Clinical Findings and Treatment Outcomes in Patients with Extraprostatic Extension Identified on Prostate Biopsy

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.

Pathological Assessment of Men with Grade Group 2 Prostate Cancer

PURPOSE

A variety of treatment options are now available for men with localized prostate cancer (PC); however, there is still debate in determining how and when to intervene for Grade Group (GG) 2 disease. Our study aims to formulate strategies to identify men at risk of upgrading and having adverse pathological outcomes.

MATERIALS AND METHODS

This retrospective study includes 243 patients with GG2 PC that were treated with radical prostatectomy between 2015 and 2021. Patients on active surveillance, previous history of prostate biopsy, hormonal and/or radiation therapy prior to surgery were excluded from this study. A retrospective analysis was conducted using clinicopathological data obtained from medical records.

RESULTS

Prostate-specific antigen (PSA) and Prostate Imaging Reporting and Data System (PI-RADS) score were statistically significant variables for risk of upgrading. In men who had presence of composite poor outcomes, PSA, PI-RADS score, presence of extraprostatic extension and seminal vesical invasion on MRI, number of positive cores, percentage of high grade (pattern 4/5) on prostate biopsy and Gleason pattern 4 volume on biopsy were all statistically significant variables. Strategy 8 (PI-RADS 5 lesion or percentage high grade [Gleason pattern 4] on prostate biopsy grade >10% or >3 cores positive on prostate biopsy) had significant association to identifying the highest number of men with upgrading and composite poor outcomes.

CONCLUSIONS

Our study supports the use of strategy 8 in treatment decision making of men with GG2 PC. Further validation of the use of this strategy is warranted.

Incidence and Pitfalls of Adipose Tissue Encountered in Prostatic Transurethral Resections and Related Specimens

While the presence of adipose tissue and its involvement by prostatic cancer (extraprostatic extension) is well-recognized in prostate biopsies, adipose tissue in transurethral resections of the prostate (TURP) is largely unexplored. Herein, 200 consecutive TURPs and related specimens were reviewed, including a separate 3-year analysis of specimens containing prostatic cancer, with the following data collected: presence of fat, presence of cancer within fat, and quantity of fat. For specimens with both fat and prostatic cancer, specimen weight and tumor volume were recorded. Within the 200 consecutive TURPs and related specimens, adipose tissue was identified in 20%; 55% had 2.5 mm of adipose tissue; the number of fragments with adipose tissue ranged from 1 to 14. No correlation between specimen weight and measured extent of adipose tissue or number of fragments with adipose tissue was identified. Of all the specimens with prostatic cancer, 15/56 (27%) involved adipose tissue, with two specimens with large cancer volume (>90%) demonstrating extensive involvement of adipose tissue. Adipose tissue is frequently present within TURP and related specimens with variability in extent. The etiology behind encountering adipose tissue is uncertain, and it could represent resection into peri-prostatic fat, intraprostatic fat, or bladder neck fat sampling. Although encountering adipose tissue involved by cancer in TURP and related specimens may imply extraprostatic extension (pT3a), further studies are needed to corroborate these findings as well as to determine if these should be included in reported synoptics.

Multinational, Multicenter Evaluation of Prostate Cancer Tissue in Sub-Saharan Africa: Challenges and Opportunities

PURPOSE

Prostate cancer disproportionately affects men of African descent, yet their representation in tissue-based studies is limited. This multinational, multicenter pilot study aims to establish the groundwork for collaborative research on prostate cancer in sub-Saharan Africa.

METHODS

The Men of African Descent and Carcinoma of the Prostate network formed a pathologist working group representing eight institutions in five African countries. Formalin-fixed paraffin-embedded prostate tissue specimens were collected from Senegal, Nigeria, and Ghana. Histology slides were produced and digitally scanned. A central genitourinary pathologist (P.L.) and eight African general pathologists reviewed anonymized digital whole-slide images for International Society of Urological Pathology grade groups and other pathologic parameters. Discrepancies were re-evaluated, and consensus grading was assigned. A virtual training seminar on prostate cancer grading was followed by a second assessment on a subcohort of the same tissue set.

RESULTS

Of 134 tissue blocks, 133 had evaluable tissue; 13 lacked cancer evidence, and four were of insufficient quality. Post-training, interobserver agreement for grade groups improved to 56%, with a median Cohen's quadratic weighted kappa of 0.83 (mean, 0.74), compared with an initial 46% agreement and a quadratic weighted kappa of 0.77. Interobserver agreement between African pathologist groups was 40%, with a quadratic weighted kappa of 0.66 (95% CI, 0.51 to 0.76). African pathologists tended to overgrade (36%) more frequently than undergrade (18%) compared with the reference genitourinary pathologist. Interobserver variability tended to worsen with a decrease in tissue quality.

CONCLUSION

Tissue-based studies on prostate cancer in men of African descent are essential for a better understanding of this common disease. Standardized tissue handling protocols are crucial to ensure good tissue quality and data. The use of digital slide imaging can enhance collaboration among pathologists in multinational, multicenter studies.

Myeloid differentiation factor-2/LY96, a potential predictive biomarker of metastasis and poor outcomes in prostate cancer: clinical implications as a potential therapeutic target

Prostate cancer (CaP) is the most diagnosed cancer in males and the second leading cause of cancer deaths. Patients with localized tumors are generally curable. However, no curative treatment exists for patients with advanced and metastatic disease. Therefore, identifying critical proteins involved in the metastatic process would help to develop new therapeutic options for patients with advanced and aggressive CaP. We provide strong evidence that Myeloid differentiation factor-2 (MD2) plays a critical role in metastasis and CaP progression. Analysis of tumor genomic data showed that amplifications of MD2 and increased expression are associated with poor outcomes in patients. Immunohistochemistry analysis of tumor tissues showed a correlation between the expression of MD2 and cancer progression. The Decipher-genomic test validated the potential of MD2 in predicting metastasis. In vitro studies demonstrated that MD2 confers invasiveness by activating MAPK and NF-kB signaling pathways and inducing epithelial-mesenchymal transition. Furthermore, we show that metastatic cells release MD2 (sMD2). We measured serum-sMD2 in patients and found that the level is correlated to disease extent. We determined the significance of MD2 in metastasis in vivo and as a therapeutic target, showing that the molecular and pharmacological targeting of MD2 significantly inhibited metastasis in murine models. We conclude that MD2 predicts metastatic behavior, and serum-MD2 could be studied as a potential non-invasive biomarker for metastasis, whereas MD2 presence on prostate biopsy predicts adverse disease outcome. We suggest MD2-targeted therapies could be developed as potential treatments for aggressive metastatic disease.

Phenotype plasticity and altered sensitivity to chemotherapeutic agents in aggressive prostate cancer cells

In 2023, approximately 288,300 new diagnoses of prostate cancer will occur, with 34,700 disease-related deaths. Death from prostate cancer is associated with metastasis, enabled by progression of tumor phenotypes and successful extracapsular extension to reach Batson's venous plexus, a specific route to the spine and brain. Using a mouse-human tumor xenograft model, we isolated an aggressive muscle invasive cell population of prostate cancer, called DU145J7 with a distinct biophysical phenotype, elevated histone H3K27, and increased matrix metalloproteinase 14 expression as compared to the non-aggressive parent cell population called DU145WT. Our goal was to determine the sensitivities to known chemotherapeutic agents of the aggressive cells as compared to the parent population. High-throughput screening was performed with 5,578 compounds, comprising of approved and investigational drugs for oncology. Eleven compounds were selected for additional testing, which revealed that vorinostat, 5-azacitidine, and fimepinostat (epigenetic inhibitors) showed 2.6-to-7.5-fold increases in lethality for the aggressive prostate cancer cell population as compared to the parent, as judged by the concentration of drug to inhibit 50% cell growth (IC50). On the other hand, the DU145J7 cells were 2.2-to-4.0-fold resistant to mitoxantrone, daunorubicin, and gimatecan (topoisomerase inhibitors) as compared to DU145WT. No differences in sensitivities between cell populations were found for docetaxel or pirarubicin. The increased sensitivity of DU145J7 prostate cancer cells to chromatin modifying agents suggests a therapeutic vulnerability occurs after tumor cells invade into and through muscle. Future work will determine which epigenetic modifiers and what combinations will be most effective to eradicate early aggressive tumor populations.

Detection of extraprostatic extension by transperineal multiparametric magnetic resonance imaging-ultrasound fusion targeted combined with systemic template prostate biopsy

BACKGROUND

Extraprostatic extension (EPE) of prostate cancer (PCa) on transrectal (TR) needle core biopsy (Bx) is a rare histopathological finding that can help in clinical decision-making. The detection efficiency of the transperineal (TP) approach is yet to be explored.

METHODS

We retrospectively reviewed 2848 PCa cases using concomitant systemic template biopsy (SBx) and multiparametric magnetic resonance imaging (MRI)-ultrasound fusion-targeted biopsy (TBx) using the TR (n = 1917) or TP (n = 931) approach at our institution between January 2015 and July 2022. We assessed and compared clinical, MRI, and biopsy characteristics using different approaches (TP and TR) and methods (SBx and TBx).

RESULTS

In total, 40 EPE cases were identified (40/2848, 1.4%). TP showed a significantly higher EPE detection rate compared to TR in SBx (TR:0.7% vs. TP:1.6%; p = 0.028) and TBx (TR:0.5% vs. TP:1.2%; p = 0.033), as well as the combined methods (2.1% vs. 1.1%, p = 0.019). A significantly higher incidence of EPEs was found at non-base sites in TP than in TR (76.7% vs. 50%, p = 0.038). SBx showed a higher EPE detection rate than TBx; however, the difference was not statistically significant. TP showed higher prostate-specific antigen density (0.35 vs. 0.17, p = 0.005), higher frequency of GG4-5 in the cores with EPE (65.0% vs. 50.0%, p = 0.020), and more PCa-positive SBx cores (10 vs. 8, p = 0.023) compared to the TR.

CONCLUSIONS

TP may improve EPE detection compared with TR and should be applied to patients with adverse pre-biopsy features.

Myeloid differentiation factor-2/LY96, a new predictive biomarker of metastasis in prostate cancer: Clinical implications as a potential therapeutic target

Relapsed prostate cancer (CaP), usually treated with androgen deprivation therapy, acquires resistance to develop into lethal metastatic castration-resistant CaP. The cause of resistance remains elusive, and the lack of biomarkers predictive of castration-resistance emergence is a stumbling block in managing the disease. We provide strong evidence that Myeloid differentiation factor-2 (MD2) plays a critical role in metastasis and CaP progression. Analysis of tumor genomic data and IHC of tumors showed a high frequency of MD2 amplification and association with poor overall survival in patients. The Decipher-genomic test validated the potential of MD2 in predicting metastasis. In vitro studies demonstrated that MD2 confers invasiveness by activating MAPK and NF-kB signaling pathways. Furthermore, we show that metastatic cells release MD2 (sMD2). We measured serum-sMD2 in patients and found that the level is correlated to disease extent. We determined the significance of MD2 as a therapeutic target and found that targeting MD2 significantly inhibited metastasis in a murine model. We conclude that MD2 predicts metastatic behavior and serum-MD2 is a non-invasive biomarker for tumor burden, whereas MD2 presence on prostate biopsy predicts adverse disease outcome. We suggest MD2-targeted therapies could be developed as potential treatments for aggressive metastatic disease.

Significance of extraprostatic extension by Grade Groups 1-3 prostatic carcinoma on needle biopsy

BACKGROUND

It is rare for extraprostatic extension (EPE) on biopsy to be seen with Grade Groups (GG) 1-3 (Gleason scores 3 + 3 = 6; 3 + 4 = 7; 4 + 3 = 7) prostatic adenocarcinoma, and there is no data whether this finding should be a contraindication for performing radical prostatectomy (RP).

METHODS

Thirty eight cases with GG 1-3 prostatic adenocarcinoma as the highest grade in the case with EPE on biopsy were identified from our consultation files. Highly unfavorable findings at RP were those that if they could have been predicted preoperatively, might have factored into the decision of whether to proceed with surgery. For these purposes, highly unfavorable pathology at RP was defined as either the presence of seminal vesicle invasion or lymph node metastases or GG5 (Gleason score 9-10).

RESULTS

Among 37 patients with clinical follow-up data, 18 (49%) received radiation and/or hormonal therapy (RT/HT), 13 patients (35%) either underwent (n = 11) or are planning (n = 2) RP, and 6 patients (16%) received either ablation therapy or active surveillance. Based on the 11 RP pathology reports, 8 were GG2, one GG3 with tertiary pattern 5, and two GG3. Ten cases were reported to have EPE and six cases had positive margins. Only one had highly unfavorable pathology with pT3bN1 disease. The only difference between the RP and the RT/HT groups in their pretreatment parameters was the mean age of the RP patients was 61 compared with 69 for the RT/HT men (p = 0.02); the lack of many cases with highly unfavorable pathology at RP cannot be attributable to a selection bias of men with lower volume cancer on biopsy or lower serum prostate-specific antigen levels choosing RP over RT/HT.

CONCLUSIONS

Despite EPE on biopsy, most men do not have highly unfavorable pathology at RP, and this treatment should remain an option in this setting.

Clinical and oncologic findings of extraprostatic extension on needle biopsy in de novo metastatic prostate cancer

This study aimed to explore the clinical and oncologic findings in patients with de novo metastatic prostate cancer (mPCa) and extraprostatic extension (EPE) on biopsy. We retrospectively evaluated data on 630 patients with de novo mPCa between January 2009 and December 2017 in the West China Hospital (Chengdu, China), including evaluating the relationships between EPE and other variables and the association of EPE with survival outcomes by the Chi-square test, Kaplan-Meier curves, and the Cox proportional-hazards model. EPE was found in 70/630 patients, making a prevalence of 11.1%. The presence of EPE on biopsy was associated with higher Gleason scores and higher incidence of neuroendocrine differentiation (NED), intraductal carcinoma of the prostate (IDC-P), and perineural invasion (PNI). Compared with those without EPE, patients with EPE had shorter castration-resistant prostate cancer-free survival (CFS; median: 14.1 vs 17.1 months, P = 0.015) and overall survival (OS; median: 43.7 vs 68.3 months, P = 0.032). According to multivariate analysis, EPE was not an independent predictor for survival. Subgroup analyses demonstrated that patients with favorable characteristics, including negative NED or IDC-P status, Eastern Cooperative Oncology Group (ECOG) score <2, and prostate-specific antigen (PSA) <50 ng ml^-1, had worse prognoses if EPE was detected. In patients with PSA <50 ng ml^-1, EPE was a negative independent predictor for OS (hazard ratio [HR]: 4.239, 95% confidence interval [CI]: 1.218-14.756, P = 0.023). EPE was strongly associated with other aggressive clinicopathological features and poorer CFS and OS. These data suggest that EPE may be an indicator of poor prognosis, particularly in patients, otherwise considered likely to have favorable survival outcomes.

Cohesive cancer invasion of the biophysical barrier of smooth muscle

Smooth muscle is found around organs in the digestive, respiratory, and reproductive tracts. Cancers arising in the bladder, prostate, stomach, colon, and other sites progress from low-risk disease to high-risk, lethal metastatic disease characterized by tumor invasion into, within, and through the biophysical barrier of smooth muscle. We consider here the unique biophysical properties of smooth muscle and how cohesive clusters of tumor use mechanosensing cell-cell and cell-ECM (extracellular matrix) adhesion receptors to move through a structured muscle and withstand the biophysical forces to reach distant sites. Understanding integrated mechanosensing features within tumor cluster and smooth muscle and potential triggers within adjacent adipose tissue, such as the unique damage-associated molecular pattern protein (DAMP), eNAMPT (extracellular nicotinamide phosphoribosyltransferase), or visfatin, offers an opportunity to prevent the first steps of invasion and metastasis through the structured muscle.

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.

Identifying and treating ROBO1-ve /DOCK1+ve prostate cancer: An aggressive cancer subtype prevalent in African American patients

BACKGROUND

There is a need to develop novel therapies which could be beneficial to patients with prostate cancer (CaP) including those who are predisposed to poor outcome, such as African-Americans. This study investigates the role of ROBO1-pathway in predicting outcome and race-based disparity in patients with CaP.

METHODS AND RESULTS

Aided by RNA sequencing-based DECIPHER-testing and immunohistochemical (IHC) analysis of tumors we show that ROBO1 is lost during the progressive stages of CaP, a prevalent feature in African-Americans. We show that the loss of ROBO1 predicts high-risk of recurrence, metastasis and poor outcome of androgen-deprivation therapy in radical prostatectomy-treated patients. These data identified an aggressive ROBO1deficient /DOCK1+ve sub-class of CaP. Combined genetic and IHC data showed that ROBO1 loss is accompanied by DOCK1/Rac1 elevation in grade-III/IV primary-tumors and Mets. We observed that the hypermethylation of ROBO1-promoter contributes to loss of expression that is highly prevalent in African-Americans. Because of limitations in restoring ROBO1 function, we asked if targeting the DOCK1 could be an ideal strategy to inhibit progression or treat ROBO1deficient metastatic-CaP. We tested the pharmacological efficacy of CPYPP, a selective inhibitor of DOCK1 under in vitro and in vivo conditions. Using ROBO1-ve and ROBO1+ve CaP models, we determined the median effective concentration of CPYPP for growth. DOCK1-inhibitor treatment significantly decreased the (a) Rac1-GTP/β-catenin activity, (b) transmigration of ROBO1deficient cells across endothelial lining, and (c) metastatic spread of ROBO1deficient cells through the vasculature of transgenicfl Zebrafish model.

CONCLUSION

We suggest that ROBO1 status forms as predictive biomarker of outcome in high-risk populations such as African-Americans and DOCK1-targeting therapy has a clinical potential for treating metastatic-CaP.

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.