Clinicopathologic features and outcomes of anterior-dominant prostate cancer: implications for diagnosis and treatment

The prognostic value of zonal origin in clinically localized prostate cancer: a systematic review and meta-analysis

Introduction

Correlation between zonal origin of clinically localized prostate cancer (PC) and biochemical recurrence (BCR) after treatment is still controversial.

Methods

We performed a meta-analysis of published articles to investigate the prognostic value of zonal origin in clinically localized PC. Literature was searched from Medline, Embase, Scopus, and Web of Science, from inception to Nov 1st, 2022. The risk of BCR was compared between PC originating from transition zone with peripheral zone. Relative risk (RR) was pooled in a random-effects model. Subgroup analysis and meta-regression were conducted to assess the source of heterogeneity.

Results

16 cohorts and 19,365 patients were included. PC originating from transition zone was associated with a lower risk of BCR (RR, 0.79, 95%CI; 0.69-0.92, I2, 76.8%). The association was consistent in studies with median follow-up time ≥60 months (RR, 0.65; 95%CI, 0.48 to 0.88, I2 56.8%), studies with NOS score ≥8 (RR, 0.70; 95%CI, 0.62 to 0.80, I2 32.4%), and studies using multivariate regression model (RR, 0.57; 95%CI, 0.48 to 0.69, I2 23%).

Discussion

This meta-analysis supported that transition zone origin was an independent prognostic factor of a better biochemical result in clinically localized prostate cancer after treatment.

Systematic review registration

10.37766/inplasy2023.11.0100, identifier INPLASY2023110100.

Evaluation of Patients Referred for Abnormal Digital Rectal Examination With Normal Prostate-Specific Antigen on Best Timed Pathway for Prostate Cancer

Introduction Currently, there is no recommendation for adjustments to the Best Timed Pathway for Prostate cancer (BTiPP) depending on whether the referral is for raised prostate-specific antigen (PSA) or malignant-feeling prostate on digital rectal examination (DRE). Therefore, all patients undergo MRI scanning. We aim to establish if patients with abnormal DRE only (without raised PSA) should have an adjusted pathway by comparing the biopsy rate and diagnostic yield after an MRI scan. Methods All BTiPP 2021 referral patient notes were reviewed. The patients were categorized into the aDRE group (abnormal DRE with normal PSA) or the rPSA group (raised PSA with or without abnormal DRE). Data and results for MRI and prostate biopsy were evaluated. Diagnostic yield was defined as the percentage of patients who underwent an MRI, who were diagnosed with biopsy-proven cancer. Results 68.5% (74/108) and 70.9% (282/398) of patients underwent upfront MRI in the aDRE and rPSA groups, respectively. Following MRI, the biopsy rate (28.4% (21/74) vs. 42.9% (121/282) (p=0.02)) and the biopsy-proven diagnostic yield (20.3% (15/74) vs. 36.9% (104/282) (p<0.01)) were both significantly lower in the aDRE group. 58% (43/74) of patients in the aDRE group had no posterior lesions on MRI. Only 6.7% (1/15) of biopsy-proven cancers in the aDRE group were solely anterior. Conclusions After MRI, the biopsy rate and diagnostic yield were significantly lower in the aDRE group compared to the rPSA group. Furthermore, a majority of patients referred for aDRE had a normal posterior prostate appearance on MRI. An adjusted pathway for patients referred for aDRE with normal PSA, with DRE by a urologist prior to MRI, should be considered as it would likely reduce unnecessary investigations, treatment, and patient anxiety. These data suggest that this would not risk missing significant cancers.

Clinicopathologic Significance of Anterior Prostate Cancer: Comparison With Posterior Prostate Cancer in the Era of Multiparametric Magnetic Resonance Imaging

Anterior prostate cancer (APC) has been considered an indolent tumor, most commonly arising in the transition zone (TZ). More recently, detection of APC has been facilitated through multiparametric magnetic resonance imaging and improved biopsy techniques, enabling earlier detection. The pathologic features and clinical significance of pure APC in a large contemporary series of well-characterized tumors have, to date, not been elucidated. Cases with APC defined as cancer present anterior to the urethra only were identified from 1761 consecutive radical prostatectomy specimens accessioned between January 2015 and August 2016. The clinicopathologic features of these cases were compared with those of pure posterior prostate cancer (PPC) and the features of anterior peripheral zone (APZ) cancers were compared with those of TZ cancers. In addition, the tumor series from 2015 to 2016 was compared with a cohort of 1054 patients accessioned before the utilization of multiparametric magnetic resonance imaging in the routine workup of patients with prostate cancer. In the 2015-2016 series, there were 188 (10.7%) patients with APC compared with 5.4% in the series from the pre-multiparametric magnetic resonance imaging era. No difference was observed between APC and PPC with regards to patient age or mean serum prostate-specific antigen at presentation. Mean tumor volume and positive surgical margin (PSM) rates were significantly higher in APC. In contrast, PPC was more commonly high grade with more frequent extraprostatic extension (EPE). None of the cases of APC had infiltration of the seminal vesicle or lymph node involvement, in contrast to PPC, with almost 14% of cases in each category. The 3- and 5-year biochemical recurrence-free survival was significantly higher in APC when compared with PPC, although this was not retained on multivariable analysis which included tumor location. On division of APCs according to anatomic zone of origin, 45% were APZ cancer and 37% TZ cancer. On comparison of APZ and TZ cancers, there were no significant differences in mean age and serum prostate-specific antigen at presentation as well as tumor volume, Gleason score, and PSM rate. High-grade malignancy (Gleason score >3 + 4=7) was seen in 26% of TZ cancers which compared with 44% of APZ cancers and 56% of PPC cancers. The rate of EPE was significantly higher in APZ when compared with TZ cancer ( P< 0.0005); however, the biochemical recurrence rate was not significantly different between the groups. The prevalence of APC in radical prostatectomy specimens has increased in recent times, in association with earlier detection at a stage amenable to curative surgical treatment. APC, when compared with PPC, is less commonly high grade with less frequent EPE, despite the APC group having larger tumors and a higher PSM rate at presentation. However, not all anterior cancers are indolent. Anterior cancers are more commonly seen in the APZ than the TZ and APZ cancers appear more locally aggressive than TZ cancers.

Clinical outcomes of anterior prostate cancers treated with robotic assisted radical prostatectomy

Introduction

A prospective cohort study comparing peri- and postoperative outcomes for patients with predominantly anterior prostate cancer (APC) identified preoperatively against non-anterior prostate cancer (NAPC) treated via robotic-assisted radical prostatectomy (RARP).

Patients and Methods

Of the 757 RARP's completed between January 2016 and April 2018, two comparative cohorts for anterior and an equivalent group of non-anterior prostate tumours each consisting of 152 patients were compared against each other. Data were collected on the following variables: patient age; operating consultant; preoperative PSA, ISUP grade, degree of nerve sparing; tumour staging; presence and location of positive surgical margins; PSA density, postoperative ISUP grade; treatment paradigm and postoperative PSA, erectile function, and continence outcomes with 2-year follow-up.

Results

APCs were found to have significantly lower ISUP grading postoperatively; increased diagnosis via active surveillance over new diagnosis; more frequently undertaken bilateral nerve-sparing and long-term poorer continence outcomes at 18 and 24 months postoperatively (p < 0.05). Pre- and post-op PSA levels, erectile function, PSA density, positive surgical margins (PSM), age and tumour staging showed no significant differences between the APC and NAPC cohorts (p > 0.05).

Conclusion

The lower ISUP grading could indicate APC as overall being less aggressive than NAPC, whereas the poorer long-term continence outcomes require further investigating. The non-significant differences amongst tumour staging, PSA density, preoperative PSA levels and PSM rates suggest that APC may not be as significant as predicted in diagnostic evaluation. Overall, this study provides useful information on the growing literature of anterior prostate cancer. Being the largest comparative cohort study to date on APC post-RARP, these results indicate the true characteristics of anterior tumours and their functional outcomes to help improve education, patient expectations and management.

Detection of clinically significant index prostate cancer using micro-ultrasound: correlation with radical prostatectomy

OBJECTIVE

To determine the detection of clinically significant prostate cancer (csPCa) index lesion using high resolution transrectal micro-ultrasound (MicroUS) applying PRI-MUS (Prostate Risk Identification using Micro Ultrasound) score v1.0.

METHODS

Men who underwent radical prostatectomy following biopsy and MicroUS assessment were included. MicroUS dynamic cine loops of these patients were retrospectively reviewed by an experienced radiologist. The radiologist was aware that patients had undergone radical prostatectomy but was blinded to pathological data. Suspicious sites were assigned a PRI-MUS score. Radical prostatectomy specimens were examined with quarter mount technique. Detection rate of csPCa index lesion [Grade Group (GG) ≥2] by MicroUS was assessed at a patient level.

RESULTS

Twenty-five participants were included in the analysis. The median age was 65.5 years (range 56 - 74). Median PSA was 6.45 ng/dL (range 2 - 31.72). Two of 25 patients did not have csPCa (GG1 disease) on radical prostatectomy. MicroUS visualized 20/23 (87%) of the csPCa index lesions [median length 9 mm (range 1.5- 28.5)]. All identified lesions were categorized PRIMUS score 4 or 5. The 3 missed index lesions were in the transition zone [median length 10.5 mm (range 4.5-22.5)]. MicroUS missed 11 non index csPCa in 9 participants [median length 1.5 mm (range 1.5-10.5)]. Of these, 8 were GG2, two GG3 and one GG5. MicroUS identified the csPCa index lesion in all 9 of these men.

CONCLUSION

MicroUS showed high sensitivity (87%) in detecting index lesions in the prostate gland and identified 100% of index lesions in the peripheral zone.

Prostate zones and cancer: lost in transition?

Localized prostate cancer shows great clinical, genetic and environmental heterogeneity; however, prostate cancer treatment is currently guided solely by clinical staging, serum PSA levels and histology. Increasingly, the roles of differential genomics, multifocality and spatial distribution in tumorigenesis are being considered to further personalize treatment. The human prostate is divided into three zones based on its histological features: the peripheral zone (PZ), the transition zone (TZ) and the central zone (CZ). Each zone has variable prostate cancer incidence, prognosis and outcomes, with TZ prostate tumours having better clinical outcomes than PZ and CZ tumours. Molecular and cell biological studies can improve understanding of the unique molecular, genomic and zonal cell type features that underlie the differences in tumour progression and aggression between the zones. The unique biology of each zonal tumour type could help to guide individualized treatment and patient risk stratification.

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.

Anterior or Posterior Prostate Cancer Tumor Nodule Location Predicts Likelihood of Certain Adverse Outcomes at Radical Prostatectomy

CONTEXT.—

Effect of tumor nodule (TN) location in the prostate on adverse radical prostatectomy (RP) outcomes is not well studied in contemporary cohort.

OBJECTIVE.—

To investigate the significance of TN location with respect to extraprostatic extension (EPE), seminal vesicle invasion (SV+), and positive margin status (SM+) in 1388 RPs.

DESIGN.—

Each TN at RP was independently graded, staged, and volumetrically assessed. TNs with at least 80% of their volume occupying either the anterior or posterior part of the prostate were categorized accordingly and included in our study, while all other TNs were excluded.

RESULTS.—

A total of 3570 separate TNs (median = 3 per RP; range = 1-7 per RP) were scored. There were 1320 of 3570 (37%) anterior TNs and 2250 of 3570 (63%) posterior TNs. Posterior TNs were more likely to be higher grade, and exhibit EPE (18% versus 9.4%) and SV+ (4% versus 0.15%), all P < .001. Anterior TNs with EPE were more likely to exhibit SM+ than posterior TNs with EPE (62% versus 30.8%, P < .001). TN location, grade, and volume were significant factors associated with adverse RP outcomes in our univariable analysis. When we controlled for grade and tumor volume in a multivariable analysis using anterior TN location as a reference, posterior TN location was an independent predictor of EPE and SV+ and was less likely to be associated with SM+ (odds ratio = 3.1, 81.5, and 0.7, respectively).

CONCLUSIONS.—

These associations may be useful in preoperative surgical planning, particularly with respect to improving radiographic analysis of prostate cancer.

A Combined Technology to Protect the Anatomic Integrity of Distal Urethral Sphincter Complex in Radical Prostatectomy Improves Early Urinary Continence Recovery Without Sacrifice of Oncological Outcomes

Purpose

Our primary aim was to present a combined technique to protect the anatomic integrity of distal urethral sphincter complex (DUSC) during minimally invasive radical prostatectomy (RP) and discuss its impact on urinary continence (UC) recovery. The second aim was to define the learning curve of the combined technique.

Methods

We conducted a non-randomized retrospective study. There were 314 consecutive patients who received RP by the same urologist surgeon with more than 2,000 prior cases in Shanghai Ruijin Hospital between March 2017 and April 2020. Included in this study were 263 patients with clinical T1–T2 stage. We modified a combined RP (Comb-RP) technique including endopelvic fascia no-incising technique, dorsal venous complex (DVC) no-ligation technique, intrafascial dissection technique, and anterior reconstruction technique so as to preserve the anatomic integrity of DUSC. The patients were assigned to two groups: a Comb-RP group and a conventional RP (Conv-RP) group. Continence rates were assessed every 3 months after removal of the catheter. UC was defined as 0 pad per day. Peri-operative variables of the patient including operation time, estimated blood lost (EBL), positive surgical margin (PSM), and postoperative complications were also collected. Scatter-graphs of learning curves were drawn using locally weighted scatterplot smoothing (LOWESS).

Results

RP was accomplished smoothly in all 263 cases. The pad-free UC rates in Conv-RP group and Comb-RP group were 17.3 vs. 27.8% (P = 0.048) at the removal of the catheter, 35.8 vs. 50.0% (P = 0.027) at 1 month, 60.5 vs. 76.1% (P = 0.012) at 3 months, 87.7 vs. 96.5% (P = 0.022) at 6 months, and 94.7 vs. 97.7% (P = 0.343) at 12 months. Kaplan–Meier analysis showed significantly higher and faster continence recovery in the Comb-RP group (mean 4.9 vs. 2.6 months, Log Rank P = 0.001). There was no significant difference in PSM rate between the Comb-RP and Conv-RP group (31.1 vs. 31.2%, P =0.986). The learning curves of peri-operative variables, oncological and functional outcomes achieved the lowest point or plateau at the 20th–60th cases.

Conclusions

The anatomic integrity and intact pelvic floor interplay of DUSC is important for its function. Our combined technique was a safe and feasible technique for improving early UC in RP with no significantly increased PSM rate and no significant difference in long-term UC.