Outcome of Patients with Fortuitous Prostate Cancer after Radical Cystoprostatectomy for Bladder Cancer

Incidental prostate cancer in patients who underwent radical cystectomy for high risk non muscle invasive bladder cancer: Is it clinically significant?

INTRODUCTION AND OBJECTIVE

Non muscle invasive, high-risk, bladder cancer is an entity which is usually treated with radical cystectomy. Incidental prostate cancer refers to prostate cancer detected in radical cystectomy specimens in patients with no signs of the disease. Objective of this study is to report the prevalence, characteristics, and clinical significance of incidental prostate cancer in non-muscle invasive bladder cancer patients treated with radical cystectomy in our department.

MATERIAL AND METHODS

We retrospectively reviewed data from 41 patients who underwent radical cystectomy for non-muscle invasive, high risk, bladder cancer during the years 2016-2020 in our department. Prostate cancer was described as clinically significant when there were positive surgical margins, extraprostatic extension, Gleason score >6, or tumor volume ⩾0.5 cm³. Two groups of patients were formed according to the presence or absence of clinically significant prostate cancer.

RESULTS

Incidental prostate cancer in the cystectomy specimens was detected in 21 of the 35 patients investigated. Clinically significant prostate cancer was detected in five patients. Positive surgical margins and extraprostatic extension were present in one patient, respectively. Gleason score was more than six in four of the five patients and PCa tumor volume was above 0.5 cm³ in three patients. Two patients with clinically significant prostate cancer were diagnosed with biochemical recurrence during their follow up.

CONCLUSIONS

In non-muscle invasive, high-risk patients undergoing radical cystectomy, clinically significant incidental PCa is an important issue as it may affect prognosis, quality of life, metastasis free survival, and overall survival.

Long-term outcomes of incidental prostate cancer at radical cystectomy

OBJECTIVE

We evaluated the natural history and long-term outcomes of incidentally detected prostate cancer (PCa) at radical cystectomy (RC) for bladder cancer (BCa).

PATIENTS AND METHODS

We identified 1,640 male patients who underwent RC between 1992 and 2012. Patients were stratified as clinically insignificant and clinically significant PCa, based on Grade Group (GG) 1 and ≥2, respectively. Survival was assessed using the Kaplan-Meier method.

RESULTS

There were 329 (20%) patients with incidentally detected PCa at RC: 245 (15%) GG1, 52 (3.2%) GG2, 20 (1.2%) GG3, 6 (0.4%) GG4, and 6 (0.4%) GG5. Median follow-up among survivors was 9.6 years (interquartile range 7.5-13.3), during which time 253 patients died, of whom 127 died of BCa and 1 died of PCa. Nine patients experienced biochemical recurrence (BCR), 4 underwent salvage PCa therapies, and 2 developed PCa metastases. Patients with clinically significant PCa were significantly more likely to experience BCR (6% vs. 1.6%; P = 0.04) and had shorter median time to BCR (1.8 vs. 10.4 years; P = 0.01) than those with clinically insignificant PCa. No patients with BCR had greater than pT2N0 BCa or positive BCa margins. Ten-year PCa-specific survival, BCa-specific survival, other cause-specific survival, and overall survival were 99%, 57%, 63%, and 35%, respectively.

CONCLUSIONS

In a large RC series, we note a 20% rate of incidental PCa, the majority of which are clinically insignificant. On long-term follow-up, we determined that BCR and PCa mortality are extremely rare events among these patients. Pending validation, future guidelines may consider omission of PCa surveillance for some patients with incidental PCa at RC.

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.

Using hospital medical record data to assess the accuracy of the SEER Los Angeles Cancer Surveillance Program for initial treatment of prostate cancer: a small pilot study

PURPOSE

Treatment information from the Surveillance, Epidemiology, and End Result Program (SEER) cancer registries is increasingly being used for population-based cancer research; however, it may be incomplete for outpatient procedures and is not quality controlled. We sought to validate SEER information on initial treatment of prostate cancer by comparison to electronic medical record (EMR) review.

METHODS

Patients diagnosed with prostate cancer between 1 January 2010 and 31 December 2014 in Los Angeles County who received treatment at our institution within 6 months of diagnosis were identified from the SEER registry. We reviewed the hospital EMR for these patients and identified initial treatment received within 6 months of diagnosis. We compared data reported to SEER data to our re-abstracted hospital EMR data (defined as the gold standard) to identify the completeness of SEER treatment data (sensitivity) and the accuracy of the SEER information (positive predictive value).

RESULTS

Based on 266 eligible patients, SEER's sensitivity in capturing initial treatment was 95.9% (118/123) for prostatectomy, 95.8% (69/72) for no treatment, 87.5% (21/24) for radiation therapy, 68.3% (28/41) for active surveillance or watchful waiting, and 50.0% (2/4) for cryosurgery. The SEER positive predictive value was 100% for radiation therapy and cryosurgery, 97.5% (118/121) for radical prostatectomy, 82.3% (28/34) for active surveillance or watchful waiting, and 78.4% (69/88) for no treatment.

CONCLUSION

The SEER data were highly sensitive and has a high positive predictive value for surgery and radiation therapy but underreported use of active surveillance. These results may assist researchers in understanding the strengths and weaknesses of using SEER prostate cancer treatment data.

Clinical Significance of Incidental Prostatic Carcinoma on Radical Cystectomy Histology Specimens: a Clinicopathological and Survival Analysis

Incidental prostatic carcinoma on radical cystectomy histology specimens is not an uncommon entity and managing such cases is still controversial. Classification into clinically significant and insignificant cancers by Epstein based on the assumption that one is more likely to affect the survival than the other is not universally accepted. We conducted this retrospective analysis with the aim to find out the role of dichotomization of incidental prostatic cancer into such classification. Patient's data were retrospectively reviewed from January 2013 to December 2014. A total of 175 patients underwent radical cystectomy during the study duration and amongst them, 38 specimens showed incidental prostatic cancer. Their data pertaining to demographic profile, clinicopathological details, treatment received, complications and follow-up data was recorded. On comparative analysis, the disease-free survival in csPCa (clinically significant prostatic cancer) group was 60.82% and cisPCa (clinically insignificant prostatic cancer) 62.68% at 2.3 years (p 0.566), while OS was 55.68% for csPCa and 87.5% for cisPCa respectively (p 0.814). The mean duration to recurrence was also comparable (19.4 months csPCa and 17 months cisPCa). None of the patients developed PSA elevation on follow-up and none of the recurrence or death were attributed to prostatic cancer. The stage of bladder cancer was the only factor, which had a significant impact on overall survival. The distinction between clinically significant and insignificant is not relevant according to our analysis.

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.

Incidental prostate cancer diagnosed at radical cystoprostatectomy for bladder cancer: disease-specific outcomes and survival

Background

The current standard of care for men with muscle-invasive bladder cancer is radical cystoprostatectomy (RCP). One-third of RCP specimens demonstrate incidental prostate cancer, primarily reported in small series with limited follow-up. The aim of this study is to report mature outcomes, including patterns of failure and disease-specific recurrence rates, and survival, for a large cohort of men with incidental prostate cancer at RCP performed at a tertiary referral center.

Methods

This retrospective study describes cancer control and survival rates for men who underwent RCP for bladder cancer and were found incidentally to have prostate cancer. Analysis of patient-, tumor-, and treatment-specific factors were analyzed for association with disease control and survival endpoints.

Results

Between 2002 and 2010, 94 patients with incidental discovery of prostate cancer postRCP were identified for inclusion in this study. Forty-five patients (45%) underwent RCP for recurrent (rather than initial presentation of) bladder carcinoma. At a median follow-up of 40.3 months (71.2 months for survivors; range, 8.9–155.5 months), 42 patients were alive without recurrence and 52 patients had died (25 associated with disease). The estimated 5-year bladder cancer disease-free, urinary tract malignancy disease-free, and prostate specific antigen (PSA) relapse-free survivals were 76% [95% confidence interval (CI), 65–84%], 64% (52–74%), and 97% (79–100%), respectively. The estimated 5-year urinary tract malignancy-specific and overall survivals were 61% (49–71%) and 52% (41–62%), respectively. Univariate analysis demonstrated associations between pathologic T/N-stage and nodal ratio with bladder cancer disease-free, urinary tract malignancy disease-specific, and overall survivals, with patient age at diagnosis as an additional adverse factor associated with overall survival. Multivariate analysis confirmed pN-stage and age as independently associated with worse survival.

Conclusion

For men undergoing RCP for bladder cancer, the present study suggests that incidentally discovered prostate cancers, irrespective of pathologic stage, Gleason score, or clinical significance, do not impact 5-year disease control or survival outcomes.

Oncologic aspects of long-term followed incidental prostate cancer detected by cystoprostatectomy in Korean patients

Purpose

To determine the incidence and clinical features of incidentally discovered prostate adenocarcinoma in patients undergoing radical cystoprostatectomy (CPT) for bladder cancer.

Methods

Ninety-six consecutive patients scheduled to undergo CPT were prospectively enrolled. The prostates were excised completely during CPT. The CPT specimens were examined, and the clinicopathologic characteristics of incidental prostate cancer studied. Complete transverse sections of the prostate were taken from the apex to the base at 4-mm intervals and all prostates were examined by a single pathologist.

Results

The mean patient age and prostate-specific antigen level were 66.1 ± 10.0 years and 2.8 ± 5.0 ng/mL, respectively. Of the 96 patients, 35 (36.5%) had prostate cancer (PCa). Of these incidental PCas, 57.1% (20.8% of all patients undergoing CPT) were clinically significant. None of the patients who were age ≤50 years had incidental PCa. However, the incidences of PCa in the 51–60 years, 61–70 years, and ≥71 years age groups were 27.8% (5/18), 48.7% (19/39), and 35.5% (15/31), respectively, and the difference according to the age subgroup was significant (P = 0.048). During the median follow-up of 49 months, 29.2% (28/96) of patients died. There were no PCa-specific deaths, and two patients (2.1%) showed biochemical recurrences.

Conclusion

Incidental PCas were diagnosed in ∼40% of CPT specimens, and ∼50% of incidental PCas were clinically significant. During radical CPT in patients aged ≥60 years, the possibility of the presence of PCa and the potential oncologic risk of partial prostatectomy during CPT should be remembered.

Incidental prostate cancer at the time of cystectomy: the incidence and clinicopathological features in Chinese patients

OBJECTIVES

To evaluate the incidence and the clinicopathological features of incidental prostate cancer detected in radical cystoprostatectomy (RCP) specimens in Chinese men and to estimate the oncological risk of prostate apex-sparing surgery for such patients.

METHODS

The clinical data and pathological feature of 504 patients who underwent RCP for bladder cancer from January 1999 to March 2013 were retrospectively reviewed. Whole mount serial section of the RCP specimens were cut transversely at 3-4 mm intervals and examined in same pathological institution.

RESULTS

Thirty-four out of 504 patients (6.8%) had incidental prostate cancer with a mean age of 70.3 years. 12 cases (35.2%) were diagnosed as significant disease. 4 cases were found to have apex involvement of adenocarcinoma of the prostate while in 5 cases the prostate stroma invasion by urothelial carcinoma were identified (one involved prostate apex). The mean follow-up time was 46.4±33.8 months. Biochemical recurrence occurred in 3 patients but no prostate cancer-related death during the follow-up. There was no statistical significance in cancer specific survival between the clinically significant and insignificant cancer group.

CONCLUSIONS

The prevalence of incidental prostate cancer in RCP specimens in Chinese patients was remarkably lower than in western people. Most of the incidental prostate cancer was clinically insignificant and patient's prognosis was mainly related to the bladder cancer. Sparing the prostate apex was potentially associated with a 1.0% risk of leaving significant cancer of the prostate or urothelial carcinoma.

[Prognostic influence of prostate gland invasion by bladder tumour and/or prostate cancer in cystoprostatectomy specimen: a review]

INTRODUCTION

Cystoprostatectomy (CPT) is the gold standard surgical treatment for muscle invasive bladder cancer (MIBC). In certain cases, MIBC can invade the prostate gland and/or a prostate cancer (PCa) can be discovered fortuitously on the pathologic specimen. The aim of the current study was to report the prognostic influence of PCa in patients who underwent a CPT for MIBC.

MATERIALS AND METHODS

A systematic review of the scientific literature was achieved in the Pubmed database, using the following keywords: prostatic neoplasm; urinary bladder neoplasm; cystectomy; surgery; recurrence; prognosis; survival. Clinical cases and series of less than five cases were deliberately excluded herein.

RESULTS

Overall, ten studies published between 2004 and 2011 and involving 2196 patients were selected. Only retrospective studies of low level of evidence (NP 4) were available. The incidence of neoplastic invasion of the prostate gland by MIBC ranged from 25 to 48%. Preoperative predictors were multiple BC, recurrent, location in the trigone and existence of CIS. Overall survival at 3 years was significantly affected by the invasion of the prostate gland (pT4a) in these patients. The incidence of PCa discovered incidentally pathologic specimen CPT ranged from 14 to 49%. Only age was found as a positive predictor. The diagnosis of PCa did not influence survival of patients with MIBC and no specific PCa adjuvant treatment was systematically advocated.

CONCLUSION

Fortuitous diagnosis of PCa and/or neoplastic invasion of the prostatic gland by BC on CPT specimen is not uncommon but this is variable across studies, depending on the quality of the pathological analysis. The invasion of the prostate gland by MIBC is a serious situation (pT4a) and linked with a poor prognosis. In case of concomitant PCa and MIBC, the prognosis is much more related to the natural history of the bladder tumour.

Comparison of incidentally detected prostate cancer with screen-detected prostate cancer treated by prostatectomy

BACKGROUND

The prostate may often harbor a prostate cancer (PC) which will not cause morbidity if left untreated. Screening for PC leads to increased detection of these insignificant cancers. Objective of this study is to compare PC detected by PSA screening at subsequent screening rounds and treated by radical prostatectomy (RP) with PC incidentally found in cystoprostatectomy specimens.

METHODS

Radical prostatectomy specimens of 617 screen-detected PC were compared with 123 PC identified in cystoprostatectomy specimens. Surgical specimens were systematically examined and stage, grade, tumor volume were recorded. Next, we classified PC as clinically significant or insignificant (i.e., tumor volume <0.5 cm(3), absence of Gleason pattern 4/5, organ confined). Pathological features of incidentally detected PC were compared with PC detected in subsequent screening rounds and with screen-detected T1c PC.

RESULTS

Screen-detected PC overall were more often multifocal, larger in volume, more advanced in tumor stage and of higher grade, while the frequency of insignificant PC was lower as compared to those in cystoprostatectomy specimens. This effect became more pronounced during subsequent screening rounds. Screen-detected T1c PC were also more often multifocal (73% vs. 37%) in average fivefold larger (0.85 cm(3) vs. 0.16 cm(3)), less often organ confined (81% vs. 94%), and less frequently clinically insignificant (33% vs. 81%).

CONCLUSIONS

Screen-detected (T1c) PC treated with RP shows more aggressive features than incidentally found PC. This PSA screening-related selection seems to be mainly driven by tumor volume and-in later screening rounds-by the preferential treatment by prostatectomy of more aggressive PC.

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.

Is incidentally detected prostate cancer in patients undergoing radical cystoprostatectomy clinically significant?

Cystoprostatectomy specimens obtained from patients with bladder cancer provide a unique opportunity to assess the features of silent prostate adenocarcinoma (PCa). The whole-mount prostate sections of 248 totally embedded and consecutively examined radical cystoprostatectomy (RCP) specimens were reviewed to determine the incidence and features of incidentally detected PCa. PCa was considered clinically significant if any of the following criteria were present: total tumor volume, 0.5 cc or more; Gleason grade, 4 or more; extraprostatic extension; seminal vesicle invasion; lymph node metastasis (of PCa); or positive surgical margins. PCa was present in 123 (49.6%) of 248 specimens. Features were as follows: acinar adenocarcinoma, 123 (100.0%); peripheral zone location, 98 (79.7%); pT2a, 96 (78.0%); pT2b, 11 (8.9%); pT2c, 9 (7.3%); pT3a, 5 (4.1%); pT3b, 2 (1.6%); pT4, 0 (0.0%); Gleason score 6 or less, 107 (87.0%); negative margins, 119 (96.7%); pN0 for PCa, 123 (100.0%); and tumor volume less than 0.5 cc, 116 (94.3%). Of the 123 incidentally detected cases of PCa, 100 (81.3%) were considered clinically insignificant. Incidentally detected PCa is frequently observed in RCP. The majority are clinically insignificant.

Incidental prostate cancer detected by cystoprostatectomy in Korean men

OBJECTIVES

To determine the incidence and characteristics of incidental prostate cancer diagnosed by cystoprostatectomy (CPT) in Korean men.

METHODS

Thirty-six consecutive male patients scheduled to undergo CPT were prospectively enrolled. The CPT specimens were examined and the clinicopathologic characteristics of incidental cancers compared with those of T1c prostate cancers that had undergone radical prostatectomy. Complete transverse sections of the prostate were taken from the apex to the base at 4-mm intervals.

RESULTS

Of the 36 CPT patients, 18 (50%) had incidental prostate cancer. Most of the incidental tumors were confined to the prostate gland, except in 1 patient. Tumor involvement at the prostate apex was found in 3 patients (16.7%), and Gleason scores in 3 cases were 7 to 10. Median tumor volume was 0.08 cm(3) (range, 0.01 to 20.51 cm(3)), and a tumor volume of more than 0.5 cm(3) was identified in 5 patients. Of these incidental prostate cancers, 38.9% (19.4% of all CPT patients) were clinically significant. As compared with the 38 T1c prostate cancer patients, incidental prostate cancer patients were older, had a lower prostate-specific antigen level, a lower grade, smaller tumor volume, and were less likely to have multiple tumors. However, no significant differences were observed between these two groups with respect to apical tumor involvement or tumor confinement to the prostate (P >0.05 for each).

CONCLUSIONS

Incidental prostate cancers were diagnosed in 50% of CPT specimens, and 19.4% of these were clinically significant.

Clinicopathologic Features of Prostate Adenocarcinoma Incidentally Discovered at the Time of Radical Cystectomy: An Evidence-Based Analysis

OBJECTIVES

To review all relevant features of incidentally discovered prostate cancer (PCa) in patients undergoing radical cystectomy for bladder cancer: incidence, pathologic characteristics, clinical significance, and implications for its management.

METHODS

A structured literature review through a MEDLINE search was performed.

RESULTS

The frequency of incidentally discovered PCa in cystoprostatectomy specimens is extremely variable because of several factors, particularly the pathology sampling. The relationship among clinically, incidentally, and autopsy-detected cancer is uncertain. The definition of clinically significant cancer varies among published reports and remains inadequate for clinical application. High-grade prostatic intraepithelial neoplasia is a marker for concurrent PCa and the risk depends more on the volume than on its absolute presence. Outcome of patients with unsuspected PCa after cystoprostatectomy relies mostly on the bladder tumor.

CONCLUSIONS

Incidental PCa in patients with bladder cancer is highly variable and with an unclear clinical significance. For those who are candidates for prostate-sparing surgery, it seems reasonable to include a routine prostate biopsy in the standard preoperative work-up irrespective of prostate-specific antigen values. In the absence of sufficient data to make firm recommendations, when PCa is incidentally discovered, PCa surveillance should be part of the follow-up scheme after radical cystectomy.

Characteristics of incidental prostatic adenocarcinoma in contemporary radical cystoprostatectomy specimens

OBJECTIVES

To investigate the relationship between prostate-specific antigen (PSA) level and tumour volume for incidental adenocarcinoma of the prostate found in cystoprostatectomy (CP) specimens, and to analyse the incidence of clinically significant prostate cancers in CP specimens and the biochemical recurrence of incidental prostate cancers on short-term follow up.

PATIENTS AND METHODS

Complete data from 97 of 105 prostates from CP specimens were available. Prostates were thoroughly analysed and sectioned at 2 mm intervals. PSA levels and the findings at digital rectal examination before surgery were obtained prospectively. None of the patients had any evidence of prostate cancer before CP.

RESULTS

Incidental prostate cancer was detected in 58 of 97 (60%) of the CP specimens; of these, 31 (53%) were significant according to the definition of Stamey et al. There was a weak correlation between tumour volume and PSA level, weighted solely by the four larger-volume cancers. The median PSA level for patients with and without prostate cancer was not significantly different (3.1 vs 1.1 ng/mL, P = 0.06). The follow-up of the 35 patients alive with prostate cancer showed four PSA recurrences (PSA >0.02 ng/mL) with one distant metastasis after a median follow-up of 3 years. None of the patients with insignificant tumours developed biochemical recurrence.

CONCLUSIONS

The weak correlation between PSA level and tumour volume in these patients supports the argument that PSA is largely produced by benign prostatic hyperplasia and is therefore a poor screening tool for asymptomatic healthy men. Most incidental prostate cancers in CP specimens are significant, contrary to previous analyses, but have little practical importance in terms of oncological outcome.

HER2 expression and gene amplification in pT2a Gleason score 6 prostate cancer incidentally detected in cystoprostatectomies: comparison with clinically detected androgen-dependent and androgen-independent cancer

Previous studies have demonstrated HER2 protein overexpression and/or gene amplification in a subset of patients with clinically significant prostate cancer (PCa), especially in the androgen-independent phase of the disease. There are no studies on incidentally detected PCa. The aim of the study was to analyze HER2 expression and gene amplification in PCa incidentally detected in cystoprostatectomies. High-grade prostatic intraepithelial neoplasia (HGPIN) was also investigated. Comparison was made with clinically detected PCa, both untreated and hormonally treated, and with androgen-independent PCa. Nineteen cystoprostatectomy (CyP) and 44 radical prostatectomy specimens (25 untreated and 19 hormonally treated) with pT2a Gleason score 6 cancer and HGPIN were used in this study. It also included 9 specimens of transurethral resection of the prostate with hormone-independent cancer and 8 cases of normal prostate tissue from CyP specimens without PCa and prostatic intraepithelial neoplasia. HER2 protein and Ki-67 were investigated immunohistochemically. Patients with immunohistochemical scores of 2+ and 3+ were considered to have HER2 overexpression (HercepTest method). Dual-color fluorescence in situ hybridization analysis was performed using the CEP-17/HER dual probe combination. High-grade prostatic intraepithelial neoplasia showed HER2 overexpression in 26% of the CyP cases and in 40% and 83% of the untreated and treated cases, respectively. Prostate cancer showed HER2 overexpression in 16% of cases in the CyP group and in 36% and 47.5% in the untreated and treated groups, respectively. HER2 overexpression was present in 78% of androgen-independent cancers. HER2 gene amplification was seen in a small proportion of nuclei and some of the cases. In HGPIN, it ranged from 1.1% (in 5 cases) in the CyP group to 2.1% (in 10 cases) and 1.9% (in 6 cases) in the untreated and treated groups, respectively. In PCa, the proportion of nuclei with gene amplification was 0.7% (in 3 cases) in the CyP group, 2.6% (in 10 cases) and 2.5% (in 12 cases) in the untreated and treated groups, respectively, and 9% (in 6 cases) in the androgen-independent PCa. Ki-67 expression in HGPIN and PCa in CyP specimens was lower than in the radical prostatectomies and cases of transurethral resection of the prostate. Our findings in the current HER2-related study indicate that incidentally detected cancer has features of less aggressiveness than clinically detected cancer. This may contribute to a better understanding of the results obtained in screening programs where insignificant cancers are detected along with clinically significant cancers.