamic contrast-enhanced imaging. Multivariable logistic regression analysis was performed to analyze the factors associated with GS upgrading and downgrading after RP. Receiver operating characteristic curve analysis was used to estimate the area under the curve (AUC) to indicate the performance of the multivariable logistic regression models in predicting GS upgrade and downgrade after RP.

RESULTS

The GS after RP was upgraded, downgraded, and unchanged in 92, 43, and 84 patients, respectively. The AUCs of the clinical (percentage of positive biopsy cores [PBCs], time from biopsy to RP) and mpMRI models (prostate cancer [PCa] location, Prostate Imaging Reporting and Data System [PI-RADS] v2.1 score) for predicting GS upgrading after RP were 0.714 and 0.749, respectively. The AUC of the combined diagnostic model (age, percentage of PBCs, tPSA, PCa location, and PI-RADS v2.1 score) was 0.816, which was larger than that of the clinical factors alone (P < 0.001). The AUCs of the clinical (age, percentage of PBCs, ratio of free/total PSA [F/T]) and mpMRI models (PCa diameter, PCa location, and PI-RADS v2.1 score) for predicting GS downgrading after RP were 0.749 and 0.835, respectively. The AUC of the combined diagnostic model (age, percentage of PBCs, F/T, PCa diameter, PCa location, and PI-RADS v2.1 score) was 0.883, which was larger than that of the clinical factors alone (P < 0.001).

CONCLUSION

Combining clinical factors and mpMRI findings can predict GS upgrade and downgrade after RP more accurately than using clinical factors alone.

Can the Briganti 2019 nomogram be modified to predict lymph node metastasis risk in patients with prostate cancer detected with in-bore biopsy?

OBJECTIVES

We aimed to modify the Briganti 2019 nomogram and to test whether it is valid for patients who were diagnosed with prostate cancer through in-bore prostate biopsies.

METHODS

Data for 204 patients with positive multiparametric prostate MRI and prostate cancer identified either by mpMRI-cognitive/software fusion or in-bore biopsy and who underwent robot-assisted radical prostatectomy and extended pelvic lymph node dissection between 2012 and 2023 were retrospectively analyzed. The Briganti 2019 nomogram was applied to the mpMRI-cognitive/software fusion biopsy group (142 patients) in the original form, and then, two modifications were tested for the targeted component. Original and modified scores were compared. These modifications were adapted for the in-bore biopsy group (62 patients). The final histopathologic stage was regarded as the gold standard.

RESULTS

Nodal metastases were identified in 18/142 (12.6%) of mpMRI-cognitive/software fusion biopsy patients and 8/62 (12.9%) of the in-bore biopsy patients. In the mpMRI-cognitive/software fusion biopsy group, tumor size/core size (%) of targeted biopsy cores and positive core percentage on systematic biopsy were significant parameters for lymph node metastasis based on univariate logistic regression analyses (p < 0.05). With the modifications of these parameters for the in-bore biopsy group, V1 modification of the Briganti 2019 nomogram provided 100% sensitivity and 31.5% specificity (AUC:0.627), while V2 modification provided 75% sensitivity and 46.3% specificity (AUC:0.645).

CONCLUSIONS

Briganti 2019 nomogram may be modified by utilizing tumor size/core size (%) for targeted biopsy cores instead of positive core percentage on systematic biopsy or by not taking both parameters into consideration to detect node metastasis risk of patients diagnosed with in-bore biopsies.

MRI in-bore biopsy following MRI/US fusion-guided biopsy in patients with persistent suspicion of clinically significant prostate cancer

PURPOSE

Patients with suspicion of clinically significant prostate cancer (csPC) on multiparametric prostate MRI (mpMRI) but negative or inconclusive MRI/US fusion-guided biopsy (FB) can be challenging in clinical practice. To assess the utility of MRI in-bore biopsy (IB) in patients with discordant imaging and histopathological findings after FB.

METHODS

Consecutive patients with Prostate Imaging Reporting and Data System (PI-RADS) category 4 or 5 on mpMRI at 3T after FB without histologically confirmed csPC who underwent IB between 01/2014 and 05/2022, were retrospectively included. The primary objective was to assess the detection rate of csPC. Secondary objectives were to analyze clinical parameters, MRI parameters, and lesion localization.

RESULTS

In the final cohort of 51 patients, the IB resulted in an overall detection rate of 71% for PC and 47% for csPC. Furthermore, in 55% of cases with initial low-grade PC, the Gleason score was upgraded after IB. CsPC was often detected apical and/or anterior. The detection rate for PC was 58% in PI-RADS category 4 and 94% in PI-RADS category 5 (csPC 39% and 61%, respectively). Patients with csPC had statistically significant smaller prostate volumes, a higher PI-RADS category, a higher prostate-specific antigen density (PSAD), and were older.

CONCLUSIONS

For a relevant proportion of patients with PI-RADS category 4 or 5 and negative or inconclusive findings on previous FB, but with persistent suspicion of csPC, a subsequent IB verified the presence of csPC. Therefore, IB can be a backup in cases of uncertainty.

Machine learning prediction of Gleason grade group upgrade between in-bore biopsy and radical prostatectomy pathology

This study aimed to enhance the accuracy of Gleason grade group (GG) upgrade prediction in prostate cancer (PCa) patients who underwent MRI-guided in-bore biopsy (MRGB) and radical prostatectomy (RP) through a combined analysis of prebiopsy and MRGB clinical data. A retrospective analysis of 95 patients with prostate cancer diagnosed by MRGB was conducted where all patients had undergone RP. Among the patients, 64.2% had consistent GG results between in-bore biopsies and RP, whereas 28.4% had upgraded and 7.4% had downgraded results. GG1 biopsy results, lower biopsy core count, and fewer positive cores were correlated with upgrades in the entire patient group. In patients with GG > 1 , larger tumor sizes and fewer biopsy cores were associated with upgrades. By integrating MRGB data with prebiopsy clinical data, machine learning (ML) models achieved 85.6% accuracy in predicting upgrades, surpassing the 64.2% baseline from MRGB alone. ML analysis also highlighted the value of the minimum apparent diffusion coefficient ( ADC min ) for GG > 1 patients. Incorporation of MRGB results with tumor size, ADC min value, number of biopsy cores, positive core count, and Gleason grade can be useful to predict GG upgrade at final pathology and guide patient selection for active surveillance.

The role of the size and number of index lesion in the diagnosis of clinically significant prostate cancer in patients with PI-RADS 4 lesions who underwent in-bore MRI-guided prostate biopsy

PURPOSE

To evaluate the contribution of the size and number of the sampled lesions to the diagnosis of clinically significant prostate cancer (CSPC) in patients who had PI-RADS 4 lesions.

METHODS

In this retrospective study, a total of 159 patients who had PI-RADS 4 lesions and underwent In-bore MRI-Guided prostate biopsy were included. Patients with a lesion classified as Grade Group 2 and above were considered to have CSPC. Univariate and multivariate regression analyses were used to evaluate the factors affecting the diagnosis of prostate cancer (PCa) and CSPC.

RESULTS

A great majority (86.8%) of the patients were biopsy-naïve. About three-fourths (71.7%) had PCa, and half (54.1%) had CSPC. When the patients were divided into three groups according to the index lesion size (< 5 mm, 5-10 mm, and > 10 mm), the prevalence of PCa was 64.3, 67.5, and 82.4% and the prevalence of CSPC was 42.9, 51.2, and 64.7%, respectively. In multivariate analysis, age, index lesion size, prostate volume (< 50 ml) and being biopsy-naïve were found significant for PCa, while age and prostate volume (< 50 ml) were significant for CSPC.

CONCLUSION

The number of lesions was found to be insignificant in predicting PCa and CSPC. While the size of PI-RADS 4 lesions was significant in predicting PCa, it had no significance in detecting CSPC.

The use of advanced imaging in guiding the further investigation and treatment of primary prostate cancer

In the era of precision medicine, oncological imaging techniques are advancing at a rapid pace, particularly molecular imaging with promising new targets for prostate cancer (PC) such as gastrin releasing peptide receptors (GRPR) along the established and indispensable prostate specific membrane antigen (PSMA). As PC is characterized by heterogenous tumor biology ranging from indolent to aggressive disease, distinguishing clinically significant tumors from indolent disease is critical. Multiparametric MRI- and PET-targeted prostate biopsies mitigate the shortcomings and risks of standard systematic template biopsy by identifying more significant cancers.Focal treatment for localized disease is a minimally invasive approach that targets the index tumor - the lesion of the highest grade - while sparing the surrounding healthy tissue. Real-time MRI-guidance and thermal control with MR-thermometry, improves treatment accuracy and results in lower rates of functional side effects. PET imaging could be an useful tool to assess response to treatment compared to invasive prostate biopsies.In this comprehensive review, we focus on the image-guided detection and treatment of localized primary prostate cancer, its current status and future perspectives.