Stratification of patients with intermediate-risk prostate cancer

Clinical Predictors of Grade Group Upgrading for Radical Prostatectomy Specimens Compared to Those of Preoperative Needle Biopsy Specimens

BACKGROUND

Decision-making and selection of treatment modalities for newly diagnosed prostate cancer (PCa) are often determined by risk stratification using grade group (GG), prostate-specific antigen (PSA), and clinical stage. The discrepancies between needle biopsy (NB) and radical prostatectomy (RP) specimens often occur because of the sampling errors in NB or multifocal features of PCa. Thus, we aimed to estimate the preoperative clinical factors for predicting GG upgrading after robot-assisted RP (RARP).

METHODS

In this retrospective study, we reviewed the clinical and pathological records of patients who underwent RARP at Gifu University Hospital. We focused on patients with organ-confined PCa who had not received neoadjuvant therapy prior to RARP. The primary endpoint was identified as the predictive factor of GG upgrading for RARP specimens compared to those of NB specimens.

RESULTS

Eighty-one patients were included in this study. The enrolled patients were divided into two groups: those who had GG upgrading for RARP specimens (the NB upgrade group) or those who did not have GG upgrading (the no upgrade group). The median age of all patients was 70 years, and the median body mass index (BMI) was 22.9 kg/m². The median neutrophil count was 3720/μL, lymphocyte count was 1543/μL, and neutrophil-to-lymphocyte ratio (NLR) was 2.24. In univariate analysis, BMI, PSA, neutrophil count, and NLR were significantly associated with GG upgrading in RARP specimens compared to NB specimens. BMI and NLR were identified as strong predictive factors for GG upgrading in RARP specimens in the multivariate analysis.

CONCLUSIONS

Although this study's small number of enrolled patients was a vital weakness, BMI and NLR might have been significantly correlated with GG upgrading for RP specimens compared with NB specimens. Therefore, BMI and NLR may have potential benefits for newly diagnosed patients with PCa in terms of decision-making and the selection of treatment modalities.

The Impact of Gleason Grade 3 as a Predictive Factor for Biochemical Recurrence after Robot-Assisted Radical Prostatectomy: A Retrospective Multicenter Cohort Study in Japan (The MSUG94 Group)

Background and Objectives: This study’s objective was to examine patients treated with robot-assisted radical prostatectomy (RARP) for intermediate-risk prostate cancer (IR-PCa), and to identify preoperative risk factors for biochemical recurrence (BCR) in these patients in Japan. Materials and Methods: We conducted a retrospective multicenter cohort study of patients with PCa who underwent RARP at 10 institutions in Japan. A total of 3195 patients were enrolled in this study. We focused on patients with IR-PCa who underwent RARP. We obtained data on pre- and postoperative covariates from the enrolled patients. Biochemical recurrence-free survival was the primary endpoint of this study. We also identified useful preoperative predictive factors for BCR in patients with IR-PCa after RARP. Results: A total of 1144 patients with IR-PCa were enrolled in this study. The median follow-up period was 23.7 months. At the end of the follow-up period, 94 (8.2%) patients developed BCR. The 2 and 3 year biochemical recurrence-free survival (BRFS) rates were 92.2% and 90.2%, respectively. Using the Kaplan–Meier method, Gleason grade (GG) 3 was significantly associated with poor BRFS compared with ≤GG 2. In multivariate analysis, GG 3 was a significant predictive factor for BCR in patients with IR-PCa. Conclusions: The results of the study indicated a significant relationship between GG 3 and post-RARP BCR in patients with IR-PCa.

Results of the IROCA international clinical audit in prostate cancer radiotherapy at six comprehensive cancer centres

To assess adherence to standard clinical practice for the diagnosis and treatment of patients undergoing prostate cancer (PCa) radiotherapy in four European countries using clinical audits as part of the international IROCA project. Multi-institutional, retrospective cohort study of 240 randomly-selected patients treated for PCa (n = 40/centre) in the year 2015 at six European hospitals. Clinical indicators applicable to general and PCa-specific radiotherapy processes were evaluated. All data were obtained directly from medical records. The audits were performed in the year 2017. Adherence to clinical protocols and practices was satisfactory, but with substantial inter-centre variability in numerous variables, as follows: staging MRI (range 27.5-87.5% of cases); presentation to multidisciplinary tumour board (2.5-100%); time elapsed between initial visit to the radiation oncology department and treatment initiation (42-102.5 days); number of treatment interruptions ≥ 1 day (7.5-97.5%). The most common deviation from standard clinical practice was inconsistent data registration, mainly failure to report data related to diagnosis, treatment, and/or adverse events. This clinical audit detected substantial inter-centre variability in adherence to standard clinical practice, most notably inconsistent record keeping. These findings confirm the value of performing clinical audits to detect deviations from standard clinical practices and procedures.

Favorable intermediate risk prostate cancer with biopsy Gleason score of 6

BACKGROUND

To identify potential prognostic factors among patients with favorable intermediate risk prostate cancer with a biopsy Gleason score 6.

METHODS

From 2003 to 2019, favorable intermediate risk patients who underwent radical prostatectomy were included in this study. All patients were evaluated preoperatively with MRI. Using PI-RADS scores, patients were divided into two groups, and clinic-pathological outcomes were compared. The impact of preoperative factors on significant pathologic Gleason score upgrading (≥ 4 + 3) and biochemical recurrence were assessed via multivariate analysis. Subgroup analysis was performed in patients with PI-RADS ≤ 2.

RESULTS

Among the 239 patients, 116 (48.5%) were MRI-negative (PI-RADS ≤ 3) and 123 (51.5%) were MRI-positive (PI-RADS > 3). Six patients in the MRI-negative group (5.2%) were characterized as requiring significant pathologic Gleason score upgrading compared with 34 patients (27.6%) in the MRI-positive group (p < 0.001). PI-RADS score was shown to be a significant predictor of significant pathologic Gleason score upgrading (OR = 6.246, p < 0.001) and biochemical recurrence (HR = 2.595, p = 0.043). 10-years biochemical recurrence-free survival was estimated to be 84.4% and 72.6% in the MRI-negative and MRI-positive groups (p = 0.035). In the 79 patients with PI-RADS ≤ 2, tumor length in biopsy cores was identified as a significant predictor of pathologic Gleason score (OR = 11.336, p = 0.014).

CONCLUSIONS

Among the patients with favorable intermediate risk prostate cancer with a biopsy Gleason score 6, preoperative MRI was capable of predicting significant pathologic Gleason score upgrading and biochemical recurrence. Especially, the patients with PI-RADS ≤ 2 and low biopsy tumor length could be a potential candidate to active surveillance.

A Novel Predictor Tool of Biochemical Recurrence after Radical Prostatectomy Based on a Five-MicroRNA Tissue Signature

Within five to ten years after radical prostatectomy (RP), approximately 15–34% of prostate cancer (PCa) patients experience biochemical recurrence (BCR), which is defined as recurrence of serum levels of prostate-specific antigen >0.2 µg/L, indicating probable cancer recurrence. Models using clinicopathological variables for predicting this risk for patients lack accuracy. There is hope that new molecular biomarkers, like microRNAs (miRNAs), could be potential candidates to improve risk prediction. Therefore, we evaluated the BCR prognostic capability of 20 miRNAs, which were selected by a systematic literature review. MiRNA expressions were measured in formalin-fixed, paraffin-embedded (FFPE) tissue RP samples of 206 PCa patients by RT-qPCR. Univariate and multivariate Cox regression analyses were performed, to assess the independent prognostic potential of miRNAs. Internal validation was performed, using bootstrapping and the split-sample method. Five miRNAs (miR-30c-5p/31-5p/141-3p/148a-3p/miR-221-3p) were finally validated as independent prognostic biomarkers. Their prognostic ability and accuracy were evaluated using C-statistics of the obtained prognostic indices in the Cox regression, time-dependent receiver-operating characteristics, and decision curve analyses. Models of miRNAs, combined with relevant clinicopathological factors, were built. The five-miRNA-panel outperformed clinically established BCR scoring systems, while their combination significantly improved predictive power, based on clinicopathological factors alone. We conclude that this miRNA-based-predictor panel will be worth to be including in future studies.

Comparison between Zumsteg classification and Briganti nomogram for the risk of lymph-node invasion before radical prostatectomy

PURPOSE

To evaluate the performance of the Zumsteg classification to estimate the risk of lymph-node invasion (LNI) compared with the Briganti nomogram (BN) in prostatectomy patients with intermediate-risk prostate cancer (IRPC).

METHODS

We included consecutive patients who had extended pelvic lymph-node dissection associated with radical prostatectomy for IRPC. To be classified favorable intermediate risk (FIR), patients could only have one intermediate-risk factor, fewer than 50% positive biopsies and no primary Gleason score of 4.

RESULTS

On the 387 patients included, 149 (38.5%) and 238 (54.3%) were classified FIR and unfavorable intermediate risk (UIR), respectively, and 212 (54.8%) had a BN inferior to 5%. Thirty-eight patients (9.8%) had LNI: 6 FIR patients (4.0%) versus 32 UIR patients (13.4%) and 14 patients (6.6%) with a BN inferior to 5% versus 24 patients (13.7%) with a BN superior to 5%. Eight patients with a BN inferior to 5%, but classified UIR, had LNI. Sensitivity to detect LNI was higher with the Zumsteg classification than with the BN: 84.2% (CI 95% [68-93]) versus 63.2% (CI 95% [46-78]). Both screening tests were concordant to predict LNI (kappa coefficient of 0.076, p < 0.05 for Zumsteg and Briganti) CONCLUSIONS: Zumsteg classification appeared to be more sensitive and as effective (despite the impossibility to make decision curve analysis) than the BN to estimate the risk of LNI. Regarding the modest number of pN+ patients, further studies are needed to see the interest of proposing ePLND for UIR patients only.

The Association of the Long Prostate Cancer Expressed PDE4D Transcripts to Poor Patient Outcome Depends on the Tumour's TMPRSS2-ERG Fusion Status

Objectives

To investigate the added value of assessing transcripts for the long cAMP phosphodiesterase-4D (PDE4D) isoforms, PDE4D5 and PDE4D9, regarding the prognostic power of the ‘CAPRA & PDE4D7' combination risk model to predict longitudinal postsurgical biological outcomes in prostate cancer.

Patients and Methods

RNA was extracted from both biopsy punches of resected tumours (606 patients; RP cohort) and diagnostic needle biopsies (168 patients; DB cohort). RT-qPCR was performed in order to determine PDE4D5, PDE4D7, and PDE4D9 transcript scores in both study cohorts. By RNA sequencing, we determined the TMPRSS2-ERG fusion status of each tumour sample in the RP cohort. Kaplan-Meier survival analyses were then applied to correlate the PDE4D5, PDE4D7 and PDE4D9 scores with postsurgical patient outcomes. Logistic regression was then used to combine the clinical CAPRA score with PDE4D5, PDE4D7, and PDE4D9 scores in order to build a ‘CAPRA & PDE4D5/7/9' regression model. ROC and decision curve analysis was used to estimate the net benefit of the ‘CAPRA & PDE4D5/7/9' risk model.

Results

Kaplan-Meier survival analysis, on the RP cohort, revealed a significant association of the PDE4D7 score with postsurgical biochemical recurrence (BCR) in the presence of the TMPRSS2-ERG gene rearrangement (logrank p<0.0001), compared to the absence of this gene fusion event (logrank p=0.08). In contrast, the PDE4D5 score was only significantly associated with BCR in TMPRSS2-ERG fusion negative tumours (logrank p<0.0001 vs. logrank p=0.4 for TMPRSS2-ERG+ tumours). This was similar for the PDE4D9 score although less pronounced compared to that of the PDE4D5 score (TMPRSS2ERG- logrank p<0.0001 vs. TMPRSS2ERG+ logrank p<0.005). In order to predict BCR after primary treatment, we undertook ROC analysis of the logistic regression combination model of the CAPRA score with the PDE4D5, PDE4D7, and PDE4D9 scores. For the DB cohort, this demonstrated significant differences in the AUC between the CAPRA and the PDE4D5/7/9 regression model vs. the CAPRA and PDE4D7 risk model (AUC 0.87 vs. 0.82; p=0.049) vs. the CAPRA score alone (AUC 0.87 vs. 0.77; p=0.005). The CAPRA and PDE4D5/7/9 risk model stratified 19.2% patients of the DB cohort to either ‘no risk of biochemical relapse' (NPV 100%) or the ‘start of any secondary treatment (NPV 100%)', over a follow-up period of up to 15 years. Decision curve analysis presented a clear, net benefit for the use of the novel CAPRA & PDE4D5/7/9 risk model compared to the clinical CAPRA score alone or the CAPRA and PDE4D7 model across all decision thresholds.

Conclusion

Association of the long PDE4D5, PDE4D7, and PDE4D9 transcript scores to prostate cancer patient outcome, after primary intervention, varies in opposite directions depending on the TMPRSS2-ERG genomic fusion background of the tumour. Adding transcript scores for the long PDE4D isoforms, PDE4D5 and PDE4D9, to our previously presented combination risk model of the combined ‘CAPRA & PDE4D7' score, in order to generate the CAPRA and PDE4D5/7/9 score, significantly improves the prognostic power of the model in predicting postsurgical biological outcomes in prostate cancer patients.

Index tumor volume on MRI as a predictor of clinical and pathologic outcomes following radical prostatectomy

PURPOSE

Index tumor volume (ITV) measured on radical prostatectomy (RP) specimens has been shown to be associated with adverse pathologic and oncologic outcomes. We evaluate the value of ITV calculated from prostate multiparametric MRI (mpMRI) in predicting adverse clinical and pathologic outcomes.

MATERIALS AND METHODS

Data from a prospectively maintained, single-institution database were analyzed for patients who underwent mpMRI prior to RP (2007-2016). Index tumor was defined as a T2-visible lesion with the longest diameter. Adverse pathologic outcomes were extraprostatic extension (EPE), lymph node invasion (LNI), seminal vesicle invasion (SVI), and positive margins (PM). Logistic and Cox proportional hazard regression were used to assess associations with adverse pathology and biochemical recurrence (BCR), respectively.

RESULTS

Of the 455 patients included, EPE, LNI, SVI and PM were present in 23.5%, 6.2%, 5.5% and 15.7% patients, respectively. Patients with adverse pathologic outcomes had larger median ITV. ITV was found to be an independent predictor of EPE (OR 1.22, p = 0.010), LNI (OR 1.39, p = 0.001), and SVI (OR 1.28, p = 0.009), but not PM (OR 1.03, p = 0.522). Combination of ITV and PSA was found to have predictive ability comparable to that of modified Partin tables (EPE:ITV + PSA_AUC = 0.71 vs. Partin_AUC = 0.71; LNI:ITV + PSA_AUC = 0.92 vs. Partin_AUC = 0.90, SVI:ITV + PSA_AUC = 0.78 vs. Partin_AUC = 0.82). 5 year BCR-free survival (median follow-up 24.9 months) was higher for patients with ITV < 2 cc (84.1% vs. 58.5%, p = 0.001). However, ITV was not found to be an independent predictor of BCR (HR 1.69, p = 0.130).

CONCLUSIONS

We demonstrate that ITV measured on mpMRI is a predictor of adverse pathologic and clinical outcomes and can aid in preoperative risk assessment.

Performance characteristics of prostate-specific antigen density and biopsy primary Gleason score to predict biochemical failure in patients with intermediate prostate cancer who underwent radical prostatectomy

Background

Prognosis for intermediate-risk prostate cancer (PCa) remains variable; therefore, we aimed to investigate high-risk factors for biochemical recurrence (BCR), and intermediate-risk PCa using radical prostatectomy to identify patients having equivalent BCR-free survival rates when compared to high-risk PCa.

Patients and methods

A total of 441 medical records were analyzed, including those of 169 intermediate-risk and 272 high-risk PCa patients. Risk factors for time to BCR were tested and analyzed using Kaplan–Meier survival analysis, log-rank tests, and Cox proportion hazards models.

Results

In the intermediate-risk group, prostate-specific antigen density (PSAD) and primary Gleason pattern were significant preoperative risk factors for BCR. Moreover, BCR-free survival of patients in the intermediate-risk group with a higher PSAD (>0.5 ng/mL/cm³) was comparable with that of patients in the high-risk group (P=0.735). When combining primary Gleason pattern 4 and 3 with PSAD cut-offs 0.3–0.7 ng/mL/cm³, we found that BCR-free survival of patients in the intermediate-risk group with a primary Gleason pattern 4 and PSAD >0.3 ng/mL/cm³ was comparable with that of patients in the high-risk group (P=0.463).

Conclusion

PSAD and primary Gleason pattern are potential risk factors associated with biochemical failure in intermediate-risk PCa patients after radical prostatectomy. Regarding significant differences in prognosis according to PSAD as well as primary Gleason pattern on biopsy, a subset of the intermediate-risk patients could be identified with outcomes that were equivalent to that of high-risk patients.

Outcomes and prognostic factors in intermediate-risk prostate cancer: multi-institutional analysis of the Spanish RECAP database

PURPOSE

To retrospectively assess outcomes and to identify prognostic factors in patients diagnosed with intermediate-risk (IR) prostate cancer (PCa) treated with primary external beam radiotherapy (EBRT).

MATERIALS AND METHODS

Data were obtained from the multi-institutional Spanish RECAP database, a population-based prostate cancer registry in Spain. All IR patients (NCCN criteria) who underwent primary EBRT were included. The following variables were assessed: age; prostate-specific antigen (PSA); Gleason score; clinical T stage; percentage of positive biopsy cores (PPBC); androgen deprivation therapy (ADT); and radiotherapy dose. The patients were stratified into one of three risk subcategories: (1) favourable IR (FIR; GS 6, ≤ T2b or GS 3 + 4, ≤ T1c), (2) marginal IR (MIR; GS 3 + 4, T2a-b), and (3) unfavourable IR (UIR; GS 4 + 3 or T2c). Biochemical relapse-free survival (BRFS), disease-free survival (DFS), cancer-specific survival (CSS), and overall survival (OS) were assessed.

RESULTS

A total of 1754 patients from the RECAP database were included and stratified by risk group: FIR, n = 781 (44.5%); MIR, n = 252 (14.4%); and UIR, n = 721 (41.1%). Mean age was 71 years (range 47-86). Mean PSA was 10.4 ng/ml (range 6-20). The median radiotherapy dose was 74 Gy, with mean doses of 72.5 Gy (FIR), 73.4 Gy (MIR), and 72.8 Gy (UIR). Most patients (88%) received ADT for a median of 7.1 months. By risk group (FIR, MIR, UIR), ADT rates were, respectively, 88.9, 86.5, and 86.9%. Only patients with ≥ 24 months of follow-up post-EBRT were included in the survival analysis (n = 1294). At a median follow-up of 52 months (range 24-173), respective 5- and 10-year outcomes were: OS 93.6% and 79%; BRFS 88.9% and 71.4%; DFS 96.1% and 89%; CSS 98.9% and 94.6%. Complication rates (≥ grade 3) were: acute genitourinary (GU) 2%; late GU 1%; acute gastrointestinal (GI) 2%; late GI 1%. There was no significant association between risk group and BRFS or OS. However, patients with favourable-risk disease had significantly better 5- and 10-year DFS than patients with UIR: 98.7% vs. 92.4% and 92% vs. 85.8% (p = 0.0005). CSS was significantly higher (p = 0.0057) in the FIR group at 5 (99.7% vs. 97.3%) and 10 years (96.1% vs. 93.4%). On the multivariate analyses, the following were significant predictors of survival: ADT (BRFS and DFS); dose ≥ 74 Gy (BRFS); age (OS).

CONCLUSIONS

This is the first nationwide study in Spain to report long-term outcomes of patients with intermediate-risk PCa treated with EBRT. Survival outcomes were good, with a low incidence of both acute and late toxicity. Patients with unfavourable risk characteristics had significantly lower 5- and 10-year disease-free survival rates. ADT and radiotherapy dose ≥ 74 Gy were both significant predictors of treatment outcomes.

The Prognostic PDE4D7 Score in a Diagnostic Biopsy Prostate Cancer Patient Cohort with Longitudinal Biological Outcomes

Purpose. To further validate the prognostic power of the biomarker PDE4D7, we investigated the correlation of PDE4D7 scores adjusted for presurgical clinical variables with longitudinal postsurgical biological outcomes. Methods. RNA was extracted from biopsy punches of resected tumors (550 patients; RP cohort) and diagnostic needle biopsies (168 patients; DB cohort). Cox regression and survival were applied to correlate PDE4D7 scores with patient outcomes. Logistic regression was used to combine the clinical CAPRA score with PDE4D7. Results. In univariate analysis, the PDE4D7 score was significantly associated with PSA recurrence after prostatectomy in both studied patient cohorts' analysis (HR 0.53; 95% CI 0.41-0.67; p<1.0E-04 and HR 0.47; 95% CI 0.33-0.65; p<1.0E-04, respectively). After adjustment for the presurgical clinical variables preoperative PSA, PSA density, biopsy Gleason, clinical stage, percentage tumor in the biopsy (data only available for RP cohort), and percentage of positive biopsies, the HR was 0.49 (95% CI 0.38-0.64; p<1.0E-04) and 0.43 (95% CI 0.29-0.63; p<1.0E-04), respectively. The addition of the PDE4D7 to the clinical CAPRA score increased the AUC by 5% over the CAPRA score alone (0.82 versus 0.77; p=0.004). This combination model stratified 14.6% patients of the DB cohort to no risk of biochemical relapse (NPV 100%) over a follow-up period of up to 15 years. Conclusions. The PDE4D7 score provides independent risk information for pretreatment risk stratification. Combining CAPRA with PDE4D7 scores significantly improved the clinical risk stratification before surgery.

The Within-Group Discrimination Ability of the Cancer of the Prostate Risk Assessment Score for Men with Intermediate-Risk Prostate Cancer

BACKGROUND

Significant clinical heterogeneity within contemporary risk group is well known, particularly for those with intermediate-risk prostate cancer (IRPCa). Our study aimed to analyze the ability of the Cancer of the Prostate Risk Assessment (CAPRA) score to discern between favorable and non-favorable risk in patients with IRPCa.

METHODS

We retrospectively reviewed the data of 203 IRPCa patients who underwent extraperitoneal robot-assisted radical prostatectomy (RARP) performed by a single surgeon. Pathologic favorable IRPCa was defined as a Gleason score ≤ 6 and organ-confined stage at surgical pathology. The CAPRA score was compared with two established criteria for the within-group discrimination ability.

RESULTS

Overall, 38 patients (18.7% of the IRPCa cohort) had favorable pathologic features after RARP. The CAPRA score significantly correlated with established criteria I and II and was inversely associated with favorable pathology (all P < 0.001). The area under the receiver operating characteristic curve for the discriminative ability between favorable and non-favorable pathology was 0.679 for the CAPRA score and 0.610 and 0.661 for established criteria I and II, respectively. During a median 37.8 (interquartile range, 24.6-60.2) months of follow-up, 66 patients (32.5%) experienced biochemical recurrence (BCR). Cox regression analysis revealed that the CAPRA score, as a continuous sum score model or 3-group risk model, was an independent predictor of BCR after RARP.

CONCLUSION

The within-group discrimination ability of preoperative CAPRA score might help in patient counseling and selecting optimal treatments for those with IRPCa.

Variability in Outcomes for Patients with Intermediate-risk Prostate Cancer (Gleason Score 7, International Society of Urological Pathology Gleason Group 2-3) and Implications for Risk Stratification: A Systematic Review

CONTEXT

Optimal management for patients with intermediate-risk (IR) prostate cancer (PCa) remains controversial. Clinical metrics provide guidance on appropriate management options.

OBJECTIVE

To report estimates for clinically relevant outcomes in men with IR PCa based on clinical and pathological features.

EVIDENCE ACQUISITION

PubMed and programs from key 2015 uro-oncology congresses were searched using the terms "intermediate", "Gleason 3 + 4", "Gleason 4 + 3", "active surveillance", "treatment", "adverse pathology", AND "prostate cancer." Articles meeting prespecified criteria were retrieved. Bibliographies were scanned for additional relevant references.

EVIDENCE SYNTHESIS

Men with IR PCa have a wide range of predicted clinically relevant outcomes. Within the IR category, estimate ranges for adverse surgical pathology and 5-yr disease progression are 15-64% and 21-91%, respectively. Clinical parameters and predictive nomograms refine these estimates, but do not uniformly differentiate favorable and unfavorable IR PCa. Variations in study design and data quality in source manuscripts mandate caution in interpreting results.

CONCLUSIONS

Outcomes in IR PCa are heterogeneous. Refinements in personalized risk assessment are needed to better select IR PCa patients for surveillance.

PATIENT SUMMARY

Current and future risk stratification tools may provide additional information to identify men with intermediate-risk prostate cancer who may consider active surveillance.

External validation of a nomogram for identification of pathologically favorable disease in intermediate risk prostate cancer patients

OBJECTIVE

To establish an external validation of the new nomogram from Gandaglia et al which provides estimates of the probability of pathological favorable disease in pre-operatively defined intermediate-risk PCa.

PATIENTS AND METHODS

Overall, 2928 intermediate-risk PCa patients according to the D'Amico classification undergoing RP and bilateral lymph node dissection in seven academic centres between 2000 and 2011. Pathologically favorable PCa was defined as low-grade organ-confined disease. The Receiver Operating Characteristic (ROC) curve was obtained to quantify the overall accuracy (Area Under the Curve, AUC) of the model to predict specimen-confined (SC) disease. Calibration curve was then constructed to illustrate the relationship between the risk-estimates obtained by the model and the observed proportion of SC disease. Kaplan-Meier method was used for PSA recurrence-free survival (PSA-RFS) assessment.

RESULTS

Median age was 68 years. 10.6% patients finally presented pathologically favorable disease characteristics at RP. A higher PSAD (OR = 0.01; 95%CI = 0.00-0.04; P < 0.0001) and percentage of positive cores (OR = 0.97; 95%CI = 0.96-0.98; P < 0.0001) were associated with a reduced probability of favorable disease at RP in multivariate analysis. ROC curve analysis showed strongest accuracy of the model (AUC = 0.82; 95%CI = 0.79-0.84). Favorable PCa had a significantly better PSA recurrence-free survival rates as compared to unfavorable PCa after RP (94.2% vs 74.4% at 4 years, P < 0.0001).

CONCLUSIONS

This external validation of the Gandaglia nomogram shows relevant accuracy with one out of ten patients in this intermediate risk PCa group with pathologically proven organ-confined disease. This validated risk calculator can help physician to distinguish favorable intermediate risk PCa that can be treated by conservative approach or safer nerve-sparing surgery.

Human Prostate Tissue-derived Extracellular Matrix as a Model of Prostate Microenvironment

BACKGROUND

Clinical experience highlights the wide heterogeneity of primary prostate cancer (PPCa), even when potentially related to the same grade and stage. Currently available prediction tools and biomarkers do not always allow for early recognition of PPCa aggressive phenotype, sometimes making it impossible to distinguish among men harbouring indolent tumours or life-threatening disease.

OBJECTIVE

To establish a novel ex vivo/in vitro model suitable to estimate the invasive phenotype of PPCa cells (PPCaC).

DESIGN, SETTING, AND PARTICIPANTS

The ability of PPCaC to infiltrate the prostate extracellular matrix (ECM) was used as an index of invasion. ECM was obtained by decellularising 24 NT-prostate specimens from radical prostatectomy. PPCaC were obtained from six tumours with different Gleason patterns and pathological stages. Invasion ability was estimated in direct-cocolture experiments.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

The extent of ECM invasion by PPCaC was quantified by counting the number of infiltrated cells. Mann-Whitney test was utilised for statistical comparisons.

RESULTS AND LIMITATIONS

Samples of ECM resulted to be free of cells and DNA and with a preserved three-dimensional structure and stromal protein content. The system resulted to be reliable since well characterised normal-, benign-, and malignant-prostate cell lines either re-epitheliased or invaded the matrices, according to their specific nature. Similarly, PPCaC invaded the ECMs consistently with their stage and biochemical recurrence. Of notice, this model was able to identify a different invasive phenotype even among tumours with equal Gleason patterns and pathological stages. The small sample size represents a limitation.

CONCLUSIONS

We developed an ex vivo/in vitro model able to reproduce the original PPCa-microenvironment and suitable to recognise the inherent invasive behaviour of PPCaC.

PATIENT SUMMARY

We developed a novel ex vivo/in vitro system which enables us to uncover which prostate tumours host potentially aggressive cancer cells. The identification of cancer cells with different invasive abilities will likely lead to the identification of new biomarkers to safely predict disease progression.

[Localized intermediate- to high-risk prostate cancer]

BACKGROUND

National and international guidelines recommend radical prostatectomy (RP) and radiotherapy (EBRT) as standard treatment for intermediate- and high-risk prostate cancer. Survival benefit of RP in prostate cancer has been proven in prospectively randomized trials. In contrast, the benefit of EBRT as well as the direct comparison of EBRT and RP have been investigated in several retrospective analyses, but are limited by typical problems associated with retrospective studies.

RESULTS

Most of the studies comparing RP with EBRT favor RP with regard to overall survival and cancer-specific survival. Especially in young patients with high-grade prostate cancer, RP seems to be superior in comparison with EBRT. These patient are at high risk of a PSA recurrence and subsequently need an additional radiotherapy. Mortality and morbidity related to these both methods are low. Main complications of RP are urinary incontinence and erectile dysfunction. In contrast, rectal sequelae, erectile dysfunction, and irritative urinary symptoms are the main cause for postinterventional morbidity in patients after EBRT.

Stratification of brachytherapy-treated intermediate-risk prostate cancer patients into favorable and unfavorable cohorts

Purpose

To evaluate biochemical failure (BF) and prostate cancer specific mortality (PCSM) in intermediate-risk (IR) brachytherapy patients stratified into favorable and unfavorable cohorts, and to compare those outcomes to patients with low (LR) and high-risk (HR) disease.

Material and methods

From March 1995 till February 2012, 2,502 consecutive patients underwent permanent interstitial brachytherapy for clinically localized prostate cancer. Patients were stratified into risk groups as per the NCCN guidelines with further stratification of the intermediate risk cohort into unfavorable (primary Gleason pattern 4, ≥ 50% positive biopsies or ≥ 2 IR features) and favorable cohorts. Median follow-up was 8.5 years. The brachytherapy prescription dose was prescribed to the prostate gland with generous periprostatic margins. Biochemical failure was defined as a PSA > 0.40 ng/ml after nadir. Patients with metastatic prostate cancer or non-metastatic castrate resistant disease who died of any cause were classified as dead of prostate cancer. Multiple parameters were evaluated for effect on outcomes.

Results

Fifteen year BF for LR, favorable IR, unfavorable IR, and HR were 1.4%, 2.2%, 7.1%, and 11.1% (p < 0.001), respectively. At 15 years, PCSM for LR, favorable IR, unfavorable IR, and HR was 0.3%, 0.6%, 2.2% and 4.6% (p < 0.001), respectively. In multivariate analysis, BF was best predicted by risk group, pre-implant PSA, percent positive biopsies, prostate volume, and ADT duration, while PCSM was most closely related to risk group, percent positive biopsies and prostate volume.

Conclusions

Patients with favorable IR disease have biochemical and PCSM outcomes comparable to those of patients with LR disease. Although unfavorable IR has greater than a 3-fold increased risk of BF and PCSM when compared to favorable IR, the outcomes remain superior to those men with HR disease.

Is supplemental external beam radiation therapy essential to maximize brachytherapy outcomes in patients with unfavorable intermediate-risk disease?

PURPOSE

To evaluate whether supplemental external beam radiotherapy (EBRT) is essential to maximize Pd-103 brachytherapy outcomes in patients with unfavorable intermediate-risk (IR) disease.

METHODS AND MATERIALS

A total of 630 patients were assessed from two prospective randomized brachytherapy trials evaluating the role of supplemental EBRT in patients with higher risk features. Patients were stratified into unfavorable IR (primary Gleason pattern 4, ≥50% positive biopsies, or ≥2 IR features), favorable IR, and high-risk (HR) cohorts. Median follow-up was 7.5 years. The brachytherapy prescription dose was prescribed to the prostate gland with generous periprostatic margins. Biochemical failure (BF) was defined as a prostate-specific antigen >0.40 ng/mL after nadir. Patients with metastatic prostate cancer or nonmetastatic castrate-resistant disease who died of any cause were classified as dead of prostate cancer. Multiple parameters were evaluated for effect on outcomes.

RESULTS

The 10-year BF for favorable IR, unfavorable IR, and HR was 1.7%, 6.6%, and 15.5% (p < 0.001). At 10 years, prostate cancer-specific mortality (PCSM) and overall mortality (OM) were 0% and 20.4%, 2.1% and 23.2%, and 4.3% and 42.4% for favorable IR, unfavorable IR, and HR. Although unfavorable IR patients had a greater incidence of BF, PCSM, and OM when compared with favorable IR, neither the addition nor dose of supplemental EBRT influenced outcome.

CONCLUSIONS

Outcomes for favorable IR were superior to those with unfavorable IR. Within the confines of this study, neither the addition nor dose of supplemental EBRT influenced BF, PCSM, or OM in patients with IR disease.

MiR-182 Is Associated with Growth, Migration and Invasion in Prostate Cancer via Suppression of FOXO1

BACKGROUND

MicroRNA (miRNA) have been shown to regulate gene expression in many cancers. MiR-182 has recently been found to be prognostic for patients treated with radical prostatectomy for prostate cancer. We sought to assess miR-182 as a prognostic marker and understand its role in prostate cancer progression and metastasis.

METHODS

We analysed miR-182 expression among 147 men treated for prostate cancer using biochemical recurrence and metastasis as the endpoints. We examined miR-182 expression in prostate cancer cells and created cell lines that overexpressed miR-182 for functional assays. Finally, we examined pathways through which miR-182 may function using prediction algorithms and confirmed by Western blotting and knock-down assays.

RESULTS

We found that miR-182 was not associated with biochemical recurrence (p=0.1111) or metastasis (p=0.9268) following radical prostatectomy. However, in mechanistic assays, we found that miR-182 expression was higher among aggressive prostate cancer cells and that ectopic miR-182 expression resulted in increased proliferation, migration and invasion in vitro. We identified FOXO1 as regulated by miR-182 in prostate cancer cells, confirmed that ectopic miR-182 expression resulted in diminished FOXO1 levels, and showed that miR-182 inhibition results in increased FOXO1 levels. Expression of FOXO1 (p=0.0014) in tumors from patients who developed biochemical recurrence compared to tumors from patients who were recurrence-free five years after their radical prostatectomy.

CONCLUSIONS

Our findings suggest that miR-182 may act to increase prostate cancer proliferation, migration and invasion through suppression of FOXO1. This may be valuable in the development of further therapeutic interventions.

Identification and Validation of a Five MicroRNA Signature Predictive of Prostate Cancer Recurrence and Metastasis: A Cohort Study

Background: MicroRNA (miRNA) have been shown to be important in regulating gene expression in prostate cancer. We used next generation miRNA sequencing to conduct a whole miRNome analysis to identify miRNAs associated with prostate cancer metastasis.

Methods: We conducted discovery and validation analyses of miRNAs among a total of 546 men who underwent surgery for prostate cancer using the development of metastasis as an endpoint. Genome wide analysis was conducted among the discovery group (n=31) to identify new miRNAs associated with prostate cancer metastasis. Selected miRNAs were then analyzed using qPCR on prostatectomy specimens from an independent cohort (n=515) to determine whether their expression could predict the development of metastasis after surgery. To examine the biology underlying these associations, we created prostate cancer cell lines which overexpressed miR-301a for in vitro and in vivo functional assays.

Results: We identified 33 miRNAs associated with prostate cancer metastasis and selected a panel comprising miRs-301a, 652, 454, 223 and 139 which strongly predicted metastasis (AUC=95.3%, 95%C.I.:84%-99%). Among the validation cohort, the 15-year metastasis-free survival was 77.5% (95% C.I.:63.9%-86.4%) for patients with a high miRNA panel score and 98.8% (95% C.I.:94.9%-99.7%, p<0.0001 for difference) for those with a low score. After adjusting for grade, stage, and PSA, the hazard ratio for metastasis was 4.3 (95% C.I.: 1.7-11.1, p=0.002) for patients with a high miRNA panel score, compared to those with a low score. Prostate cancer cell lines overexpressing miR-301a had in significantly higher tumor growth and metastasis in a xenograft mouse model.

Conclusions: A panel of miRNAs is associated with prostate cancer metastasis. These could be used as potential new prognostic factors in the surgical management of prostate cancer.

Identification of pathologically favorable disease in intermediate-risk prostate cancer patients: Implications for active surveillance candidates selection

BACKGROUND

Intermediate-risk prostate cancer (PCa) represents a heterogeneous disease, where a non-negligible proportion of patients harbor favorable pathologic characteristics and are potentially eligible for active surveillance (AS). We aimed at developing a model for the identification of pathologically favorable PCa at radical prostatectomy (RP) among intermediate-risk patients.

METHODS

Overall, 3,821 intermediate-risk patients treated with RP at two centers between 2005 and 2013 were identified. Pathologically favorable PCa was defined as low-grade organ-confined disease. Age, biopsy Gleason, PSA density (PSAD), and the percentage of positive cores were included in multivariable logistic regression analyses predicting favorable PCa and formed the basis for a logistic regression-based risk calculator. The internally validated discrimination and calibration of the risk calculator were quantified using 200 bootstrap resamples. Decision curve analysis (DCA) provided an estimate of the net benefit obtained using this model versus treating no one and treating everyone.

RESULTS

Overall, 10.0% of all intermediate risk patients had favorable disease. In multivariable analyses, patients with biopsy Gleason score ≤6 had higher probability of favorable disease compared to those with higher-grade disease (P < 0.001). Similarly, age, PSAD, and percentage of positive cores were associated with the probability of favorable disease (all P ≤ 0.01). The risk calculator achieved a validated accuracy of 82.5%. The DCA showed that our prediction model is better than both treating no one and treating everyone.

CONCLUSIONS

One out of ten intermediate-risk patients harbors favorable disease at RP. Our novel, pre-operative, validated risk calculator may help clinicians identifying patients who could be considered for conservative therapy approaches such as AS.

[Long term biochemical recurrence free survival after radical prostatectomy for cancer: comparative analysis according to surgical approach and clinicopathological stage]

OBJECTIVE

To assess long term biochemical recurrence free survival after radical prostatectomy according to open, laparoscopic and robot-assisted surgical approach and clinicopathological stage.

MATERIAL AND METHODS

A cohort study of 1313 consecutive patients treated by radical prostatectomy for localized or locally advanced prostate cancer between 2000 and 2013. Open surgery (63.7%), laparoscopy (10%) and robot-assisted laparoscopy (26.4%) were performed. Biochemical recurrence was defined by PSA>0,1ng/mL. The biochemical recurrence free survival was described by Kaplan Meier method and prognostic factors were analysed by multivariable Cox regression.

RESULTS

Median follow-up was 57 months (IQR: 31-90). Ten years biochemical recurrence free survival was 88.5%, 71.6% and 53.5% respectively for low, intermediate and high-risk D'Amico groups. On multivariable analysis, the worse prognostic factor was Gleason score (P<0.001). Positive surgical margins rate was 53% in pT3 tumours and 24% in pT2 tumours (P<0.001). Biochemical recurrence free survival (P=0.06) and positive surgical margins rate (P=0.87) were not statistically different between the three surgical approaches.

CONCLUSION

Biochemical recurrence free survival in our study does not differ according to surgical approach and is similar to published series. Ten years biochemical recurrence free survival for high-risk tumours without hormone therapy is 54% justifying the role of surgery in the therapeutic conversations in this group of tumours.

LEVEL OF EVIDENCE

3.