Optimising preoperative risk stratification tools for prostate cancer using mpMRI.

PURPOSE: To improve preoperative risk stratification for prostate cancer (PCa) by incorporating multiparametric MRI (mpMRI) features into risk stratification tools for PCa, CAPRA and D'Amico. METHODS: 807 consecutive patients operated on by robot-assisted radical prostatectomy at our institution during the period 2010-2015 were followed to identify biochemical recurrence (BCR). 591 patients were eligible for final analysis. We employed stepwise backward likelihood methodology and penalised Cox cross-validation to identify the most significant predictors of BCR including mpMRI features. mpMRI features were then integrated into image-adjusted (IA) risk prediction models and the two risk prediction tools were then evaluated both with and without image adjustment using receiver operating characteristics, survival and decision curve analyses. RESULTS: 37 patients suffered BCR. Apparent diffusion coefficient (ADC) and radiological extraprostatic extension (rEPE) from mpMRI were both significant predictors of BCR. Both IA prediction models reallocated more than 20% of intermediate-risk patients to the low-risk group, reducing their estimated cumulative BCR risk from approximately 5% to 1.1%. Both IA models showed improved prognostic performance with a better separation of the survival curves. CONCLUSION: Integrating ADC and rEPE from mpMRI of the prostate into risk stratification tools improves preoperative risk estimation for BCR. KEY POINTS: • MRI-derived features, ADC and EPE, improve risk stratification of biochemical recurrence. • Using mpMRI to stratify prostate cancer patients improves the differentiation between risk groups. • Using preoperative mpMRI will help urologists in selecting the most appropriate treatment.

A positive Real-Time Elastography (RTE) combined with a Prostate Cancer Gene 3 (PCA3) score above 35 convey a high probability of intermediate- or high-risk prostate cancer in patient admitted for primary prostate biopsy.

BACKGROUND: The standard of care in patients with suspected prostate cancer (PCa) is systematic prostate biopsies. This approach leads to unnecessary biopsies in patients without PCa and also to the detection of clinical insignificant PCa. Better tools are wanted. We have evaluated the performance of real-time elastography (RTE) combined with prostate cancer gene 3 (PCA3) in an initial biopsy setting with the goal of better identifying patients in need of prostate biopsies. METHODS: 127 patients were included in this study; three were excluded because of not measureable PCA3 score leading to 124 evaluable patients. A cut-off value of 35 was used for PCA3. All patients were examined with a Hitachi Preirus with an endfire probe for RTE, a maximum of five targeted biopsies were obtained from suspicious lesions detected by RTE. All patients then had a 10-core systematic biopsy performed by another urologist unaware of the RTE results. The study includes follow-up data for a minimum of three years; all available histopathological data are included in the analysis. RESULTS: There was a significant difference in PCA3 score: 26.6 for benign disease, 73.6 for cancer patients (p < 0.001). 70 patients (56 %) were diagnosed with prostate cancer in the study period, 21 (30 %) low-risk, 32 (46 %) intermediate-risk and 17 (24 %) high-risk. RTE and PCA3 were significant markers for predicting intermediate- and high-risk PCa (p = 0.001). The combination of RTE and PCA3 had a sensitivity of 96 % and a negative predictive value (NPV) of 90 % for the group of intermediate- and high-risk PCa together and a NPV for high-risk PCa of 100 %. If both parameters are positive there is a high probability of detecting intermediate- or high-risk PCa, if both parameters are negative there is only a small chance of missing prostate cancer with documented treatment benefit. CONCLUSIONS: RTE and PCA3 may be used as pre-biopsy examinations to reduce the number of prostate biopsies.

1.5-T multiparametric MRI using PI-RADS: a region by region analysis to localize the index-tumor of prostate cancer in patients undergoing prostatectomy.

BACKGROUND: The use of multiparametric magnetic resonance imaging (mpMRI) to detect and localize prostate cancer has increased in recent years. In 2010, the European Society of Urogenital Radiology (ESUR) published guidelines for mpMRI and introduced the Prostate Imaging Reporting and Data System (PI-RADS) for scoring the different parameters. PURPOSE: To evaluate the reliability and diagnostic performance of endorectal 1.5-T mpMRI using the PI-RADS to localize the index tumor of prostate cancer in patients undergoing prostatectomy. MATERIAL AND METHODS: This institutional review board IRB-approved, retrospective study included 63 patients (mean age, 60.7 years, median PSA, 8.0). Three observers read mpMRI parameters (T2W, DWI, and DCE) using the PI-RADS, which were compared with the results from whole-mount histopathology that analyzed 27 regions of interest. Inter-observer agreement was calculated as well as sensitivity, specificity, positive predictive value (PPV), and negative predicted value (NPV) by dichotomizing the PI-RADS criteria scores ≥3. A receiver-operating curve (ROC) analysis was performed for the different MR parameters and overall score. RESULTS: Inter-observer agreement on the overall score was 0.41. The overall score in the peripheral zone achieved sensitivities of 0.41, 0.60, and 0.55 with an NPV of 0.80, 0.84, and 0.83, and in the transitional zone, sensitivities of 0.26, 0.15, and 0.19 with an NPV of 0.92, 0.91, and 0.92 for Observers 1, 2, and 3, respectively. The ROC analysis showed a significantly increased area under the curve (AUC) for the overall score when compared to T2W alone for two of the three observers. CONCLUSION: 1.5 T mpMRI using the PI-RADS to localize the index tumor achieved moderate reliability and diagnostic performance.

A positive real-time elastography is an independent marker for detection of high-risk prostate cancers in the primary biopsy setting.

OBJECTIVE: To evaluate the performance of real-time elastography (RTE) in an initial biopsy setting. PATIENTS AND METHODS: In the period from February 2011 to June 2012, 127 consecutive patients were included in the study. We used a Hitachi Preirus with Hi-RTE module, a prostate end-fire transrectal probe was used for RTE and for targeted biopsies, and a simultaneous biplane probe was used for the standard systematic biopsies. The peripheral zone of the prostate was divided into six regions, and each biopsy obtained was referred to a specific region. All patients were first examined with RTE and, if cancer was suspected, targeted biopsies were taken. A standard systematic 10-core biopsy was then taken in all patients. RESULTS: In all, 64 (50%) patients were diagnosed with prostate cancer in the initial biopsy setting. Three patients were diagnosed solely on RTE-targeted biopsies, 31 were found only in systematic biopsies, and 30 were correctly diagnosed with both methods. In the RTE-positive group there was a significantly higher frequency of positive cores, a lower prostate volume, a higher Gleason score, and a higher fraction of cancer tissue in each core. In a multiple regression model RTE was an independent marker for high-risk cancer. The sensitivity of 42% for all prostate cancers increased to 60% for high-grade prostate cancers. Similarly, the negative predictive value increased from 79% to 97%. An additional eight patients were diagnosed with prostate cancer during the study period. CONCLUSIONS: A positive RTE is an independent marker for detection of high-risk prostate cancer, and a negative RTE argues against such. RTE with targeted biopsies cannot replace systematic biopsies, but provides valuable additional information about the tumours.

Ten-Year Results From a Phase II Study on Image Guided, Intensity Modulated Radiation Therapy With Simultaneous Integrated Boost in High-Risk Prostate Cancer.

PURPOSE: There is no consensus on how to treat high-risk prostate cancer, and long-term results from hypofractionated radiation therapy are lacking. We report 10-year results after image guided, intensity modulated radiation therapy with hypofractionated simultaneous integrated boost and elective pelvic field. METHODS AND MATERIALS: Between 2007 and 2009, 97 consecutive patients with high-risk prostate cancer were included, treated with 2.7 to 2.0 Gy × 25 Gy to the prostate, seminal vesicles, and elective pelvic field. Toxicity was scored according to Radiation Therapy Oncology Group criteria and biochemical disease-free survival (BFS) defined by the Phoenix definition. Patients were subsequently divided into 3 groups: high risk (HR; n = 32), very high risk (VHR; n = 50), and N+/s-prostate-specific antigen (PSA) ≥100 (n = 15). Differences in outcomes were examined using Kaplan-Meier analyses. RESULTS: BFS in the patients at HR and VHR was 64%, metastasis-free survival 80%, prostate cancer-specific survival 90%, and overall survival (OS) 72%. VHR versus HR subgroups demonstrated significantly different BFS, 54% versus 79% (P = .01). Metastasis-free survival and prostate cancer-specific survival in the VHR group versus HR group were 76% versus 87% (P = .108) and 74% versus 100% (P = .157). Patients reaching nadir PSA <0.1 (n = 80) had significantly better outcomes than the rest (n = 17), with BFS 70% versus 7% (P < .001). Acute grade 2 gastrointestinal tract (GI) and genitourinary tract (GU) toxicity occurred in 27% and 40%, grade 3 GI and GU toxicity in 1% and 3%. Late GI and GU grade 2 toxicity occurred in 1% and 8%. CONCLUSIONS: High-risk prostate cancer patients obtained favorable 10-year outcomes with low toxicity. There were significantly better results in the HR versus the VHR group, both better than the N+/PSA ≥100 group. A nadir PSA value < 0.1 predicted good prognosis.

Prostate cancer antigen-3 (PCA3) and PCA3-based nomograms in the diagnosis of prostate cancer: an external validation of Hansen's nomogram on a Norwegian cohort.

OBJECTIVE: The aim of this study was to test the ability of prostate cancer antigen-3 (PCA3) and Hansen's PCA3-based nomogram to predict prostate cancer (PCa) probability in a Norwegian cohort, with the goal of reducing unnecessary biopsies. MATERIAL AND METHODS: Altogether, 127 consecutive patients were recruited to this study at Haukeland University Hospital, Norway. Prostate-specific antigen (PSA), PCA3 score, digital rectal examination (DRE), prostate volume (Pvol) and age were determined. All patients had an extended 10-core biopsy. The performance of PCA3 score and Hansen's nomogram was tested. RESULTS: There were 124 evaluable patients. Among these, 59 patients had PCa on the initial biopsies. Mean PSA, PCA3 score and age were significantly higher and Pvol was significantly lower in patients with PCa. PCA3 scores of 35 and 21 led to a sensitivity of 71% and 81% and specificity of 72% and 55%, respectively. Hansen's nomogram gave an area under the curve (AUC) of 0.806. The intraclass correlation was 0.959 (Cronbach's alpha). Applied to this material, PCa would be missed in 15.2% of patients when applying the suggested threshold probability of 30%, among whom 66.7% had high-grade PCa. With a threshold probability of 20% only one patient had PCa and this was low grade. CONCLUSIONS: Hansen's PCA3-based nomogram is valid for this cohort. A threshold probability of 20% seems more adequate than 30% for this less screened cohort. PCA3 score only affects the biopsy indication in some patients and is recommended only for this subset. The results need to be confirmed in a larger study.

Combination of real-time elastography and urine prostate cancer gene 3 (PCA3) detects more than 97% of significant prostate cancers.

OBJECTIVE: The prostate cancer gene 3 (PCA3) score in urine is a promising biomarker for prostate cancer. Real-time elastography (RTE) is a well-documented ultrasound modality. The objective of this study was to evaluate the ability to detect significant cancer foci in the prostate with these methods alone and in combination. MATERIAL AND METHODS: From September 2009 to September 2010, 40 patients planned for radical prostatectomy underwent a PCA3 urine test and RTE before operation. A Hitachi EUB-8500 with prostate end-fire transrectal probe was used. The PCA3 score was evaluated with a standard cut-off value of 35. RTE was evaluated in correlation with whole-mount section pathology. Three patients fulfilled the criteria for insignificant prostate cancer and were excluded from the study. RESULTS: The PCA3 score was increased in 26 patients (70%). RTE identified at least one tumour in 33 out of 37 patients (89%). RTE detected the largest tumour in 27 out of 37 patients (73%). More than one cancer was present in 29 patients and RTE identified more than one tumour in 13 of these. The RTE was false positive in four patients. The PCA3 score was increased in three out of four false-negative RTE patients. By combining both methods, 36 out of 37 patients (97%) with significant prostate cancer were detected. CONCLUSIONS: The combination of PCA3 score and RTE detected 97% of significant prostate cancers. The combinative use of RTE and PCA3 will be further investigated in an unselected series of men with suspected prostate cancer.