Standard of Care Versus Metastases-directed Therapy for PET-detected Nodal Oligorecurrent Prostate Cancer Following Multimodality Treatment: A Multi-institutional Case-control Study

BACKGROUND

Most prostate cancer (PCa) patients with a biochemical failure following primary multimodality treatment (surgery and postoperative radiotherapy) relapse in the nodes.

OBJECTIVE

To perform a matched-case analysis in men with lymph node recurrent PCa comparing standard of care (SOC) with metastasis-directed therapy (MDT).

DESIGN, SETTING, AND PARTICIPANTS

PCa patients with a prostate-specific antigen (PSA) progression following multimodality treatment were included in this retrospective multi-institutional analysis.

INTERVENTION

The SOC cohort (n=1816) received immediate or delayed androgen deprivation therapy administered at PSA progression. The MDT cohort (n=263) received either salvage lymph node dissection (n=166) or stereotactic body radiotherapy (n=97) at PSA progression to a positron emission tomography-detected nodal recurrence.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

The primary endpoint, cancer-specific survival (CSS), was analyzed using the Kaplan-Meier method, log-rank test, Cox proportional hazards models, and propensity score-matched analyses.

RESULTS AND LIMITATIONS

At a median follow-up of 70 (interquartile range: 48-98) mo, MDT was associated with an improved CSS on univariate (p=0.029) and multivariate analysis (hazard ratio: 0.33, 95% confidence interval [CI]: 0.17-0.64) adjusted for the year of radical prostatectomy (RP), age at RP, PSA at RP, time from RP to PSA progression, Gleason score, surgical margin status, pT- and pN-stage. In total, 659 men were matched (3:1 ratio). The 5-yr CSS was 98.6% (95% CI: 94.3-99.6) and 95.7% (95% CI: 93.2-97.3) for MDT and SOC, respectively (p=0.005, log-rank). The main limitations of our study are its retrospective design and lack of standardization of systemic treatment in the SOC cohort.

CONCLUSIONS

MDT for nodal oligorecurrent PCa improves CSS as compared with SOC. These retrospective data from a multi-institutional pooled analysis should be considered as hypothesis-generating and inform future randomized trials in this setting.

PATIENT SUMMARY

Prostate cancer patients experiencing a lymph node recurrence might benefit from local treatments directed at these lymph nodes.

High BCAR1 expression is associated with early PSA recurrence in ERG negative prostate cancer

BACKGROUND

Breast cancer anti-estrogen resistance 1 (BCAR1/p130cas) is a hub for diverse oncogenic signaling cascades and promotes tumor development and progression.

METHODS

To understand the effect of BCAR1 in prostate cancer, we analyzed its expression on more than 11,000 prostate cancer samples. BCAR1 expression levels were compared with clinical characteristics, PSA recurrence, molecular subtype defined by ERG status and 3p, 5q, 6q and PTEN deletion.

RESULTS

BCAR1 staining was barely detectable in normal prostate glands but seen in 77.6% of 9472 interpretable cancers, including strong expression in 38.5%, moderate in 23.2% and weak in 15.9% of cases. BCAR1 up regulation was associated with positive ERG status (p < 0.0001), high Gleason score (p < 0.0001), advanced pathological tumor stage (p = 0.0082), lower preoperative PSA level (p < 0.0001), increased cell proliferation (p < 0.0001), early PSA recurrence (p = 0.0008), and predicted prognosis independently from clinico-pathological parameters available at the time of the initial biopsy. However, subset analyses revealed that the prognostic impact of BCAR1 expression was limited to ERG-negative cancer. That BCAR1 up regulation was linked to almost all analyzed deletions (p < 0.0001 each for PTEN, 5q, 6q deletion) may suggest a functional link to genomic instability.

CONCLUSION

The results of our study identify BCAR1 as a prognostic biomarker with potential clinical value for risk stratification of ERG-negative prostate cancer.

FOXA1 expression is a strong independent predictor of early PSA recurrence in ERG negative prostate cancers treated by radical prostatectomy

FOXA1 (Fork-head box protein A1, HNF-3a) is a transcription factor involved in androgen signaling with relevance for lineage-specific gene expression of the prostate. The expression was analyzed by immunohistochemistry on a tissue microarray containing 11152 prostate cancer specimens. Results were compared with tumor phenotype, biochemical recurrence, androgen receptor expression, ETS-related gene (ERG) status and other recurrent genomic alterations. FOXA1 expression was detectable in 97.6% of 8227 interpretable cancers and considered strong in 28.5%, moderate in 46.2% and weak in 22.9% of cases. High FOXA1 expression was associated with TMPRSS2:ERG rearrangement and ERG expression (P < 0.0001). High FOXA1 expression was linked to high Gleason grade, advanced pathological tumor (pT) stage and early PSA recurrence in ERG negative cancers (P < 0.0001), while these associations were either weak or absent in ERG positive cancers. In ERG negative cancers, the prognostic role of FOXA1 expression was independent of Gleason grade, pathological tumor stage, lymph node stage, surgical margin status and preoperative PSA. Independent prognostic value became even more evident if the analysis was limited to preoperatively available features such as biopsy Gleason grade, preoperative PSA, cT stage and FOXA1 expression (P < 0.0001). Within ERG negative cancers, FOXA1 expression was also strongly associated with PTEN and 5q21 deletions (P < 0.0001). High expression of FOXA1 is an independent prognostic parameter in ERG negative prostate cancer. Thus, FOXA1 measurement might provide clinically useful information in prostate cancer.

Comparison of 11 Active Surveillance Protocols in Contemporary European Men Treated With Radical Prostatectomy

BACKGROUND

The aim of this study was to compare 11 active surveillance (AS) protocols in contemporary European men treated with radical prostatectomy (RP) at the Martini-Clinic Prostate Cancer Center.

PATIENTS AND METHODS

Analyzed were 3498 RP patients, from 2005 to 2016, who underwent ≥ 10 core biopsies and fulfilled at least 1 of 11 examined AS entry definitions. We tested proportions of AS eligibility, ineligibility, presence of primary Gleason 4/5, upstage, and combinations thereof at RP, as well as 5-year biochemical recurrence-free survival (BFS).

RESULTS

The most and least stringent criteria were very low risk National Comprehensive Cancer Network and Royal Marsden with 18.8% and 96.1% of AS-eligible patients, respectively. Rates of primary Gleason 4/5 at RP, upstaging, or both features, respectively, ranged from 2.3% to 6.7%, 6.1% to 18.2%, and 7.1% to 21.0% for those 2 AS entry definitions. The range of individuals deemed AS-ineligible between the same 2 AS entry definitions, despite not harboring unfavorable pathology (primary Gleason pattern 4/5, upstage, or both), was 80.3% to 3.7%, 78.3% to 3.4%, and 77.8% to 3.4%, respectively. BFS rates showed narrow variability, with a range of 85.9% to 91.8%.

CONCLUSION

Use of stringent AS entry definitions reduces the number of AS-eligible patients, which is related to a select range in individual entry parameters. Moreover, rates of unfavorable pathology at RP as much as tripled between most and least stringent AS entry definitions. However, less stringent AS entry definitions result in the lowest AS-ineligibility rates, in men without unfavorable pathology. BFS rates were virtually invariably high. Clinicians should know differences in key parameters underlying each AS entry definition, associated effect on rates of eligibility, and potential misclassification of individuals.

Does Cytoreductive Prostatectomy Really Have an Impact on Prognosis in Prostate Cancer Patients with Low-volume Bone Metastasis? Results from a Prospective Case-Control Study

The impact of cytoreductive radical prostatectomy (CRP) on oncological outcomes in patients with prostate cancer (PCa) and distant metastases has been demonstrated by retrospective data with their potential selection bias. Using prospective institutional data, we compared the outcomes between 43 PCa patients with low-volume bone metastases (1-3 lesions) undergoing CRP (median follow-up 32.7 mo) and 40 patients receiving best systemic therapy (BST; median follow-up 82.2 mo). The inclusion criteria for both cohorts were identical. So far, no significant difference in castration resistant-free survival (p=0.92) or overall survival (p=0.25) has been detected. Compared to recent reports, the outcomes for our control group are more favorable, indicating a potential selection bias in the previous retrospective studies. Therefore, the unclear oncological effect has to be weighed against the potential risks of CRP. However, patients benefit from a significant reduction in locoregional complications (7.0% vs 35%; p<0.01) when undergoing CRP.

PATIENT SUMMARY

In this study we analyzed the impact of surgery in patients with prostate cancer and bone metastases. Using prospective data, we could not show a significant benefit of surgery on survival, but the rate of locoregional complications was lower. Therefore, patients should be treated within prospective trials evaluating the role of cytoreductive prostatectomy in low-volume, bone metastatic prostate cancer.

Validation of cAMP phosphodiesterase-4D7 (PDE4D7) for its independent contribution to risk stratification in a prostate cancer patient cohort with longitudinal biological outcomes

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Background: In this study we present the retrospective validation of the prognostic prostate cancer biomarker PDE4D7 in predicting longitudinal biological outcomes in a historical cohort of radical prostatectomy patients. Methods: Biopsy punches from 550 patients were collected from a representative tumor area of FFPE surgical resections. RNA was extracted and PDE4D7 quantified by one-step RT-qPCR. PDE4D7 scores were calculated by normalization of PDE4D7 to the averaged expression of four reference genes. The independent prognostic value of the PDE4D7 scores were evaluated using uni- and multivariate Cox proportional hazard regression. Multivariate analyses were adjusted for clinical prognostic variables. Post-surgical outcomes tested were: PSA relapse, start of salvage treatment, progression to metastases, overall and prostate cancer specific mortality. Logistic regression was used to create a combined prognostic model of PDE4D7 with clinical risk and tested in outcome prediction. Results: The PDE4D7 score was significantly associated with time to PSA failure after prostatectomy (HR 0.53; 95% CI 0.41-0.67 for each unit increase; p < 1.0E-04). After adjustment for pathology Gleason, pT stage, surgical margin status, and seminal vesicle invasion the HR was 0.55 (95% CI 0.43-0.72; p < 1.0E-04). Patients with a high PDE4D7 score that were clinically classified as intermediate to high risk of progression were re-classified into a group with an average progression risk less than the average cohort risk of clinically very low risk patients. The maximum benefit, compared to Gleason score, was observed in the clinically intermediate favorable risk group. Combining clinical risk with PDE4D7 scores improved the overall risk stratification. Conclusions: The PDE4D7 score has potential to provide independent risk information and, in particular, to re-stratify patients with clinical intermediate to high risk characteristics to a very low risk profile.

[DGFIT: Immune and Targeted Therapy at ASCO 2016 - What will the Future Bring?]

Die Renaissance der spezifischen Immuntherapie eröffnet neue mannigfaltige Behandlungsoptionen in der Uroonkologie. Die Deutsche Gesellschaft für Immun- und Targeted Therapie (DGFIT) gibt einen Überblick über den aktuellen Stand und die neuen wissenschaftlichen Entwicklungen der Immun- und Targeted Therapie, welche dieses Jahr auf den Fachtagungen präsentiert wurden. Neben dem Nierenzellkarzinom, bei welchem bereits ein Immuncheckpoint-Inhibitor zur Therapie des metastasierten Stadiums zugelassen ist, werden beim Blasen- und Prostatakarzinom sowohl die für den Kliniker relevanten Ergebnisse als auch die neuesten, möglicherweise zukünftig relevanten Entwicklungen zusammengefasst.

Heterogeneity and chronology of 6q15 deletion and ERG-fusion in prostate cancer

Prostate cancer is notorious for its heterogeneity, which poses a problem for the applicability of diagnostic molecular markers. However, heterogeneity analysis can provide valuable information on the chronology in which molecular alterations arise. Here, we constructed a heterogeneity tissue microarray (TMA) comprising samples from 10 different tumor areas of 189 prostate cancers each in order to study the sequence of two frequent molecular alterations, i.e. 6q15 deletion and TMPRSS2:ERG fusion. Previous work shows a marked inverse relationship between these alterations, suggesting that presence of one of these alterations might impact development of the other. 6q15 deletion was analyzed by fluorescence in situ hybridization and ERG-expression by immunohistochemistry. Only 6.6% of 334 ERG-positive but 28.4% of 440 ERG-negative TMA spots showed 6q15 deletions (p < 0.0001). A breakdown of these data to the level of tumor foci revealed 6q deletions in 138 tumor foci that were large enough to have at least 3 analyzable TMA spots. These included 42 tumor foci with homogeneous ERG positivity and 16 with homogeneous 6q15 deletions. Remarkably, six of the 42 homogeneously ERG-positive tumor foci (14.3%) harbored small 6q15-deleted areas, but none of the 34 6q15-deleted foci showed areas of ERG positivity (p = 0.022). In conclusion, our data suggest that ERG-fusion can precede 6q15 deletion, but not vice versa. The complete absence of ERG-positive tumor areas in 6q15-deleted tumor foci further suggest that the functional consequences of 6q15 deletions may prevent the development of TMPRSS2:ERG fusions.

Genomic deletion of chromosome 12p is an independent prognostic marker in prostate cancer

Deletion of 12p is a recurrent alteration in prostate cancer, but the prevalence and clinical consequences of this alteration have not been studied in detail. Dual labeling fluorescence in situ hybridization using probes for 12p13 (CDKN1B; p27) and centromere 12 as a reference was used to successfully analyze more than 3700 prostate cancers with clinical follow-up data assembled in a tissue microarray format. CDKN1B was selected as a probe because it is located in the center of the deletion, which spans > 10 Mb and includes > 50 genes in 80% of cancers with 12p deletion. Deletion of 12p was found in 13.7% of cancers and included 13.5% heterozygous and 0.2% homozygous deletions. 12p deletion were linked to advanced tumor stage (p < 0.0001), high Gleason grade (p < 0.0001), rapid tumor cell proliferation (p < 0.0001), lymph node metastasis (p = 0.0004), and biochemical recurrence (p = 0.0027). Multivariate analysis including pT stage (p < 0.0001), Gleason grade (p < 0.0001), pN status (p = 0.0001), preoperative PSA levels (p = 0.0001), and resection margin status (p = 0.0001) revealed an independent prognostic value of 12p deletion (p = 0.0014). Deletion of 12p was unrelated to the ERG fusion status. Deletion of 12p was only marginally linked to reduced p27 expression, which by itself was unrelated to clinical outcome. This argues against p27 as the key target gene of 12p deletions. In summary, the results of our study demonstrate that 12p deletion is frequent in prostate cancer and provides independent prognostic information. 12p deletion analysis alone, or in combination with other prognostic parameters may thus have clinical utility.

The Impact of Repeat Prostate Biopsies on Oncologic, Pathological and Perioperative Outcomes after Radical Prostatectomy

PURPOSE

The impact of repeat biopsy sessions on radical prostatectomy remains controversial regarding perioperative, pathological and oncologic outcome.

MATERIALS AND METHODS

We analyzed the records of 12,624 patients who underwent radical prostatectomy from 2007 to 2013. The association of the number of biopsy sessions (range 1 to 3 or more) with pathological outcomes and perioperative complications was analyzed using the Wilcoxon matched pair test. To test the association between biopsy sessions and biochemical recurrence-free survival we used Kaplan-Meier curves and multivariable Cox regression analysis.

RESULTS

Of the patients 89.2% had 1 biopsy session, 7.4% had 2 sessions and 3.4% had 3 or more sessions. Median followup was 36.6 months. In patients with 1, 2 and 3 or more biopsy sessions prostate volume (38, 44 and 45 ml) and prostate specific antigen (6.7, 7.6 and 10.1 ng/ml, respectively) were greater (each p <0.001). The perioperative outcome was more favorable. Patients with 1, 2 and 3 or more biopsy sessions more often had organ confined tumors (67.6%, 72.1% and 72.9%, p = 0.003) and higher tumor volume (3.1, 3.0 and 3.6 ml, p <0.001) but a lower tumor percent (7.5%, 3.7% and 2.4%, respectively, p <0.001). More biopsy sessions were associated with fewer lymph node metastases (1, 2 and 3 sessions 0.23, 0.13 and 0.17, respectively, p <0.001). Gleason score and surgical margin status did not differ. The overall biochemical recurrence rate was 18.9% and it was comparable among the biopsy groups. No association was found between the number of biopsies and biochemical recurrence.

CONCLUSIONS

Patients with multiple biopsy sessions experience a slightly more favorable pathological outcome without an impact on the oncologic outcome. The perioperative outcome was more favorable in patients with multiple biopsies.

Primary Gleason pattern upgrading in contemporary patients with D'Amico low-risk prostate cancer: implications for future biomarkers and imaging modalities

OBJECTIVE

To retrospectively assess the rate of high-grade primary Gleason upgrading (HGPGU) to primary Gleason pattern 4 or 5 in a contemporary cohort of patients with D'Amico low-risk prostate cancer including those who fulfilled Prostate Cancer Research International Active Surveillance (PRIAS) criteria, and to develop a tool for HGPGU prediction. HGPGU is a contraindication in most active surveillance (AS) and focal therapy protocols.

PATIENTS AND METHODS

In all, 10 616 patients with localised prostate cancer were treated at a high-volume European tertiary care centre from 2010 to 2015 with radical prostatectomy. Analyses were restricted to 1 819 patients with D'Amico low-risk prostate cancer (17.1%) with prostate-specific antigen (PSA) levels of <10.0 ng/mL, cT1c-cT2a and Gleason score ≤6, and were repeated within 772 of the men (7.3%) who fulfilled the PRIAS criteria for AS (PSA level of ≤10 ng/mL, T1c-T2, Gleason score ≤6, PSA density (PSAD) of <0.2 ng/mL² , ≤2 positive cores). Uni- and multivariable logistic regression models were fitted, testing predictors of HGPGU. The final logistic regression model was based on the most informative variables.

RESULTS

There was HGPGU in 88 (4.8%) patients with D'Amico low-risk prostate cancer and in 32 (4.1%) of the subgroup who were PRIAS eligible. Multivariable analysis predicting HGPGU for the patients with D'Amico low-risk yielded three independent predictors: age, PSAD, and clinical tumour stage (P = 0.008, P = 0.005 and P = 0.021, respectively). Within the same patients, the model using all vs the most informative variables resulted in area under the curves (AUCs) of 69.2% and 68.3%, respectively. Multivariable analysis of those who were PRIAS eligible, yielded age and number of positive cores as independent predictors of HGPGU (P = 0.002 and P = 0.049, respectively; AUC 64.9%).

CONCLUSIONS

The low accuracy (invariably <70%) for HGPGU prediction in both patients with D'Amico low-risk prostate cancer and PRIAS eligibility indicates that these variables have poor predictive ability in contemporary patients. Despite HGPGU being a rare phenomenon, it may have life threatening implications and consequently alternatives such as biomarkers, genetic markers, or imaging modalities at re-biopsy are needed.

Overexpression of thymidylate synthase (TYMS) is associated with aggressive tumor features and early PSA recurrence in prostate cancer

Thymidylate synthase (TYMS) plays a role in DNA synthesis and is a target for 5-fluorouracil. In this study TYMS was analyzed by immunohistochemistry on a tissue microarray containing 11,152 prostate cancers. TYMS expression was higher in neoplastic than in normal prostate epithelium and was detectable in 72.9% of 10,223 interpretable cancers. It was considered strong in 21.9%, moderate in 33.4% and weak in 17.6% of tumors. TYMS overexpression was associated with deletions at 5q21 (p < 0.0001), 6q15 (p < 0.0001) and 3p13 (p = 0.0083) and gradually increased with the total number of these deletions present in the respective cancer sample (p < 0.0001). TYMS expression was unrelated to PTEN deletions (p = 0.9535) but tightly linked to high Gleason grade, advanced pathological tumor stage and early PSA recurrence (p < 0.0001). The prognostic value of TYMS was independent from the ERG status and deletions at 3p13, 5q21, and 6q15. In multivariate analyses the prognostic role of TYMS expression was independent of Gleason grade, pT stage, preoperative PSA, pN stage, or resection margins. TYMS expression analysis might result in clinically useful information in prostate cancer. The striking link to some but not all chromosomal aberrations might suggest a mechanistical link with specific types of DNA damage.

HOXB13 overexpression is an independent predictor of early PSA recurrence in prostate cancer treated by radical prostatectomy

HOXB13 is a prostate cancer susceptibility gene which shows a cancer predisposing (G84E) mutation in 0.1–0.6% of males. We analyzed the prognostic impact of HOXB13 expression by immunohistochemistry on a tissue microarray containing more than 12,400 prostate cancers. Results were compared to tumor phenotype, biochemical recurrence, androgen receptor (AR) and prostate specific antigen (PSA) as well as molecular subtypes defined by ERG status and genomic deletions of 3p, 5q, 6q, and PTEN. HOXB13 immunostaining was detectable in 51.7% of 10,216 interpretable cancers and considered strong in 9.6%, moderate in 19.7% and weak in 22.3% of cases. HOXB13 expression was linked to advanced pT stage, high Gleason grade, positive lymph node status (p < 0.0001 each), high pre-operative PSA levels (p = 0.01), TMPRSS2:ERG fusion, PTEN deletions, AR expression, cell proliferation, reduced PSA expression and early PSA recurrence (p < 0.0001 each). The prognostic value of HOXB13 was independent from established parameters including Gleason, stage, nodal stage and PSA. Co-expression analysis identified a subset of tumors with high HOXB13 and AR but low PSA expression that had a particularly poor prognosis. HOXB13 appears to be a promising candidate for clinical routine tests either alone or in combination with other markers, including AR and PSA.

Ten-year experience of robot-assisted radical prostatectomy: the road from cherry-picking to standard procedure

BACKGROUND

Patients treated with robot-assisted radical prostatectomy (RARP) are frequently selected according to more favorable characteristics. Such patient selection might decrease according to increasing experience.

METHODS

We relied on the Martini Clinic Prostate Cancer Center database and focused on patients treated with RARP between 2004 and 2013. Differences in clinical, pathological and surgical characteristics at RARP over time (2004-2010, 2011-2012 and 2013) were assessed.

RESULTS

Overall, 1783 RARP patients were identified. Of those, 407 (22.8%), 764 (42.8%) and 612 (34.3%) were treated between 2004 and 2010, in 2011-2012 and in 2013, respectively. Unfavorable characteristics rate, such as biopsy Gleason Score ≥4+4 (8 vs. 9 vs. 15%, P<0.001), D'Amico high-risk (12 vs. 14 vs. 19%, P=0.001) and pathological Gleason score ≥4+4 (3 vs. 4 vs. 6%, P<0.001) increased over time. Pelvic lymph node dissection (PLND) was more frequently performed over time (62 vs. 83 vs. 84%, P<0.001), especially in D'Amico intermediate or high-risk patients (82 vs. 94 vs. 96%, P<0.001). Lymph node yield increased over time in overall (7 vs. 9 vs. 13, P<0.001), D'Amico intermediate (6 vs. 9 vs. 12, P<0.001) and D'Amico high-risk patients (9 vs. 12 vs. 18, P<0.001). No differences in surgical margin (P=0.7) and nerve sparing rates (P=0.09) were found.

CONCLUSIONS

A clear trend towards more unfavorable tumor characteristics over time was recorded. Additionally, the rates and extent of PLND increased with increasing experience. RAR P does not represent a barrier to PLND at our institution.

Cytoplasmic accumulation of ELAVL1 is an independent predictor of biochemical recurrence associated with genomic instability in prostate cancer

BACKGROUND

ELAVL1 is an RNA binding protein involved in translation control, which might have a regulatory role in prostate cancer progress.

METHODS

To evaluate its impact and relationship with key genomic alterations, ELAVL1 expression was analyzed by immunohistochemistry on a tissue microarray containing 12,427 prostate cancers.

RESULTS

The analysis revealed a mild to moderate predominantly nuclear immunostaining in normal prostate epithelium and an often higher both cytoplasmic and nuclear expression in cancer cells. Weak, moderate, and strong cytoplasmic ELAVL1 staining was found in 43%, 18%, and 3% of 10,478 interpretable tumors. Strong ELAVL1 staining was linked to high Gleason grade, advanced pathological tumor stage, positive nodal status, and PSA recurrence (P < 0.0001 each). A combined analysis of the effect of nuclear and cytoplasmic ELAVL1 expression on PSA recurrence revealed that the association with patient outcome was entirely driven by cytoplasmic staining. ELAVL1 positivity was more frequent in cancers harboring TMPRSS2:ERG fusions found by FISH (78%) or showing immunohistochemical ERG expression (74%) than in cancers without ERG rearrangement (63%) or ERG expression (58%, P < 0.0001 each). Strong cytoplasmic ELAVL1 staining was further linked to presence of PTEN, 5q21, 6q15, and 3p13 deletions (P < 0.0001 each), an observation consistent with cytoplasmic ELAVL1 accumulation in case of genomic instability. The prognostic role of ELAVL1 expression was independent of Gleason grade, T stage, N stage, surgical margin status, and preoperative PSA, irrespective of whether preoperative or postoperative variables were used for modeling.

CONCLUSION

Our study identifies cytoplasmic accumulation of ELAVL1 as a predictor of adverse clinical behavior of prostate cancer independent of established clinico-pathological parameters.

The Combination of DNA Ploidy Status and PTEN/6q15 Deletions Provides Strong and Independent Prognostic Information in Prostate Cancer

PURPOSE

Aberrant DNA content has been discussed as a potential prognostic feature in prostate cancer.

EXPERIMENTAL DESIGN

We analyzed the clinical significance of DNA ploidy in combination with prognostic relevant deletions of PTEN and 6q15 in 3,845 prostate cancers.

RESULT

The DNA status was diploid in 67.8%, tetraploid in 25.6%, and aneuploid in 6.8% of tumors, and deletions of PTEN and 6q15 occurred in 17.8% and 20.3% of tumors. Abnormal DNA content and deletions were linked to high Gleason score, advanced tumor stage, and positive nodal stage (P < 0.0001 each). The risk of PSA recurrence increased from diploid to tetraploid and from tetraploid to aneuploid DNA status (P < 0.0001 each). However, 40% of patients with Gleason score ≥4+4 and 55% of patients with PSA recurrence had diploid cancers. This fraction decreased to 21% (Gleason ≥4+4) and 29% (PSA recurrence) if PTEN and/or 6q deletion data were added to ploidy data to identify cancers with an aberrant DNA status. The significance of combining both deletions and ploidy was further demonstrated in a combined recurrence analysis. Presence of deletions increased the risk of PSA recurrence in diploid (P < 0.0001), tetraploid (P < 0.0001), and aneuploid cancers (P = 0.0049), and the combination of ploidy data and deletions provided clinically relevant information beyond the CAPRA-S nomogram. Multivariate modeling including preoperatively and postoperatively available parameters identified the "combined DNA status" as a strong independent predictor of poor patient outcome.

CONCLUSIONS

The combinatorial DNA content analysis involving general (ploidy) and specific events (deletions) has the potential for clinical utility in prostate cancer. Clin Cancer Res; 22(11); 2802-11. ©2016 AACR.

Limited prognostic value of preoperative circulating tumor cells for early biochemical recurrence in patients with localized prostate cancer

INTRODUCTION

The presence of circulating tumor cells (CTCs) is an established marker for prognosis in men with castration-resistant prostate cancer. A cutoff of ≥5 CTCs/7.5ml blood in the CellSearch Epithelial Cell Test has been shown to stratify prognostic groups and predict outcome of abiraterone treatment. In contrast, the value of CTC detection in men with localized prostrate cancer before radical prostatectomy (RP) is unknown.

MATERIALS AND METHODS

A total of 152 patients treated with RP between 06/2009 and 09/2009 were included. Peripheral venous blood drawn the day before RP was evaluated for CTCs by the CellSearch system. The detection of CTCs was correlated with prostate-specific antigen (PSA) and the histopathological outcome of the RP specimen. A cutoff of 0 vs. ≥1 CTC/7.5ml blood was defined as the threshold for positive vs. negative CTC status.

RESULTS

Median age was 62 years and median PSA was 6.7ng/dl. Staging revealed 62.5% pT2, 26.3% pT3a, and 11.2% pT3b tumors, and high-grade disease (≥Gleason 4+3) was determined in 25.6% of patients. CTCs were detected in 17 patients (11%) with a median CTC count/7.5ml of 1 (range: 1-clusters with>100 epithelial cells) without significant correlations to PSA levels, pT stage, or Gleason scores. Postoperative pT stage was a significant predictor of biochemical recurrence (BCR) in univariable logistic regression models and as a composite measure together with positive CTC counts (P<0.0001). CTC positivity alone tended to have a higher hazard ratio for BCR, but this was not statistically significant (P = 0.1). After a median follow-up of 48 months, there was no significant difference in BCR-free survival between patients with or without CTCs (P = 0.7).

CONCLUSION

Using the CellSearch system, we infrequently detected CTCs in patients with localized tumors before RP. The detection of CTCs did not correlate significantly with PSA, disease characteristics, or the development of BCR. However, larger cohorts with extended follow-up are needed to validate our findings.

Clinical Utility of Quantitative Gleason Grading in Prostate Biopsies and Prostatectomy Specimens

BACKGROUND

Gleason grading is the strongest prognostic parameter in prostate cancer. Gleason grading is categorized as Gleason ≤ 6, 3 + 4, 4 + 3, 8, and 9-10, but there is variability within these subgroups. For example, Gleason 4 components may range from 5-45% in a Gleason 3 + 4 = 7 cancer.

OBJECTIVE

To assess the clinical relevance of the fractions of Gleason patterns.

DESIGN, SETTING, AND PARTICIPANTS

Prostatectomy specimens from 12823 consecutive patients and of 2971 matched preoperative biopsies for which clinical data with an annual follow-up between 2005 and 2014 were available from the Martini-Klinik database.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

To evaluate the utility of quantitative grading, the fraction of Gleason 3, 4, and 5 patterns seen in biopsies and prostatectomies were recorded. Gleason grade fractions were compared with prostatectomy findings and prostate-specific antigen recurrence.

RESULTS AND LIMITATIONS

Our data suggest a striking utility of quantitative Gleason grading. In prostatectomy specimens, there was a continuous increase of the risk of prostate-specific antigen recurrence with increasing percentage of Gleason 4 fractions with remarkably small differences in outcome at clinically important thresholds (0% vs 5%; 40% vs 60% Gleason 4), distinguishing traditionally established prognostic groups. Also, in biopsies, the quantitative Gleason scoring identified various intermediate risk groups with respect to Gleason findings in corresponding prostatectomies. Quantitative grading may also reduce the clinical impact of interobserver variability because borderline findings such as tumors with 5%, 40%, or 60% Gleason 4 fractions and very small Gleason 5 fractions (with pivotal impact on the Gleason score) are disclaimed.

CONCLUSIONS

Quantitative Gleason pattern data should routinely be provided in addition to Gleason score categories, both in biopsies and in prostatectomy specimens.

PATIENT SUMMARY

Gleason score is the most important prognostic parameter in prostate cancer, but prone to interobserver variation. The results of our study show that morphological aspects that define the Gleason grade in prostate cancer represent a continuum. Quantitation of Gleason patterns provides clinically relevant information beyond the traditional Gleason grading categories ≤ 3 + 3, 3 + 4, 4 + 3, 8, 9 -1 0. Quantitative Gleason scoring can help to minimize variations between different pathologists and substantially aid in optimized therapy decision-making.

Overexpression of enhancer of zeste homolog 2 (EZH2) characterizes an aggressive subset of prostate cancers and predicts patient prognosis independently from pre- and postoperatively assessed clinicopathological parameters

Enhancer of zeste homolog 2 (EZH2) plays an important role in tumor development and progression by interacting with histone and nonhistone proteins. In the current study, we analyzed prevalence and prognostic impact of EZH2 in prostate cancer. EZH2 expression was analyzed by immunohistochemistry on a tissue microarray containing more than 12400 prostate cancer specimens. Results were compared to tumor phenotype, biochemical recurrence and molecular subtypes defined by ERG status as well as genomic deletions of 3p, 5q, 6q and PTEN. EZH2 immunostaining was detectable in 56.6% of 10168 interpretable cancers and considered strong in 1.1%, moderate in 12.2% and weak in 43.3% of cases. High EZH2 expression was strongly associated with high Gleason grade (P < 0.0001), advanced pathological tumor stage (P < 0.0001), positive nodal status (P < 0.0001), elevated preoperative PSA level (P = 0.0066), early PSA recurrence (P < 0.0001) and increased cell proliferation P < 0.0001). High-level EZH2 staining was also associated with TMPRSS2:ERG rearrangement and ERG expression in prostate cancers (P < 0.0001) and was linked to deletions of PTEN, 6q15, 5q21 and 3p13 (P < 0.0001 each) particularly in ERG-negative cancers. The prognostic impact of EZH2 was independent of established pre- and postoperatively assessed clinicopathological parameters. EZH2 has strong prognostic impact in prostate cancer and might contribute to the development of a fraction of genetically instable and particularly aggressive prostate cancers. EZH2 analysis might therefore be of clinical value for risk stratification of prostate cancer.

Identifying the Most Informative Prediction Tool for Cancer-specific Mortality After Radical Prostatectomy: Comparative Analysis of Three Commonly Used Preoperative Prediction Models

BACKGROUND

The D'Amico risk stratification, Cancer of the Prostate Risk Assessment (CAPRA) score, and Stephenson nomogram are widely used prediction tools for biochemical recurrence and survival after radical prostatectomy (RP). These models have not been compared with respect to cancer-specific mortality (CSM) prediction.

OBJECTIVE

To validate and compare the prediction tools for 10-yr CSM.

DESIGN, SETTING, AND PARTICIPANTS

Overall, 2485 prostate cancer patients underwent RP in a European tertiary care center.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

Three preoperative models (D'Amico, CAPRA, and Stephenson) were compared in terms of their ability to predict 10-yr CSM; therefore, accuracy tests (area under the receiver operating characteristic curve [AUC]), calibration plots, and decision curve analysis (DCA) were assessed for each model.

RESULTS AND LIMITATIONS

CSM at 10 yr was 3.6%. The AUC was 0.76, 0.77, and 0.80 for the D'Amico, CAPRA, and Stephenson models, respectively. In calibration plots, predicted probabilities were close to the observed probabilities for the D'Amico model but showed underestimation of CSM for the Stephenson nomogram and overestimation of CSM for the CAPRA score. DCA identified a benefit for the CAPRA score. These results apply to patients treated at a European tertiary care center.

CONCLUSIONS

Despite good discriminatory power, all tested models had some shortcomings in terms of prediction of 10-yr CSM. All three models showed good performance in North American cohorts, but our results suggested a lack of generalizability to European patients. To overcome this issue, local recalibration of the variable weights could be performed. Another possibility is the development of more universal markers that are independent of regional practice differences or, alternatively, the development of better tools to quantify clinical practice differences.

PATIENT SUMMARY

Prediction tools can predict cancer survival prior surgery, relying on points for age, prostate-specific antigen levels, aggressiveness, and percentage of cancer at biopsy. These tools are reliable in North American patients but have shortcomings for identifying patients at high risk of prostate cancer death in Europe.

The prognostic value of SUMO1/Sentrin specific peptidase 1 (SENP1) in prostate cancer is limited to ERG-fusion positive tumors lacking PTEN deletion

Background

Posttranscriptional protein modification by SUMOylation plays an important role in tumor development and progression. In the current study we analyzed prevalence and prognostic impact of the de-SUMOylation enzyme SENP1 in prostate cancer.

Methods

SENP1 expression was analyzed by immunohistochemistry on a tissue microarray containing more than 12,400 prostate cancer specimens. Results were compared to tumor phenotype, ERG status, genomic deletions of 3p, 5q, 6q and PTEN, and biochemical recurrence.

Results

SENP1 immunostaining was detectable in 34.5 % of 9,516 interpretable cancers and considered strong in 7.3 %, moderate in 14.9 % and weak in 12.3 % of cases. Strong SENP1 expression was linked to advanced pT stage (p < 0.0001), high Gleason grade (p < 0.0001), positive lymph node status (p = 0.0019), high pre-operative PSA levels (p = 0.0037), and PSA recurrence (p < 0.0001). SENP1 expression was strongly associated with positive ERG fusion status as determined by both in situ hybridization (FISH) and immunohistochemistry as well as with PTEN deletions. Detectable SENP1 immunostaining was found in 41 % of ERG positive and in 47 % of PTEN deleted cancers but in only 30 % of ERG negative and 30 % of PTEN non-deleted cancers (p < 0.0001 each). Deletions of 3p, 5q, and 6q were unrelated to SENP1 expression. Subset analyses revealed that the prognostic impact of SENP1 expression was solely driven by the subgroup of ERG positive, PTEN undeleted cancers. In this subgroup, the prognostic role of SENP1 expression was independent of the preoperative PSA level, tumor stage, Gleason grade, and the status of the resection margin.

Conclusions

SENP1 expression has strong prognostic impact in a molecularly defined subset of cancers. This is per se not surprising as the biologic impact of each individual molecular event is likely to be dependent on its cellular environment. However, such findings challenge the concept of finding clinically relevant molecular signatures that are equally applicable to all prostate cancers.

Electronic supplementary material

The online version of this article (doi:10.1186/s12885-015-1555-8) contains supplementary material, which is available to authorized users.

Initial Experience of (68)Ga-PSMA PET/CT Imaging in High-risk Prostate Cancer Patients Prior to Radical Prostatectomy

Prostate-specific membrane antigen (PSMA) overexpression theoretically enables targeting of prostate cancer (PCa) metastases using gallium Ga 68 ((68)Ga)-labeled PSMA ligands for positron emission tomography/computed tomography (PET/CT) imaging. Promising detection rates have been reported when using this approach for functional imaging of recurrent PCa; however, until now, the diagnostic accuracy of (68)Ga-PSMA PET/CT for preoperatively identifying lymph node metastases (LNMs) had not been assessed. We retrospectively compared preoperative (68)Ga-PSMA PET/CT lymph node (LN) findings with histologic work-up after radical prostatectomy (RP). Overall, 608 LNs containing 53 LNMs were detected during RP. LNMs were present in 12 of 30 patients (40%). The (68)Ga-PSMA PET/CT scans identified 4 patients (33.3%) as LN true positive and 8 patients (66.7%) as false negative. Median size of (68)Ga-PSMA-PET/CT-detected versus undetected LNMs was 13.6 versus 4.3 mm (p<0.05). Overall sensitivity, specificity, positive predictive value, and negative predictive value of (68)Ga-PSMA PET/CT for LNM detection were 33.3%, 100%, 100%, and 69.2%, respectively. Per-side analyses revealed corresponding values of 27.3%, 100%, 100%, and 52.9%. Conversely, (68)Ga-PSMA PET/CT enabled tumor visualization in the prostate. In 92.9% of patients, the intraprostatic tumor foci were correctly predicted. Overall, (68)Ga-PSMA PET/CT is a promising tool for functional imaging; however, our initial experience revealed substantial influence of LNM size on the diagnostic accuracy of (68)Ga-PSMA PET/CT.

PATIENT SUMMARY

We assessed the diagnostic accuracy of (68)Ga-PSMA PET/CT in high-risk prostate cancer patients prior to radical prostatectomy. We found that lymph node metastasis detection rates were substantially influenced by lymph node metastasis size.

Adherence of the indication to European Association of Urology guideline recommended pelvic lymph node dissection at a high-volume center: Differences between open and robot-assisted radical prostatectomy

PURPOSE

Contemporary adherence of the indication to European Association of Urology (EAU) guideline recommendation for pelvic lymph node dissection (PLND) at either open (ORP) or robot-assisted radical prostatectomy (RARP) at a high-volume center is unknown. To assess guideline recommended and observed PLND rates in a high-volume center cohort.

METHODS

We relied on the Martini-Clinic database and focused on patients treated with either ORP or RARP, between 2010 and 2013. Actual performed PLND was compared to European Association of Urology (EAU) guideline recommendation defined by nomogram predicted risk of lymph node invasion >5%. Categorical and multivariable logistic regression analyses targeted two endpoints: 1) probability of guideline recommended PLND and 2) probability of no PLND, when not recommended by EAU guideline.

RESULTS

Within 7868 PCa patients, adherence to EAU PLND guideline recommendation was 97.1% at ORP and 96.8% at RARP (p = 0.7). When PLND was not recommended, it was more frequently performed at RARP (71.6%) than at ORP (66.2%) (p = 0.002). Gleason score, PSA and number of positive biopsy cores were independent predictors for both either PLND when recommended, or no PLND when not recommended (all p < 0.05). Clinical tumor stage, age and surgical approach were also independent predictors for no PLND when not recommended (all p < 0.05).

CONCLUSIONS

Adherence of the indication to EAU guideline recommended PLND is high at this high-volume center. Neither ORP nor RARP represent a barrier for PLND, when recommended. However, a high number of patients underwent PLND despite absence of guideline recommendation. Possible staging advantages and PLND related complications needs to be individually considered, especially, when LNI risk is low.

Loss of SOX9 Expression Is Associated with PSA Recurrence in ERG-Positive and PTEN Deleted Prostate Cancers

The transcription factor SOX9 plays a crucial role in normal prostate development and has been suggested to drive prostate carcinogenesis in concert with PTEN inactivation. To evaluate the clinical impact of SOX9 and its relationship with key genomic alterations in prostate cancer, SOX9 expression was analyzed by immunohistochemistry on a tissue microarray containing 11,152 prostate cancers. Data on ERG status and deletions of PTEN, 3p13, 5q21 and 6q15 were available from earlier studies. SOX9 expression levels were comparable in luminal cells of normal prostate glands (50% SOX9 positive) and 3,671 cancers lacking TMPRSS2:ERG fusion (55% SOX9 positive), but was markedly increased in 3,116 ERG-fusion positive cancers (81% SOX9 positive, p<0.0001). While no unequivocal changes in the SOX9 expression levels were found in different stages of ERG-negative cancers, a gradual decrease of SOX9 paralleled progression to advanced stage, high Gleason grade, metastatic growth, and presence of PTEN deletions in ERG-positive cancers (p<0.0001 each). SOX9 levels were unrelated to deletions of 3p, 5q, and 6q. Down-regulation of SOX9 expression was particularly strongly associated with PSA recurrence in ERG-positive tumors harboring PTEN deletions (p=0.001), but had no significant effect in ERG-negative cancers or in tumors with normal PTEN copy numbers. In summary, the results of our study argue against a tumor-promoting role of SOX9 in prostate cancer, but demonstrate that loss of SOX9 expression characterizes a particularly aggressive subset of ERG positive cancers harboring PTEN deletions.

Cytoplasmic Accumulation of Sequestosome 1 (p62) Is a Predictor of Biochemical Recurrence, Rapid Tumor Cell Proliferation, and Genomic Instability in Prostate Cancer

PURPOSE

Sequestosome 1 (p62) is a multifunctional adapter protein accumulating in autophagy-defective cells.

EXPERIMENTAL DESIGN

To evaluate the clinical impact and relationship with key genomic alterations in prostate cancer, p62 protein levels were analyzed by immunohistochemistry on a tissue microarray containing 12,427 prostate cancers. Data on ERG status and deletions of PTEN, 3p13, 5q21, and 6q15 were available from earlier studies.

RESULTS

p62 immunostaining was absent in benign prostatic glands but present in 73% of 7,822 interpretable prostate cancers. Strong cytoplasmic p62 staining was tightly linked to high Gleason grade, advanced pathologic tumor (pT) stage, positive nodal status, positive resection margin, and early PSA recurrence (P < 0.0001 each). Increased levels of p62 were significantly linked to TMPRSS2-ERG fusions, both by FISH and immunohistochemical analysis (P < 0.0001 each). For example, moderate or strong p62 immunostaining was seen in 28.5% of cancers with TMPRSS2-ERG fusion detected by FISH and in 23.1% of cancers without such rearrangements (P < 0.0001). Strong p62 staining was significantly linked to the presence of all tested deletions, including PTEN (P < 0.0001), 6q15 (P < 0.0001), 5q21 (P = 0.0002), 3p13 (P = 0.0088), and 6q15 (P < 0.0001), suggesting a link between p62 accumulation and loss of genomic stability. The prognostic role of p62 protein accumulation was striking and independent of Gleason grade, pT stage, pN stage, surgical margin status, and preoperative PSA, regardless of whether preoperative or postoperative parameters were used for modeling.

CONCLUSIONS

Our study identifies cytoplasmic accumulation of p62 as a strong predictor of an adverse prognostic behavior of prostate cancer independently from established clinicopathologic findings.

Redefining postprostatectomy biochemical progression: The significance of a PSA cutoff below 0.2 ng/ml—Results from two retrospective series with and without salvage radiotherapy

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Background: Biochemical recurrence (BCR) after radical prostatectomy (RP) is usually defined at a PSA >0.2 ng/ml. BCR may precede clinical progression by years. Though salvage radiotherapy (SRT) is recommend to be initiated at PSA <0.5 ng/ml, its efficiency at PSA <0.2 ng/ml is not well documented. Methods: We relied on two independent post-RP cohorts. Cohort 1 (n=311, Hamburg) comprised men whose post-RP PSA levels had risen to 0.1-0.2 ng/ml. Further biochemical and clinical progression were recorded during follow-up. Cohort 2 (n=198, Berlin) were patients with BCR who received SRT (66/72 Gy) at a PSA <0.5 ng/ml. The median follow-up was 6.9 years. Post-SRT progression and overall survival were addressed by Kaplan-Meier analysis and Cox regression modelling. Results: In cohort 1, 299 (96%) men experienced further PSA progression (>0.2 ng/ml) within a median time of 7 months. Subsequent PSA rise to >0.3, >0.4, and >0.6 ng/ml was recorded in 174 (58%), 123 (41%), and 24 (8%) men, respectively. Twenty-four (8%) men developed metastases. In cohort 2, 112 men received SRT at PSA between 0.03 and 0.2 ng/ml, and 86 at 0.2-0.499 ng/ml. The latter group, had a poorer 10-years BCR-free Kaplan-Meier rate, 43% vs. 66% (p=0.051). Together with pT<3, Gleason Score <7, and post-RP PSA <0.03 ng/ml, SRT at PSA <0.2 ng/ml was an independent favorable predictor of freedom from BCR (OR=0.60, p<0.05). Ultimately, 14 patients died. However, overall survival did not significantly correlate with the pre-SRT PSA. Conclusions: The vast majority of patients with a PSA >0.1 ng/ml after RP will subsequently progress to PSA >0.2 ng/ml. Improved progression free survival can be achieved, if SRT is administered at a PSA <0.2 ng/ml. Therefore the contemporary PSA threshold for defining BCR after RP needs to be reconsidered and early sRT should be contemplated on a individual basis for optimizing oncological outcomes.

Biomodulatory Treatment of Patients with Castration-Resistant Prostate Cancer: A Phase II Study of Imatinib with Pioglitazone, Etoricoxib, Dexamethasone and Low-Dose Treosulfan

Therapeutic options for patients with castration-resistant prostate cancer (CRPC) remain limited. In a multicenter, Phase II study, 65 patients with histologically confirmed CRPC received a biomodulatory regimen during the six-month core study. Treatment comprised daily doses of imatinib mesylate, pioglitazone, etoricoxib, treosulfan and dexamethasone. The primary endpoint was prostate-specific antigen (PSA) response. Responders could enter an extension phase until disease progression or intolerable toxicity occurred. Mean PSA was 45.3 ng/mL at baseline, and 77 % of patients had a PSA doubling time <3 months. Of the 61 evaluable patients, 37 patients (60.6 %) responded or had stable disease and 23 of them (37.7 % of 61 patients) were PSA responders. Among the 23 responders mean PSA decreased from 278.9 ± 784.1 ng/mL at baseline to 8.8 ± 11.6 ng/mL at the final visit (week 24). The progression-free survival (PFS) was 467 days in the ITT population. Of the 947 adverse events, 57.6 % were suspected to be drug-related, 13.8 % led to dose adjustment or permanent discontinuation and 40.2 % required concomitant medication. This novel combination approach led to an impressive PSA response rate of 37.7 % in CRPC patients. The good PSA response and PFS rate combined with the manageable toxicity profile suggest an alternative treatment option.

Abstract 567: Multiparametric analysis of an ultra-large prostate cancer tissue microarray with attached histo-pathological, clinical, and molecular data: A tool for rapid evaluation of clinically relevant gene sets

A magnitude of candidate prognostic markers has been suggested in prostate cancer during the last decade. However, virtually none of these markers has been proven to be sufficiently reliable to justify development a new routine diagnostic applications. It is hoped that combinations of multiple markers will allow for an improved prediction of the clinical behavior of theses tumors. In order

In order to create a platform for rapid validation of the clinical impact of a large number of candidate prognostic markers and their combinations, we have constructed a tissue microarray containing 12,427 individual prostate cancers undergoing radical prostatectomy between 1992 and 2012, and assembled a database with detailed histological, pathological, and clinical follow-up data. More than 60 molecular parameters have been analyzed by means of immunohistochemistry (IHC) and/or fluorescence in situ hybridization (FISH) in this cancer set until today, including such that have been suggested for candidate prognosticator before as well as novel markers. Integrated analysis of these markers revealed prognostic relevant patterns of specific alterations, including a 10-genes classifier that predicted biochemical recurrence independently from established prognostic factors pathological stage, nodal stage, pre-surgical prostate specific antigen levels, Gleason grade, and status of the resection margin. We also found that the number of deletions per cancer had strong prognostic relevance.

In summary, our data demonstrate the power of our prostate cancer tissue microarray platform for long term analysis of dozens of putative prognosticators on the DNA and protein level on the same tissue set with detailed clinical characterization. Despite only one tissue core per tumor has been sampled, this platform has proven to be instrumental for validation of the clinical impact of known and suggested prognosis markers. The very high number of individual samples even allows for multiparametric analysis resulting in the identification of marker sets that are superior to established prognostic parameters.

Citation Format: Martina Kluth, Maria Christina Tsourlakis, Claudia Hube-Magg, Christoph Burdelski, Katharina Grupp, Hartwig Huland, Hans Heinzer, Markus Graefen, Stefan Steurer, Ronald Simon, Thorsten Schlomm, Guido Sauter, Sarah Minner. Multiparametric analysis of an ultra-large prostate cancer tissue microarray with attached histo-pathological, clinical, and molecular data: A tool for rapid evaluation of clinically relevant gene sets. [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 567. doi:10.1158/1538-7445.AM2014-567

Abstract 2216: 6q15 deletion impede development of ERG fusion in prostate cancer

Deletions at chromosome 6q15 belong one to the most frequent alterations in pros-tate cancer, and are linked to poor prognosis. Furthermore, there is a marked inverse relationship between 6q15 deletions and TMPRSS2:ERG fusions in prostate cancer. While heterogeneity may limit the applicability of diagnostic molecular markers, it is important to estimate in vivo heterogeneity and the sequel of appearance of potential prognostic markers. In case of one alteration developing after the other, we would expect a small area of cancer having both alterations within a larger area having only one (the first appearing) of these changes.

In this study, we used our heterogeneity tissue microarray approach as a surrogate method to determine in vivo heterogeneity of 6q15 deletions and TMPRSS2:ERG fusions. We constructed a heterogeneity TMA containing samples taken from 10 dif-ferent tumor containing tissue blocks of 189 prostate cancers. Each prostate con-tained 1 to 6 individual cancer foci allowing the molecular analysis of more than 350 tumor foci. 6q15 deletion was analyzed by fluorescence in situ hybridization and ERG expression by immunohistochemistry.

Only 6.6% of 334 ERG positive but 28.4% of 440 ERG negative TMA spots showed 6q15 deletions (p&lt;0.0001). A breakdown of these data to the level of tumor foci re-vealed 6q deletions in 34 tumor foci that were large enough to have at least 3 ana-lyzable TMA spots. The cohort included 42 tumor foci with a homogeneous ERG pos-itivity and 15 with a homogeneous 6q deletion. Remarkably, six of 42 homogeneously ERG positive tumor foci (14.3%) were focal 6q15-deleted, but none of 16 homogene-ous 6q15-deleted foci showed focal ERG positivity in the same tumor area (p=0.022).

In conclusion of our study, the complete absence of ERG positive tumor foci in 6q15-deleted cancers suggests that the functional consequences of 6q15 deletions may prevent the development of TMPRSS2:ERG fusions. However, the development of 6q15 deletions is independent of the ERG status.

Citation Format: Martina Kluth, Maria Christina Tsourlakis, David Meyer, Antje Krohn, Fabian Freudenthaler, Melanie Bauer, Georg Salomon, Hans Heinzer, Uwe Michl, Stefan Steurer, Ronald Simon, Guido Sauter, Thorsten Schlomm, Sarah Jane Pauline Minner. 6q15 deletion impede development of ERG fusion in prostate cancer. [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 2216. doi:10.1158/1538-7445.AM2014-2216

Open and robot-assisted radical retropubic prostatectomy in men receiving ongoing low-dose aspirin medication: revisiting an old paradigm?

OBJECTIVE

To assess blood loss, transfusion rates and 90-day complication rates in patients receiving ongoing 100 mg/day aspirin medication and undergoing open radical prostatectomy (RP) or robot-assisted RP (RARP).

PATIENTS AND METHODS

Between February 2010 and August 2011, 2061 open RPs and 400 RARPs were performed. All patients received low-molecular-weight heparin for thrombembolism prophylaxis. Aspirin intake during surgery was recorded in 137 patients (5.5%). Descriptive statistics and multivariable analyses after propensity-score matching for balancing potential differences in patients with and without aspirin medication were used to assess the risk of blood loss above the median in patients undergoing open RP or RARP.

RESULTS

The median blood loss in the open RP cohort with and without aspirin medication was 750 and 700 mL, respectively, and in the RARP cohort it was 200 and 150 mL, respectively. Within the same cohorts, transfusions were administered in 21 and 8% and 0 and 1% of patients, respectively. The 90-day complication rates in patients with ongoing aspirin medication were 5.8, 4.4, 7.3 and 0% for Clavien grades I, II, III and IV complications, respectively. In multivariable analyses and after propensity-score matching, prostate volume (odds ratio 1.03; 95% CI 1.02-1.04; P < 0.01) but not ongoing aspirin medication achieved independent predictor status for the risk of blood loss above the median.

CONCLUSIONS

Major surgery such as open RP and RARP can be safely performed in patients with ongoing aspirin medication without greater blood loss. Higher 90-day complication rates were not detected in such patients. Differences in transfusion rates between the groups receiving and not receiving ongoing aspirin medication may be explained by a higher proportion of patients with coronary artery disease in the group receiving ongoing aspirin medication. This comorbidity may result in a higher peri-operative threshold for allogenic blood transfusion.