Significance of Prostate Adenocarcinoma Perineural Invasion on Biopsy in Patients Who are Otherwise Candidates for Active Surveillance

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.

Overcoming Drug Resistance in Advanced Prostate Cancer by Drug Repurposing

Prostate cancer (PCa) is the second most common cancer in men. Common treatments include active surveillance, surgery, or radiation. Androgen deprivation therapy and chemotherapy are usually reserved for advanced disease or biochemical recurrence, such as castration-resistant prostate cancer (CRPC), but they are not considered curative because PCa cells eventually develop drug resistance. The latter is achieved through various cellular mechanisms that ultimately circumvent the pharmaceutical’s mode of action. The need for novel therapeutic approaches is necessary under these circumstances. An alternative way to treat PCa is by repurposing of existing drugs that were initially intended for other conditions. By extrapolating the effects of previously approved drugs to the intracellular processes of PCa, treatment options will expand. In addition, drug repurposing is cost-effective and efficient because it utilizes drugs that have already demonstrated safety and efficacy. This review catalogues the drugs that can be repurposed for PCa in preclinical studies as well as clinical trials.

Transperineal multiparametric magnetic resonance imaging-ultrasound fusion-targeted prostate biopsy combined with standard template improves perineural invasion detection

Perineural invasion (PNI) on biopsy is associated with adverse features in prostate cancer (PCa). Transrectal multiparametric magnetic resonance imaging (MRI)-targeted biopsy (TBx) has shown to detect higher presence of PNI than standard template biopsy (SBx). Transperineal biopsy provides effective cancer detection with lower complications than the transrectal approach. We compared PNI detection efficiency between SBx and TBx through transperineal approach. We identified patients with PCa who underwent transperineal TBx and concomitant standard 20-core template SBx from September 2019 to February 2021. Clinical, MRI imaging and biopsy characteristics were evaluated and compared between TBx and SBx. Two hundred thirty-eight patients with PCa underwent concomitant transperineal SBx and TBx procedures. Combined PNI+ (SBxPNI+ and/or TBxPNI+) was identified in 77 of 238 (32.4%) patients. SBx detected 23.9% PNI-positive patients and TBx detected 19.3% PNI-positive patients of all patients with PCa. Patients with PNI were with significantly different clinicopathological characteristics than patients without PNI. Although significantly more positive PCa cores and higher positive PCa core rate were found in the SBx method, patients with SBxPNI+ only shared similar features as TBxPNI+only patients. Of 176 cases with both SBxPCa and TBxPCa, TBx could detect 19 (15.1%) more PNI cases than SBx while SBx could detect 24 (18.3%) more PNI cases than TBx. Multiparametric MRI fusion-targeted biopsy in combination with template biopsy through transperineal approach achieved PNI detection rate over 30% of PCa cases. The increased PNI detection may improve the model to select active surveillance candidates in clinical practice.

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.

Investigating association of perineural invasion on prostate biopsy with Gleason score upgrading at prostatectomy: A multi-institutional analysis

Background

The significance of perineural invasion (PNI) in prostate cancer (PC) is unclear. A recent report of patients with pT2N0R0 PC found that PNI at prostatectomy was independently associated with higher Gleason score and more diffuse prostatic disease. We aimed to test our hypothesis that PNI on prostate biopsy in pT2N0R0 patients is associated with increased Gleason score upgrading at prostatectomy.

Methods

We identified 2892 patients status post prostatectomy with pT2N0R0 PC from three institutions, diagnosed between 1 January 2008 and 31 December 2014. Multivariable logistic regression (MVA) was used to evaluate the association between prostate biopsy PNI status and surgical Gleason upgrading, while controlling for potential confounders.

Results

Of the 2892 patients identified, 14% had PNI on biopsy, of whom 21% had surgical Gleason upgrading, while 28% without PNI on biopsy had such upgrading (P < .01). On MVA, the odds ratio (OR) of surgical Gleason upgrading for patients with biopsy PNI relative to patients without biopsy PNI was 0.69 (P < .01). The variables associated with surgical Gleason upgrading were age ≤60 years (OR 1.22, P = .02) and preoperative PSA >4 ng/mL (OR 1.26, P = .02).

Conclusions

In post‐prostatectomy patients with favorable‐risk PC, PNI on prostate biopsy was not associated with surgical Gleason score upgrading. This may be due to the association of PNI with more diffuse disease, leading to increased biopsy tumor yield and grading accuracy. These findings suggest that in this setting, biopsy PNI alone should not be a concern for more aggressive disease requiring pathologic confirmation or intervention. This may help guide treatment decision‐making for men debating active surveillance, radiation, and surgery.

Nerves in cancer

The contribution of nerves to the pathogenesis of malignancies has emerged as an important component of the tumour microenvironment. Recent studies have shown that peripheral nerves (sympathetic, parasympathetic and sensory) interact with tumour and stromal cells to promote the initiation and progression of a variety of solid and haematological malignancies. Furthermore, new evidence suggests that cancers may reactivate nerve-dependent developmental and regenerative processes to promote their growth and survival. Here we review emerging concepts and discuss the therapeutic implications of manipulating nerves and neural signalling for the prevention and treatment of cancer.

Defining clinically significant prostate cancer on the basis of pathological findings

The definition of clinically significant prostate cancer is a dynamic process that was initiated many decades ago, when there was already evidence that a great proportion of patients with prostate cancer diagnosed at autopsy never had any clinical symptoms. Autopsy studies led to examinations of radical prostatectomy (RP) specimens and the establishment of the definition of significant cancer at RP: tumour volume of 0.5 cm³ , Gleason grade 6 [Grade Group (GrG) 1], and organ-confined disease. RP studies were then used to develop prediction models for significant cancer by the use of needle biopsies. The first such model was used to delineate the first active surveillance (AS) criteria, known as the 'Epstein' criteria, in which patients with a cancer Gleason score of 3 + 3 = 6 (GrG1) involving fewer than two cores, and <50% of any given core, and a prostate-specific antigen density of <0.15 ng/ml per cm³ had a minimal risk of significant cancer at RP. These were adopted as components of the 'very-low-risk category' of the National Comprehensive Cancer Network guidelines, in which AS is supported as a management option. With the increase in the popularity of AS, much research has been carried out to better define significant/insignificant cancer, in order to be able to safely offer AS to a larger proportion of patients without the risk of undertreatment. Research has focused on allowing higher volume tumours, focal extraprostatic extension, and a limited amount of Gleason pattern 4, and the significance of different morphological patterns of Gleason 4. Other areas of research that will probably impact on the field but that are not covered in this review include the molecular classification of tumours and imaging techniques.

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.

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.

The critical role of the pathologist in determining eligibility for active surveillance as a management option in patients with prostate cancer: consensus statement with recommendations supported by the College of American Pathologists, International Society of Urological Pathology, Association of Directors of Anatomic and Surgical Pathology, the New Zealand Society of Pathologists, and the Prostate Cancer Foundation

CONTEXT

Prostate cancer remains a significant public health problem. Recent publications of randomized trials and the US Preventive Services Task Force recommendations have drawn attention to overtreatment of localized, low-risk prostate cancer. Active surveillance, in which patients undergo regular visits with serum prostate-specific antigen tests and repeat prostate biopsies, rather than aggressive treatment with curative intent, may address overtreatment of low-risk prostate cancer. It is apparent that a greater awareness of the critical role of pathologists in determining eligibility for active surveillance is needed.

OBJECTIVES

To review the state of current knowledge about the role of active surveillance in the management of prostate cancer and to provide a multidisciplinary report focusing on pathologic parameters important to the successful identification of patients likely to succeed with active surveillance, to determine the role of molecular tests in increasing the safety of active surveillance, and to provide future directions.

DESIGN

Systematic review of literature on active surveillance for low-risk prostate cancer, pathologic parameters important for appropriate stratification, and issues regarding interobserver reproducibility. Expert panels were created to delineate the fundamental questions confronting the clinical and pathologic aspects of management of men on active surveillance.

RESULTS

Expert panelists identified pathologic parameters important for management and the related diagnostic and reporting issues. Consensus recommendations were generated where appropriate.

CONCLUSIONS

Active surveillance is an important management option for men with low-risk prostate cancer. Vital to this process is the critical role pathologic parameters have in identifying appropriate candidates for active surveillance. These findings need to be reproducible and consistently reported by surgical pathologists with accurate pathology reporting.

Pathological Correlation between Number of Biopsies and Radical Surgery: Does It Make a Difference to Final Pathology?

AIMS

To evaluate whether the number of biopsies performed via transrectal ultrasound (TRUS) accurately predicts pathological parameters such as Gleason sum, prostatic intraepithelial neoplasia and perineural invasion of the final prostatectomy specimen.

MATERIALS AND METHODS

The cohort consisted of 99 patients whom had undergone radical prostatectomy. Comparisons were made between the number of biopsies utilised and the presence of the pathological parameters from tissue at time of diagnosis and tissue from the final prostatectomy.

RESULTS

A significant difference was noted between Gleason sum, prostatic intraepithelial neoplasia and perineural invasion from tissue at time of diagnosis irrespective of the number of biopsies utilised and tissue from the radical specimen (p < 0.001, p < 0.001, p < 0.001 respectively). No difference was noted in the mean Gleason sum when 11-14 biopsies were utilised at TRUS and the Gleason sum from the radical specimen.

CONCLUSION

We have demonstrated that the number of biopsies utilised at time of TRUS for diagnosis predicts the accuracy of pathological parameters in the final radical prostatectomy specimen. We believe that 11-14 biopsies should be utilised at time of TRUS as this allows a higher accuracy in the Gleason sum and therefore allows optimum treatment plans to be devised.

Predicting the risk of non-organ-confined prostate cancer when perineural invasion is found on biopsy

OBJECTIVE

To more precisely define the risk of non-organ-confined (non-OC) prostate cancer among men with perineural invasion (PNI) identified on prostate biopsy.

MATERIALS AND METHODS

The Johns Hopkins radical prostatectomy database was queried for men with PNI reported on prostate biopsy. Patients with and without non-OC disease were compared for differences in preoperative clinical and pathologic characteristics, including three biopsy-based measures of tumor volume (number of cores with cancer, percentage of cores with cancer, and maximum percent core involvement with cancer). After evaluating the different preoperative variables in univariate analyses, a multivariable logistic regression model was generated, and bootstrap estimates of the risk of non-OC disease were calculated.

RESULTS

In total, 556 patients with PNI were analyzed, 279 (50.2%) of whom were found to have non-OC prostate cancer. In univariate analyses, preoperative prostate-specific antigen, clinical T stage, biopsy Gleason sum, and the three biopsy-based measures of tumor volume were significantly associated with non-OC disease. Of the three measures of tumor volume, the best fit to the data and highest degree of model discrimination were obtained using maximum percent core involvement with cancer. Incorporating this variable, preoperative prostate-specific antigen, clinical T stage, and biopsy Gleason sum into a multivariable model, the estimated risk of non-OC disease was found to range from 13.8% to 94.4% (bootstrap corrected c-index = 0.735).

CONCLUSION

Men with PNI on prostate biopsy are at a wide range of risk for non-OC disease. Preoperative estimation of this risk is improved by considering readily available biopsy estimates of tumor volume.

Variation in reporting of cancer extent and benign histology in prostate biopsies among European pathologists

It is not known how uropathologists currently report histopathological features of prostate biopsies such as core length, tumor extent, perineural invasion, and non-tumor-associated features such as inflammation and hyperplasia in needle biopsies. A web-based survey was distributed among 661 members of the European Network of Uropathology. Complete replies were received from 266 pathologists in 22 European countries. Total core lengths were reported by 64 %. The numbers of cores positive for cancer was given by 79 %. Linear cancer extent was reported by 81 %, most often given in millimeters for each core (53 %) followed by the estimation of percentage of cancer in each core (40 %). A gap of benign tissue between separate cancer foci in a single core would always be subtracted by 48 % and by 63 % if cancer foci were minute and widely separated. Perineural invasion was reported by 97 %. Fat invasion by tumor was interpreted as extraprostatic extension by 81 %. Chronic and active/acute inflammation was always reported by 32 and 56 % but only if pronounced by 54 and 39 %, respectively. While most (79 %) would never diagnose benign prostatic hyperplasia on needle biopsy, 21 % would attempt to make this diagnosis. Reporting practices for prostate biopsies are variable among European pathologists. The great variation in some methodologies used suggests a need for further international consensus, in order for retrospective data to be comparable between different institutions.