The molecular origin and taxonomy of mucinous ovarian carcinoma.

Mucinous ovarian carcinoma (MOC) is a unique subtype of ovarian cancer with an uncertain etiology, including whether it genuinely arises at the ovary or is metastatic disease from other organs. In addition, the molecular drivers of invasive progression, high-grade and metastatic disease are poorly defined. We perform genetic analysis of MOC across all histological grades, including benign and borderline mucinous ovarian tumors, and compare these to tumors from other potential extra-ovarian sites of origin. Here we show that MOC is distinct from tumors from other sites and supports a progressive model of evolution from borderline precursors to high-grade invasive MOC. Key drivers of progression identified are TP53 mutation and copy number aberrations, including a notable amplicon on 9p13. High copy number aberration burden is associated with worse prognosis in MOC. Our data conclusively demonstrate that MOC arise from benign and borderline precursors at the ovary and are not extra-ovarian metastases.

Preliminary Diagnostic Accuracy of Multiparametric Magnetic Resonance Imaging to Detect Residual Prostate Cancer Following Focal Therapy with Irreversible Electroporation.

BACKGROUND: It is recommended to perform multiparametric magnetic resonance imaging (mpMRI) in the follow-up following focal therapy of prostate cancer (PCa). OBJECTIVE: To determine the diagnostic accuracy of mpMRI to detect residual PCa following focal therapy with irreversible electroporation. DESIGN, SETTING, AND PARTICIPANTS: Seventy-six patients with biopsy-proven localized PCa consented for primary irreversible electroporation between February 2013 and March 2016. Final analysis was performed on 50 patients that received follow-up mpMRI at 6 mo, serial prostate-specific antigen (PSA) testing, and transperineal template-mapping biopsies at 12 mo. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: Outfield regions of interest (ROI) were reported using PI-RADS version 2. A binary outcome (suspicious vs nonsuspicious) was given for the infield ablation zone. Sensitivity, specificity, positive predictive values, and negative predictive values were calculated for different definitions of significant PCa: (1) Gleason ≥4+3 or Gleason ≥3+3 with a maximum cancer core length ≥6mm, (2) Gleason ≥3+4 or Gleason ≥3+3 with a maximum cancer core length ≥4mm, for outfield and infield ROI. Multivariate linear regression analyses evaluated the additional value of nadir PSA. RESULTS AND LIMITATIONS: Sensitivity, specificity, positive predictive values, and negative predictive values of infield ROI was 43%, 86%, 33%, and 90% for definition 1 and 38%, 86%, 33%, and 88% for definition 2, respectively. For outfield ROI this was 33%, 82%, 20%, and 90% for definition 1 and 38%, 86%, 50%, and 80% for definition 2. PSA had no additional value in predicting residual significant PCa. Limitations include retrospective design, single reader, and low incidence of residual PCa. CONCLUSIONS: Our preliminary data suggest that mpMRI can rule out high-volume residual PCa. However, follow-up biopsies should still be performed to determine oncological control. PATIENT SUMMARY: Multiparametric magnetic resonance imaging is able to detect high-volume significant prostate cancer following focal therapy. Prostate biopsies are still required in the follow-up of focal therapy as (low-volume) significant prostate cancer is being missed by multiparametric magnetic resonance imaging.

An analysis of a multiple biomarker panel to better predict prostate cancer metastasis after radical prostatectomy.

A plethora of individual candidate biomarkers for predicting biochemical relapse in localized prostate cancer (PCa) have been proposed. Combined biomarkers may improve prognostication, and ensuring validation against more clinically relevant endpoints are required. The Australian PCa Research Centre NSW has contributed to numerous studies of molecular biomarkers associated with biochemical relapse. In the current study, these biomarkers were re-analyzed for biochemical relapse, metastatic relapse and PCa death with extended follow-up. Biomarkers of significance were then used to develop a combined prognostic model for clinical outcomes and validated in a large independent cohort. The discovery cohort (n = 324) was based on 12 biomarkers with a median follow-up of 16 years. Seven biomarkers were significantly associated with biochemical relapse. Three biomarkers were associated with metastases: AZGP1, Ki67 and PML. Only AZGP1 was associated with PCa death. In their individual and combinational forms, AZGP1 and Ki67 as a dual BM signature was the most robust predictor of metastatic relapse (AUC 0.762). The AZPG1 and Ki67 signature was validated in an independent cohort of 347 PCa patients. The dual BM signature of AZGP1 and Ki67 predicted metastasis in the univariable (HR 7.2, 95% CI, 1.6-32; p = 0.01) and multivariable analysis (HR 5.4, 95% CI, 1.2-25; p = 0.03). The dual biomarker signature marginally improved risk prediction compared to AZGP1 alone (AUC 0.758 versus 0.738, p < 0.001). Our findings indicate that biochemical relapse is not an adequate surrogate for metastasis or PCa death. The dual biomarker signature of AZGP1 and Ki67 offers a small benefit in predicting metastasis over AZGP1 alone.

Prostate cancer in 432 men aged <50 years in the prostate-specific antigen era: a new outlook.

OBJECTIVE: To evaluate the clinical presentation and treatment outcomes of prostate cancer (PCa) in 432 consecutive patients aged < 50 years in the prostate-specific antigen (PSA) era. METHODS: Retrospective analysis was performed on all patients with PCa (14 570) from the years 1994 to 2017. A total of 432 consecutive patients aged < 50 years were identified. The patients were stratified by D'Amico risk groups, and their clinical presentation and treatment outcomes were analysed. The rates of biochemical recurrence after surgery were compared with the D'Amico prediction model as well as with older propensity-score-matched patients. The surgical pathology results in patients undergoing active surveillance (AS) were compared with those of low-risk patients who underwent immediate surgery. RESULTS: A total of 44%, 42% and 13% of patients harboured low-risk, intermediate-risk and high-risk PCa, respectively. Their median age was 47 years and a positive family history of PCa was reported in 39.1%. Clinical stage was T1 in 65.5% and T2 in 30.0% of patients, and 2.0% of patients had metastatic disease at presentation. Radical prostatectomy (RP) was performed in 78.4% of patients (n = 339) and the biochemical recurrence rates were 7.8% (low-risk), 15.3% (intermediate-risk) and 23.3% (high-risk) at 5 years post-surgery. These rates were lower than expected according to the D'Amico prediction model or when compared with older matched patients. A total of 74 patients with low-risk PCa underwent AS and only 17.6% (n = 13) required radical treatment after a median follow-up of 46 months. The surgical pathology results in patients undergoing ASdid not differ significantly from patients with low-risk PCa who underwent immediate surgery (positive surgical margins [P = 0.145], tumour volume [P = 0.257] or seminal vesicle involvement [P = 0.100]). Of the present cohort, only 0.4% died from PCa during a median follow-up of 65 months. CONCLUSIONS: The clinical presentation and prognosis of young patients has changed dramatically during the PSA era. Patients nowadays present with lower-risk disease that can be treated adequately, with reassuring biochemical recurrence rates at 5 years post-surgery. AS appears to be safe in patients with low-risk. PCa.

Impact on genitourinary function and quality of life following focal irreversible electroporation of different prostate segments.

PURPOSE: We aimed to evaluate the genitourinary function and quality of life (QoL) following the ablation of different prostate segments with irreversible electroporation (IRE) for localized prostate cancer (PCa). METHODS: Sixty patients who received primary focal IRE for organ-confined PCa were recruited for this study. Patients were evaluated for genitourinary function and QoL per prostate segment treated (anterior vs. posterior, apex vs. base vs. apex-to-base, unilateral vs. bilateral). IRE system settings and patient characteristics were compared between patients with preserved vs. those with impaired erectile function and urinary continence. Data were prospectively collected at baseline, 3, 6, and 12 months using the expanded prostate cancer index composite, American Urological Association symptom score, SF-12 physical and mental component summary surveys. Difference over time within segments per questionnaire was evaluated using the Wilcoxon's signed rank test. Outcome differences between segments were assessed using covariance models. Baseline measurements included questionnaire scores, age, and prostate volume. RESULTS: There were no statistically significant changes over time for overall urinary (P = 0.07-0.89), bowel (P = 0.06-0.79), physical (P = 0.18-0.71) and mental (P = 0.45-0.94) QoL scores within each segment. Deterioration of sexual function scores was observed at 6 months within each segment (P = 0.001-0.16). There were no statistically significant differences in QoL scores between prostate segments (P = 0.08-0.97). Older patients or those with poor baseline sexual function at time of treatment were associated with a greater risk of developing erectile dysfunction. CONCLUSION: IRE is a feasible modality for all prostate segments without any significantly different effect on the QoL outcomes. Older patients and those with poor sexual function need to be counseled regarding the risk of erectile dysfunction.

Identifying the morphologic basis for radiomic features in distinguishing different Gleason grades of prostate cancer on MRI: Preliminary findings.

Translation of radiomics into the clinic may require a more comprehensive understanding of the underlying morphologic tissue characteristics they reflect. In the context of prostate cancer (PCa), some studies have correlated gross histological measurements of gland lumen, epithelium, and nuclei with disease appearance on MRI. Quantitative histomorphometry (QH), like radiomics for radiologic images, is the computer based extraction of features for describing tumor morphology on digitized tissue images. In this work, we attempt to establish the histomorphometric basis for radiomic features for prostate cancer by (1) identifying the radiomic features from T2w MRI most discriminating of low vs. intermediate/high Gleason score, (2) identifying QH features correlated with the most discriminating radiomic features previously identified, and (3) evaluating the discriminative ability of QH features found to be correlated with spatially co-localized radiomic features. On a cohort of 36 patients (23 for training, 13 for validation), Gabor texture features were identified as being most predictive of Gleason grade on MRI (AUC of 0.69) and gland lumen shape features were identified as the most predictive QH features (AUC = 0.75). Our results suggest that the PCa grade discriminability of Gabor features is a consequence of variations in gland shape and morphology at the tissue level.

Pair-matched patient-reported quality of life and early oncological control following focal irreversible electroporation versus robot-assisted radical prostatectomy.

PURPOSE: The design, conduct and completion of randomized trials for curative prostate cancer (PCa) treatments are challenging. To evaluate the effect of robot-assisted radical prostatectomy (RARP) versus focal irreversible electroporation (IRE) on patient-reported quality of life (QoL) and early oncological control using propensity-scored matching. METHODS: Patients with T1c-cT2b significant PCa (high-volume ISUP 1 or any 2/3) who received unifocal IRE were pair-matched to patients who received nerve-sparing RARP. Patient-reported outcomes were prospectively assessed using the Expanded Prostate Cancer Index Composite (EPIC), AUA symptom score and Short Form of Health Survey (SF-12) physical and mental components. Oncological failure was defined as biochemical recurrence (RARP) or positive follow-up biopsies (IRE). Generalized mixed-effect models were used to compare IRE and RARP. RESULTS: 50 IRE patients were matched to 50 RARP patients by propensity score. IRE was significantly superior to RARP in preserving pad-free continence (UC) and erections sufficient for intercourse (ESI). The absolute differences were 44, 21, 13, 14% for UC and 32, 46, 27, 22% for ESI at 1.5, 3, 6, and 12 months, respectively. The EPIC summary scores showed no statistically significant differences. Urinary symptoms were reduced for IRE and RARP patients at 12 months, although IRE patient initially had more complaints. IRE patients experienced more early oncological failure than RARP patients. CONCLUSIONS: These data demonstrated the superior preservation of UC and ESI with IRE compared to RARP up to 12 months after treatment. Long-term oncological data are warranted to provide ultimate proof for or against focal therapy.

Radiomic features on MRI enable risk categorization of prostate cancer patients on active surveillance: Preliminary findings.

BACKGROUND: Radiomic analysis is defined as computationally extracting features from radiographic images for quantitatively characterizing disease patterns. There has been recent interest in examining the use of MRI for identifying prostate cancer (PCa) aggressiveness in patients on active surveillance (AS). PURPOSE: To evaluate the performance of MRI-based radiomic features in identifying the presence or absence of clinically significant PCa in AS patients. STUDY TYPE: Retrospective. SUBJECTS MODEL: MRI/TRUS (transperineal grid ultrasound) fusion-guided biopsy was performed for 56 PCa patients on AS who had undergone prebiopsy. FIELD STRENGTH/SEQUENCE: 3T, T2 -weighted (T2 w) and diffusion-weighted (DW) MRI. ASSESSMENT: A pathologist histopathologically defined the presence of clinically significant disease. A radiologist manually delineated lesions on T2 w-MRs. Then three radiologists assessed MRIs using PIRADS v2.0 guidelines. Tumors were categorized into four groups: MRI-negative-biopsy-negative (Group 1, N = 15), MRI-positive-biopsy-positive (Group 2, N = 16), MRI-negative-biopsy-positive (Group 3, N = 10), and MRI-positive-biopsy-negative (Group 4, N = 15). In all, 308 radiomic features (First-order statistics, Gabor, Laws Energy, and Haralick) were extracted from within the annotated lesions on T2 w images and apparent diffusion coefficient (ADC) maps. The top 10 features associated with clinically significant tumors were identified using minimum-redundancy-maximum-relevance and used to construct three machine-learning models that were independently evaluated for their ability to identify the presence and absence of clinically significant disease. STATISTICAL TESTS: Wilcoxon rank-sum tests with P < 0.05 considered statistically significant. RESULTS: Seven T2 w-based (First-order Statistics, Haralick, Laws, and Gabor) and three ADC-based radiomic features (Laws, Gradient and Sobel) exhibited statistically significant differences (P < 0.001) between malignant and normal regions in the training groups. The three constructed models yielded overall accuracy improvement of 33, 60, 80% and 30, 40, 60% for patients in testing groups, when compared to PIRADS v2.0 alone. DATA CONCLUSION: Radiomic features could help in identifying the presence and absence of clinically significant disease in AS patients when PIRADS v2.0 assessment on MRI contradicted pathology findings of MRI-TRUS prostate biopsies. LEVEL OF EVIDENCE: 3 Technical Efficacy: Stage 2 J. Magn. Reson. Imaging 2018.

Focal irreversible electroporation as primary treatment for localized prostate cancer.

OBJECTIVES: To determine the safety, quality of life (QoL) and short-term oncological outcomes of primary focal irreversible electroporation (IRE) for the treatment of localized prostate cancer (PCa), and to identify potential risk factors for oncological failure. PATIENTS AND METHODS: Patients who met the consensus guidelines on patient criteria and selection methods for primary focal therapy were eligible for analysis. Focal IRE was performed for organ-confined clinically significant PCa, defined as high-volume disease with Gleason sum score 6 (International Society of Urological Pathology [ISUP] grade 1) or any Gleason sum score of 7 (ISUP grades 2-3). Oncological, adverse event (AE) and QoL outcome data, with a minimum of 6 months' follow-up, were analysed. Patient characteristics and peri-operative treatment variables were compared between patients with and without oncological failure on follow-up biopsy. Wilcoxon's signed rank test, Wilcoxon's rank sum test and the chi-squared test were used to assess statistically significant differences in paired continuous, unpaired continuous and categorical variables respectively. RESULTS: A total of 63 patients met all eligibility criteria and were included in the final analysis. No high-grade AEs occurred. QoL questionnaire analysis demonstrated no significant change from baseline in physical (P = 0.81), mental (P = 0.48), bowel (P = 0.25) or urinary QoL domains (P = 0.41 and P = 0.25), but there was a mild decrease in the sexual QoL domain (median score 66 at baseline vs 54 at 6 months; P < 0.001). Compared with baseline, a decline of 70% in prostate-specific antigen level (1.8 ng/mL, interquartile range 0.96-4.8 ng/mL) was seen at 6-12 months. A narrow safety margin (P = 0.047) and system errors (P = 0.010) were identified as potential early risk factors for in-field oncological failure. In-field and whole-gland oncological control on follow-up biopsies was 84% (38/45 patients) and 76% (34/45 patients); this increased to 97% (38/39 patients) and 87% (34/39 patients) when patients treated with a narrow safety margin and system errors were excluded. CONCLUSION: Our data support the safety and feasibility of focal IRE as a primary treatment for localized PCa with effective short-term oncological control in carefully selected men.

Superior Biochemical Recurrence and Long-term Quality-of-life Outcomes Are Achievable with Robotic Radical Prostatectomy After a Long Learning Curve-Updated Analysis of a Prospective Single-surgeon Cohort of 2206 Consecutive Cases.

BACKGROUND: Our earlier analysis suggested that robot-assisted radical prostatectomy (RARP) achieved superiority over open radical prostatectomy (ORP) in terms of positive surgical margin (PSM) rates and functional outcomes. OBJECTIVE: With larger sample size and longer follow-up, the objective of this study update is to assess whether our previous findings are upheld and whether the improved PSM rates for RARP after an initial learning curve compared with ORP-as observed in our earlier analysis-ultimately resulted in improved biochemical control. DESIGN, SETTING, AND PARTICIPANTS: Prospective observational study comparing two surgical techniques; 2271 consecutive men underwent RARP (1520) or ORP (751) at a single centre from 2006 to 2016. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: Demographic and clinicopathological data were prospectively collected. The EPIC-QOL questionnaire was administered at baseline and 1.5, 3, 6, 12, and 24 mo. Multivariate linear regression modelled the difference in quality of life (QOL) domains against case number; logistic and Cox regression modelled the differences in PSM and biochemical recurrence (BCR) hazard ratios (HR), respectively. RESULTS AND LIMITATIONS: A total of 2206 men were included in BCR/PSM analysis and 1045 consented for QOL analysis. Superior pT2 surgical margins, early and late sexual outcomes, and early urinary outcomes were upheld and became more robust (narrowing of 95% confidence intervals [CIs]). The risk of BCR was initially higher for RARP, improved after 191 RARPs, and was 35% lower (hazard ratio [HR] 0.65, 95% CI 0.47-0.90) at final RARP, plateauing after 226 RARPs. Improved late (12-24 mo) urinary bother scores (adjusted mean difference [AMD]=4.7, 95% CI 1.3-8.0) and irritative-obstructive scores (AMD=3.8, 95% CI 0.9-5.6) at final RARP were demonstrated. Limitations include observational single surgeon data, possible residual confounding, and short follow-up. CONCLUSIONS: The results from this updated analysis demonstrate that RARP can be beneficial for patients of high-volume surgeons, although more randomised studies and studies with survival outcomes are needed. PATIENT SUMMARY: Robot-assisted radical prostatectomy was able to improve functional and oncological outcomes in this single surgeon's learning curve.

Feasibility and safety of focal irreversible electroporation as salvage treatment for localized radio-recurrent prostate cancer.

OBJECTIVES: To evaluate the feasibility, safety, early quality-of-life (QoL) and oncological outcomes of salvage focal irreversible electroporation (IRE) for radio-recurrent prostate cancer (PCa). PATIENTS AND METHODS: Patients with localized, radio-recurrent PCa without evidence of metastatic or nodal disease were offered focal IRE according to the consensus guidelines. Patients with a minimum follow-up of 6 months were eligible for analysis. Adverse events were monitored using the National Cancer Institute Common Terminology Criteria for Adverse Events (CTCAE version 4.0). Patient-reported QoL data were collected at baseline, 6 weeks, 3, 6 and 12 months using the Expanded Prostate Cancer Index Composite (EPIC), the American Urological Association (AUA) symptom score and the 12-item short-from health survey (SF-12) physical and mental component summary questionnaires. Oncological control was evaluated according to serial prostate-specific antigen (PSA), 6-month multiparametric magnetic resonance imaging (mpMRI) and 12-month prostate biopsy. Wilcoxon's signed rank test was used to assess QoL differences over time in paired continuous variables. RESULTS: A total of 18 patients were included in the analysis. The median follow-up was 21 months. No high-grade adverse events (CTCAE >2) or recto-urethral fistulae occurred. No statistically significant declines were observed in QoL outcomes (n = 11) on the EPIC bowel domain (P = 0.29), AUA symptom score (P = 0.77), or the SF-12 physical (P = 0.17) or SF-12 mental component summary (P = 0.77) questionnaires. At 6 months, patients who had undergone salvage therapy experienced a decline in EPIC sexual domain score (median of 38-24; P = 0.028) and urinary domain (median of 96-92; P = 0.074). Pad-free continence and erections sufficient for intercourse were preserved in 8/11 patients and 2/6 patients at 6 months, respectively. The mpMRI was clear in 11/13 patients, with two single out-field lesions (true-positive and false-positive, respectively). The median (interquartile range) nadir PSA was 0.39 (0.04-0.43) µg/L. Three and four patients experienced biochemical failure using the Phoenix and Stuttgart definitions of biochemical failure, respectively. Eight out of 10 of the patients were clear of any PCa on follow-up biopsy, whereas two patients had significant PCa on follow-up biopsy (International Society of Urological Pathology grade 5). CONCLUSION: Our short-term safety, QoL and oncological control data show that focal IRE is a feasible salvage option for localized radio-recurrent PCa. A prospective multicentre study (FIRE trial) has been initiated that will provide further insight into the ability of focal IRE to obtain oncological control of radio-recurrent PCa with acceptable patient morbidity.

Computational imaging reveals shape differences between normal and malignant prostates on MRI.

We seek to characterize differences in the shape of the prostate and the central gland (combined central and transitional zones) between men with biopsy confirmed prostate cancer and men who were identified as not having prostate cancer either on account of a negative biopsy or had pelvic imaging done for a non-prostate malignancy. T2w MRI from 70 men were acquired at three institutions. The cancer positive group (PCa+) comprised 35 biopsy positive (Bx+) subjects from three institutions (Gleason scores: 6-9, Stage: T1-T3). The negative group (PCa-) combined 24 biopsy negative (Bx-) from two institutions and 11 subjects diagnosed with rectal cancer but with no clinical or MRI indications of prostate cancer (Cl-). The boundaries of the prostate and central gland were delineated on T2w MRI by two expert raters and were used to construct statistical shape atlases for the PCa+, Bx- and Cl- prostates. An atlas comparison was performed via per-voxel statistical tests to localize shape differences (significance assessed at p < 0.05). The atlas comparison revealed central gland hypertrophy in the Bx- subpopulation, resulting in significant volume and posterior side shape differences relative to PCa+ group. Significant differences in the corresponding prostate shapes were noted at the apex when comparing the Cl- and PCa+ prostates.

A multiparametric magnetic resonance imaging-based risk model to determine the risk of significant prostate cancer prior to biopsy.

OBJECTIVE: To develop and externally validate a predictive model for detection of significant prostate cancer. PATIENTS AND METHODS: Development of the model was based on a prospective cohort including 393 men who underwent multiparametric magnetic resonance imaging (mpMRI) before biopsy. External validity of the model was then examined retrospectively in 198 men from a separate institution whom underwent mpMRI followed by biopsy for abnormal prostate-specific antigen (PSA) level or digital rectal examination (DRE). A model was developed with age, PSA level, DRE, prostate volume, previous biopsy, and Prostate Imaging Reporting and Data System (PIRADS) score, as predictors for significant prostate cancer (Gleason 7 with >5% grade 4, ≥20% cores positive or ≥7 mm of cancer in any core). Probability was studied via logistic regression. Discriminatory performance was quantified by concordance statistics and internally validated with bootstrap resampling. RESULTS: In all, 393 men had complete data and 149 (37.9%) had significant prostate cancer. While the variable model had good accuracy in predicting significant prostate cancer, area under the curve (AUC) of 0.80, the advanced model (incorporating mpMRI) had a significantly higher AUC of 0.88 (P < 0.001). The model was well calibrated in internal and external validation. Decision analysis showed that use of the advanced model in practice would improve biopsy outcome predictions. Clinical application of the model would reduce 28% of biopsies, whilst missing 2.6% significant prostate cancer. CONCLUSIONS: Individualised risk assessment of significant prostate cancer using a predictive model that incorporates mpMRI PIRADS score and clinical data allows a considerable reduction in unnecessary biopsies and reduction of the risk of over-detection of insignificant prostate cancer at the cost of a very small increase in the number of significant cancers missed.

Radiomic features for prostate cancer detection on MRI differ between the transition and peripheral zones: Preliminary findings from a multi-institutional study.

PURPOSE: To evaluate in a multi-institutional study whether radiomic features useful for prostate cancer (PCa) detection from 3 Tesla (T) multi-parametric MRI (mpMRI) in the transition zone (TZ) differ from those in the peripheral zone (PZ). MATERIALS AND METHODS: 3T mpMRI, including T2-weighted (T2w), apparent diffusion coefficient (ADC) maps, and dynamic contrast-enhanced MRI (DCE-MRI), were retrospectively obtained from 80 patients at three institutions. This study was approved by the institutional review board of each participating institution. First-order statistical, co-occurrence, and wavelet features were extracted from T2w MRI and ADC maps, and contrast kinetic features were extracted from DCE-MRI. Feature selection was performed to identify 10 features for PCa detection in the TZ and PZ, respectively. Two logistic regression classifiers used these features to detect PCa and were evaluated by area under the receiver-operating characteristic curve (AUC). Classifier performance was compared with a zone-ignorant classifier. RESULTS: Radiomic features that were identified as useful for PCa detection differed between TZ and PZ. When classification was performed on a per-voxel basis, a PZ-specific classifier detected PZ tumors on an independent test set with significantly higher accuracy (AUC = 0.61-0.71) than a zone-ignorant classifier trained to detect cancer throughout the entire prostate (P < 0.05). When classifiers were evaluated on MRI data from multiple institutions, statistically similar AUC values (P > 0.14) were obtained for all institutions. CONCLUSION: A zone-aware classifier significantly improves the accuracy of cancer detection in the PZ. LEVEL OF EVIDENCE: 3 Technical Efficacy: Stage 2 J. MAGN. RESON. IMAGING 2017;46:184-193.

Combination of multiparametric MRI and transperineal template-guided mapping biopsy of the prostate to identify candidates for hemi-ablative focal therapy.

OBJECTIVE: To evaluate the accuracy of combined multiparametric magnetic resonance imaging (mpMRI) and transperineal template-guided mapping biopsy (TTMB) for identifying lobes with significant prostate cancer (PCa) for the application of hemi-ablative focal therapy (FT). PATIENTS AND METHODS: From January 2012 to January 2014, 89 consecutive patients, aged ≥40 years, with a PSA level ≤15 ng/mL, underwent in sequential order: mpMRI, TTMB and radical prostatectomy (RP) at a single centre. Analysis was performed on 50 patients who met consensus guidelines for FT. Lobes were stratified into lobes with significant cancer (LSC), lobes with insignificant cancer and lobes with no cancer. Using histopathology at RP, the predictive performance of combined mpMRI + TTMB in identifying LSC was evaluated. RESULTS: The sensitivity, specificity and positive predictive value for mpMRI + TTMB for LSC were 97, 61 and 83%, respectively. The negative predictive value (NPV), the primary variable of interest, for mpMRI + TTMB for LSC was 91%. Of the 50 patients, 21 had significant unilateral disease on mpMRI + TTMB. Two of these 21 patients had significant bilateral disease on RP not identified on mpMRI + TTMB. CONCLUSIONS: In the selection of candidates for FT, a combination of mpMRI and TTMB provides a high NPV in the detection of LSC.

Multiparametric magnetic resonance imaging guided diagnostic biopsy detects significant prostate cancer and could reduce unnecessary biopsies and over detection: a prospective study.

PURPOSE: Multiparametric magnetic resonance imaging appears to improve prostate cancer detection but prospective studies are lacking. We determined the accuracy of multiparametric magnetic resonance imaging for detecting significant prostate cancer before diagnostic biopsy in men with abnormal prostate specific antigen/digital rectal examination. MATERIALS AND METHODS: In this single center, prospective study men older than 40 years with abnormal prostate specific antigen/digital rectal examination and no previous multiparametric magnetic resonance imaging underwent T2-weighted, diffusion-weighted and dynamic contrast enhanced imaging without an endorectal coil. Imaging was allocated alternately to 1.5/3.0 Tesla. Imaging was double reported independently using PI-RADS (Prostate Imaging Reporting and Data System) by specialist radiologists. Transperineal grid directed 30-core biopsy was performed with additional magnetic resonance imaging directed cores for regions of interest outside template locations. Four significant cancer definitions were tested. Chi-square and logistic regression analysis was done. Men undergoing prostatectomy were analyzed. RESULTS: Of the 165 men who enrolled in the study 150 were analyzed. Median age was 62.4 years, median prostate specific antigen was 5.6 ng/ml, 29% of patients had an abnormal digital rectal examination and 88% underwent initial biopsy. Multiparametric magnetic resonance imaging was positive (PI-RADS 3 to 5) in 66% of patients, 61% had prostate cancer and 30% to 41% had significant prostate cancer (definitions 1 to 4). For significant cancer sensitivity was 93% to 96%, specificity was 47% to 53%, and negative and positive predictive values were 92% to 96% and 43% to 57%, respectively (definitions 1 to 4). Radical prostatectomy results in 48 men were similar. Aggregate PI-RADS (4 to 20) performed similarly to overall PI-RADS (1 to 5). Negative and positive predictive values (100% and 71%, respectively) were similar in men at higher risk, defined as prostate specific antigen greater than 10 ng/ml with abnormal digital rectal examination. On multivariate analysis PI-RADS score was associated with significant prostate cancer (p <0.001) but magnet strength was not. Adding PI-RADS to the multivariate model improved the AUC from 0.810 to 0.913 (95% CI 0.038-0.166, p = 0.002). Radiologist agreement was substantial (weighted κ = 0.626). CONCLUSIONS: Multiparametric magnetic resonance imaging reported by expert radiologists achieved an excellent negative predictive value and a moderate positive predictive value for significant prostate cancer at 1.5 and 3.0 Tesla.

Superior quality of life and improved surgical margins are achievable with robotic radical prostatectomy after a long learning curve: a prospective single-surgeon study of 1552 consecutive cases.

BACKGROUND: Comparative studies suggest functional and perioperative superiority of robot-assisted radical prostatectomy (RARP) over open radical prostatectomy (ORP). OBJECTIVE: To determine whether high-volume experienced open surgeons can improve their functional and oncologic outcomes with RARP and, if so, how many cases are required to surpass ORP outcomes and reach the learning curve plateau. DESIGN, SETTING, AND PARTICIPANTS: A prospective observational study compared two surgical techniques: 1552 consecutive men underwent RARP (866) or ORP (686) at a single Australian hospital from 2006 to 2012, by one surgeon with 3000 prior ORPs. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: Demographic and clinicopathologic data were collected prospectively. The Expanded Prostate Cancer Index Composite quality of life (QoL) questionnaire was administered at baseline, 1.5, 3, 6, 12, and 24 mo. Multivariate linear and logistic regression modelled the difference in QoL domains and positive surgical margin (PSM) odds ratio (OR), respectively, against case number. RESULTS AND LIMITATIONS: A total of 1511 men were included in the PSM and 609 in the QoL analysis. RARP sexual function scores surpassed ORP scores after 99 RARPs and increased to a mean difference at 861st case of 11.0 points (95% confidence interval [CI], 5.9-16.1), plateauing around 600-700 RARPs. Early urinary incontinence scores for RARP surpassed ORP after 182 RARPs and increased to a mean difference of 8.4 points (95% CI, 2.1-14.7), plateauing around 700-800 RARPs. The odds of a pT2 PSM were initially higher for RARP but became lower after 108 RARPs and were 55% lower (OR: 0.45; 95% CI, 0.22-0.92) by the 866th RARP. The odds of a pT3/4 PSM were initially higher for RARP but decreased, plateauing around 200-300 RARPs with an OR of 1.15 (0.68-1.95) at the 866th RARP. Limitations include single-surgeon data and residual confounding. CONCLUSIONS: RARP had a long learning curve with inferior outcomes initially, and then showed progressively superior sexual, early urinary, and pT2 PSM outcomes and similar pT3 PSM and late urinary outcomes. Learning RARP was worthwhile for this high-volume surgeon, but the learning curve may not be justifiable for late-career/low-volume surgeons; further studies are needed.

Gene based prediction of clinically localized prostate cancer progression after radical prostatectomy.

PURPOSE: Accurate estimates of recurrence risk are needed for optimal treatment of patients with clinically localized prostate cancer. We combined an established nomogram and what to our knowledge are novel molecular predictors into a new prognostic model of prostate specific antigen recurrence. MATERIALS AND METHODS: We analyzed gene expression profiles from formalin fixed, paraffin embedded, localized prostate cancer tissues to identify genes associated with prostate specific antigen recurrence. Profiles of the identified markers were reproduced by reverse transcriptase-polymerase chain reaction. We used the profiles of 3 of these genes along with output from the Kattan postoperative nomogram to produce a predictive model of prostate specific antigen recurrence. RESULTS: After variable selection we built a model of prostate specific antigen recurrence combining expression values of 3 genes and the postoperative nomogram. The 3-gene plus nomogram model predicted 5-year prostate specific antigen recurrence with a concordance index of 0.77 in a validation set compared to a concordance index of 0.67 for the nomogram. This model identified a subgroup of patients at high risk for recurrence that was not identified by the nomogram. CONCLUSIONS: This new gene based classifier has superior predictive power compared to that of the 5-year nomogram to assess the risk of prostate specific antigen recurrence in patients with organ confined prostate cancer. Our classifier should provide more accurate stratification of patients into high and low risk groups for treatment decisions and adjuvant clinical trials.

Transformation suppressor protein Pdcd4 interferes with JNK-mediated phosphorylation of c-Jun and recruitment of the coactivator p300 by c-Jun.

The transformation suppressor gene Pdcd4 (programmed cell death gene 4) inhibits the tumor-promoter mediated transformation of mouse keratinocytes and has recently been implicated as a potential tumor suppressor gene in the development of human lung cancer. Biochemical analysis has suggested that the Pdcd4 protein is involved in protein translation as well as in nuclear events. Recent work has shown that Pdcd4 suppresses the transactivation of AP-1 responsive promoters by c-Jun, suggesting that the transformation-suppressor activity of Pdcd4 might be due, at least in part, to the inhibition of c-Jun activity. Here, we have addressed how Pdcd4 inhibits c-Jun. We show that Pdcd4 interferes with the phosphorylation of c-Jun by Jun N-terminal kinase (JNK). The inhibition of c-Jun phosphorylation by Pdcd4 appears not to be due to a general suppression of JNK activity, our data rather suggest that Pdcd4 interacts with c-Jun and thereby blocks phosphorylation of c-Jun. In addition to affecting c-Jun phosphorylation, Pdcd4 blocks the recruitment of the coactivator p300 by c-Jun. Taken together, our results strongly suggest that Pdcd4 is directly involved in the regulation of c-Jun activity.