Pathology of the prostate in radical cystectomy specimens: A critical review

Naturally-Occurring Invasive Urothelial Carcinoma in Dogs, a Unique Model to Drive Advances in Managing Muscle Invasive Bladder Cancer in Humans

There is a great need to improve the outlook for people facing urinary bladder cancer, especially for patients with invasive urothelial carcinoma (InvUC) which is lethal in 50% of cases. Improved outcomes for patients with InvUC could come from advances on several fronts including emerging immunotherapies, targeted therapies, and new drug combinations; selection of patients most likely to respond to a given treatment based on molecular subtypes, immune signatures, and other characteristics; and prevention, early detection, and early intervention. Progress on all of these fronts will require clinically relevant animal models for translational research. The animal model(s) should possess key features that drive success or failure of cancer drugs in humans including tumor heterogeneity, genetic-epigenetic crosstalk, immune cell responsiveness, invasive and metastatic behavior, and molecular subtypes (e.g., luminal, basal). Experimental animal models, while essential in bladder cancer research, do not possess these collective features to accurately predict outcomes in humans. These key features, however, are present in naturally-occurring InvUC in pet dogs. Canine InvUC closely mimics muscle-invasive bladder cancer in humans in cellular and molecular features, molecular subtypes, immune response patterns, biological behavior (sites and frequency of metastasis), and response to therapy. Thus, dogs can offer a highly relevant animal model to complement other models in research for new therapies for bladder cancer. Clinical treatment trials in pet dogs with InvUC are considered a win-win-win scenario; the individual dog benefits from effective treatment, the results are expected to help other dogs, and the findings are expected to translate to better treatment outcomes in humans. In addition, the high breed-associated risk for InvUC in dogs (e.g., 20-fold increased risk in Scottish Terriers) offers an unparalleled opportunity to test new strategies in primary prevention, early detection, and early intervention. This review will provide an overview of canine InvUC, summarize the similarities (and differences) between canine and human InvUC, and provide evidence for the expanding value of this canine model in bladder cancer research.

The prognostic impact of incidental prostate cancer following radical cystoprostatectomy: a nationwide analysis

BACKGROUND

To determine the prevalence and prognostic impact of incidental prostate cancer in patients undergoing radical cystoprostatectomy.

METHODS

A nationwide population-based study of incidental prostate cancer diagnosed following radical cystoprostatectomy. Information on vital status, Gleason score, positive and negative tumor margins, pT-category and subsequent prostate cancer therapies were obtained from the Danish Prostate Cancer Registry and by manual chart review.

RESULTS

A total of 1,450 men who underwent radical cystoprostatectomy in Denmark from 1995-2011 were identified. Forty-six men were excluded from analysis, thus 1,404 patients were eligible. The median follow-up was 7.8 years. A total of 466 (33.2%) had incidental prostate cancer diagnosed. No statistical differences in 10- and 15-year cumulative overall mortality were observed when comparing men with, or without, incidental prostate cancer. In men diagnosed with incidental prostate cancer, neither Gleason score, positive surgical margins or locally advanced prostate cancer (pT3-4) was associated with mortality. Only 0.9% received post-operative prostate cancer-related treatment.

CONCLUSION

In this population-based cohort of patients with incidental prostate cancer diagnosed at radical cystoprostatectomy, we found no impact of incidental prostate cancer on overall mortality, regardless of Gleason score, surgical margin status and pathological T-category. Patients diagnosed with incidental prostate cancer following radical cystoprostatectomy are unlikely to benefit from additional follow-up.

Prevalence and clonality of synchronous primary carcinomas in the bladder and prostate

Incidental prostate adenocarcinoma (IPCa) has been frequently discovered during postoperative histopathological evaluation of radical cystoprostatectomy specimens in patients with bladder cancer (BCa). However, there is currently no conclusive study addressing the clinical significance of IPCa and the clonal relatedness of IPCa and BCa. Here, we performed a retrospective single-center review of 919 BCa cases and an additional meta-analysis including a total of 19 868 individuals who underwent radical cystectomy for bladder cancer. IPCa, mostly clinically insignificant, was detected in 67 of 919 BCa patients (7.3%) and was significantly associated with greater age. In the meta-analysis, a lower prevalence was observed in Asian than in non-Asian countries (19% versus 32%), presumably due to their different rates of prostate cancer occurrence. Whole-exome sequencing on matched BCa and IPCa samples unambiguously revealed independent clonal origins of the synchronous tumors. BCa and IPCa lesions from each patient displayed distinctive genomic abnormalities and largely unrelated mutational signatures of single nucleotide variations, indicating disparate mutational processes underlying bladder and prostate oncogenesis. These findings provide important insights into the incidental nature of prostate adenocarcinoma in patients with bladder cancer, and suggest that the two concurrent diseases can be managed separately. Copyright © 2017 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.

Incidental Prostate Adenocarcinoma in Cystoprostatectomy Specimens: Partial Versus Complete Prostate Sampling

BACKGROUND

The rate of incidental prostate adenocarcinoma (PCa) detection in radical cystoprostatectomy (RCP) varies widely, ranging from 15% to 54%. Such variability may be explained by institutional differences in prostate grossing protocols. Either partial or complete submission of the prostate gland in RCP may result in detection of clinically insignificant or significant incidental PCa. The aim of the study was to compare the clinical significance of PCa in RCP specimens in partial versus complete sampling.

MATERIAL

Seventy-two out of 158 RCP cases showed incidental PCa. The pathologic features, including Gleason score, margin status, extraprostatic extension (EPE), seminal vesicle invasion (SVI), PCa stage, and tumor volume, were assessed.

RESULTS

The 72 cases were divided into partial (n = 21, 29.1%) and complete sampling (n = 51, 70.8%) groups. EPE was detected in 13/72 (18.1%) with 11/13 (84.6%) cases in the complete group. Positive margins were present in 11/72 (15.3%) with 9/11 (81.8%) in the complete group. SVI was detected in 4/72 (5.6%) with 3/4 (75.0%) in the complete group. Overall, 4/72 (5.6%) had a Gleason score >7, all of which were in the complete group.

CONCLUSION

Our data suggest that complete sampling of the prostate may be the ideal approach to grossing RCP specimens, allowing for greater detection of clinically significant incidental PCa.

Prostate Health Index and %p2PSA Predict Aggressive Prostate Cancer Pathology in Chinese Patients Undergoing Radical Prostatectomy

PURPOSE

To investigate the performance of prostate health index (PHI) and percentage prostate-specific antigen (PSA) isoform [-2]proPSA (%p2PSA) in predicting pathologic outcomes at radical prostatectomy (RP) in a Chinese population.

METHODS

We performed a prospective study of 135 prostate cancer patients with RP. The accuracy of preoperative %p2PSA (= p2PSA/free PSA) and PHI [= (p2PSA/free PSA) × √PSA] in predicting pathologic outcomes of RP including pT3 disease, pathologic Gleason score (pGS) ≥7, Gleason score (GS) upgrade at RP, tumor volume >0.5 ml, and Epstein criteria for significant tumor were calculated using multivariate analyses and area under the curve. The base model in multivariate analysis included age, PSA, abnormal digital rectal examination, and biopsy GS.

RESULTS

PHI was significantly higher in patients with pT3 or pGS ≥ 7 (p < 0.001), pT3 disease (p = 0.001), pGS ≥ 7 (p < 0.001), GS upgrade (p < 0.001), tumor volume >0.5 ml (p < 0.001), and Epstein criteria for significant tumor (p = 0.001). %p2PSA was also significantly higher in all the above outcomes. The risk of pT3 or pGS ≥ 7 was 16.1 % for PHI < 35 and 60.8 % for PHI > 35 (sensitivity 84.2 %, specificity of 60.3 %), and the risk of tumor volume >0.5 ml was 25.5 % for PHI < 35 and 72.6 % for PHI > 35 (sensitivity 79.1 %, specificity 67.2 %). In multivariate analysis, adding %p2PSA or PHI to the base model significantly improved the accuracy (area under the curve) in predicting pT3 or pGS ≥ 7 (by 7.2-7.9 %), tumor volume >0.5 ml (by 10.3-12.8 %), and Epstein criteria for significant tumor (by 13.9-15.9 %). Net clinical benefit was observed in decision curve analyses for prediction of both tumor volume >0.5 ml, and pT3 or pGS ≥ 7.

CONCLUSIONS

Both PHI and %p2PSA predict aggressive and significant pathologies in RP in Chinese men. This enabled identification of nonaggressive cancers for better counseling on active surveillance or treatment.

Incidental prostate cancer in Asian men: high prevalence of incidental prostatic adenocarcinoma in Chinese patients undergoing radical cystoprostatectomy for treatment of bladder cancer and selection of candidates for prostate-sparing cystectomy

BACKGROUND

Previous studies report a low prevalence of incidental prostate cancer in Chinese patients (3-7%). We evaluated incidental prostatic adenocarcinoma (PCa) and urothelial carcinoma (UCa) involvement of the prostate in cystoprostatectomy specimens.

METHODS

We analyzed 340 cystoprostatectomy specimens from patients who underwent radical cystoprostatectomy for the treatment of bladder cancer in China from 2004 to 2014. None of the patients had known prostate cancer prior to cystoprostatectomy.

RESULTS

Overall, 180 (53%) patients had either PCa or UCa in the prostate. We found that 95 (28%) had PCa and 115 (34%) had UCa involvement of prostate. The rate of incidental prostate cancer was 21% and 31%, respectively, from two study periods (2004-2008 and 2009-2014). Among the 95 patients with PCa, 19 (20%) had Gleason score of ≥7, nine (10%) had PCa tumor volume >0.5 cc, and eight (8.4%) had extracapsular extension. Of the 115 with prostatic UCa, 61 had prostatic urethra and/or periurethral prostatic duct involvement only, while 54 had prostatic stromal invasion. Age (odds ratio [OR] = 1.04, P = 0.001), increasing stage of bladder tumor (OR = 1.28, P = 0.005), multifocal tumors of bladder (OR = 3.22, P < 0.001), carcinoma in situ (CIS) in the bladder (OR = 5.52, P < 0.001), and bladder neck involvement (OR = 6.12, P < 0.001) were strongly associated with prostatic UCa.

CONCLUSIONS

The rate of incidental PCa in cystoprostatectomy specimens in China has increased over the last decade. Patients with advanced age, elevated serum PSA level, advanced bladder tumor stage, multifocal bladder tumors, CIS in the bladder, and tumor location at the bladder neck should be excluded as candidates for prostate-sparing cystectomy.

The incidence of prostate cancer and urothelial cancer in the prostate in cystoprostatectomy specimens in a tertiary care Canadian centre

INTRODUCTION

Radical cystoprostatectomy remains the gold standard treatment for muscle invasive bladder cancer. However, given the treatment related complications of compromised potency and continence with this procedure, prostate/sexuality sparing cystectomy in orthotopic neobladder candidates has emerged in an effort to minimize these quality of life concerns. Recent evidence suggests only a marginal functional benefit from these technical refinements. We sought to determine the incidence of occult prostate cancer and urothelial cancer of the prostate in cystoprostatectomy specimens conducted for muscle invasive bladder cancer.

METHODS

We retrospectively reviewed 83 male patients who underwent radical cystoprostatectomy for muscle invasive bladder cancer between April 2004 and March 2007. The median age of our study group was 71 years. Pathologic findings of prostate/urothelial cancer in the prostate were identified. Clinically significant prostate cancer was defined as Gleason score >6, tumour volume >0.5cc, extracapsular extension or perineural invasion.

RESULTS

Our review yielded a 30% (±10%, 0.95 CI) rate of prostate cancer, with 19% (± 8.5%, 0.95 CI) of total specimens being positive for clinically significant prostate cancer. Urothelial cancer in the prostate was identified in 16% (±8.5%, 0.95 CI) of patients, with an overlap with prostate cancer in 2 patients. The overall rate of an underlying cancer within the prostate of our cystoprostatectomy specimens was about 46% (±10.7%, 0.95 CI).

CONCLUSION

These findings suggest that the oncological risk of leaving behind residual cancer may not justify the practice of prostate-sparing cystectomies.

Incidentally found prostate cancer and influence on overall survival after radical cystoprostatectomy

Objectives. To determine incidentally found prostate cancer frequency and impact on overall survival after RCP. Patients and Methods. The records of 81 men who underwent cystoprostatectomy from January 2000 to December 2009 were reviewed. The vital status of the study group was assessed as on September 1, 2009, by passive followup, using data from the population registry. Results. The 81 men underwent RCP. The incidental prostate cancer was found in the specimens of 27 (33.3%) patients. 13 (48.1%) of 27 prostate cancer cases were clinically significant. For 3 patients (11.1%) an extraprostatic extension was found. For 2 patients (7.4%)—positive margins, for 1 patient (3.7%)—Gleason sum 8, and for the rest 7 patients bigger than 0.5 cm³ volume tumor, and Gleason sum 7 was found. The mean follow-up time was 39.2 ± 33.8 months (varies from 0.8 to 131.2 months). The patients with bladder cancer and incidentally found prostate cancer lived shorter (28.1 ± 27.5 and 45.5 ± 35.40 months). Higher overall survival (P = 0.03) was found in the patient group with bladder cancer without incidentally diagnosed prostate cancer. Conclusion. There are indications that in this small study prostate cancer has influenced on patients' survival with bladder cancer after radical cystoprostatectomy.

Clinicopathologic features of incidental prostatic adenocarcinoma in radical cystoprostatectomy specimens

Background

The aim of this study is to review all features of incidentally discovered prostate adenocarcinoma in patients undergoing radical cystoprostatectomy for bladder cancer.

Methods

The medical charts of 300 male patients who underwent radical cystoprostatectomy for bladder cancer between 1997 and 2005 were retrospectively reviewed. The mean age of the patients was 62 (range 51-75) years.

Results

Prostate adenocarcinoma was present in 60 (20%) of 300 specimens. All were acinar adenocarcinoma. Of these, 40 (66.7%) were located in peripheral zone, 20 (33.3%) had pT2a tumor, 12 (20%) had pT2b tumor, 22(36.7%) had pT2c and, 6 (10%) had pT3a tumor. Gleason score was 6 or less in 48 (80%) patients. Surgical margins were negative in 54 (90%) patients, and tumor volume was less than 0.5 cc in 23 (38.3%) patients. Of the 60 incidentally detected cases of prostate adenocarcinoma 40 (66.7%) were considered clinically significant.

Conclusion

Incidentally detected prostate adenocarcinoma is frequently observed in radical cystoprostatectomy specimens. The majority are clinically significant.

Prediction of prostatic involvement by urothelial carcinoma in radical cystoprostatectomy for bladder cancer

OBJECTIVES

To ascertain which variables of bladder urothelial carcinoma (UC) might be useful in predicting either UC involving the prostate (UCP) or incidental prostate adenocarcinoma in radical cystoprostatectomy specimens.

METHODS

The bladder and whole-mount prostate sections of 248 radical cystoprostatectomy specimens were reviewed. Stepwise discriminant analysis was used to predict UCP or incidental prostate adenocarcinoma.

RESULTS

UCP was present in 94 patients (37.9%). UC originated from the prostatic urethra and periurethral ducts in 78 (31.45%), and isolated direct extension of UC from the bladder was present in 16 patients (6.45%). The periurethral ducts coexisted with direct extension of bladder UC in 11 patients (4.4%). Prostate adenocarcinoma was identified in 123 patients (49.6%). Carcinoma in situ and high-grade urothelial papillary carcinoma were seen in 8 (3.2%) and 5 (2.0%) patients, respectively. In 57 (23%), 64 (25.8%), and 87 (35.1%) patients, UC had invaded the subepithelial connective tissue, muscularis propria, and perivesical tissue, respectively. UC was multifocal in 53 patients (21.4%). The tumor was in the trigone and bladder neck in 160 patients (64.5%). Of the 248 patients, 98 (39.5%) had a history of recurrence. Stepwise discriminant analysis selected 3 variables of bladder UC (previous recurrence and location and number of foci) and correctly predicted the group in 72.2% of patients without and with UCP. Discriminant analysis selected 2 variables of bladder UC (focality and previous recurrence) and correctly predicted the group in 57.7% of patients without and with prostate adenocarcinoma.

CONCLUSIONS

Our approach can identify bladder UC variables that could guide urologists in the selection of the most appropriate surgical procedure.