Expression Analysis and Mutational Status of Histone Methyltransferase KMT2D at Different Upper Tract Urothelial Carcinoma Locations

The gene coding for histone methyltransferase KMT2D is found among the top mutated genes in upper tract urothelial carcinoma (UTUC); however, there is a lack of data regarding its association with clinicopathologic features as well as survival outcomes. Therefore, we aimed to investigate KMT2D expression, mutation patterns, and their utility as prognostic biomarkers in patients with UTUC. A single-center study was conducted on tumor specimens from 51 patients treated with radical nephroureterectomy (RNU). Analysis of KMT2D protein expression was performed using immunohistochemistry (IHC). Customized next-generation sequencing (NGS) was used to assess alterations in KMT2D exons. Cox regression was used to assess the relationship of KMT2D protein expression and mutational status with survival outcomes. KMT2D expression was increased in patients with a previous history of bladder cancer (25% vs. 0%, p = 0.02). The NGS analysis of KMT2D exons in 27 UTUC tumors revealed a significant association between pathogenic KMT2D variants and tumor location (p = 0.02). Pathogenic KMT2D variants were predominantly found in patients with non-pelvic or multifocal tumors (60% vs. 14%), while the majority of patients with a pelvic tumor location (81% vs. 20%) did not harbor pathogenic KMT2D alterations. Both IHC and NGS analyses of KMT2D failed to detect a statistically significant association between KMT2D protein or KMT2D gene alteration status and clinical variables such as stage/grade of the disease or survival outcomes (all p > 0.05). KMT2D alterations and protein expression were associated with UTUC features such as multifocality, ureteral location, and previous bladder cancer. While KMT2D protein expression and KMT2D mutational status do not seem to have prognostic value in UTUC, they appear to add information to improve clinical decision-making regarding the type of therapy.

Supervised machine learning enables non-invasive lesion characterization in primary prostate cancer with [68Ga]Ga-PSMA-11 PET/MRI

PURPOSE

Risk classification of primary prostate cancer in clinical routine is mainly based on prostate-specific antigen (PSA) levels, Gleason scores from biopsy samples, and tumor-nodes-metastasis (TNM) staging. This study aimed to investigate the diagnostic performance of positron emission tomography/magnetic resonance imaging (PET/MRI) in vivo models for predicting low-vs-high lesion risk (LH) as well as biochemical recurrence (BCR) and overall patient risk (OPR) with machine learning.

METHODS

Fifty-two patients who underwent multi-parametric dual-tracer [18F]FMC and [68Ga]Ga-PSMA-11 PET/MRI as well as radical prostatectomy between 2014 and 2015 were included as part of a single-center pilot to a randomized prospective trial (NCT02659527). Radiomics in combination with ensemble machine learning was applied including the [68Ga]Ga-PSMA-11 PET, the apparent diffusion coefficient, and the transverse relaxation time-weighted MRI scans of each patient to establish a low-vs-high risk lesion prediction model (MLH). Furthermore, MBCR and MOPR predictive model schemes were built by combining MLH, PSA, and clinical stage values of patients. Performance evaluation of the established models was performed with 1000-fold Monte Carlo (MC) cross-validation. Results were additionally compared to conventional [68Ga]Ga-PSMA-11 standardized uptake value (SUV) analyses.

RESULTS

The area under the receiver operator characteristic curve (AUC) of the MLH model (0.86) was higher than the AUC of the [68Ga]Ga-PSMA-11 SUVmax analysis (0.80). MC cross-validation revealed 89% and 91% accuracies with 0.90 and 0.94 AUCs for the MBCR and MOPR models respectively, while standard routine analysis based on PSA, biopsy Gleason score, and TNM staging resulted in 69% and 70% accuracies to predict BCR and OPR respectively.

CONCLUSION

Our results demonstrate the potential to enhance risk classification in primary prostate cancer patients built on PET/MRI radiomics and machine learning without biopsy sampling.

Thyroid and androgen receptor signaling are antagonized by μ-Crystallin in prostate cancer

Androgen deprivation therapy (ADT) remains a key approach in the treatment of prostate cancer (PCa). However, PCa inevitably relapses and becomes ADT resistant. Besides androgens, there is evidence that thyroid hormone thyroxine (T4) and its active form 3,5,3'-triiodo-L-thyronine (T3) are involved in the progression of PCa. Epidemiologic evidences show a higher incidence of PCa in men with elevated thyroid hormone levels. The thyroid hormone binding protein μ-Crystallin (CRYM) mediates intracellular thyroid hormone action by sequestering T3 and blocks its binding to cognate receptors (TRα/TRβ) in target tissues. We show in our study that low CRYM expression levels in PCa patients are associated with early biochemical recurrence and poor prognosis. Moreover, we found a disease stage-specific expression of CRYM in PCa. CRYM counteracted thyroid and androgen signaling and blocked intracellular choline uptake. CRYM inversely correlated with [18F]fluoromethylcholine (FMC) levels in positron emission tomography/magnetic resonance imaging of PCa patients. Our data suggest CRYM as a novel antagonist of T3- and androgen-mediated signaling in PCa. The role of CRYM could therefore be an essential control mechanism for the prevention of aggressive PCa growth.

Discovery of Molecular DNA Methylation-Based Biomarkers through Genome-Wide Analysis of Response Patterns to BCG for Bladder Cancer

Background: Bacillus Calmette-Guérin (BCG) immunotherapy, the standard adjuvant intravesical therapy for some intermediate and most high-risk non-muscle invasive bladder cancers (NMIBCs), suffers from a heterogenous response rate. Molecular markers to help guide responses are scarce and currently not used in the clinical setting. Methods: To identify novel biomarkers and pathways involved in response to BCG immunotherapy, we performed a genome-wide DNA methylation analysis of NMIBCs before BCG therapy. Genome-wide DNA methylation profiles of DNA isolated from tumors of 26 BCG responders and 27 failures were obtained using the Infinium MethylationEPIC BeadChip. Results: Distinct DNA methylation patterns were found by genome-wide analysis in the two groups. Differentially methylated CpG sites were predominantly located in gene promoters and gene bodies associated with bacterial invasion of epithelial cells, chemokine signaling, endocytosis, and focal adhesion. In total, 40 genomic regions with a significant difference in methylation between responders and failures were detected. The differential methylation state of six of these regions, localized in the promoters of the genes GPR158, KLF8, C12orf42, WDR44, FLT1, and CHST11, were internally validated by bisulfite-sequencing. GPR158 promoter hypermethylation was the best predictor of BCG failure with an AUC of 0.809 (p-value < 0.001). Conclusions: Tumors from BCG responders and BCG failures harbor distinct DNA methylation profiles. Differentially methylated DNA regions were detected in genes related to pathways involved in bacterial invasion of cells or focal adhesion. We identified candidate DNA methylation biomarkers that may help to predict patient prognosis after external validation in larger, well-designed cohorts.

Dissection of primary prostate cancer to determine the clonal origin of synchronous lymph node metastasis

e17614

Background: Primary prostate cancer often consists of multiple, genomically-distinct clones. The clonal source of lymph node metastasis in multifocal disease is unknown. We sought to analyze and determine the histopathologic and molecular characteristics of the tumor sub-clones capable of metastasis in primary prostate cancers with synchronous lymph node metastasis. Methods: We identified patients with primary prostate cancer found to have lymph node (LN) metastasis at the time of radical prostatectomy, including those with multifocal disease. Punch biopsies were obtained from multiple regions of primary tumors and LN metastases. Targeted next generation sequencing to assess somatic DNA mutations, copy number alterations (CNA), and TMPRSS2:ERG fusion status. Bioinformatic analyses were performed using in-house developed pipelines. Phylogenetic evolutionary analyses were performed to delineate the primary cancer clone responsible for LN metastasis. Results: We identified 2 patients with LN cancer regions. In one patient, while all four Grade Group (GG) 5 primary tumor (PT) regions showed concordant TP53 and TPR non-synonymous mutations and broad copy number alterations (CNAs) with two LN foci, only two regions shared high level CNAs with both lymph node foci. In this case, a GG1 tumor focus showed no TP53 somatic mutation or CNA overlap with the high-grade tumor or lymph node samples. Critically, phylogenetic analysis revealed that the GG5 PT with extra-prostatic extension (EPE) showed higher concordance with the LN metastases than regions confined to the prostate. In another patient with four PT, phylogenetic analysis revealed that the PT with EPE closely resembled the LN metastasis; both were TMPRSS2:ERG fusion positive share PTEN copy number loss. Two PT (GG1 and 2) appeared to be independent clones and were TMPRSS2:ERG fusion negative. One of the six circulating tumor cells (isolated pre-prostatectomy) from this patient demonstrated a significant PTEN copy loss consistent with the findings in the region of EPE and the LN metastasis. Conclusions: Our findings confirm molecular heterogeneity of primary prostate cancers and homogeneity of LN metastases supporting the use of shared molecular alterations to infer clonal lineage. Our results highlight the critical role of adverse pathologic features, such as grade and EPE, in prostate cancer with synchronous lymph node metastasis.

The prognostic impact of tumour NSD2 expression in advanced prostate cancer

Purpose: To assess the prognostic significance of the nuclear receptor binding SET protein 2 (NSD2), a co-activator of the NFkB-pathway, on tumour progression in patients with advanced prostate cancer (PCa).Methods: We retrospectively assessed NSD2 expression in 53 patients with metastatic and castration-resistant PCa. Immunohistochemical staining for NSD2 was carried out on specimen obtained from palliative resection of the prostate. Univariable and multivariable analyses were performed to assess the association between NSD2 expression and PCa progression.Results: Of the 53 patients, 41 had castration-resistant PCa and 48 men had metastases at time of tissue acquisition. NSD2 expression was increased in tumour specimen from 42 patients (79.2%). In univariable Cox regression analyses, NSD2 expression was associated with PSA progression, progression on imaging and overall survival (p = 0.04, respectively). In multivariable analyses, NSD2 expression did not retain its association with these endpoints.Conclusions: NSD2 expression is abnormal in almost 80% of patients with advanced PCa. Expression levels of this epigenetic regulator are easily detected by immunohistochemistry while this biomarker exhibited prognostic value for PCa progression and death in univariable analysis. Further studies on NSD2 involvement in PCa proliferation, progression, metastasis and resistance mechanisms are needed.

Can the addition of clinical information improve the accuracy of PI-RADS version 2 for the diagnosis of clinically significant prostate cancer in positive MRI?

AIM

To report prostate cancer (PCa) prevalence in Prostate Imaging Reporting and Data System version 2 (PI-RADS v2) categories and investigate the potential to avoid unnecessary, magnetic resonance imaging (MRI)-guided in-bore biopsies by adding clinical and biochemical patient characteristics.

MATERIALS AND METHODS

The present institutional review board-approved, prospective study on 137 consecutive men with 178 suspicious lesions on 3 T MRI was performed. Routine data collected for each patient included patient characteristics (age, prostate volume), clinical background information (prostate-specific antigen [PSA] levels, PSA density), and PI-RADS v2 scores assigned in a double-reading approach.

RESULTS

Histopathological evaluation revealed a total of 93/178 PCa (52.2%). The mean age was 66.3 years and PSA density was 0.24 ng/ml² (range, 0.04-0.89 ng/ml). Clinically significant PCa (csPCa, Gleason score >6) was confirmed in 50/93 (53.8%) lesions and was significantly associated with higher PI-RADS v2 scores (p=0.0044). On logistic regression analyses, age, PSA density, and PI-RADS v2 scores contributed independently to the diagnosis of csPCa (p=7.9×10^-7, p=0.097, and p=0.024, respectively). The resulting area under the receiver operating characteristic curve (AUC) to predict csPCa was 0.76 for PI-RADS v2, 0.59 for age, and 0.67 for PSA density. The combined regression model yielded an AUC of 0.84 for the diagnosis of csPCa and was significantly superior to each single parameter (p≤0.0009, respectively). Unnecessary biopsies could have been avoided in 50% (64/128) while only 4% (2/50) of csPCa lesions would have been missed.

CONCLUSIONS

Adding age and PSA density to PI-RADS v2 scores improves the diagnostic accuracy for csPCa. A combination of these variables with PI-RADS v2 can help to avoid unnecessary in-bore biopsies while still detecting the majority of csPCa.

Urinary expression of genes involved in DNA methylation and histone modification for diagnosis of bladder cancer in patients with asymptomatic microscopic haematuria

The aim of the present study was to identify and test a urine marker panel of genes involved in DNA methylation and histone modification for the detection of urothelial carcinoma of the bladder (UCB). RNA samples obtained from the voided urine of 227 patients with asymptomatic microscopic haematuria (AMH) were analysed. Gene array analysis was performed on 18 randomly selected cDNA samples, which revealed that histone deacetylase 9 (HDAC9), HDAC3, tRNA (cytosine-5-)-methyltransferase1 and DNA methyltransferase 1 were differentially expressed between patients with UCB and control subjects. Subsequently, reverse transcription-quantitative polymerase chain reaction analysis was employed to test the performance of the identified four-gene panel on the remaining 209 cDNA samples. In this targeted discovery cohort, all four genes were significantly associated with UCB on univariable analyses [each odds ratio (OR) >2, P<0.05], but only HDAC3 was significant following multivariable analysis (OR=2.8, P=0.011). The addition of HDAC3 to a base risk factor model improved its accuracy by 1.4%. These data suggest that urinary HDAC3 is associated with the presence of UCB in patients with AMH; however, HDAC3 improved the accuracy of the established risk factors only to a marginal extent.

Transcriptomic heterogeneity in multifocal prostate cancer

BACKGROUND

Commercial gene expression assays are guiding clinical decision making in patients with prostate cancer, particularly when considering active surveillance. Given heterogeneity and multifocality of primary prostate cancer, such assays should ideally be robust to the coexistence of unsampled higher grade disease elsewhere in the prostate in order to have clinical utility. Herein, we comprehensively evaluated transcriptomic profiles of primary multifocal prostate cancer to assess robustness to clinically relevant multifocality.

METHODS

We designed a comprehensive, multiplexed targeted RNA-sequencing assay capable of assessing multiple transcriptional classes and deriving commercially available prognostic signatures, including the Myriad Prolaris Cell Cycle Progression score, the Oncotype DX Genomic Prostate Score, and the GenomeDX Decipher Genomic Classifier. We applied this assay to a retrospective, multi-institutional cohort of 156 prostate cancer samples. Derived commercial biomarker scores for 120 informative primary prostate cancer samples from 44 cases were determined and compared.

RESULTS

Derived expression scores were positively correlated with tumor grade (rS = 0.53-0.73; all P < 0.001), both within the same case and across the entire cohort. In cases of extreme grade-discordant multifocality (co-occurrence of grade group 1 [GG1] and ≥GG4 foci], gene expression scores were significantly lower in low- (GG1) versus high-grade (≥GG4) foci (all P < 0.001). No significant differences in expression scores, however, were observed between GG1 foci from prostates with and without coexisting higher grade cancer (all P > 0.05).

CONCLUSIONS

Multifocal, low-grade and high-grade prostate cancer foci exhibit distinct prognostic expression signatures. These findings demonstrate that prognostic RNA expression assays performed on low-grade prostate cancer biopsy tissue may not provide meaningful information on the presence of coexisting unsampled aggressive disease.

FUNDING

Prostate Cancer Foundation, National Institutes of Health (U01 CA214170, R01 CA183857, University of Michigan Prostate Specialized Program of Research Excellence [S.P.O.R.E.] P50 CA186786-05, Weill Cornell Medicine S.P.O.R.E. P50 CA211024-01A1), Men of Michigan Prostate Cancer Research Fund, University of Michigan Comprehensive Cancer Center core grant (2-P30-CA-046592-24), A. Alfred Taubman Biomedical Research Institute, and Department of Defense.

A urinary microRNA (miR) signature for diagnosis of bladder cancer

INTRODUCTION

Bladder cancer (BC) is diagnosed by cystoscopy, which is invasive, costly and causes considerable patient discomfort. MicroRNAs (miR) are dysregulated in BC and may serve as non-invasive urine markers for primary diagnostics and monitoring. The purpose of this study was to identify a urinary miR signature that predicts the presence of BC.

METHODS

For the detection of potential urinary miR markers, expression of 384 different miRs was analyzed in 16 urine samples from BC patients and controls using a Taqman™ Human MicroRNA Array (training set). The identified candidate gene signature was subsequently validated in an independent cohort of 202 urine samples of patients with BC and controls with microscopic hematuria. The final miR signature was developed from a multivariable logistic regression model.

RESULTS

Analysis of the training set identified 14 candidate miRs for further analysis within the validation set. Using backward stepwise elimination, we identified a subset of 6 miRs (let-7c, miR-135a, miR-135b, miR-148a, miR-204, miR-345) that distinguished BC from controls with an area under the curve of 88.3%. The signature was most accurate in diagnosing high-grade non-muscle invasive BC (area under the curve = 92.9%), but was capable to identify both low-grade and high-grade disease as well as non-muscle and muscle-invasive BC with high accuracies.

CONCLUSIONS

We identified a 6-gene miR signature that can accurately predict the presence of BC from urine samples, independent of stage and grade. This signature represents a simple urine assay that may help reducing costs and morbidity associated with invasive diagnostics.

PSMA Ligand PET/MRI for Primary Prostate Cancer: Staging Performance and Clinical Impact

PURPOSE

Primary staging of prostate cancer relies on modalities, which are limited. We evaluate simultaneous [⁶⁸Ga]Ga-PSMA-11 PET (PSMA-PET)/MRI as a new diagnostic method for primary tumor-node-metastasis staging compared with histology and its impact on therapeutic decisions.

EXPERIMENTAL DESIGN

We investigated 122 patients with PSMA-PET/MRI prior to planned radical prostatectomy (RP). Primary endpoint was the accuracy of PSMA-PET/MRI in tumor staging as compared with staging-relevant histology. In addition, a multidisciplinary team reassessed the initial therapeutic approach to evaluate its impact on the therapeutic management.

RESULTS

PSMA-PET/MRI correctly identified prostate cancer in 119 of 122 patients (97.5%). Eighty-one patients were treated with RP and pelvic lymphadenectomy. The accuracy for T staging was 82.5% [95% confidence interval (CI), 73-90; P < 0.001], for T2 stage was 85% (95% CI, 71-94; P < 0.001), for T3a stage was 79% (95% CI, 43-85; P < 0.001), for T3b stage was 94% (95% CI, 73-100; P < 0.001), and for N1 stage was 93% (95% CI, 84-98; P < 0.001). PSMA-PET/MRI changed the therapeutic strategy in 28.7% of the patients with either the onset of systemic therapy/radiotherapy (n = 16) or active surveillance (n = 19).

CONCLUSIONS

PSMA-PET/MRI can provide an accurate staging of newly diagnosed prostate cancer. In addition, treatment strategies were changed in almost a third of the patients due to the information of this hybrid imaging technique.

Abstract B036: Comprehensive transcriptomic profiling challenges the robustness of prostate cancer prognostic signatures to multifocality

Purpose: Imaging and tissue-based biomarkers are increasingly utilized in men diagnosed with low-grade prostate cancer (PCa) to guide definitive management vs. active surveillance. PCa is uniquely multifocal, with multiple clonally distinct tumor foci present in the majority of men. A single tumor focus may also be composed of both low- and high-grade components. Hence, an ideal prognostic biomarker should be robust to both undersampling of a high-grade component, as well as a not sampled multifocal high-grade tumor focus.

Materials and Methods: To assess the robustness of prognostic biomarkers to multifocality, we designed a comprehensive multiplexed targeted RNA sequencing assay (mxRNAseq) capable of assessing multiple classes of transcriptional alterations and deriving available prognostic signature scores (e.g., Prolaris CCP and OncotypeDX GPS). We applied this assay to a retrospective, multi-institution cohort of over 150 formalin-fixed, paraffin-embedded tissue samples representing the range of prostate cancer progression. Single candidate biomarkers and derived prognostic signatures were compared between low-grade foci in cases with and without high-grade foci, all-low-grade foci vs. all-high-grade foci, and cases with extremes of grade differences in multifocal tumors. Frequency of clinically relevant extreme multifocality was determined by identifying patients in a single-institution consecutive prostatectomy database over 9 years who had exclusively low-grade cancer on biopsy but very-high-grade disease on prostatectomy.

Results: Our mxRNAseq assay robustly detected known coding gene/lncRNA expression, gene fusions and splice variants, and expressed mutations and germline variants. Supervised hierarchical clustering of target gene expression confirmed expected transcriptional module deregulation and derived prognostic signatures across prostate cancer progression. Prognostic biomarkers (including derived signatures) showed no significant differences in expression between low-grade foci from prostates with and without high-grade multifocal tumors and were uniformly higher in high-grade foci vs. low-grade foci from the same case. In four cases of extreme multifocality (Gleason score 6 vs. &gt;=8 foci), prognostic signatures were significantly lower in low-grade foci vs. high-grade foci. In 1,418 men with biopsy Gleason score 3+3=6 or 3+4=7, 21 (1.5%) had Gleason score ≥ 4+4=8, where the biopsy almost certainly did not sample the most clinically relevant focus.

Conclusions: Using a novel comprehensive mxRNAseq assay, our results challenge the robustness of prognostic biomarkers between multifocal low- and high-grade prostate cancer foci. Tissue-based prostate cancer prognostic biomarkers should be specifically validated using an extreme multifocality design to support utility in predicting the presence of an unsampled, aggressive multifocal tumor focus.

Citation Format: Simpa Salami, Daniel H. Hovelson, Jeremy B. Kaplan, Romain Mathieu, Aaron M. Udager, Nicole Curci, Matthew Lee, Lorena Lazo de la Vega, Martin Susani, Nathalie Rioux-Leclercq, Daniel E. Spratt, Todd M. Morgan, Matthew S. Davenport, Mark A. Rubin, Shariat F. Shahrokh, Scott A. Tomlins, Ganesh S. Palapattu. Comprehensive transcriptomic profiling challenges the robustness of prostate cancer prognostic signatures to multifocality [abstract]. In: Proceedings of the AACR Special Conference: Prostate Cancer: Advances in Basic, Translational, and Clinical Research; 2017 Dec 2-5; Orlando, Florida. Philadelphia (PA): AACR; Cancer Res 2018;78(16 Suppl):Abstract nr B036.

Accurate prediction of progression to muscle-invasive disease in patients with pT1G3 bladder cancer: A clinical decision-making tool

PURPOSE

To improve current prognostic models for the selection of patients with T1G3 urothelial bladder cancer who are more likely to fail intravesical therapy and progress to muscle-invasive bladder cancer (MIBC).

MATERIALS AND METHODS

We performed a retrospective analysis of 1,289 patients with pT1G3 urothelial bladder cancer who were treated with transurethral resection of the bladder (TURB) and adjuvant intravesical bacillus-Calmette-Guérin (BCG). Random-split sample data and competing-risk regression were used to identify the independent impact of lymphovascular invasion (LVI) and variant histology (VH) on progression to MIBC. We developed a nomogram for predicting patient-specific probability of disease progression at 2 and 5 years after TURB. Decision curve analysis (DCA) was performed to evaluate the clinical benefit associated with the use of our nomogram.

RESULTS

In the development cohort, within a median follow-up of 51.6 months (IQR: 19.3-92.5), disease progression occurred in 89 patients (13.8%). A total of 84 (13%) patients were found to have VH and 57 (8.8%) with LVI at TURB. Both factors were independently associated with disease progression on multivariable competing-risk analysis (HR: 4.4; 95% CI: 2.8-6.9; P<0.001 and HR: 3.5; 95% CI: 2.1-5.8; P<0.001, respectively). DCA showed superior net benefits for the nomogram within a threshold probability of progression between 5% and 55%. Limitations are inherent to the retrospective design.

CONCLUSIONS

We demonstrated the clinical value of the integration of LVI and VH in a prognostic model for the prediction of MIBC. Indeed, our tool provides superior individualized risk estimation of progression facilitating decision-making regarding early RC.

Integrative molecular profiling challenges robustness of prognostic signature scores in multifocal prostate cancer

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Background: Tissue based biomarkers are increasingly utilized in men diagnosed with low grade prostate cancer (PCa) to guide definitive management vs. active surveillance. PCa is uniquely multifocal, suggesting ideal prognostic biomarkers should be robust to both undersampling of a high grade component of a mixed-grade tumor focus, as well as unsampled multifocal high grade tumor foci. Methods: To assess the robustness of prognostic biomarkers to multifocality, we designed a comprehensive multiplexed targeted RNA sequencing assay (mxRNAseq) capable of assessing multiple classes of transcriptional alterations and deriving available prognostic signature scores (e.g. Prolaris CCP and OncotypeDX GPS). We applied this assay to a retrospective cohort of 176 FFPE tissue samples representing the range of PCa progression. Single candidate biomarkers and derived prognostic signatures were analyzed in multifocal cases with only low-grade disease as well as those with extreme grade differences across tumor foci. Results: Our mxRNAseq assay robustly detected known coding gene/lncRNA expression, gene fusions, splice variants, and expressed somatic and germline mutations. Supervised clustering of target gene expression confirmed expected transcriptional module deregulation and derived prognostic signatures across PCa progression. Prognostic biomarkers (including derived signatures) showed no significant expression differences between low grade foci from prostates with and without high grade disease foci and were uniformly higher in high vs. low grade foci from the same case. In four cases of extreme multifocality (Gleason score 6 vs. ≥ 8 foci), prognostic signatures were significantly lower in low vs. high grade foci. In a clinical prostatectomy cohort of 1,418 men with diagnostic biopsy Gleason score 3+3 = 6 or 3+4 = 7, 21 (1.5%) had Gleason score ≥ 4+4 = 8, suggesting the initial biopsy missed or undersampled the most clinically relevant focus. Conclusions: Using a novel comprehensive mxRNAseq assay, our results challenge the robustness of prognostic biomarkers between multifocal low and high grade PCa foci, critically important in the context of un/under-sampled aggressive tumor foci.

3D T2-weighted imaging to shorten multiparametric prostate MRI protocols

Objectives

To determine whether 3D acquisitions provide equivalent image quality, lesion delineation quality and PI-RADS v2 performance compared to 2D acquisitions in T2-weighted imaging of the prostate at 3 T.

Methods

This IRB-approved, prospective study included 150 consecutive patients (mean age 63.7 years, 35–84 years; mean PSA 7.2 ng/ml, 0.4–31.1 ng/ml). Two uroradiologists (R1, R2) independently rated image quality and lesion delineation quality using a five-point ordinal scale and assigned a PI-RADS score for 2D and 3D T2-weighted image data sets. Data were compared using visual grading characteristics (VGC) and receiver operating characteristics (ROC)/area under the curve (AUC) analysis.

Results

Image quality was similarly good to excellent for 2D T2w (mean score R1, 4.3 ± 0.81; R2, 4.7 ± 0.83) and 3D T2w (mean score R1, 4.3 ± 0.82; R2, 4.7 ± 0.69), p = 0.269. Lesion delineation was rated good to excellent for 2D (mean score R1, 4.16 ± 0.81; R2, 4.19 ± 0.92) and 3D T2w (R1, 4.19 ± 0.94; R2, 4.27 ± 0.94) without significant differences (p = 0.785). ROC analysis showed an equivalent performance for 2D (AUC 0.580–0.623) and 3D (AUC 0.576–0.629) T2w (p > 0.05, respectively).

Conclusions

Three-dimensional acquisitions demonstrated equivalent image and lesion delineation quality, and PI-RADS v2 performance, compared to 2D in T2-weighted imaging of the prostate. Three-dimensional T2-weighted imaging could be used to considerably shorten prostate MRI protocols in clinical practice.

Key points

• 3D shows equivalent image quality and lesion delineation compared to 2D T2w.

• 3D T2w and 2D T2w image acquisition demonstrated comparable diagnostic performance.

• Using a single 3D T2w acquisition may shorten the protocol by 40%.

• Combined with short DCE, multiparametric protocols of 10 min are feasible.

Prostate-specific Antigen Parameters and Prostate Health Index Enhance Prostate Cancer Prediction With the In-bore 3-T Magnetic Resonance Imaging-guided Transrectal Targeted Prostate Biopsy After Negative 12-Core Biopsy

OBJECTIVE

To assess prostate cancer (PCa) detection and prediction by combining the in-bore magnetic resonance imaging-guided transrectal targeted prostate biopsy (MRGB) with prostate-specific antigen (PSA) parameters and the Prostate Health Index (PHI) in case of negative 12-core standard biopsy.

MATERIALS AND METHODS

A total of 112 men (2014-2016) underwent 3-T multiparametric magnetic resonance imaging and subsequent MRGB of Prostate Imaging-Reporting and Data System (PI-RADS) lesions 3-5. Ancillary PSA parameters (PSA ratio [%fPSA] and PSA density [PSAD]) and the PHI and PHI density (PHID) were recorded. With these parameters in combination with MRGB, PCa prediction was calculated.

RESULTS

The most common lesions biopsied were PI-RADS 4 (66%), located in the peripheral zone (64%), in the middle (58%) and anterior (65%) sections of the prostate, and 13 mm (IQR 10-15) in size. PCa was found in 62 (55%) patients (28% Gleason score ≥7). PSAD (0.15 vs 0.21; P = .0051), %fPSA (16 vs 13; P = .0191), PHI (45 vs 69; P < .0001), PHID (0.7 vs 1.5; P < .0001), and prostate volume (56 mL vs 45 mL; P = .0073) were significantly different in patients with PCa and those without PCa. PHI and PHID were the strongest predictors of PCa with areas under the curve of 0.79 and 0.77, respectively. Using optimal thresholds of 59 and 0.79, PHI and PHID were 69% and 84% sensitive and 82% and62% specific for PCa, respectively.

CONCLUSION

Following negative standard biopsy of the prostate, the MRGB achieved an overall PCa detection rate of 55% in patients with PI-RADS 3-5 lesions. By considering PHI and PHID, 82% and 62% of unnecessary biopsies could have been avoided, failing to detect 31% and 16% of cancers.

Impact of the Level of Urothelial Carcinoma Involvement of the Prostate on Survival after Radical Cystectomy

Objective:

Urothelial prostatic involvement (UPI) at the time of radical cystoprostatectomy (RCP) was found associated with worse survival outcomes by several previous reports. Our aim is to evaluate the impact of different levels of UPI on survival outcomes using a large series of male patients treated with RCP.

Methods:

Whole step section specimens from 995 male BCa patients were assessed for UPI defined as: no involvement vs. prostatic urethral carcinoma in situ (CIS) vs. lamina propria involvement vs. ductal CIS vs. prostate stromal involvement. Primary end point of the study was predictors of prostatic involvement at RCP and its impact on overall survival after surgery.

Results:

Prostatic involvement was recorded in 307 (30.9%) patients: 28% with prostatic urethral CIS, 12% with lamina propria involvement, 13% with ductal CIS and 47% with stromal involvement. Median follow-up was 70 months. Patients with stromal involvement had a worse 5-year survival (12%) than those with prostatic urethra CIS (40%), lamina propria involvement (36%), and ductal CIS (35%). Considering predictors of prostatic involvement, multifocal tumor (Odds Ratio [OR]: 6.60, p < 0.001), lymphovascular invasion (OR: 2.61, p < 0.001), lymph node metastases (OR: 2.02, p < 0.001) and CIS (OR: 2.02, p < 0.001) were found associated. Similar predictors were found assessing stromal involvement.

Conclusions

Approximately one third of RCP patients harbor prostatic involvement of urothelial carcinoma. While all UPI are associated with worse overall survival, stromal involvement confers the worst outcome supporting its classification as T4 in the TNM staging.

Multiparametric [11C]Acetate positron emission tomography-magnetic resonance imaging in the assessment and staging of prostate cancer

Background

The aim of this study was to evaluate whether MP [¹¹C]Acetate PET-MRI enables an accurate differentiation of benign and malignant prostate tumors as well as local and distant staging.

Materials and methods

Fifty-six consecutive patients fulfilling the following criteria were included in this IRB-approved prospective study: elevated PSA levels or suspicious findings at digital rectal examination or TRUS; and histopathological verification. All patients underwent MP [¹¹C]Acetate PET-MRI of the prostate performed on separate scanners with PET/CT using [¹¹C]Acetate and 3T MP MR imaging. Appropriate statistical tests were used to determine diagnostic accuracy, local and distant staging.

Results

MP imaging with two MRI parameters (T2w and DWI) achieved the highest sensitivity, specificity, and diagnostic accuracy of 95%, 68.8%, and 88%, with an AUC of 0.82 for primary PCa detection. Neither assessments with a single parameter (AUC, 0.54–0.79), nor different combinations with up to five parameters (AUC, 0.67–0.79) achieved equally good results. MP [¹¹C]Acetate PET-MRI improved local staging with a sensitivity, specificity, and diagnostic accuracy of 100%, 96%, and 97% compared to MRI alone with 72.2%, 100%, and 95.5%. MP [¹¹C]Acetate PET-MRI correctly detected osseous and liver metastases in five patients.

Conclusions

MP [¹¹C]Acetate PET-MRI merges morphologic with functional information, and allows insights into tumor biology. MP [¹¹C]Acetate PET-MRI with two MRI-derived parameters (T2 and DWI) yields the highest diagnostic accuracy. The addition of more parameters does not improve diagnostic accuracy of primary PCa detection. MP [¹¹C]Acetate PET-MRI facilitates improved local and distant staging, providing “one-stop” staging in patients with primary PCa, and therefore has the potential to improve therapy.

Patient summary

In this report we investigated MP [¹¹C]Acetate PET-MRI for detection, local and distant staging of prostate cancer. We demonstrate that MP [¹¹C]Acetate PET-MRI with two MRI-derived parameters (T2 and DWI) achieves the best diagnostic accuracy for primary prostate cancer detection and that MP [¹¹C]Acetate PET-MRI enables an improved local and distant staging.

Comprehensive molecular profiling of multi-focal prostate cancer and concomitant lymph node metastasis: Implications for tissue-based prognostic biomarkers

5061

Background: Current tissue-based prognostic biomarker assays claim that assessment of a single biopsy focus is sufficient to predict disease behavior. We analyzed and compared the genetic profiles of multifocal prostate cancer (PCa) with concordant lymph node metastasis (LNM) to determine if expression-based prognostic tests are robust to multifocality. Methods: This IRB-approved study comprised patients who underwent radical prostatectomy and lymph node dissection that revealed N1 or discordant multifocal (low- and high-grade foci) disease. DNA and RNA were co-isolated from each tumor focus pre-identified on formalin fixed paraffin embedded specimens. High depth, targeted DNA and RNA next generation sequencing was performed to characterize the molecular profile of each sample, using the Oncomine Comprehensive (11 patients) or Comprehensive Cancer (DNA, 3 patients) Panels and a custom targeted RNAseq panel comprising genes for deriving prognostic signatures. Results: A total of 67 primary tumor and 17 LNM foci from 14 patients were analyzed. We observed significant intra- and inter-patient molecular heterogeneity. For example, in patient #1, while all 4 regions of high-grade primary tumor showed TP53 somatic mutations and some copy number alterations (CNAs) with two samples from the LNM, tumor areas near the positive margin showed more complete concordance than intraprostatic regions. Critically, a low-grade primary tumor focus in this case showed no somatic mutation or CNA overlap with the high-grade or LNM samples. In patient #4, all tumor and LNM foci shared a large number of somatic mutations, including a frameshift mutation in PTEN, with no high level CNA, consistent with a hypermutated genotype. By targeted RNAseq, low- and high-grade tumors from the same patient showed distinct expression profiles using genes included in prognostic signatures. Conclusions: Our results challenge the claim that expression-based prognostic tests are robust to multifocality. Further studies are needed to better characterize the biologically dominant lesion in multifocal PCa and hold promise for the development of improved prognostic biomarkers.

Role of survivin expression in predicting biochemical recurrence after radical prostatectomy: a multi-institutional study

OBJECTIVE

To assess the association of survivin expression with clinicopathological features and biochemical recurrence (BCR) after radical prostatectomy (RP) in a large multi-institutional cohort.

METHODS

Survivin expression was evaluated by immunohistochemistry on a tissue microarray of RP cores from 3 117 patients. Survivin expression was considered altered when at least 10% of the tumour cells stained positive. The association of altered survivin expression with BCR was evaluated using Cox proportional hazards regression models.

RESULTS

Survivin expression was altered in 1 330 patients (42.6%). Altered expression was associated with higher Gleason score on RP (P = 0.001), extracapsular extension (P = 0.019), seminal vesicle invasion (P < 0.001) and lymph node metastases (P = 0.009). The median (interquartile range) follow-up was 38 (21-66) months. Patients with altered survivin expression had a shorter BCR-free survival time than those with normal expression (5-year BCR-free survival estimates: 74.7 vs 79.0%; P = 0.008). Altered survivin expression did not retain its prognostic value, however, after adjustment for the effect of established clinicopathological factors (P = 0.73). Subgroup analyses also showed no independent prognostic value of survivin.

CONCLUSIONS

Survivin expression is commonly altered in patients undergoing RP. Altered survivin expression is associated with the clinicopathological features of biologically and clinically aggressive PCa. Survivin expression was associated with BCR only in univariable analysis, limiting its value in daily clinical decision-making.

IL-6/STAT3/ARF: the guardians of senescence, cancer progression and metastasis in prostate cancer

Prostate cancer is one of the most prevalent forms of cancer in men worldwide. It remains a clinical challenge to identify lethal metastatic prostate cancers, which escape standard therapeutic intervention. Aberrant interleukin-6 (IL-6) / signal transducer and activator of transcription-3 (STAT3) signalling and loss of p53 occur during prostate cancer progression to metastatic disease. The abnormality of the IL-6/STAT3/p53 axis is frequently accompanied by other genetic alterations; however, its potential role as an important mediator of oncogenic reprogramming, invasion and metastatic transformation remains unknown. The failure of anti-IL-6 treatments is still unexplained and may be due to an incomplete understanding of the mechanism of the in vivo role of IL-6/STAT3 in prostate cancer. The identification of the alternative reading frame protein (ARF) / murine double minute protein (MDM2) / p53 tumour suppressor pathway potentially involving the IL-6/STAT3 axis as a restricting factor in prostate cancer deficient in the tumour suppressor phosphatase and tensin homologue (PTEN) opened new avenues to currently available therapies. This review summarises the current knowledge on the role of crucial pathways driving prostate cancer progression as well as metastatic disease and discusses the potential use of novel specific target molecules and how it can be exploited to avoid overtreatment and increase quality of life.

Prognostic value of Caveolin-1 in patients treated with radical prostatectomy: a multicentric validation study

OBJECTIVE

To validate Caveolin-1 as an independent prognostic marker of biochemical recurrence (BCR) in a large multi-institutional cohort of patients with prostate cancer treated with radical prostatectomy (RP).

PATIENTS AND METHODS

Caveolin-1 expression was evaluated by immunochemistry on a tissue microarray in 3 117 patients treated with RP for prostate cancer at five institutions. Univariable and multivariable Cox proportional hazards regression models assessed the association of Caveolin-1 status with BCR. Harrell's c-index quantified prognostic accuracy.

RESULTS

Caveolin-1 was overexpressed in 644 (20.6%) patients and was associated with higher pathological Gleason sum (P = 0.002) and lymph node metastases (P = 0.05). Within a median (interquartile range) follow-up of 38 (21-66) months, 617 (19.8%) patients experienced BCR. Patients with overexpression of Caveolin-1 had worse BCR-free survival than those with normal expression (log-rank test, P = 0.004). Caveolin-1 was an independent predictor of BCR in multivariable analyses that adjusted for the effects of standard clinicopathological features (hazard ratio 1.21, P = 0.037). Addition of Caveolin-1 in a model for prediction of BCR based on these standard prognosticators did not significantly improve the predictive accuracy of the model. In subgroup analyses, Caveolin-1 was associated with BCR in patients with favourable pathological features (pT2pN0 and Gleason score = 6; P = 0.021).

CONCLUSIONS

We confirmed that overexpression of Caveolin-1 is associated with adverse pathological features in prostate cancer and independently predicts BCR after RP, especially in patients with favourable pathological features. However, it did not add prognostically relevant information to established predictors of BCR, limiting its use in clinical practice.

STAT3 regulated ARF expression suppresses prostate cancer metastasis

Prostate cancer (PCa) is the most prevalent cancer in men. Hyperactive STAT3 is thought to be oncogenic in PCa. However, targeting of the IL-6/STAT3 axis in PCa patients has failed to provide therapeutic benefit. Here we show that genetic inactivation of Stat3 or IL-6 signalling in a Pten-deficient PCa mouse model accelerates cancer progression leading to metastasis. Mechanistically, we identify p19^ARF as a direct Stat3 target. Loss of Stat3 signalling disrupts the ARF–Mdm2–p53 tumour suppressor axis bypassing senescence. Strikingly, we also identify STAT3 and CDKN2A mutations in primary human PCa. STAT3 and CDKN2A deletions co-occurred with high frequency in PCa metastases. In accordance, loss of STAT3 and p14^ARF expression in patient tumours correlates with increased risk of disease recurrence and metastatic PCa. Thus, STAT3 and ARF may be prognostic markers to stratify high from low risk PCa patients. Our findings challenge the current discussion on therapeutic benefit or risk of IL-6/STAT3 inhibition.

IL6-STAT3 signaling is activated in prostate cancer, however inhibiting this pathway has not lead to a survival advantage in patients. Here, Pencik et al. show that loss of the IL6-STAT3 axis in mice and humans leads to metastasis due to loss of ARF, unravelling STAT3 and ARF as potential prognostic markers in prostate cancer.

ERCC1 as a Prognostic and Predictive Biomarker for Urothelial Carcinoma of the Bladder following Radical Cystectomy

PURPOSE

ERCC1 is the key enzyme of the nucleotide excision repair pathway, which maintains genomic stability. ERCC1 has been proposed as a prognostic and predictive biomarker for patients with urothelial carcinoma of the bladder but there are limited data on patients after radical cystectomy.

MATERIALS AND METHODS

ERCC1 was evaluated by immunohistochemistry in radical cystectomy specimens of 432 patients. Associations with disease-free and cancer specific survival, and the effect of adjuvant cisplatin based chemotherapy were assessed. Further, ERCC1 mRNA expression and in vitro sensitivity to cisplatin were correlated in 25 bladder urothelial carcinoma cell lines.

RESULTS

ERCC1 was expressed in 308 tumors (71.3%). There was no association with clinicopathological variables (each p >0.3). Median postoperative followup was 128 months. On multivariable analyses patients with ERCC1 positive tumors had significantly better disease-free survival (HR 0.70, p = 0.028) and cancer specific survival (HR 0.70, p = 0.032) than those with ERCC1 negative tumors. Discrimination of the multivariable models increased by 0.7% to 0.9% following the inclusion of ERCC1. There was no modification of the effect of adjuvant cisplatin based combination chemotherapy by ERCC1 status (p = 0.38 and 0.88, respectively). There was also no correlation between ERCC1 and sensitivity to cisplatin in vitro (R(2) = 0.02, p = 0.46).

CONCLUSIONS

ERCC1 may be a prognostic biomarker for urothelial carcinoma of the bladder. Patients with ERCC1 positive tumors may have better survival than those with ERCC1 negative tumors. However, the efficacy of adjuvant cisplatin based chemotherapy appears to be unrelated to ERCC1 status.

Carbonic anhydrase IX as a diagnostic urinary marker for urothelial bladder cancer

Urinary biomarkers are needed to improve the management and reduce the cost of urothelial bladder cancer (UBC); however, none have been recommended yet for clinical practice. This study evaluated carbonic anhydrase IX (CAIX) as a diagnostic urinary biomarker for UBC. CAIX was analyzed by quantitative polymerase chain reaction in urine samples of 196 patients with UBC and 123 controls with hematuria. Paired samples from urine and tumor tissue were evaluated in 16 cases. Data were validated in 155 independent samples. The sensitivity and specificity of CAIX for UBC detection were 86.2% and 95.1%, respectively (area under the curve [AUC]: 90.5%). There was a significant association of CAIX expression between the paired urine and tumor specimens (p=0.002). CAIX showed a significantly higher predictive accuracy than urinary cytology (90.5% vs 71.7%), specifically in low-grade tumors (90.0% vs 61.8%). CAIX expression decreased with increasing tumor stage and grade. Analyses in an independent validation cohort confirmed the high accuracy of CAIX for diagnosing UBC (AUC: 88.3%).

PATIENT SUMMARY

We evaluated carbonic anhydrase IX (CAIX) as a urinary marker for bladder cancer (BCa) using a large series of patients from a single hospital. We found that urinary CAIX has a high sensitivity and specificity for diagnosing BCa.

Abstract 3138: IL-6/Stat3 signaling is an indispensable modulator of oncogene-induced cellular senescence

IL-6/Stat3 signaling plays a role as a proto-oncogene in various tumors including prostate cancer, where IL-6 has been explored as therapeutic target. Deficiency of Pten, one of the most commonly mutated genes in cancer, directly triggers a senescence program critically depending on the p19Arf-p53 fail-safe pathway. We identified a novel and unexpected tumor suppressive role of IL-6/Stat3 signaling in a Pten-deficient murine prostate cancer model. Our data provide evidence that activation of IL-6/Stat3 signaling axis is implicated in oncogene-induced senescence (OIS). Strikingly, genetic ablation of IL-6 strongly promoted prostate cancer initiation, progression and metastasis in Pten-deficient mice. Mechanistically, IL6/Stat3 signaling regulates p19Arf-p53-induced senescence by modulating expression of the ubiquitin ligase MDM2 in pre-neoplastic cells. Critically, in prostate cancer patients low expression of Stat3 or p14Arf, the human homologue of p19Arf, correlates with poor survival. Therefore, the IL-6/Stat3 signaling axis may represent a novel molecular target for senescence-based cancer therapies.

Citation Format: Jan Pencik, Michaela Schlederer, Melanie Hassler, Wolfgang Gruber, Fritz Aberger, Richard Kennedy, Stephen Walker, Stephan Rose-John, Valeria Poli, Robert Eferl, Harald Esterbauer, Osman Aksoy, Merima Herac, Peter Mazal, Andrea Haitel, Martin Susani, Richard Moriggl, Zoran Culig, Lukas Kenner. IL-6/Stat3 signaling is an indispensable modulator of oncogene-induced cellular senescence. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 3138. doi:10.1158/1538-7445.AM2014-3138

Quantitative apparent diffusion coefficient measurements obtained by 3-Tesla MRI are correlated with biomarkers of bladder cancer proliferative activity

Purpose

To investigate the association between Apparent Diffusion Coefficient (ADC) values and cell cycle and proliferative biomarkers (p53, p21, Ki67,) in order to establish its potential role as a noninvasive biomarker for prediction of cell cycle, proliferative activity and biological aggressiveness in bladder cancer.

Materials and Methods

Patients with bladder cancer who underwent 3,0 Tesla DW-MRI of the bladder before TUR-B or radical cystectomy were eligible for this prospective IRB-approved study. Histological specimen were immunohistochemically stained for the following markers: p53, p21 and ki67. Two board-certified uropathologists reviewed the specimens blinded to DW-MRI results. Histological grade and T-stage were classified according to the WHO 2004 and the 2009 TNM classification, respectively. Nonparametric univariate and multivariate statistics including correlation, logistic regression and ROC analysis were applied.

Results

Muscle invasive bladder cancer was histologically confirmed in 10 out of 41 patients. All examined tissue biomarkers were significantly correlated with ADC values (p<0.05, respectively). Based on multivariate analysis, p53 and ADC are both independent prognostic factors for muscle invasiveness of bladder cancer (>/ = T2). (p = 0.013 and p = 0.018).

Conclusion

ADC values are associated with cell cycle and proliferative biomarkers and do thereby reflect invasive and proliferative potential in bladder cancer. ADC and p53 are both independent prognostic factors for muscle invasiveness in bladder cancer.

P16INK4A immunohistochemistry for detection of human papilloma virus-associated penile squamous cell carcinoma is superior to in-situ hybridization

We evaluated p16INK4A as a reliable option to detect human papilloma virus (HPV) DNA in penile tumor specimens. Formalin-fixed paraffin embedded samples of 26 patients with penile cancer and another 18 cases with non-tumorigenic lesions were stained by three different widely used commercially available chromogenic in-situ hybridization assays high-risk HPV CISH Y1443 (Genpoint, DAKO), pan HPV CISH Y1404 (Genpoint, DAKO), INFORM HPV III (Ventana, Tucson, Arizona) and p16INK4A immunohistochemistry, then compared to the known gold standard polymerase chain reaction detecting HPV 16, 18, 31, and 33. Immunoreactivity for p16INK4A was evaluated by using a 4-tiered (0, 1, 2, and 3) pattern based system. 19 cases were positive for p16INK4A, 13 of which showed a continuous transepithelial staining (pattern 3). Pan HPV ISH showed positivity in 9 cases, high-risk HPV ISH in 7 cases and INFORM HPVIII ISH in 7 cases. p16INK4A IHC pattern 3 versus pattern 0, 1 and 2 exhibited a specificity and positive predictive value of 100 percent, with a sensitivity and negative predictive value of 72 and 62 percent, respectively, which was much better than all HPV in-situ hybridization methods referred to polymerase chain reaction. p16INK4A seems to be a superior marker for the detection of HPV-associated penile squamous cell carcinoma compared to CISH tests, but is not recommend for the detection of non-tumorigenic lesions, where PCR should be used for the initial assessment.

Immunohistochemical expression of PDGFR, VEGF-C, and proteins of the mToR pathway before and after androgen deprivation therapy in prostate carcinoma: significant decrease after treatment

Targeted therapy in hormone refractory prostate cancer (HRPC) is currently under evaluation in many trials. The effect of androgen deprivation therapy (ADT) on many targets in prostate cancer is incompletely known. For the first time, immunohistochemical expression of the platelet-derived growth factor receptor (PDGFR), epidermal growth factor receptor (EGFR), vascular endothelial growth factor C (VEGF-C), mammalian target of rapamycin (mToR), p70 ribosomal protein S6 kinase 1 (PS6K), human epidermal growth factor receptor 2 (c-erbB-2), and carbonic anhydrase IX (CA9) was evaluated in 44 patients with prostate carcinoma treated with or without ADT, at biopsy time and after radical prostatectomy. PDGFR, VEGF-C, mToR, and PS6K expression was significantly reduced (p = 0.002, p = 0.035, p = 0.025, and p = 0.033, respectively) after ADT, whereas expression of EGFR, c-erbB-2, and CA9 was not influenced by ADT. In conclusion, targeting PDGFR, VEGF-C, mToR, or PS6K after ADT should be considered with precaution, as those targets can severely be altered or functionally deregulated by ADT.

[Osteosarcoma of the prostate after radiotherapy]

Osteosarcoma of the prostate is a rare finding. These tumours usually occur years after radiotherapy for prostate cancer. We report the case of a 74-year-old man with prostate cancer who had been treated with radiotherapy and androgen deprivation therapy. The man presented with urinary retention and his prostate was transurethrally resected. The histopathological investigation showed formations of a poorly differentiated osteosarcoma in the prostate. Because of serious comorbidities we decided to withhold chemotherapy considering its potential side effects. The man died a few months after the diagnosis of osteosarcoma in the prostate with the disease in a metastatic stage. In conclusion, osteosarcoma of the prostate is a rarely reported consequence of radiotherapy in patients with prostate cancer and is characterised by poor life expectancy.

Renal cell carcinoma associated with transcription factor E3 expression and Xp11.2 translocation: incidence, characteristics, and prognosis

We studied the characteristics and prognosis of renal cell carcinoma (RCC) associated with Xp11.2 translocation and transcription factor E3 (TFE3) expression and determined the need for genetic analysis in routine diagnostics. Of 848 consecutive cases, 75 showed microscopic features suggestive of Xp11.2 translocation RCC or occurred in patients 40 years or younger. Of these cases, 17 (23%) showed strong nuclear TFE3 immunostaining, which was associated with more advanced tumors and inverse prognosis in univariate (P = .032) but not multivariate (P = .404) analysis. With fluorescence in situ hybridization and polymerase chain reaction, only 2 cases showed alterations of the X chromosome and the ASPL-TFE3 gene fusion, respectively. In our laboratory, the predictive value of TFE3 expression for the Xp11.2 translocation was 12%. Strong nuclear TFE3 expression is associated with metastatic spread and a poor prognosis. In our laboratory, TFE3 is not diagnostic for Xp11.2 translocation RCC. Diagnosis of Xp11.2 translocation RCC may be made only genetically.

Quantification of extraprostatic perineural spread and its prognostic value in pT3a pN0 M0 R0 prostate cancer patients

BACKGROUND

The prognostic relevance of the amount of extraprostatic cancer spread in nerves in prostate cancer patients is not well established.

METHODS

Eighty-eight patients were included in our study with pT3a pN0 M0 R0 prostate cancer treated with retropubic prostatectomy. Eighty-seven of them showed perineural invasion, 54 were confined to the prostate, 33 showed cancer spread in extraprostatic nerves, which was quantified by counting each transverse section of nerves infiltrated by cancer in totally embedded specimens. Biochemical relapse was established by serum PSA levels of ≥0.2 ng/ml as well as PSA ≥ 0.4 ng/ml and higher according to the EAU guidelines.

RESULTS

Extraprostatic but not intraprostatic perineural infiltration was significantly more often found in tumors of higher Gleason score. Intraprostatic number of infiltrated nerves (NIN) correlated with extraprostatic NIN. There was no association between extraprostatic or intraprostatic NIN and Gleason score, lymphatic, or blood vessel invasion. Extraprostatic neural infiltration in ≤10 nerves extended relapse free survival in univariate analysis for PSA 0.2 and 0.4 ng/ml (P = 0.002 and P < 0.000001, respectively) and remained significant in multivariate analysis for PSA 0.4 ng/ml (P = 0.039).

CONCLUSIONS

High amount of extraprostatic NIN correlates with tumor progression and seems to be an independent prognostic parameter.

The human female prostate-immunohistochemical study with prostate-specific antigen, prostate-specific alkaline phosphatase, and androgen receptor and 3-D remodeling

INTRODUCTION

The constitution of glands surrounding the human female urethra has been under debate; especially regarding as to what extent they equal the male prostate. Defining their composition may help to understand the development of neoplasms arising from this tissue.

AIMS

The aim of this study was to define the existence, structure, and arrangement of a possible human female prostate.

METHODS

Urethras of 25 women were investigated by immunohistochemistry and stained with specific monoclonal antibodies against prostate-specific antigen (PSA, mono- and polyclonal antibody), prostate specific alkaline phosphatase (PSAP), and androgen receptor (AR). From two urethras, which underwent a totally serial work up with PSA-staining, a three-dimensional model of the urethra and the prostatic glands was created to enable 3D-perception of the results.

MAIN OUTCOME MEASURE

The main outcome measures used in this study were identifying glandular structures in hematoxylin-eosin-staining, positive staining with the respective antibodies, and 3-D orientation of described glands.

RESULTS

Fourteen of 25 patients had glandular structures encircling the urethra. Twelve of 14 showed positive staining for PSA, PSAP, and AR in gland acini, while the excretory ducts, the urethra, and the surrounding stroma did not express those proteins. The strongest PSA and PSAP expression was found in apical cytoplasm of the glandular cells, and AR was confined to cell nuclei. Prostatic glands were located laterally to the distal half of the urethra.

CONCLUSION

A female prostate was found in every second woman in this study and can be discriminated from other urethral caverns and immature paraurethral ducts. Possible neoplasms of this source tissue expressing the prostate-specific markers may therefore be denominated as female prostate tumors.