Evidence of Perineural Invasion on Prostate Biopsy Specimen and Survival After Radical Prostatectomy

Topline/Final Diagnostic Inclusion of Relevant Histologic Findings in Surgical Pathology Reporting of Carcinoma in Prostate Biopsies

INTRODUCTION

As the list of histologic parameters to include in surgical pathology reports of prostate cancer biopsies grows, some pathologists include this information in the microscopic description or summary sections of the report, whereas others include it in the "topline" or final diagnosis section. This prompted us to develop a multi-institutional survey to assess reporting trends among genitourinary (GU) pathologists.

METHODS

A survey instrument was shared among 110 GU pathologists via surveymonkey.com. Anonymized respondent data was analyzed.

RESULTS

Eighty-four (76%) participants completed the survey across four continents. Most participants report tumor volume quantitation (88%), number of cores involved (89%), and both Gleason grade and Grade group (93%) in their topline; 71% include percent of pattern 4, with another 16% including it depending on cancer grade; 58% include the presence of cribriform growth pattern 4, with another 11% including it depending on cancer grade. When present, most include extraprostatic extension (90%), prostatic intraductal carcinoma (77%), and perineural invasion (77%). Inclusion of atypical intraductal proliferation (AIP) in the topline diagnosis was cancer grade-dependent, with 74% including AIP in Grade group 1, 61% in Grade group 2, 45% in Grade group 3, 30% in Grade group 4, and 26% in Grade group 5 cancers.

CONCLUSION

Certain histologic features such as Gleason grade and tumor volume/cores involved are frequently included in the topline diagnosis, whereas the incorporation of other findings are more variably included. Prostate biopsy reporting remains a dynamic process with stylistic similarities and differences existing among GU pathologists.

Integrative analysis of the ST6GALNAC family identifies GATA2-upregulated ST6GALNAC5 as an adverse prognostic biomarker promoting prostate cancer cell invasion

BACKGROUND

ST6GALNAC family members function as sialyltransferases and have been implicated in cancer progression. However, their aberrant expression levels, prognostic values and specific roles in metastatic prostate cancer (PCa) remain largely unclear.

METHODS

Two independent public datasets (TCGA-PRAD and GSE21032), containing 648 PCa samples in total, were employed to comprehensively examine the mRNA expression changes of ST6GALNAC family members in PCa, as well as their associations with clinicopathological parameters and prognosis. The dysregulation of ST6GALNAC5 was further validated in a mouse PCa model and human PCa samples from our cohort (n = 64) by immunohistochemistry (IHC). Gene Set Enrichment Analysis, Gene Ontology, Kyoto Encyclopedia of Genes and Genomes and drug sensitivity analyses were performed to enrich the biological processes most related to ST6GALNAC5. Sulforhodamine B, transwell, luciferase reporter and chromatin immunoprecipitation (ChIP) assays were used to examine the PCa cell proliferation, invasion and transcriptional regulation, respectively.

RESULTS

Systematical investigation of six ST6GALNAC family members in public datasets revealed that ST6GALNAC5 was the only gene consistently and significantly upregulated in metastatic PCa, and ST6GALNAC5 overexpression was also positively associated with Gleason score and predicted poor prognosis in PCa patients. IHC results showed that (1) ST6GALNAC5 protein expression was increased in prostatic intraepithelial neoplasia and further elevated in PCa from a PbCre;Pten^F/F mouse model; (2) overexpressed ST6GALNAC5 protein was confirmed in human PCa samples comparing with benign prostatic hyperplasia samples from our cohort (p < 0.001); (3) ST6GALNAC5 overexpression was significantly correlated with perineural invasion of PCa. Moreover, we first found transcription factor GATA2 positively and directly regulated ST6GALNAC5 expression at transcriptional level. ST6GALNAC5 overexpression could partially reverse GATA2-depletion-induced inhibition of PCa cell invasion. The GATA2-ST6GALNAC5 signature exhibited better prediction on the poor prognosis in PCa patients than GATA2 or ST6GALNAC5 alone.

CONCLUSIONS

Our results indicated that GATA2-upregulated ST6GALNAC5 might serve as an adverse prognostic biomarker promoting prostate cancer cell invasion.

Incidence and Predicting Factors of Histopathological Features at Robot-Assisted Radical Prostatectomy in the mpMRI Era: Results of a Single Tertiary Referral Center

Background and Objectives: To describe the predictors of cribriform variant status and perineural invasion (PNI) in robot-assisted radical prostatectomy (RARP) histology. To define the rates of upgrading between biopsy specimens and final histology and their possible predictive factors in prostate cancer (PCa) patients undergoing RARP. Material and Methods: Within our institutional database, 265 PCa patients who underwent prostate biopsies and consecutive RARP at our center were enrolled (2018-2022). In the overall population, two independent multivariable logistic regression models (LRMs) predicting the presence of PNI or cribriform variant status at RARP were performed. In low- and intermediate-risk PCa patients according to D'Amico risk classification, three independent multivariable LRMs were fitted to predict upgrading. Results: Of all, 30.9% were low-risk, 18.9% were intermediate-risk and 50.2% were high-risk PCa patients. In the overall population, the rates of the cribriform variant and PNI at RARP were 55.8% and 71.1%, respectively. After multivariable LRMs predicting PNI, total tumor length in biopsy cores (>24 mm [OR: 2.37, p-value = 0.03], relative to <24 mm) was an independent predictor. After multivariable LRMs predicting cribriform variant status, PIRADS (3 [OR:15.37], 4 [OR: 13.57] or 5 [OR: 16.51] relative to PIRADS 2, all p = 0.01) and total tumor length in biopsy cores (>24 mm [OR: 2.47, p = 0.01], relative to <24 mm) were independent predicting factors. In low- and intermediate-risk PCa patients, the rate of upgrading was 74.4% and 78.0%, respectively. After multivariable LRMs predicting upgrading, PIRADS (PIRADS 3 [OR: 7.01], 4 [OR: 16.98] or 5 [OR: 20.96] relative to PIRADS 2, all p = 0.01) was an independent predicting factor. Conclusions: RARP represents a tailored and risk-adapted treatment strategy for PCa patients. The indication of RP progressively migrates to high-risk PCa after a pre-operative assessment. Specifically, the PIRADS score at mpMRI should guide the decision-making process of urologists for PCa patients.

Predicting Tumor Perineural Invasion Status in High-Grade Prostate Cancer Based on a Clinical-Radiomics Model Incorporating T2-Weighted and Diffusion-Weighted Magnetic Resonance Images

PURPOSE

To explore the role of bi-parametric MRI radiomics features in identifying PNI in high-grade PCa and to further develop a combined nomogram with clinical information.

METHODS

183 high-grade PCa patients were included in this retrospective study. Tumor regions of interest (ROIs) were manually delineated on T2WI and DWI images. Radiomics features were extracted from lesion area segmented images obtained. Univariate logistic regression analysis and the least absolute shrinkage and selection operator (LASSO) method were used for feature selection. A clinical model, a radiomics model, and a combined model were developed to predict PNI positive. Predictive performance was estimated using receiver operating characteristic (ROC) curves, calibration curves, and decision curves.

RESULTS

The differential diagnostic efficiency of the clinical model had no statistical difference compared with the radiomics model (area under the curve (AUC) values were 0.766 and 0.823 in the train and test group, respectively). The radiomics model showed better discrimination in both the train cohort and test cohort (train AUC: 0.879 and test AUC: 0.908) than each subcategory image (T2WI train AUC: 0.813 and test AUC: 0.827; DWI train AUC: 0.749 and test AUC: 0.734). The discrimination efficiency improved when combining the radiomics and clinical models (train AUC: 0.906 and test AUC: 0.947).

CONCLUSION

The model including radiomics signatures and clinical factors can accurately predict PNI positive in high-grade PCa patients.

The Role of Perineural Invasion in Prostate Cancer and Its Prognostic Significance

Simple Summary

Prostate cancer is one of the most frequently diagnosed cancers in men worldwide. Perineural invasion (PNI), the movement of cancer cells along nerves, is a commonly observed approach to tumor spread and is important in both research and clinical practice of prostate cancer. However, despite many studies reporting on molecules and pathways involved in PNI, understanding its clinical relevance remains insufficient. In this review, we aim to summarize the current knowledge of mechanisms and prognostic significance of PNI in prostate cancer, which may provide new perspectives for future studies and improved treatment.

Abstract

Perineural invasion (PNI) is a common indication of tumor metastasis that can be detected in multiple malignancies, including prostate cancer. In the development of PNI, tumor cells closely interact with the nerve components in the tumor microenvironment and create the perineural niche, which provides a supportive surrounding for their survival and invasion and benefits the nerve cells. Various transcription factors, cytokines, chemokines, and their related signaling pathways have been reported to be important in the progress of PNI. Nevertheless, the current understanding of the molecular mechanism of PNI is still very limited. Clinically, PNI is commonly associated with adverse clinicopathological parameters and poor outcomes for prostate cancer patients. However, whether PNI could act as an independent prognostic predictor remains controversial among studies due to inconsistent research aim and endpoint, sample type, statistical methods, and, most importantly, the definition and inclusion criteria. In this review, we provide a summary and comparison of the prognostic significance of PNI in prostate cancer based on existing literature and propose that a more standardized description of PNI would be helpful for a better understanding of its clinical relevance.

Preoperative Platelet Count Correlates With Postoperative Perineural Invasion on Specimen in Patients Treated With Radical Prostatectomy

Objective

It has been reported that perineural invasion (PNI) after radical prostatectomy (RP) is associated with unfavorable prostate cancer (PCa) prognosis. However, the clinicopathological factors especially hematological parameters that influenced PNI remain unknown. Our aim was to explore the relationship between clinicopathological parameters and PNI in patients who underwent RP.

Methods

A total of 348 patients with PCa who underwent RP at our center between 2018 and 2021 were consecutively collected. We divided them into non-PNI and PNI groups based on PNI status and compared clinicopathological characteristics including hematological parameters between non-PNI and PNI groups. The association of clinicopathological parameters including whole blood parameters, age, body mass index (BMI), hypertension, diabetes mellitus, prostate-specific antigen (PSA), ISUP (International Society of Urological Pathology) grade, pathological stage T (pT), and neoadjuvant hormonal therapy (NHT) with PNI was determined by univariate and multivariate logistic regression analyses.

Results

The pathological results of the RP specimen consisted of 254 (73.0%) patients with PNI and 94 (27.0%) cases without PNI. The level of PSA, percentages of advanced pT and grade, positive surgical margin rate, and vessel carcinoma embolus rate were significantly higher in the PNI group when compared with non-PNI counterpart (p = 0.007, p < 0.001, p < 0.001, p < 0.001, and p < 0.001, respectively). Among the whole blood parameters, only platelet count and plateletcrit were significantly different [216 (178.8–252.0) vs. 200.5 (173.5–236.5), p = 0.04; 0.0021 (0.0018–0.0025) vs. 0.0020 (0.0017–0.0023), p = 0.008, respectively]. Univariate logistic regression analysis demonstrated that platelet, ISUP, and pT were all positively correlated with the presence of PNI (T3 vs. T1, odds ratio (OR) = 2.029, p = 0.020; OR = 1.697, p < 0.001; OR = 3.836, p < 0.001). In the stepwise multivariate regression analysis, the association between platelet and PNI remained significant (T2 vs. T1, OR = 2.171, 95% CI: 1.082–4.354, p = 0.029; T3 vs. T1, OR = 2.595, 95% CI: 1.259–5.349, p = 0.010) after adjusting for confounding factors including age, BMI, hypertension, diabetes mellitus, PSA, ISUP, pT, and NHT.

Conclusions

The study first revealed that platelet count rather than other whole blood parameters was independently associated with the presence of PNI in patients with PCa, suggesting that platelets might play an essential role in PCa aggressiveness.

Detection of perineural invasion in prostate needle biopsies with deep neural networks

The presence of perineural invasion (PNI) by carcinoma in prostate biopsies has been shown to be associated with poor prognosis. The assessment and quantification of PNI are, however, labor intensive. To aid pathologists in this task, we developed an artificial intelligence (AI) algorithm based on deep neural networks. We collected, digitized, and pixel-wise annotated the PNI findings in each of the approximately 80,000 biopsy cores from the 7406 men who underwent biopsy in a screening trial between 2012 and 2014. In total, 485 biopsy cores showed PNI. We also digitized more than 10% (n = 8318) of the PNI negative biopsy cores. Digitized biopsies from a random selection of 80% of the men were used to build the AI algorithm, while 20% were used to evaluate its performance. For detecting PNI in prostate biopsy cores, the AI had an estimated area under the receiver operating characteristics curve of 0.98 (95% CI 0.97-0.99) based on 106 PNI positive cores and 1652 PNI negative cores in the independent test set. For a pre-specified operating point, this translates to sensitivity of 0.87 and specificity of 0.97. The corresponding positive and negative predictive values were 0.67 and 0.99, respectively. The concordance of the AI with pathologists, measured by mean pairwise Cohen's kappa (0.74), was comparable to inter-pathologist concordance (0.68 to 0.75). The proposed algorithm detects PNI in prostate biopsies with acceptable performance. This could aid pathologists by reducing the number of biopsies that need to be assessed for PNI and by highlighting regions of diagnostic interest.

Perineural invasion detected in prostate biopsy is a predictor of positive surgical margin of radical prostatectomy specimen: A meta-analysis

The role of perineural invasion detected by puncture biopsy of prostate cancer remains controversial. We performed a meta-analysis to assess the relationship between positive perineural invasion at prostate biopsy and positive surgical margins (PSM) after radical prostatectomy. We searched a number of relevant electronic databases including Web of Science, Medline, PubMed, Embase, and the Cochrane Library until 31 March 2021. STATA 15.1 software was used to analyse all data for this article. The quality of these studies was assessed by the Newcastle-Ottawa Scale (ranged from 0 to 9 stars). Finally, we selected 13 high-quality studies in our meta-analysis, which contain 8283 patients. Overall pooled analysis proposed that biopsy perineural invasion was related to a higher risk of the positive surgical margins after radical prostatectomy in prostate cancer (RR: 1.73; 95% CI: 1.56-1.92; z = 10.30, p = 0.000). Moreover, the outcomes of the publication bias checkout testified that without significant bias arose (Egger's test: 0.086 > 0.05; Begg's test: 0.59 > 0.05). The existing evidence indicates that higher incidence of positive surgical margins in patients who had perineural invasion was detected in prostate biopsy.

The Evolving Clinical Management of Genitourinary Cancers Amid the COVID-19 Pandemic

Coronavirus disease-2019 (COVID-19), a disease caused by Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) infection, has become an unprecedented global health emergency, with fatal outcomes among adults of all ages throughout the world. There is a high incidence of infection and mortality among cancer patients with evidence to support that patients diagnosed with cancer and SARS-CoV-2 have an increased likelihood of a poor outcome. Clinically relevant changes imposed as a result of the pandemic, are either primary, due to changes in timing or therapeutic modality; or secondary, due to altered cooperative effects on disease progression or therapeutic outcomes. However, studies on the clinical management of patients with genitourinary cancers during the COVID-19 pandemic are limited and do little to differentiate primary or secondary impacts of COVID-19. Here, we provide a review of the epidemiology and biological consequences of SARS-CoV-2 infection in GU cancer patients as well as the impact of COVID-19 on the diagnosis and management of these patients, and the use and development of novel and innovative diagnostic tests, therapies, and technology. This article also discusses the biomedical advances to control the virus and evolving challenges in the management of prostate, bladder, kidney, testicular, and penile cancers at all stages of the patient journey during the first year of the COVID-19 pandemic.

Sextant Biopsy-Based Criteria for Clinically Insignificant Prostate Cancer Are Also Valid for the 12-Core Prostate Biopsy Scheme: A Multicenter Study of Urooncology Association, Turkey

BACKGROUND

Epstein criteria based on sextant biopsy are assumed to be valid for 12-core biopsies. However, very scarce information is present in the current literature to support this view.

OBJECTIVES

To investigate the validity of Epstein criteria for clinically insignificant prostate cancer (PCa) in a cohort of the currently utilized 12-core prostate biopsy (TRUS-Bx) scheme in patients with low-risk and intermediate-risk PCa.

METHOD

Pathological findings were separately evaluated in the areas matching the sextant biopsy (6-core paramedian) scheme and in all 12-core schemes. Patients were divided into 2 groups according to the final pathology report of RP as true clinically significant PCa (sPCa) and insignificant PCa (insPCa) groups. Predictive factors (including Epstein criteria) and cutoff values for the presence of insPCa were separately evaluated for 6- and 12-core TRUS-Bx schemes. Then, different predictive models based on Epstein criteria with or without additional biopsy findings were created.

RESULTS

A total of 442 patients were evaluated. PSA density, biopsy GS, percentage of tumor and number of positive cores, PNI, and HG-PIN were independent predictive factors for insPCa in both TRUS-Bx schemes. For the 12-core scheme, the best cutoff values of tumor percentage and number of positive cores were found to be ≤50% (OR: 3.662) and 1.5 cores (OR: 2.194), respectively. The best predictive model was found to be that which added 3 additional factors (PNI and HG-PIN absence and number of positive cores) to Epstein criteria (OR: 6.041).

CONCLUSIONS

Using a cutoff value of "1" for the number of positive biopsy cores and absence of biopsy PNI and HG-PIN findings can be more useful for improving the prediction model of the Epstein criteria in the 12-core biopsy scheme.

Interobserver reproducibility of perineural invasion of prostatic adenocarcinoma in needle biopsies

Numerous studies have shown a correlation between perineural invasion (PNI) in prostate biopsies and outcome. The reporting of PNI varies widely in the literature. While the interobserver variability of prostate cancer grading has been studied extensively, less is known regarding the reproducibility of PNI. A total of 212 biopsy cores from a population-based screening trial were included in this study (106 with and 106 without PNI according to the original pathology reports). The glass slides were scanned and circulated among four pathologists with a special interest in urological pathology for assessment of PNI. Discordant cases were stained by immunohistochemistry for S-100 protein. PNI was diagnosed by all four observers in 34.0% of cases, while 41.5% were considered to be negative for PNI. In 24.5% of cases, there was a disagreement between the observers. The kappa for interobserver variability was 0.67–0.75 (mean 0.73). The observations from one participant were compared with data from the original reports, and a kappa for intraobserver variability of 0.87 was achieved. Based on immunohistochemical findings among discordant cases, 88.6% had PNI while 11.4% did not. The most common diagnostic pitfall was the presence of bundles of stroma or smooth muscle. It was noted in a few cases that collagenous micronodules could be mistaken for a nerve. The distance between cancer and nerve was another cause of disagreement. Although the results suggest that the reproducibility of PNI may be greater than that of prostate cancer grading, there is still a need for improvement and standardization.

MAOA promotes prostate cancer cell perineural invasion through SEMA3C/PlexinA2/NRP1-cMET signaling

Perineural invasion (PNI), a pathologic feature defined as cancer cell invasion in, around, and through nerves, is an indicator of poor prognosis and survival in prostate cancer (PC). Despite widespread recognition of the clinical significance of PNI, the molecular mechanisms are largely unknown. Here, we report that monoamine oxidase A (MAOA) is a clinically and functionally important mediator of PNI in PC. MAOA promotes PNI of PC cells in vitro and tumor innervation in an orthotopic xenograft model. Mechanistically, MAOA activates SEMA3C in a Twist1-dependent transcriptional manner, which in turn stimulates cMET to facilitate PNI via autocrine or paracrine interaction with coactivated PlexinA2 and NRP1. Furthermore, MAOA inhibitor treatment effectively reduces PNI of PC cells in vitro and tumor-infiltrating nerve fiber density along with suppressed xenograft tumor growth and progression in mice. Collectively, these findings characterize the contribution of MAOA to the pathogenesis of PNI and provide a rationale for using MAOA inhibitors as a targeted treatment for PNI in PC.

Extracapsular extension on multiparametric magnetic resonance imaging better predicts pT3 disease at radical prostatectomy compared to perineural invasion on biopsy

INTRODUCTION

Risk assessment for non-organ-confined prostate cancer (PCa) is important in the surgical planning for radical prostatectomy (RP). Perineural invasion (PNI) on prostate biopsy has been associated with adverse pathological outcomes at prostatectomy. Similarly, the identification of suspected extracapsular extension (ECE) on multiparametric magnetic resonance imaging (mpMRI) has been shown to predict non-organ-confined disease. However, no prior study has compared these factors in predicting adverse pathology at prostatectomy. We evaluated mpMRI ECE and prostate biopsy PNI on multivariable analysis to determine their ability to predict pathological stage at time of RP.

METHODS

We retrospectively investigated the prostatectomy database at our institution to identify men who underwent prostate biopsy with pre-biopsy mpMRI and subsequent RP from 2013-2017. Multivariable regression analysis was performed to compare the association of mpMRI ECE (mECE) and PNI on prostate biopsy on the likelihood of finding pT3 disease on pathology post-prostatectomy.

RESULTS

Of a total 454 RP between 2013 and 2017, 191 patients met our inclusion criteria. Stage pT2 and pT3+ were found in 120 (62.8%) and 71 (37.2%) patients, respectively. Patients with mECE had 4.84 cumulative odds of worse pathological stage on RP (p=0.045) compared to PNI on biopsy, which showed cumulative odds of 2.25 (p=0.048). When controlling only for those patients without PNI, mECE was still found to be a significant predictor of pT3 disease at RP (p=0.030); however, in patients without mECE, PNI was not significant (p=0.062).

CONCLUSIONS

While mECE and biopsy PNI were both associated with worse pathological stage on RP, mECE had significantly higher cumulative odds compared to PNI. The significant predictive ability of mECE adds further clinical value to the use of mpMRI in PCa management. While validation in a larger cohort is required, these factors have important clinical implications with regards to early diagnosis of advanced disease and surgical planning.

Perineural invasion on biopsy specimen as predictor of tumor progression in aging male treated with radical prostatectomy. Could we use it for pre-surgical screening?

We aimed to analyze the correlation of perineural invasion on transrectal ultrasound guided prostate biopsy with predictors of biochemical cancer recurrence, as well as its impact on clinical outcomes, for non-metastatic prostate cancer. For the study, patients with perineural invasion (N = 86) were recruited into group I and underwent open retropubic prostatectomy, regardless of clinical stage; cases with prostate cancer but without perineural invasion on biopsy, who received radical prostatectomy as the treatment modality, were placed into group II (n = 90). Perineural invasion was detected preoperatively in 43% of cases that revealed surgical margin positivity postoperatively, while 85% of the remaining cases (group II) had negative surgical margins. There was no correlation on prostate biopsy between perineural invasion and Gleason score or PSA, based on Sperman's rank-order correlation analysis. However, there was strong positive correlation of perineural invasion with clinical stage and patients age. Additionaly, we demonstrated that perineural invasion on biopsy is a non-independent risk factor for metastatic occurrence, although the correlation was significant in univariate analysis. Nevertheless, we found strong correlation between invasion on initial biopsy specimen with biochemical cancer recurrence, suggesting that perineural invasion on prostate biopsy is a significant predictor of worse prognostic outcome.

Perineural invasion by prostate adenocarcinoma in needle biopsies predicts bone metastasis: Ten year data from the TROG 03.04 RADAR Trial

AIMS

Perineural invasion (PNI) by prostatic adenocarcinoma is debated as a prognostic parameter. This study investigates the prognostic predictive value of PNI in a series of patients with locally advanced prostate cancer treated with radiotherapy and androgen deprivation using 10 years outcome data from the TROG 03.04 RADAR trial.

METHODS

Diagnostic prostate biopsies from 976 patients were reviewed and the presence of PNI noted. Patients were followed for 10 years according to the trial protocol or until death. The primary endpoint for the study was time to bone metastasis. Secondary endpoints included time to soft tissue metastasis, transition to castration resistance, prostate cancer-specific mortality and all-cause mortality.

RESULTS

PNI was detected in 449 cases (46%), with 234 cases (24%) having PNI in more than one core. The presence of PNI was significantly associated with higher ISUP grade, clinical T staging category, National Comprehensive Cancer Network risk group, and percent positive biopsy cores. The cumulative probability of bone metastases according to PNI status was significant over the 10 years follow-up interval of the study (log-rank test P < 0.0001). PNI was associated with all endpoints on univariable analysis. After adjusting for baseline clinicopathological and treatment factors, bone metastasis was the only endpoint in which PNI retained its prognostic significance (hazard ratio 1.42, 95% confidence interval 1.05-1.92, P = 0.021).

CONCLUSIONS

The association between PNI and the development of bone metastases supports the inclusion of this parameter as a component of the routine histology report. Further this association suggests that evaluation of PNI may assist in selecting those patients who should be monitored more closely during follow-up.

Prognostic value of perineural invasion in prostate needle biopsies: a population-based study of patients treated by radical prostatectomy

AIMS

Despite being one of the major pathways for the spread of malignant tumours, perineural invasion (PNI) has not conclusively been shown to have an independent prognostic value for prostate cancer. Prostatic biopsy constitutes the major pathology workload in prostate cancer and is the foundation for primary treatment decisions and for this reason we aimed to estimate the prognostic value of PNI in biopsies.

METHODS

We followed 918 men who underwent radical prostatectomy (RP) from the prospective and population based STHLM3 study until biochemical recurrence with a median follow-up of 4.1 years. To strengthen the evidence, we combined the estimates from the largest studies targeting the prognostic value of PNI in the biopsy. We also estimated the OR of advanced stage as radical prostatectomy for PNI positive and negative men.

RESULTS

The estimated prognostic value based on our data suggested an approximately 50% increased risk of biochemical recurrence if PNI was present in the biopsy (p=0.06). Even though not statistically significant on the 5% level, this estimate is consistent with similar studies, and by combining the estimates there is in fact strong evidence in support of an independent prognostic value of PNI in the biopsy (p<0.0001). There was also an independent increased risk of advanced stage at RP for positive men (OR 1.85, p=0.005).

CONCLUSIONS

The evidence supporting a clinically relevant and independent prognostic value of PNI is strong enough to be considered for pathology reporting guidelines.

Tumour innervation and neurosignalling in prostate cancer

Prostate cancer progression has been shown to be dependent on the development of autonomic nerves into the tumour microenvironment. Sympathetic nerves activate adrenergic neurosignalling that is necessary in early stages of tumour progression and for initiating an angiogenic switch, whereas parasympathetic nerves activate cholinergic neurosignalling resulting in tumour dissemination and metastasis. The innervation of prostate cancer seems to be initiated by neurotrophic growth factors, such as the precursor to nerve growth factor secreted by tumour cells, and the contribution of brain-derived neural progenitor cells has also been reported. Current experimental, epidemiological and clinical evidence shows the stimulatory effect of tumour innervation and neurosignalling in prostate cancer. Using nerves and neurosignalling could have value in the management of prostate cancer by predicting aggressive disease, treating localized disease through denervation and relieving cancer-associated pain in bone metastases.

Impact of biopsy perineural invasion on the outcomes of patients who underwent radical prostatectomy: a systematic review and meta-analysis

Objectives: To investigate the association between biopsy perineural invasion (PNI) and oncological outcomes of prostate cancer (PCa) after radical prostatectomy (RP).Materials and methods: A systematic literature search was performed using PubMed, EMBASE and Web of Science up to December 2018 to identify the eligible studies that included localized PCa patients who underwent biopsy and subsequently RP as well as follow-up information. Meta-analyses were conducted using available hazard ratios (HRs) of biopsy PNI from both univariate and multivariate analyses.Results: Eighteen studies including 14,855 patients with treatment follow-up information were included in the current systematic review. The rate of biopsy PNI varied between 7.0% and 33.0%. Seven out of the 18 studies that demonstrated biopsy PNI were associated with adverse pathologic features. Thirteen out of the 18 studies showed biopsy PNI correlated significantly with higher rates of biochemical recurrence (BCR)/cancer progression status or worse prognostic outcomes. With pooled data based on four studies with available univariate analysis results and four studies with multivariate analysis, statistically significant associations were found between biopsy PNI and BCR with univariate analysis (HR = 2.05; 95% CI = 1.57-2.68; p < 0.001) and with multivariate analysis (HR = 1.57; 95% CI = 1.28-1.93; p < 0.001).Conclusion: Evidence from the included observational studies indicated that biopsy PNI was not only correlated with adverse pathologic characteristics but also with worse BCR prognosis of local PCa after RP. The status of biopsy PNI could serve as a promising risk-stratification factor to help the decision-making process, considering active surveillance (AS) or further treatment for PCa patients.

Predictive factors for short-term biochemical recurrence-free survival after robot-assisted laparoscopic radical prostatectomy in high-risk prostate cancer patients

BACKGROUND

We aimed to assess the short-term oncological outcomes of robot-assisted laparoscopic radical prostatectomy to determine the predictive factors associated with biochemical recurrence in high-risk prostate cancer patients.

METHODS

A total of 331 patients with localized prostate cancer underwent robot-assisted laparoscopic radical prostatectomy. Of them, 113 patients were diagnosed with high-risk prostate cancer according to the D'Amico risk group classification. We evaluated the association between pre- or postoperative predictive factors and biochemical recurrence using Cox regression analysis.

RESULTS

The 2-year biochemical recurrence-free survival rate was 65.0% in the high-risk group. On univariate analyses, PSA level > 20 ng/mL, Gleason pattern 5 component on biopsy, pathological stage T3 or higher, perineural invasion, and positive surgical margin were predictive factors for biochemical recurrence. On multivariate analysis, PSA level > 20 ng/mL, Gleason pattern 5 component on biopsy, perineural invasion, and positive surgical margin were identified as independent predictive factors. The 2-year biochemical recurrence-free survival rate was 36.5% for patients with PSA level > 20 ng/mL and/or Gleason pattern 5 component on biopsy.

CONCLUSIONS

PSA level > 20 ng/mL and/or presence of the Gleason pattern 5 component on biopsy are predictive factors for early biochemical recurrence after robot-assisted laparoscopic radical prostatectomy in high-risk prostate cancer patients. We considered that these patients require a combined modality therapy to improve their prognosis.

The clinical significance of perineural invasion in patients with de novo metastatic prostate cancer

BACKGROUND

The clinical value of perineural invasion (PNI) in patients with localized prostate cancer (PCa) is widely explored. However, its role in metastatic PCa (mPCa) remains unknown.

OBJECTIVES

We aim to investigate the clinical significance of PNI in patients with mPCa.

MATERIALS AND METHODS

Data of 515 mPCa patients between 2012 and 2018 were retrospectively studied. PNI and its intensity were identified by prostate biopsy. The prognostic value of PNI was evaluated by Kaplan-Meier curves and Cox proportional-hazards model.

RESULTS

Perineural invasion was detected in 170/515 (33.0%) cases. Among them 73/170 (42.9%) and 97/170 (57.1%) harbored unifocal PNI (uni-PNI) and multifocal PNI (multi-PNI), respectively. Compared to patients without PNI, those with PNI had statistically shorter castration-resistant PCa-free survival (CFS) and numerically shorter overall survival (OS) (mCFS: 15.4- vs. 18.5-Mo, p = 0.015; mOS: 63.8- vs. 71.4-Mo, p = 0.108). Patients harboring multi-PNI were associated with poorer clinical outcomes than those with uni-PNI (mCFS: 12.4- vs. 18.0-Mo, p = 0.040; mOS: 39.7-Mo vs. NR, p = 0.018) or those without PNI (mCFS: 12.4- vs. 18.5-Mo, p = 0.002; mOS: 39.7- vs. 71.4-Mo, p = 0.002). Totally, neither uni-PNI nor multi-PNI was an independent risk factor impacting survival outcomes in multivariate analyses. While remarkably, for patients with favorable/intermediate-risk mPCa, multi-PNI was an independent adverse prognosticator for both CFS and OS (CFS: HR: 1.705, 95% CI: 1.029-2.825, p = 0.038; OS: HR: 3.294, 95% CI: 1.464-7.413, p = 0.004).

DISCUSSION AND CONCLUSION

This study filled the blank of the clinical significance of PNI in mPCa. We found that multi-PNI could distinguish men with relatively poor prognosis from patients initially regarded as with favorable survival outcomes by other prognosticators, and thus, avoid disease underestimation in this group of patients. Our finding would help physicians have a deeper understanding of the heterogeneity of mPCa and make better individualized therapeutic strategy.

The Perineural Invasion Paradox: Is Perineural Invasion an Independent Prognostic Indicator of Biochemical Recurrence Risk in Patients With pT2N0R0 Prostate Cancer? A Multi-Institutional Study

Purpose

Perineural invasion (PNI) is a histologic feature that is present in as many as 84% of patients with prostate cancer. The prognostic significance of PNI is controversial, with recent studies yielding contradictory results. This study aims to assess whether PNI, on the surgical pathology of patients with pT2N0M0 disease and with negative surgical margins, is an independent prognostic indicator of the risk of biochemical recurrence.

Methods and materials

We identified 1549 patients who received a diagnosis of margin-negative pT2N0M0 prostate cancer at 3 separate institutions between January 1, 2008 and December 31, 2014. We reviewed the electronic medical records of these patients and collected clinical and histologic data. A multivariable analysis was performed to assess the association between PNI and biochemical recurrence.

Results

Of the 1549 patients identified, 936 (60.4%) had PNI and 96 (6.2%) had biochemical recurrence. The median time until recurrence was 16 months. The median follow-up in patients without recurrence was 26.5 months. PNI was associated with pT2c disease. The proportion of patients with pT2c was 89% in patients with PNI compared with 79% in patients without PNI (P < .001). PNI was also associated with a higher surgical Gleason score (of those with vs without PNI, 21% vs 50% had Gleason score 3 + 3; 62% vs 41% had a Gleason score 3 + 4, 12% vs 5% had a Gleason score 4 + 3; and 5% vs 3% had a Gleason score 8-10; P < .001). On univariate analysis, patients with PNI appeared to be more likely to have disease recurrence (hazard ratio: 1.7; 95% confidence interval, 1.1-2.6; P = .015). However, after adjusting for other variables, there was not a significant association between PNI and recurrence (hazard ratio: 1.1; 95% confidence interval, 0.70-1.8: P = .65).

Conclusions

We found that PNI was not an independent indicator of the risk of biochemical recurrence. Instead, PNI may be an indicator of unfavorable histology such as a high Gleason score or diffuse disease within the prostate in pT2N0 patients.

Detection of extraprostatic disease and seminal vesicle invasion in patients undergoing magnetic resonance imaging-targeted prostate biopsies

Background

Finding incidental extraprostatic extension (EPE) or seminal vesicle invasion (SVI) by prostate cancer (PCa) is rare on standard prostate biopsy. We evaluated the clinical-pathologic features associated with EPE and SVI on multiparametric magnetic resonance imaging (MRI)/ultrasound (US) fusion-guided targeted biopsy (TB).

Methods

A retrospective review was performed from 2014-2017, selecting patients who had undergone TB. Clinical, pathologic, and radiologic features were evaluated.

Results

Five out of 333 (1.5%) patients who had PCa detected on TB had EPE and/or SVI. The average age and prostate-specific antigen (PSA) was 71 years and 17 ng/mL, respectively. The average number of cores taken on TB was 4.2. Two patients had a prior negative SB and two patients had a prior positive SB, one of which underwent radiation therapy. All patients had a PIRADSv2 suspicion score of 4 or 5. Four out of five (80%) patients underwent both SB and concurrent TB, of which 3/4 (75%) had EPE identified only on TB. One out of four (25%) patients also had both EPE and SVI, identified only on TB. One patient underwent only TB for MRI suspicion of SVI, which was pathologically confirmed on TB. On TB, one patient had Grade Group 3, two patients had Grade Group 4, and two patients had Grade Group 5 PCa. Perineural invasion (PNI) was present in 4/5 (80%) patients on TB.

Conclusions

Based on our small series, we hypothesize that MRI/US fusion TB outperforms SB in the identification of EPE and SVI. However, given the small sample size and the overall rarity of these pathologic findings on prostate biopsy, further validation is needed.

Both acute and chronic inflammation are associated with less perineural invasion in men with prostate cancer on repeat biopsy

OBJECTIVES

To evaluate the association between acute and chronic inflammation with the presence of perineural invasion (PNI) in prostate biopsies positive for prostate cancer (PCa).

MATERIAL AND METHODS

We conducted a retrospective analysis of 1 399 prostate biopsies positive for PCa in the Reduction by Dutasteride of PCa Events (REDUCE) study. PCa, acute and chronic prostate inflammation and PNI were assessed by central pathology review. The association between acute and chronic inflammation with PNI was evaluated using chi-squared and Kruskal-Wallis tests, and logistic regression adjusting for clinicopathological and biochemical variables.

RESULTS

The presence of PNI was identified in 133 biopsies (9.5%). In all, 267 biopsies (19.1%) had acute inflammation, 1 038 (74.2%) had chronic inflammation, and 255 (18.2%) had both. The presence of both acute and chronic inflammation had a mutual association (P < 0.001). Chronic inflammation was associated with a lower Gleason score (P = 0.009) and lower tumour volume (P < 0.001), while acute inflammation was associated with lower Gleason score (P = 0.04), lower tumour volume (P = 0.004) and higher prostate-specific antigen levels (P = 0.05). In both univariable and multivariable analyses, chronic prostate inflammation was significantly associated with less PNI (univariable odds ratio [OR] 0.54, 95% confidence interval [CI] 0.37-0.79, P = 0.001; multivariable OR 0.65, 95% CI 0.43-0.99, P = 0.045). Acute prostate inflammation was associated with less PNI only in univariable analysis (univariable OR 0.51, 95% CI 0.29-0.89, P = 0.018; multivariable OR 0.63, 95% CI 0.35-1.13, P = 0.12).

CONCLUSION

Acute and chronic prostate inflammation were both associated with a lower prevalence of PNI in prostate biopsies positive for PCa. If confirmed, this suggests that inflammation and immunomodulation can serve as areas of potential therapeutic design to mitigate PNI in patients with PCa.

Should reporting of peri-neural invasion and extra prostatic extension be mandatory in prostate cancer biopsies? correlation with outcome in biopsy cases treated conservatively

The identification of perineural invasion (PNI) and extraprostatic extension (ECE) in prostate cancer (PC) biopsies is time consuming and can be difficult. Although this is required information in many datasets, there is little evidence on their effect on outcome in patients treated conservatively. Cases of PC were identified from three cancer registries in the UK from men with clinically localized prostate cancer diagnosed by needle biopsy from 1990-2003. The endpoint was prostate cancer death (DOD). Patients treated radically within 6 months, those with objective evidence of metastases or who had prior hormone therapy were excluded. Follow-up was through cancer registries up until 2012. Deaths were divided into those from PC and those from other causes, according to WHO criteria. 988 biopsy cases (6522 biopsy cores) were centrally reviewed by three uropathologists and assigned a Gleason score and Grade Group (GG). The presence of both PNI and ECE was recorded. Of 988 patients, PNI was present in 288 (DOD = 75) and ECE in 23 (DOD = 5). On univariable analysis PNI was highly significantly associated with DOD (hazard ratio [HR] 2.28, 95% CI: 1.68, 3.1, log-rank test p-value = 4.8 × 10-8), but ECE was not (log-rank test p-value = 0.334). On multivariable analysis with GG, serum PSA (per 10%), clinical stage and extent of disease (per 10%), PNI lost significance (HR 1.16, 95% CI: 0.83, 1.63, likelihood ratio test p-value = 0.371). The utility of routinely examining prostate biopsies for ECE and PNI is doubtful as it is not independently associated with higher grade, stage or prognosis.

Effects of perineural invasion on biochemical recurrence and prostate cancer-specific survival in patients treated with definitive external beam radiotherapy

OBJECTIVES

Perineural invasion (PNI) has not yet gained universal acceptance as an independent predictor of adverse outcomes for prostate cancer treated with external beam radiotherapy (EBRT). We analyzed the prognostic influence of PNI for a large institutional cohort of prostate cancer patients who underwent EBRT with and without androgen deprivation therapy (ADT).

MATERIAL AND METHODS

We, retrospectively, reviewed prostate cancer patients treated with EBRT from 1993 to 2007 at our institution. The primary endpoint was biochemical failure-free survival (BFFS), with secondary endpoints of metastasis-free survival (MFS), prostate cancer-specific survival (PCSS), and overall survival (OS). Univariate and multivariable Cox proportional hazards models were constructed for all survival endpoints. Hazard ratios for PNI were analyzed for the entire cohort and for subsets defined by NCCN risk level. Additionally, Kaplan-Meier survival curves were generated for all survival endpoints after stratification by PNI status, with significant differences computed using the log-rank test.

RESULTS

Of 888 men included for analysis, PNI was present on biopsy specimens in 187 (21.1%). PNI was associated with clinical stage, pretreatment PSA level, biopsy Gleason score, and use of ADT (all P<0.01). Men with PNI experienced significantly inferior 10-year BFFS (40.0% vs. 57.8%, P = 0.002), 10-year MFS (79.7% vs. 89.0%, P = 0.001), and 10-year PCSS (90.9% vs. 95.9%, P = 0.009), but not 10-year OS (67.5% vs. 77.5%, P = 0.07). On multivariate analysis, PNI was independently associated with inferior BFFS (P<0.001), but not MFS, PCSS, or OS. In subset analysis, PNI was associated with inferior BFFS (P = 0.04) for high-risk patients and with both inferior BFFS (P = 0.01) and PCSS (P = 0.05) for low-risk patients. Biochemical failure occurred in 33% of low-risk men with PNI who did not receive ADT compared to 8% for low-risk men with PNI treated with ADT (P = 0.01).

CONCLUSION

PNI was an independently significant predictor of adverse survival outcomes in this large institutional cohort, particularly for patients with NCCN low-risk disease. PNI should be carefully considered along with other standard prognostic factors when treating these patients with EBRT. Supplementing EBRT with ADT may be beneficial for select low-risk patients with PNI though independent validation with prospective studies is recommended.

Perineural invasion as an independent predictor of biochemical recurrence in prostate cancer following radical prostatectomy or radiotherapy: a systematic review and meta-analysis

BACKGROUND

Although numerous studies have shown that perineural invasion (PNI) is linked to prostate cancer (PCa) risk, the results have been inconsistent. This study aimed to explore the association between PNI and biochemical recurrence (BCR) in patients with PCa following radical prostatectomy (RP) or radiotherapy (RT).

METHODS

According to the PRISMA statement, we searched the PubMed, EMBASE, Chinese National Knowledge Infrastructure (CNKI) and Wan Fang databases from inception to May 2017. Hazard ratios (HRs) and 95% confidence intervals (95% CIs) were extracted from eligible studies. Fixed or random effects model were used to calculate pooled HRs and 95% CIs according to heterogeneity. Publication bias was calculated by Begg's test.

RESULTS

Ultimately, 19 cohort studies that met the eligibility criteria and that involved 13,412 patients (82-2,316 per study) were included in this meta-analysis. The results showed that PNI was associated with higher BCR rates in patients with PCa after RP (HR=1.23, 95% CI: 1.11, 1.36, p<0.001) or RT (HR=1.22, 95% CI: 1.12, 1.34, p<0.001). No potential publication bias was found among the included studies in the RP group (p-Begg = 0.124) or the RT group (p-Begg = 0.081).

CONCLUSIONS

This study suggests that the presence of PNI by histopathology is associated with higher risk of BCR in PCa following RP or RT, and could serve as an independent prognostic factor in patients with PCa.

Effects of perineural invasion in prostate needle biopsy on tumor grade and biochemical recurrence rates after radical prostatectomy

To predict local invasive disease before retropubic radical prostatectomy (RRP), the correlation of perineural invasion (PNI) on prostate needle biopsy (PNB) and RRP pathology data and the effect of PNI on biochemical recurrence (BR) were researched. For patients with RRP performed between 2005 and 2014, predictive and pathologic prognostic factors were assessed. Initially all and D'Amico intermediate-risk group patients were comparatively assessed in terms of being T2 or T3 stage on RRP pathology, positive or negative for PNI presence on PNB and positive or negative BR situation. Additionally the effect of PNI presence on recurrence-free survival (RFS) rate was investigated. When all patients are investigated, multivariate analysis observed that in T3 patients PSA, PNB Gleason score (GS) and tumor percentage were significantly higher; in PNI positive patients PNB GS, core number and tumor percentage were significantly higher and in BR positive patients PNB PNI positivity and core number were significantly higher compared to T2, PNI negative and BR negative patients, separately (p < 0.05). When D'Amico intermediate-risk patients are evaluated, for T3 patients PSA and PNB tumor percentage; for PNI positive patients PNB core number and tumor percentage; and for BR positive patients PNB PNI positivity were significantly higher compared to T2, PNI negative and BR negative patients, separately (p < 0.05). Mean RFS in the whole patient group was 56.4 ± 4.2 months for PNI positive and 96.1 ± 5.7 months for negative groups. In the intermediate-risk group, mean RFS was 53.7 ± 5.1 months for PNI positive and 100.3 ± 7.7 months for negative groups (p < 0.001). PNI positivity on PNB was shown to be an important predictive factor for increased T3 disease and BR rates and reduced RFS.

Prostate cancer reporting and staging: needle biopsy and radical prostatectomy specimens

Prostatic adenocarcinoma remains the most common cancer affecting men. A substantial majority of patients have the diagnosis made on thin needle biopsies, most often in the absence of a palpable abnormality. Treatment choices ranging from surveillance to radical prostatectomy or radiation therapy are largely driven by the pathologic findings in the biopsy specimen. The first part of this review focuses on important morphologic parameters in needle biopsy specimens that are not covered in the accompanying articles. This includes tumor quantification as well as other parameters such a extraprostatic extension, seminal vesicle invasion, perineural invasion, and lymphovascular invasion. For those men who undergo radical prostatectomy, pathologic stage and other parameters are critical in prognostication and in determining the appropriateness of adjuvant therapy. Staging parameters, including extraprostatic extension, seminal vesicle invasion, and lymph node status are discussed here. Surgical margin status is also an important parameter and definitions and reporting of this feature are detailed. Throughout the article the current reporting guidelines published by the College of American Pathologists and the International Collaboration on Cancer Reporting are highlighted.

Perineural Invasion and Risk of Lethal Prostate Cancer

Background: Prostate cancer has a propensity to invade and grow along nerves, a phenomenon called perineural invasion (PNI). Recent studies suggest that the presence of PNI in prostate cancer has been associated with cancer aggressiveness.Methods: We investigated the association between PNI and lethal prostate cancer in untreated and treated prostate cancer cohorts: the Swedish Watchful Waiting Cohort of 615 men who underwent watchful waiting, and the U.S. Health Professionals Follow-Up Study of 849 men treated with radical prostatectomy. One pathologist performed a standardized histopathologic review assessing PNI and Gleason grade. Patients were followed from diagnosis until metastasis or death.Results: The prevalence of PNI was 7% and 44% in the untreated and treated cohorts, respectively. PNI was more common in high Gleason grade tumors in both cohorts. PNI was associated with enhanced tumor angiogenesis, but not tumor proliferation or apoptosis. In the Swedish study, PNI was associated with lethal prostate cancer [OR 7.4; 95% confidence interval (CI), 3.6-16.6; P < 0.001]. A positive, although not statistically significant, association persisted after adjustment for age, Gleason grade, and tumor volume (OR 1.9; 95% CI, 0.8-5.1; P = 0.17). In the U.S. study, PNI predicted lethal prostate cancer independent of clinical factors (HR 1.8; 95% CI, 1.0, 3.3; P =0.04).Conclusions: These data support the hypothesis that perineural invasion creates a microenvironment that promotes cancer aggressiveness.Impact: Our findings suggest that PNI should be a standardized component of histopathologic review, and highlights a mechanism underlying prostate cancer metastasis. Cancer Epidemiol Biomarkers Prev; 26(5); 719-26. ©2017 AACR.

Predictive factors associated with biochemical recurrence following radical prostatectomy for pathological T2 prostate cancer with negative surgical margins

OBJECTIVE

The aim of this study was to determine factors associated with the development of biochemical recurrence (BCR) following radical prostatectomy in patients with pathological T2 prostate cancer and negative surgical margins.

MATERIALS AND METHODS

This retrospective multicentre cohort study included 1252 consecutive patients with pT2 pN0/Nx and negative surgical margins on radical prostatectomy and without any adjuvant treatment, performed in three Belgian centres. BCR-free survival curves were estimated using the Kaplan-Meier method. Univariate and multivariate analyses using the Cox proportional hazards model were performed to determine clinical and pathological predictive factors of BCR in this group of patients.

RESULTS

In total, 910 patients were included. BCR occurred in 107 patients (11.8%) at a median follow-up of 108 months. Overall 5 and 10 year BCR-free survival rates were 90% and 87%, respectively. On the multivariate analyses, serum prostate-specific antigen (PSA) level (p = .001) and surgical Gleason score of 7 or above (p = .001) were significantly associated with BCR in men with pathological T2 prostate cancer with negative surgical margins. Perineural invasion and capsular infiltration were not risk factors for recurrence.

CONCLUSIONS

This study identified unfavourable risk factors in patients with pathological T2 and negative surgical margins following radical prostatectomy. The results suggest that patients with a surgical Gleason score of 7 or higher, unknown lymph-node status and high PSA values are at increased risk of recurrence.

Biopsy Perineural Invasion in Prostate Cancer Patients Who Are Candidates for Active Surveillance by Strict and Expanded Criteria

OBJECTIVE

To evaluate the association of biopsy perineural invasion (PNI) with adverse pathologic findings on radical prostatectomy in patients who would have been candidates for active surveillance (AS).

METHODS

Using a prospectively populated database of 3084 men who underwent open radical prostatectomy, candidates for AS by strict (Johns Hopkins) and expanded (University of Toronto) criteria were identified. The presence of adverse pathologic features at radical prostatectomy was compared between those men with and without biopsy PNI.

RESULTS

Of 596 men who met strict criteria for AS, 16 (3%) had biopsy PNI. In the strict AS cohort, there were no differences in adverse pathologic features at radical prostatectomy between those with and without PNI. Of 1197 men who were candidates for AS by expanded criteria, 102 (9%) had biopsy PNI. Men with biopsy PNI in the expanded AS cohort were more likely to have extraprostatic extension (P < .001) and pathologic upgrading (P = .01) at prostatectomy. In addition, those with PNI had larger dominant nodules (P < .001), and cancer comprised a greater percentage of their prostate glands (P < .001). There was no difference in the proportion with a positive margin between the 2 groups (P = .77).

CONCLUSION

Biopsy PNI was rare in patients who met strict criteria for AS. Among those men who met expanded criteria, PNI was associated with adverse pathologic findings upon prostatectomy. The presence of biopsy PNI may have a role in further risk stratifying patients who meet expanded criteria for AS.

Perineural invasion on biopsy is associated with upstaging at radical prostatectomy in Gleason score 3 + 4 = 7 prostate cancer

This study assesses if perineural invasion (PNI) detected on biopsy with Gleason score (GS) 3 + 4 = 7 prostate cancer (PCa) is associated with upstaging/upgrading of disease after radical prostatectomy (RP). 154 patients with GS 3 + 4 = 7 PCa diagnosed from biopsy who underwent RP were assessed for PNI. The percentage of biopsy sites with PNI (%PNI) was also calculated. Pattern 4 morphologies (ill-defined glands [IDG], fused, cribriform, and glomerulations) were also assessed. Clinical information, GS and stage after RP were retrieved from the medical records. 45 % (69/154) of patients were upstaged (≥pT3) and 29 % (44/154) were upgraded to GS >3 + 4 = 7 after RP. 37 % (57/154) of patients had PNI which was associated with upstaging (RR 1.4; P = 0.04) but not upgrading (RR 0.9; P = 0.7). There was higher %PNI in upstaged patients (12.1 % ± 1.8 vs. 7.1 % ± 1.5, P = 0.03) with a significant correlation between %PNI and ≥pT3 (r = 0.178, P = 0.027). After multivariate analysis, only cribriform formations were significantly associated with upstaging (P = 0.009). The presence of PNI in biopsies with GS 3 + 4 = 7 PCa is associated with upstaging at RP but is a weaker predictor of ≥pT3 disease than cribriform morphology.

The relationship between perineural invasion, tumor grade, reactive stroma and prostate cancer-specific mortality: A clinicopathologic study on a population-based cohort

BACKGROUND

In vitro and in vivo studies have shown that nerves, tumor epithelium, and stroma interact and promote prostate cancer (PC) progression. Perineural invasion (PNI) is established amidst these interactions and may therefore indicate an aggressive PC phenotype. The purpose of the present study was to determine the relationship between PNI, tumor grade, reactive stroma, and PC-specific mortality.

METHODS

A population-based study on 318 patients, encompassing all cases of PC diagnosed by needle biopsies and without evidence of systemic metastasis at the time of diagnosis in Aust-Agder County in the period of 1991-1999. Patients were identified by cross-referencing the Cancer Registry of Norway. Clinical data were obtained by review of medical charts. Diagnostic prostate needle biopsies were reviewed with respect to presence of PNI, percentage of biopsy cores with PNI, Gleason score (GS), and reactive stromal grade (RSG). The endpoint was PC-specific mortality.

RESULTS

The presence of PNI was significantly associated with high tumor grade and abundant reactive stroma. The 10-year PC-specific survival for patients with and without PNI was 72% and 91%, respectively (P = 0.001, log rank). PNI predicted PC-specific mortality independently of clinical factors, though the effect of PNI was attenuated when adjusting for GS and RSG. However, a percentage of biopsy cores with PNI >50% was found to predict PC-specific mortality independently of other clinicopathologic parameters.

CONCLUSIONS

The present population-based study shows that PNI on diagnostic prostate needle biopsy is associated with increased risk of PC-specific mortality. Our findings demonstrate that the prognostic effect of PNI is dependent on an association with high grade carcinoma and reactive stroma. However; the impact of PNI on clinical outcome becomes stronger and independent of other clinicopathologic factors upon increased percentage of PNI positive biopsy cores. Thus, our study highlights the importance of PNI and microenvironmental interactions for the long-term outcome of PC.

Perineural invasion in prostate biopsy specimens is associated with increased bone metastasis in prostate cancer

BACKGROUND

We aimed to evaluate the relationship between perineural invasion (PNI) and bone metastasis in prostate cancer (PCa).

METHODS

We retrospectively reviewed the data of 633 PCas who had whole-body bone scan (WBBS) between 2008 and 2014. We recorded the age, clinical T-stage, total PSA (tPSA) prior to biopsy, Gleason sum (GS), and PNI in transrectal ultrasound guided biopsy (TRUS-Bx) and digital rectal examination findings. Bone metastases were assessed with WBBS and magnetic resonance image if WBBS was suspicious. We divided the patients into two groups according to NCCN criteria: (Group 1) bone scan not indicated, (Group 2) bone scan indicated.

RESULTS

There were 262 patients in Group 1 and 371 in 2. There is not significant relationship between PNI and bone metastasis in Group 1. However, there is very limited number of metastatic patients (n = 12) in this group. There is a strong relationship between PNI and bone metastasis in Group 2 (P = 0.001). Sensitivity, specificity and positive predictive value of PNI for bone metastasis were 72.4%, 81.7%, and 77.7%, respectively. In this group, tPSA, GS, positive DRE, and PNI were significant covariates for prediction of bone metastasis in univariate and multivariate analysis (except age). The most powerful predictor was PNI, and it increased the risk of bone metastasis 11-fold.

CONCLUSIONS

PNI in the TRUS-Bx specimens is the most powerful predictive histopathological feature for bone metastasis, by increasing the risk of bone metastasis 11-fold in NCCN bone scan indicated patients (Group 2).

Baseline Perineural Invasion is Associated with Shorter Time to Progression in Men with Prostate Cancer Undergoing Active Surveillance: Results from the REDEEM Study

PURPOSE

We evaluated the association of perineural invasion with disease progression in men with prostate cancer on active surveillance.

MATERIALS AND METHODS

We retrospectively analyzed the records of 302 men on active surveillance for low risk prostate cancer (T1c-T2a), Gleason 6 or less, 3 or fewer positive cores, 50% or less of any core involved and prostate specific antigen 11 ng/ml or less in the REduction by Dutasteride of clinical progression Events in Expectant Management (REDEEM) study. Patients underwent study mandated biopsies 18 and 36 months after enrollment. Disease progression was divided into pathological (4 or greater positive cores, 50% or greater core involvement, or Gleason greater than 6 on followup biopsy), therapeutic (any therapeutic prostate cancer intervention) or clinical (pathological or therapeutic progression). Time to disease progression was analyzed with Cox models adjusting for patient age, race, baseline prostate specific antigen, number of sampled and involved cores, tumor length and treatment.

RESULTS

A total of 11 patients (4%) had perineural invasion on baseline biopsy. Perineural invasion was not associated with any baseline features (each p >0.05). During the study clinical progression developed in 125 patients (41%), including pathological progression in 95. One, 2 and 3-year clinical progression-free survival for men with vs without perineural invasion was 82%, 27% and 27% vs 93%, 67% and 58%, respectively (p <0.05). On multivariable analyses perineural invasion was associated with clinical (HR 2.39, 95% CI 1.16-4.94, p = 0.019) and pathological progression (HR 2.21, 95% CI 0.92-5.33, p = 0.076).

CONCLUSIONS

Among patients with prostate cancer on active surveillance perineural invasion was associated with an increased risk of clinical progression. The 2-year risk of clinical progression with perineural invasion was 73%. If these results are confirmed, patients with perineural invasion may not be good active surveillance candidates.

Prostate cancer with perineural spread and dural extension causing bilateral lumbosacral plexopathy: case report

Perineural tumor spread in prostate cancer is emerging as a mechanism to explain select cases of neurological dysfunction and as a cause of morbidity and tumor recurrence. Perineural spread has been shown to extend from the prostate bed to the lumbosacral plexus and then distally to the sciatic nerve or proximally to the sacral and lumbar nerves and even intradurally. The authors present a case of a bilateral neoplastic lumbosacral plexopathy that can be explained anatomically as an extension of the same process: from one lumbosacral plexus to the contralateral one utilizing the dural sac as a bridge between the opposite sacral nerve roots. Their theory is supported by sequential progression of symptoms and findings on clinical examinations as well as high-resolution imaging (MRI and PET/CT scans). The neoplastic nature of the process was confirmed by a sciatic nerve fascicular biopsy. The authors believe that transmedian dural spread allows continuity of a neoplastic process from one side of the body to the other.

The chemokine (CCL2-CCR2) signaling axis mediates perineural invasion

Perineural invasion is a form of cancer progression where cancer cells invade along nerves. This behavior is associated with poor clinical outcomes; therefore, it is critical to identify novel ligand-receptor interactions between nerves and cancer cells that support the process of perineural invasion. A proteomic profiler chemokine array was used to screen for nerve-derived factors secreted from tissue explants of dorsal root ganglion (DRG), and CCL2 was identified as a lead candidate. Prostate cancer cell line expression of CCR2, the receptor to CCL2, correlated closely with MAPK and Akt pathway activity and cell migration towards CCL2 and DRG. In vitro nerve and cancer coculture invasion assays of perineural invasion demonstrated that cancer cell CCR2 expression facilitates perineural invasion. Perineural invasion is significantly diminished in coculture assays when using DRG harvested from CCL2(-/-) knockout mice as compared with control CCL2(+/+) mice, indicating that CCR2 is required for perineural invasion in this murine model of perineural invasion. Furthermore, 20 of 21 (95%) patient specimens of prostate adenocarcinoma with perineural invasion exhibited CCR2 expression by immunohistochemistry, while just 3 of 13 (23%) lacking perineural invasion expressed CCR2. In summary, nerve-released CCL2 supports prostate cancer migration and perineural invasion though CCR2-mediated signaling.

IMPLICATIONS

These results reveal CCL2-CCR2 signaling as a key ligand-receptor mechanism that mediates cancer cell communication with nerves during perineural invasion and highlight a potential future therapeutic target.

[Documentation quality of histopathology reports of prostate needle biopsies: a snapshot]

BACKGROUND

A standardized assessment of findings from prostate needle biopsies in pathology is of great importance for the individual recommendations for therapy of patients with prostate cancer. To this end criteria were developed which are formulated as recommendations in the S3 guidelines for prostate cancer and in joint instructions of the Bundesverband Deutscher Pathologen (BDP, "National Association of German Pathologists") and the Deutsche Gesellschaft für Pathologie (DGP, "German Society of Pathology"). In this article the findings from tumor positive prostate needle biopsies taken from various institutes in Germany, were investigated exclusively to determine to what extent the recommended parameters were followed.

MATERIAL AND METHODS

The study encompassed the findings from 91 patients with a mean age of 65.3 years from whom an average of 9.3 biopsy samples from different regions of the prostate were submitted. All diagnosed tumors corresponded to a standard type adenocarcinoma according to the classification of the World Health Organization (WHO) which was detected in an average of 2.5 biopsy regions per patient. The assessment was made from H & E stained serial sections which was supplemented in 11 (12.1%) cases by special staining methods and in 40 (44%) cases by immunohistochemical staining techniques. The length of the needle biopsy was documented in 88 (96.7%) cases and the tumor spread also in 88 cases. The tumor stage was reported in 16 cases (17.6%).

RESULTS

The Gleason grading score (GS) was reported in all 91 cases whereby the old GS was explicitly used in 1 case and the modified GS in all other cases. The allocated GS ranged from 4 to 10 whereby 8 cases were graded as ≤5, 46 as GS grade 6, 27 as GS grade 7 and 10 as GS >7. Out of 45 cases with several positive biopsy samples, 38 were uniformly graded (84.4%), 6 out of the 7 samples which were not uniformly graded were allocated a GS of 6 or 7 and 1 sample was graded as GS 6-9. In 64 cases (70.3%) the conventional 3-stage WHO grading (n=42) and the Helpap grading (n=22) were additionally used. The WHO and Helpap grading scores were found to be highly correlated with the GS grading scores and the Union for International Cancer Control (UICC) grading scores derived from it (χ²-test, p<0.001), although surprising allocations were selected in isolated cases.

CONCLUSION

In total, the only serious deficits were that in three cases (3.3%) no information was supplied on the estimated spread of the tumor in the tumor positive biopsies because this information can be decisive for therapy decisions, particularly for the selection of an active surveillance strategy. Also a relatively large number of cases were assigned a GS score ≤ 5 which is not recommended in the modified Gleason grading. Furthermore, translation of the GS into the other grading forms used revealed that the biological assessment of the GS showed clear differences between the various participating institutes. In conclusion, the findings of the pathologists as a rule incorporated all the parameters necessary for a therapy decision in accordance with the guidelines so that they can be considered comprehensive and completely valid apart from a few exceptions.

Prognostic histopathological and molecular markers on prostate cancer needle-biopsies: a review

Prostate cancer is diverse in clinical presentation, histopathological tumor growth patterns, and survival. Therefore, individual assessment of a tumor's aggressive potential is crucial for clinical decision-making in men with prostate cancer. To date a large number of prognostic markers for prostate cancer have been described, most of them based on radical prostatectomy specimens. However, in order to affect clinical decision-making, validation of respective markers in pretreatment diagnostic needle-biopsies is essential. Here, we discuss established and promising histopathological and molecular parameters in diagnostic needle-biopsies.

Aberrant methylation of PCDH10 predicts worse biochemical recurrence-free survival in patients with prostate cancer after radical prostatectomy

Background

Prostate cancer is a common malignancy in men, and inevitably some patients experience biochemical recurrence after radical prostatectomy. To date, there are no reliable predictors for prostate cancer recurrence, and novel predictors are urgently needed. PCDH10 (protocadherin-10) is a novel tumor suppressor gene, which is down-regulated by promoter methylation in prostate cancer. The aim of this study was to evaluate the feasibility of using PCDH10 methylation to predict the biochemical recurrence (BCR) of prostate cancer after radical prostatectomy.

Material/Methods

Fresh tissue samples were obtained from 151 patients with primary prostate cancer, and from 34 patients with benign prostatic hyperplasia (BPH) as control. The methylation status of PCDH10 in prostate cancer tissues and controls were examined using methylation-specific PCR (MSP), and then associated with clinicopathological features and BCR-free survival of patients with prostate cancer.

Results

We found that PCDH10 methylation was detected in 79 (52.3%) patients with prostate cancer, but no methylation was found in controls (P<0.0001). Moreover, PCDH10 methylation was significantly associated with higher preoperative prostate-specific antigen (PSA) level (P <0.0001), higher Gleason Score (P<0.0001), advanced clinical stage (P=0.0002), lymph node metastasis (P=0.0389), angiolymphatic invasion (P=0.0303), and biochemical recurrence (P=0.0068). Moreover, PCDH10 methylation was associated with poor BCR-free survival (P<0.0001), and may be used as an independent predictor of BCR-free survival (P=0.0046).

Conclusions

Our results indicate that PCDH10 methylation in prostate cancer tissue is an independent prognostic biomarker of worse BCR-free survival of patients with prostate cancer after radical prostatectomy.

The prognostic significance of perineural invasion and race in men considering active surveillance

OBJECTIVE

To determine the importance of perineural invasion (PNI) on diagnostic biopsy in men enrolled in active surveillance (AS).

PATIENTS AND METHODS

Eligibility criteria for AS included clinical stage ≤ T2a and Gleason score ≤6, ≤3 cores positive, maximum single core involvement <50%, and total tumour volume ≤5% on diagnostic biopsy. All men received 12-core confirmation biopsy at ≤6 months. AS 'failure' on confirmatory biopsy was defined as failure to meet one or more eligibility criteria. Risk of AS failure was compared in men with and without PNI.

RESULTS

For the 165 men comprising the study population, the mean (sd) age was 66.9 (6.5) years and the median (interquartile, IQR) PSA level of men at study entry was 4.4 (3.2-6.0) ng/mL. The median (IQR) follow-up was 5.5 (1.1-9.9) months. In all, 8.5% (14/165 men) had PNI on diagnostic biopsy. Compared with those without PNI, men with PNI tended to have more cores involved with cancer, at a mean (sd) of 2.0 (0.7) vs 1.6 (0.8) cores (P = 0.08) but did not have significantly a greater mean (sd) total tumour length on diagnostic biopsy, at 3.0 (2.1) vs 2.3 (3.6) mm (P = 0.27). Men with PNI on diagnostic biopsy were significantly more likely to meet criteria for disease progression on confirmatory biopsy (57% [8/14] vs 21% [32/151]; P = 0.006). PNI remained a significant predictor for AS failure after adjustment for number of positive cores, maximum percentage core involvement, and total tumour length (odds ratio 4.4, 95% confidence interval 1.4-14.2).

CONCLUSIONS

PNI on diagnostic biopsy is associated with disease progression on confirmatory biopsy. The presence of PNI should factor into appropriate patient selection and counselling in AS.