Search for residual prostate cancer on pT0 radical prostatectomy after positive biopsy

Prostate-Specific Membrane Antigen Is a Biomarker for Residual Disease following Neoadjuvant Intense Androgen Deprivation Therapy in Prostate Cancer

PURPOSE

Neoadjuvant intense androgen deprivation therapy (iADT) can exert a wide range of histological responses, which in turn are reflected in the final prostatectomy specimen. Accurate identification and measurement of residual tumor volumes are critical for tracking and stratifying patient outcomes.

MATERIALS AND METHODS

The goal of this current study was to evaluate the ability of antibodies against prostate-specific membrane antigen (PSMA) to specifically detect residual tumor in a cohort of 35 patients treated with iADT plus enzalutamide for 6 months prior to radical prostatectomy.

RESULTS

Residual carcinoma was detected in 31 patients, and PSMA reacted positively with tumor in all cases. PSMA staining was 96% sensitive for tumor, with approximately 82% of benign regions showing no reactivity. By contrast, PSMA positively reacted with 72% of benign regions in a control cohort of 37 untreated cases, resulting in 28% specificity for tumor. PSMA further identified highly dedifferentiated prostate carcinomas including tumors with evidence of neuroendocrine differentiation.

CONCLUSIONS

We propose that anti-PSMA immunostaining be a standardized marker for identifying residual cancer in the setting of iADT.

Added Clinical Value of Whole-mount Histopathology of Radical Prostatectomy Specimens: A Collaborative Review

CONTEXT

Whole-mount histopathology, that is, large format histology or whole-mount sectioning, refers to the histopathological examination of tissue sections from specimens processed with large tissue cassette. In some institutions, it is applied routinely to specimens with genitourinary cancers.

OBJECTIVE

To give an overview of the application of the large format histology to the morphological examination of the radical prostatectomy (RP) specimens.

EVIDENCE ACQUISITION

A comprehensive PubMed search was performed up to May 2020, using the keywords "prostate carcinoma," "radical prostatectomy specimens," "whole-mount histopathology," "whole mount sectioning," "large format histology," "macrosectioning," "diagnostic criteria," and "prognosis." The search, supplemented with a hand search, was restricted to articles published in the English language. No limitations were placed on the publication year. References in relevant articles were also reviewed.

EVIDENCE SYNTHESIS

Even though the whole-mount sections of RPs appear not to be superior to regular sections in detecting adverse pathological features, their use has the advantage of displaying the architecture of the prostate gland and identifying and locating tumor nodule(s) more clearly, with particular reference to the index tumor. Further, it is easier to compare the pathological features with clinical findings derived, for instance, from digital rectal examination, transrectal ultrasound, multiparametric magnetic resonance imaging, surgical operation, and prostate biopsies.

CONCLUSIONS

Urologists, radiologists, and oncologists are updated about the step forward made by pathologists when diagnostic and prognostic information is derived from an approach that closely resembles that used by the clinicians when dealing with imaging findings.

PATIENT SUMMARY

Adoption of the whole-mount histopathology adds clinical value in correlation with clinical/imaging findings of radical prostatectomy specimens.

Contemporary clinicopathological characteristics of pT0 prostate cancer at radical prostatectomy: A population-based study

BACKGROUND

The incidence of pT0 prostate cancer (CaP) at radical prostatectomy (RP) is extremely rare. We performed the first population-based analysis of pT0 CaP at RP.

METHODS

Within the Surveillance, Epidemiology, and End Results database (2004-2015), we tested for clinical and pathological characteristics according to pT0 vs. non-pT0 CaP and included a multivariable logistic regression model.

RESULTS

pT0 was identified in 358 (0.2%) out of 160,532 clinically localized RP patients. The majority of pT0 patients presented with initial prostate-specific antigen (PSA) <10 ng/ml (82.4%), harboured biopsy Gleason score (GS) 6 (69.8%) and cT1 disease (78.1%). Nonetheless, pT0 was identified in 13 (3.6%) patients with PSA ≥20 ng/ml, in 69 (19.3%) patients with biopsy GS ≥7 and in 78 (21.8%) patients with ≥cT2 disease. In a subset of patients with available number of biopsy cores, pT0 was identified in 34 (33.3%) patients with ≥2 positive biopsy cores. Age, race, marital status, hospital region, population density, PSA, as well as number of biopsy cores did not discriminate between pT0 and non-pT0 cases. Analyses according to annual rates (2004-2015) of pT0 did not vary between the years (0.2%-1.6%, estimated annual percent change: -1.6%, P = 0.3). Neither did the rates vary according to geographic region.

CONCLUSIONS

pT0 at RP is very rare. Even though, most pT0 patients have low PSA, low clinical stage, low biopsy GS, and only one positive biopsy core, those with more aggressive characteristics can still harbour pT0 at RP.

Effect of Neoadjuvant Hormone Therapy on Resection Margin and Survival Prognoses in Locally Advanced Prostate Cancer after Prostatectomy Using Propensity-Score Matching

This study aimed to investigate the effect of neoadjuvant hormone therapy (NHT) on resection margin positivity, biochemical-recurrence- (BCR-) free survival, and overall survival (OS) in 176 patients with locally advanced prostate cancer (LAPC) treated with radical prostatectomy using propensity-score matching, including 79 (44.9%) patients treated with the NHT. Fifty pairs of one-to-one propensity-score matching were matched to investigate the pure effect of NHT on resection margin positivity, BCR, and OS with a statistical significance of p<0.050. Before matching, NHT, tumor volume percentage, and extracapsular extension were significant factors for resection margin positivity (p≤0.001); however, after matching, NHT became insignificant in the multivariate analysis (p=0.084). In the survival analysis, NHT was not associated with BCR or OS before and after matching (BCR: hazard ratio, 1.35 and 0.84, respectively; OS: hazard ratio, 1.05 and 0.77, respectively; p≥0.539 for all). Conversely, PSA level (HR, 2.23), extracapsular extension (HR, 2.10), and lymphovascular invasion (HR, 1.85) were significant factors for BCR (p≤0.001 for all), but none were significant factors for OS in the propensity-score matching analysis (p≥0.948). Therefore, NHT was not a significant factor for resection margin positivity, BCR-free survival, and OS before and after propensity-score matching in patients with LAPC.

The prevalence and outcomes of pT0 disease after neoadjuvant hormonal therapy and radical prostatectomy in high-risk prostate cancer

Background

To identify the prevalence and clinical outcomes of pT0 disease following neoadjuvant hormonal therapy (NHT) and radical prostatectomy (RP) in high-risk prostate cancer.

Methods

We retrospectively included 111 patients who had received NHT and RP for the treatment of high-risk prostate cancer. We classified the patients into two groups, the pT0 group and the non-pT0 group, depending on whether a residual tumor was observed.

Results

We identified 6 cases (5.4 %) with pT0 disease after reviewing the slides of all patients. There was no recurrence of disease in the pT0 group during a median follow-up of 59 months. Among the 105 patients in the non-pT0 group, biochemical recurrence (BCR) developed in 60 patients (57.1 %), with the median time to BCR being 14 months.

Conclusions

Among the 111 patients with high-risk prostate cancer, we found 6 cases that showed a complete pathological response after NHT and no recurrence of disease during the follow-up, meaning that the androgen deprivation therapy could potentially eradicate high-risk prostate cancer. This is one of the largest studies demonstrating the prevalence of pT0 disease and its outcomes after NHT among patients with high-risk prostate cancer.

DNA comparison between operative and biopsy specimens to investigate stage pT0 after radical prostatectomy

PURPOSE

The aim was to eliminate, by DNA comparison, any identity mismatch between operative and biopsy specimens and to analyse the determinants of all pT0 prostate cancers occurred in a single institution.

METHODS

All prostate pT0 cases in a single institution over 20 years were investigated. None of the patients had been diagnosed after a transurethral resection of the prostate nor had they received neoadjuvant hormonal treatment. The biopsies performed in other centres had been referred for a centralized pathologic re-analysis. DNA analysis was performed in samples from operative and biopsy specimens, and pairs of tissues were blindly constituted. Correct matching was verified in each pair and compared to the original database in order to comment on the occurrence of identity mismatches in the series.

RESULTS

Nineteen patients (0.77 %) had been diagnosed as having pT0 prostate cancer among the 2,462 RP procedures performed over 19 years. The biopsy re-analysis invalidated the initial diagnosis of prostate cancer in one biopsy set performed elsewhere. Among 12 entirely processed cases, the biochemistry procedure evaluated as "very unlikely" the occurrence of an error in tissue identification in the biopsy setting, during the surgical procedure or the pathological analysis. No identification error of tissue samples was established in this first verified pT0 series.

CONCLUSIONS

Although it must be suspected, specimen identification error was not a cause for pT0 prostate cancer. Only after a full pathological and DNA verification, the pT0 stage remains a sole entity, unexplained in most cases.

pT0 Prostate Cancer: Predictive Clinicopathologic Features in an American Population

INTRODUCTION

The pT0 stage of prostate cancer describes the radical prostatectomy (RP) specimen where no cancer can be identified. Given known racial and geographic differences in prostate cancer incidence and survival, we reviewed our experience with pT0 disease to determine applicability of these predictive features in an American population.

MATERIALS AND METHODS

A retrospective chart review was conducted for all RPs at one state tertiary care institution during a 20-year period (1991-2011). Clinicopathologic features of pT0 patients were collected and their relevant pathologic material re-reviewed.

RESULTS

Of a total of 1,635 RPs performed, 4 (0.2%) not receiving neoadjuvant therapy or other prior prostate surgeries were stage pT0. Biopsies from 3 of 4 patients were re-evaluated and confirmed a small focus, <1% of tissue, of Gleason score 3+3 adenocarcinoma; a fourth was not available for re-review. Our re-review of the RP slides identified small foci of cancer in two of the four, thus yielding a final true pT0 incidence of 0.1%. Preoperative prostate specific antigen ranged from 4.4 to 7.4 ng/ml, clinical stages were all T1c, and there was no evidence of recurrence at 3 months to 10 years of follow-up.

CONCLUSIONS

Stage pT0 prostate cancer is very uncommon, occurring with an incidence of 0.1%, and in our experience occurs only in clinical T1c patients with pre-biopsy prostate specific antigen < 7.5 ng/ml, with Gleason score 3 + 3 adenocarcinoma comprising < 1%, 1 mm of a single core biopsy, a stricter threshold than that seen in non-American populations.

[Status and medicolegal implications in France pT0 stage of prostate cancer: a study by the CC-AFU]

OBJECTIVE

To assess the frequency, circumstances, and possible medico-legal consequences of the pT0 prostate cancer, defined by the absence of tumor in a radical prostatectomy specimen.

METHODS

Six centers retrospectively identified all cases of pT0 and selectionned those that occurred without prior hormone therapy or prostate resection. Preoperative data, histological report and clinical and biological outcome were analyzed. The lawsuits' registry in pathology were consulted at insurance companies.

RESULTS

Thirty cases of pT0 prostate cancer (0.4%) were reported on 7693 patients. The median age was 63years, PSA 7.4ng/mL. The number of positive preoperative biopsies ranged from one to four for a median tumor length of 1mm (0.3 to 18mm). The biopsy Gleason score was 3+3 for 23 patients, less than 5 for six others and included a contingent of grade 4 in two patients. With a median follow-up of 82months, no clinical or biochemical recurrence was observed. One patient complaint for pT0 prostate was found in the insurances registry.

CONCLUSION

The occurrence of a prostate pT0 called into question all the diagnostic procedures and surgical indication. To avoid a forensic procedure, urologists should inform patients of the possibility of this situation before radical prostatectomy.

Trends in prostatic adenocarcinoma tumor volume by visual estimation in prostatectomy specimens

We retrospectively reviewed 1792 consecutive radical prostatectomies (RP) from 2003 to 2006 at a single institution to establish tumor volume reference values, to determine current trends in visually estimated prostate adenocarcinoma tumor volume, and to characterize cases with no residual cancer on RP. Tumor volumes were recorded and subsequently stratified as very low, 0-1%; low, 1.1-10%; intermediate, 10.1-20%; high, 20.1-50%; and very high, >50%, with incidences of 11.7%, 52.1%, 21.5%, 13.2%, and 1.5%, respectively. The incidence of very low volume tumors increased within the time period (p=0.04). Seminal vesicle involvement was detected in 5.0% of cases and lymph node metastasis occurred in 1.4%. Volume categories statistically correlated with seminal vesicle invasion (p=0) and lymph nodes metastases (p=0). Eleven cases of no residual cancer (0.6%) were identified with a non-statically significant increase during the study (p=0.07). The rising incidence of very low volume tumors should be considered by clinicians when discussing treatment options with patients. A discrete tumor volume should be provided for RP specimens as it may be an important prognostic factor.

Handling of radical prostatectomy specimens: total embedding with large-format histology

A problem when handling radical prostatectomy specimens (RPS) is that cancer is often not visible at gross examination, and the tumor extent is always underestimated by the naked eye. The challenge is increased further by the fact that prostate cancer is a notoriously multifocal and heterogeneous tumor. For the pathologist, the safest method to avoid undersampling of cancer is evidently that the entire prostate is submitted. Even though whole mounts of sections from RPS appear not to be superior to sections from standard blocks in detecting adverse pathological features, their use has the great advantage of displaying the architecture of the prostate and the identification and location of tumour nodules more clearly, with particular reference to the index tumour; further, it is easier to compare the pathological findings with those obtained from digital rectal examination (DRE), transrectal ultrasound (TRUS), and prostate biopsies. We are in favour of complete sampling of the RPS examined with the whole mount technique. There are reasons in favour and a few drawbacks. Its implementation does not require an additional amount of work from the technicians' side. It gives further clinical significance to our work of uropathologists.

Prediction of pathological and oncological outcomes based on extended prostate biopsy results in patients with prostate cancer receiving radical prostatectomy: a single institution study

Background

The prediction of pathological outcomes prior to surgery remains a challenging problem for the appropriate surgical indication of prostate cancer. This study was performed to identify preoperative values predictive of pathological and oncological outcomes based on standardized extended prostate biopsies with core histological results diagrammed/mapped in patients receiving radical prostatectomy for prostate cancer clinically diagnosed as localized or locally advanced disease.

Methods

In 124 patients with clinically localized or locally advanced prostate cancer (cT1c–cT3a) without prior treatment, pathological outcomes on the surgical specimen including seminal vesicle involvement (SVI), positive surgical margin (PSM), and perineural invasion (PNI) were studied in comparison with clinical parameters based on the results of 14-core prostate biopsies comprising sextant, laterally-directed sextant, and bilateral transition zone (TZ) sampling.

Results

Concerning the association of pathological outcomes with oncological outcomes, patients with PSM and PNI on surgical specimens had poorer biochemical-progression-free survival than those without PSM (logrank p = 0.002) and PNI (p = 0.003); it was also poorer concerning SVI, although the difference was not significant (p = 0.120). Concerning the impact of clinical parameters on these pathological outcomes, positive TZ and multiple positive biopsy cores in the prostatic middle were independent values predictive of SVI with multivariate analyses (p = 0.020 and p = 0.025, respectively); both positive TZ and multiple positive prostatic middle biopsies were associated with larger tumor volume (p < 0.001 in both). The percentage of positive biopsy cores (%positive cores) and biopsy Gleason score were independent values predictive of PSM (p = 0.001) and PNI (p = 0.001), respectively. Multiple positive cores in the prostatic base were associated with proximal/bladder-side PSM (p < 0.001), and also linked to poorer biochemical-progression-free survival (p = 0.004). Clinical T stage had no association with these pathological outcomes.

Conclusions

%positive cores and Gleason score in extended biopsies were independent values predictive of PSM and PNI in prostate cancer clinically diagnosed as localized or locally advanced disease, respectively, which were associated with poorer oncological outcomes. When diagramming biopsy-core results, extended biopsy may provide additional information for predicting oncological and pathological outcomes including SVI in patients clinically diagnosed as having localized or locally advanced disease.

Virtual slides

The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/8790262771042628

[Nondetectable prostate cancer in radical prostatectomy specimens]

Since the widespread use of prostate-specific antigen, early diagnosis of prostate cancer at an early stage has been increased. Consequently, a greater frequency of low-volume disease or no tumor has been found in radical prostatectomy specimen.

AIMS

In the present study authors analyzed patients classified as pT0 after radical prostatectomy at their center.

METHODS

1134 radical prostatectomies were evaluated retrospectively at the author's center between 1996 and 2010. If there was no evidence of prostate cancer in the specimen, patient was staged as pT0. Patients were divided into two groups: received neoadjuvant hormonal therapy or not.

RESULTS

Overall 32 (2.8%) patients were staged as pT0. The rate of pT0 staging was 9.3% and 1.2% in the hormonally treated group and non-hormonally treated group. False-positive prostate biopsy was found in 2 cases. The rate of pT0 staging was higher in patients with incidental prostate cancer, low Gleason score and enlarged prostate. Biochemical relapse was observed in 3 pT0 patients in the hormonally treated group, among them there was one clinical relapse. In non-hormonally treated group no recurrence was detected.

CONCLUSION

The rate of pT0 staging was higher in the hormonally treated group. Because of biochemical and clinical relapse despite vanishing prostate cancer phenomenon, these cases are considered not to be true pT0. On the basis of present study and other reports the rate of pT0 staging is about one percentage in non-hormonally treated patients. Prognosis of these patients is excellent.

Minimal or No Residual Prostatic Adenocarcinoma on Radical Prostatectomy: A 5-Year Experience With “Vanishing Carcinoma Phenomenon”

Context.—“Vanishing carcinoma phenomenon” (VC) has been defined as the finding of minute or no cancer on radical prostatectomy specimens after a positive biopsy.

Objective.—To discuss our experience with VC and to recommend guidelines for its detection.

Design.—One thousand seven hundred forty-one radical prostatectomy specimens (2004–2009) processed by whole-mount section procedure yielded 21 (1.2%) cases with VC and 6 (0.34%) cases with minimal carcinoma (≤2 mm) in the radical prostatectomy specimen. To find the eluding carcinoma in VC cases or more carcinoma in minimal carcinoma cases, the following was done: 3 levels of all the paraffin blocks were obtained; if negative, the paraffin blocks were melted, the tissue was flipped, and 3 levels were prepared. The tumor bank frozen tissue was also processed for routine examination.

Results.—Three deeper levels in the radical prostatectomy specimen of 21 VC cases failed to show malignancy; however, the flipping and recutting of the tissue yielded a focus of carcinoma (1–5 mm) in 16 of 21 cases and in 3 of 16 cases in the saved frozen tissue. In 1 of the 6 cases with minimal carcinoma, subsequent recuts of the flipped tissue displayed carcinoma (2 foci of tumor, &lt;1 mm each).

Conclusions.—In VC we recommend: embed and process any remaining prostatic tissue including any saved fresh-frozen tissue; obtain 3 levels of each paraffin block; if results are negative, melt and flip the tissue and obtain 3 more levels. Following the above guidelines, a hidden carcinoma may be detected in the majority of the cases of VC.

Biopsy misidentification identified by DNA profiling in a large multicenter trial

PURPOSE

The Reduction by Dutasteride of Prostate Cancer Events (REDUCE) prostate cancer risk reduction study randomly assigned 8,231 men to dutasteride or placebo for 4 years. Protocol-mandated biopsies were obtained after 2 and 4 years. After the discovery of three cases of biopsy sample misidentification in the first 2 years, all protocol-mandated biopsy samples were DNA tested to verify biopsy identity.

METHODS

Biopsy and blood DNA profiling was performed retrospectively for the year 2 scheduled biopsies and prospectively for the year 4 scheduled biopsies. Toward the end of year 2, multiple changes were made to improve sample handling and chain of custody.

RESULTS

Of the 6,458 year 2 and 4,777 year 4 biopsies, 26 biopsies reflecting 13 sample handling errors at year 2 (0.4%) and one biopsy reflecting one sample handling error at year 4 (0.02%) were confirmed to be mismatched to the patient for whom they were originally submitted. Of 6,733 reference blood samples profiled, 31 (0.5%) were found to be mismatched to the patient's verified identity profile. Sample identification errors occurred at local research sites and central laboratories.

CONCLUSION

Biopsy misidentification is a potential problem in clinical laboratories and clinical trials. Until now, biopsy misidentification has not been studied in the setting of a large, multinational clinical trial. In the REDUCE study, process improvement initiatives halfway through the trial dramatically reduced biopsy mismatches. The potential for biopsy mismatches in clinical trials and clinical practice is an under-recognized problem that requires rigorous attention to details of chain of custody and consideration of more widespread DNA identity testing.

International Society of Urological Pathology (ISUP) Consensus Conference on Handling and Staging of Radical Prostatectomy Specimens. Working group 1: specimen handling

The 2009 International Society of Urological Pathology Consensus Conference in Boston made recommendations regarding the standardization of pathology reporting of radical prostatectomy specimens. Issues relating to the handling and processing of radical prostatectomy specimens were coordinated by working group 1. Most uropathologists followed similar procedures for fixation of radical prostatectomy specimens, with 51% of respondents transporting tissue in formalin. There was also consensus that the prostate weight without the seminal vesicles should be recorded. There was consensus that the surface of the prostate should be painted. It was agreed that both the prostate apex and base should be examined by the cone method with sagittal sectioning of the tissue sample. There was consensus that the gland should be fully fixed before sectioning. Both partial and complete embedding of prostates was considered to be acceptable as long as the method of partial embedding is stated. No consensus was determined regarding the necessity of weighing and measuring the length of the seminal vesicles, the preparation of whole mounts rather than standardized blocks and the methodology for sampling of fresh tissue for research purposes, and it was agreed that these should be left to the discretion of the working pathologist.

Cancer biomarker discovery: the entropic hallmark

Background

It is a commonly accepted belief that cancer cells modify their transcriptional state during the progression of the disease. We propose that the progression of cancer cells towards malignant phenotypes can be efficiently tracked using high-throughput technologies that follow the gradual changes observed in the gene expression profiles by employing Shannon's mathematical theory of communication. Methods based on Information Theory can then quantify the divergence of cancer cells' transcriptional profiles from those of normally appearing cells of the originating tissues. The relevance of the proposed methods can be evaluated using microarray datasets available in the public domain but the method is in principle applicable to other high-throughput methods.

Methodology/Principal Findings

Using melanoma and prostate cancer datasets we illustrate how it is possible to employ Shannon Entropy and the Jensen-Shannon divergence to trace the transcriptional changes progression of the disease. We establish how the variations of these two measures correlate with established biomarkers of cancer progression. The Information Theory measures allow us to identify novel biomarkers for both progressive and relatively more sudden transcriptional changes leading to malignant phenotypes. At the same time, the methodology was able to validate a large number of genes and processes that seem to be implicated in the progression of melanoma and prostate cancer.

Conclusions/Significance

We thus present a quantitative guiding rule, a new unifying hallmark of cancer: the cancer cell's transcriptome changes lead to measurable observed transitions of Normalized Shannon Entropy values (as measured by high-througput technologies). At the same time, tumor cells increment their divergence from the normal tissue profile increasing their disorder via creation of states that we might not directly measure. This unifying hallmark allows, via the the Jensen-Shannon divergence, to identify the arrow of time of the processes from the gene expression profiles, and helps to map the phenotypical and molecular hallmarks of specific cancer subtypes. The deep mathematical basis of the approach allows us to suggest that this principle is, hopefully, of general applicability for other diseases.