Improved Outcomes with Enzalutamide in Biochemically Recurrent Prostate Cancer.

BACKGROUND: Patients with prostate cancer who have high-risk biochemical recurrence have an increased risk of progression. The efficacy and safety of enzalutamide plus androgen-deprivation therapy and enzalutamide monotherapy, as compared with androgen-deprivation therapy alone, are unknown. METHODS: In this phase 3 trial, we enrolled patients with prostate cancer who had high-risk biochemical recurrence with a prostate-specific antigen doubling time of 9 months or less. Patients were randomly assigned, in a 1:1:1 ratio, to receive enzalutamide (160 mg) daily plus leuprolide every 12 weeks (combination group), placebo plus leuprolide (leuprolide-alone group), or enzalutamide monotherapy (monotherapy group). The primary end point was metastasis-free survival, as assessed by blinded independent central review, in the combination group as compared with the leuprolide-alone group. A key secondary end point was metastasis-free survival in the monotherapy group as compared with the leuprolide-alone group. Other secondary end points were patient-reported outcomes and safety. RESULTS: A total of 1068 patients underwent randomization: 355 were assigned to the combination group, 358 to the leuprolide-alone group, and 355 to the monotherapy group. The patients were followed for a median of 60.7 months. At 5 years, metastasis-free survival was 87.3% (95% confidence interval [CI], 83.0 to 90.6) in the combination group, 71.4% (95% CI, 65.7 to 76.3) in the leuprolide-alone group, and 80.0% (95% CI, 75.0 to 84.1) in the monotherapy group. With respect to metastasis-free survival, enzalutamide plus leuprolide was superior to leuprolide alone (hazard ratio for metastasis or death, 0.42; 95% CI, 0.30 to 0.61; P<0.001); enzalutamide monotherapy was also superior to leuprolide alone (hazard ratio for metastasis or death, 0.63; 95% CI, 0.46 to 0.87; P = 0.005). No new safety signals were observed, with no substantial between-group differences in quality-of-life measures. CONCLUSIONS: In patients with prostate cancer with high-risk biochemical recurrence, enzalutamide plus leuprolide was superior to leuprolide alone with respect to metastasis-free survival; enzalutamide monotherapy was also superior to leuprolide alone. The safety profile of enzalutamide was consistent with that shown in previous clinical studies, with no apparent detrimental effect on quality of life. (Funded by Pfizer and Astellas Pharma; EMBARK ClinicalTrials.gov number, NCT02319837.).

Apalutamide efficacy, safety and wellbeing in older patients with advanced prostate cancer from Phase 3 randomised clinical studies TITAN and SPARTAN.

BACKGROUND: Apalutamide plus androgen-deprivation therapy (ADT) improved outcomes in metastatic castration-sensitive prostate cancer (mCSPC) and non-metastatic castration-resistant PC (nmCRPC) in the Phase 3 randomised TITAN and SPARTAN studies, respectively, and maintained health-related quality of life (HRQoL). Apalutamide treatment effect by patient age requires assessment. METHODS: Post-hoc analysis assessed patients receiving 240 mg/day apalutamide (525 TITAN and 806 SPARTAN) or placebo (527 TITAN and 401 SPARTAN) with ongoing ADT, stratified by age groups. Prostate-specific antigen declines, radiographic progression-free survival, metastasis-free survival, overall survival (OS), HRQoL and safety were assessed using descriptive statistics, Kaplan-Meier method, Cox proportional-hazards model and mixed-effects model for repeated measures. RESULTS: Hazard ratios (95% confidence intervals) generally favoured apalutamide plus ADT versus ADT alone across all endpoints regardless of age; e.g., OS values were 0.57 (0.40-0.80), 0.70 (0.54-0.91) and 0.74 (0.40-1.39) (TITAN) and 0.39 (0.19-0.78), 0.89 (0.69-1.16) and 0.81 (0.58-1.15) (SPARTAN) in patients aged <65, 65-79 and ≥80 years. Regardless of age, apalutamide also maintained HRQoL and was tolerated well with a potential trend in rates of adverse events increasing with age. Limitations include post-hoc nature and variability in sample size of age groups. CONCLUSIONS: Apalutamide plus ADT was an effective and well-tolerated option maintaining HRQoL in patients with mCSPC and nmCRPC regardless of age. CLINICAL TRIAL REGISTRATION: TITAN (NCT02489318); SPARTAN (NCT01946204).

Real-world outcomes of sipuleucel-T treatment in PROCEED, a prospective registry of men with metastatic castration-resistant prostate cancer.

BACKGROUND: The large registry, PROVENGE Registry for the Observation, Collection, and Evaluation of Experience Data (PROCEED)(NCT01306890), evaluated sipuleucel-T immunotherapy for asymptomatic/minimally symptomatic metastatic castration-resistant prostate cancer (mCRPC). METHODS: PROCEED enrolled patients with mCRPC receiving 3 biweekly sipuleucel-T infusions. Assessments included overall survival (OS), serious adverse events (SAEs), cerebrovascular events (CVEs), and anticancer interventions (ACIs). Follow-up was for ≥3 years or until death or study withdrawal. RESULTS: In 2011-2017, 1976 patients were followed for 46.6 months (median). The median age was 72 years, and the baseline median prostate-specific antigen level was 15.0 ng/mL; 86.7% were white, and 11.6% were African American. Among the patients, 1902 had 1 or more sipuleucel-T infusions. The median OS was 30.7 months (95% confidence interval [CI], 28.6-32.2 months). Known prognostic factors were independently associated with OS in a multivariable analysis. Among the 1255 patients who died, 964 (76.8%) died of prostate cancer (PC) progression. The median time from the first infusion to PC death was 42.7 months (95% CI, 39.4-46.2 months). The incidence of sipuleucel-T-related SAEs was 3.9%. The incidence of CVEs was 2.8%, and the rate per 100 person-years was 1.2 (95% CI, 0.9-1.6). The CVE incidence among 11,972 patients with mCRPC from the Surveillance, Epidemiology, and End Results-Medicare database was 2.8%; the rate per 100 person-years was 1.5 (95% CI, 1.4-1.7). One or more ACIs (abiraterone, enzalutamide, docetaxel, cabazitaxel, or radium 223) were received by 77.1% of the patients after sipuleucel-T; 32.5% and 17.4% of the patients experienced 1- and 2-year treatment-free intervals, respectively. CONCLUSIONS: PROCEED provides contemporary survival data for sipuleucel-T-treated men in a real-world setting of new life-prolonging agents, which will be useful in discussing treatment options with patients and in powering future trials with sipuleucel-T. The safety and tolerability of sipuleucel-T in PROCEED were consistent with previous findings.

Combination Treatment with Sipuleucel-T and Abiraterone Acetate or Enzalutamide for Metastatic Castration-Resistant Prostate Cancer: STAMP and STRIDE Trials.

PURPOSE: We present long-term outcomes from 2 randomized studies [STAMP (with abiraterone, NCT01487863) and STRIDE (with enzalutamide, NCT01981122)] that were performed to study the impact of sequential or concurrent administration of androgen receptor-targeting agents (ARTAs) on sipuleucel-T immune response and overall survival (OS) in metastatic castration-resistant prostate cancer (mCRPC). PATIENTS AND METHODS: Sipuleucel-T was administered per current prescribing information. Results from STRIDE are presented together with updated STAMP results. Survival status of patients was updated using demographic information to query the National Death Index (NDI). Kaplan-Meier methodology was used to analyze survival. RESULTS: Updated data reduced patient censoring in each study compared with the original analyses; the 95% confidence intervals (CIs) for OS are now estimable. Updated median OS (95% CI) is 33.3 (24.1-40.7) months for STAMP and 32.5 (26.0-45.1) months for STRIDE. There was no notable impact on median OS [HR, 0.727 (0.458-1.155); P = 0.177, reference = STRIDE]. OS with sequential administration was similar to concurrent administration [NDI update: HR, 0.963 (0.639-1.453); P = 0.845, reference = concurrent arm]. Sipuleucel-T potency, measured as antigen-presenting cell (APC) activation, was higher in subsequent infusions compared with the first infusion. Humoral responses (IgG + IgM antibody titers) to PA2024 and prostatic acid phosphatase were significantly elevated versus baseline. No new safety signals were observed. CONCLUSIONS: Median OS was consistent regardless of whether the agents were administered sequentially or concurrently, including after NDI update. Results suggest that sipuleucel-T induces an immunologic prime-boost effect after initial sipuleucel-T exposure, even when combined with ARTAs.

Enzalutamide and Quality of Life in Biochemically Recurrent Prostate Cancer.

BACKGROUND: EMBARK, a controlled trial reported elsewhere, showed enzalutamide plus leuprolide (combination) and enzalutamide monotherapy prolonged metastasis-free survival versus placebo plus leuprolide (alone) in patients with high-risk biochemically recurrent prostate cancer. Health-related quality of life was also analyzed but not reported. METHODS: In EMBARK, patients with biochemical recurrence (prostate-specific antigen doubling time of ≤9 months) were randomly assigned (1:1:1) to combination (n=355), leuprolide-alone (n=358), or enzalutamide monotherapy (n=355). In this article we provide the patient-reported outcomes (PROs) from EMBARK at baseline and every 12 weeks until metastasis or death. The key end point was time to first and confirmed clinically meaningful deterioration (TTFD/TTCD) in pain and health-related quality of life using four PRO measures and predefined thresholds. RESULTS: At baseline, all groups had high health-related quality of life. For worst pain, the median TTFD was 19.35 months with leuprolide alone, 13.93 months with combination (hazard ratio, 1.08; 95% confidence interval [CI], 0.89 to 1.30) and 16.59 months with monotherapy (hazard ratio, 1.09; 95% CI, 0.90 to 1.31). The median TTCD was 66.27 months with leuprolide alone, 80.00 months with combination (hazard ratio, 0.82; 95% CI, 0.65 to 1.04), and 60.91 months with monotherapy (hazard ratio, 1.02; 95% CI, 0.82 to 1.28). For Functional Assessment of Cancer Therapy­Prostate total score, the median TTFD was 11.10 months with leuprolide alone, 8.31 months with combination (hazard ratio, 1.14; 95% CI, 0.95 to 1.36), and 8.38 months with monotherapy (hazard ratio, 1.17; 95% CI, 0.98 to 1.39). The median TTCD was 36.53 months with leuprolide alone, 38.77 months with combination (hazard ratio, 1.04; 95% CI, 0.85 to 1.28), and 30.55 months with monotherapy (hazard ratio, 1.16; 95% CI, 0.95 to 1.41). CONCLUSIONS: The PROs from EMBARK show that both enzalutamide combination and monotherapy versus leuprolide alone, with oncologic benefits noted above, preserved high health-related quality of life in patients with high-risk biochemical recurrence of prostate cancer. (Funded by Pfizer and Astellas Pharma; ClinicalTrials.gov number, NCT02319837.)

Development and evaluation of the MiCheck® Prostate test for clinically significant prostate cancer.

BACKGROUND: There is a clinical need to identify patients with an elevated PSA who would benefit from prostate biopsy due to the presence of clinically significant prostate cancer (CSCaP). We have previously reported the development of the MiCheck® Test for clinically significant prostate cancer. Here, we report MiCheck's further development and incorporation of the Roche Cobas standard clinical chemistry analyzer. OBJECTIVES: To further develop and adapt the MiCheck® Prostate test so it can be performed using a standard clinical chemistry analyzer and characterize its performance using the MiCheck-01 clinical trial sample set. DESIGN, SETTINGS, AND PARTICIPANTS: About 358 patient samples from the MiCheck-01 US clinical trial were used for the development of the MiCheck® Prostate test. These consisted of 46 controls, 137 non-CaP, 62 non-CSCaP, and 113 CSCaP. METHODS: Serum analyte concentrations for cellular growth factors were determined using custom-made Luminex-based R&D Systems multi-analyte kits. Analytes that can also be measured using standard chemistry analyzers were examined for their ability to contribute to an algorithm with high sensitivity for the detection of clinically significant prostate cancer. Samples were then re-measured using a Roche Cobas analyzer for development of the final algorithm. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: Logistic regression modeling with Monte Carlo cross-validation was used to identify Human Epidydimal Protein 4 (HE4) as an analyte able to significantly improve the algorithm specificity at 95% sensitivity. A final model was developed using analyte measurements from the Cobas analzyer. RESULTS: The MiCheck® logistic regression model was developed and consisted of PSA, %free PSA, DRE, and HE4. The model differentiated clinically significant cancer from no cancer or not-clinically significant cancer with AUC of 0.85, sensitivity of 95%, and specificity of 50%. Applying the MiCheck® test to all evaluable 358 patients from the MiCheck-01 study demonstrated that up to 50% of unnecessary biopsies could be avoided while delaying diagnosis of only 5.3% of Gleason Score (GS) ≥3+4 cancers, 1.8% of GS≥4+3 cancers and no cancers of GS 8 to 10. CONCLUSIONS: The MiCheck® Prostate test identifies clinically significant prostate cancer with high sensitivity and negative predictive value (NPV). It can be performed in a clinical laboratory using a Roche Cobas clinical chemistry analyzer. The MiCheck® Prostate test could assist in reducing unnecessary prostate biopsies with a marginal number of patients experiencing a delayed diagnosis.

A comparison of prostate health index, total PSA, %free PSA, and proPSA in a contemporary US population-The MiCheck-01 prospective trial.

BACKGROUND: Increasing numbers of patients are presenting with aggressive prostate cancer (CaP); therefore, there exists a need to optimally identify these patients pre-biopsy. OBJECTIVES: To compare the accuracy of total prostate specific antigen (PSA), %free PSA, and prostate health index (PHI) to differentiate between patients without CaP, with non-aggressive (Gleason 3 + 3, non-AgCaP) and with aggressive (Gleason ≥ 3 + 4, AgCaP) in a contemporary US population. DESIGN, SETTINGS, AND PARTICIPANTS: Serum samples were collected from 332 US patients scheduled for biopsy due to an elevated age-adjusted PSA. Site and Central biopsy pathologic assessment were performed. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: Testing of PSA, free PSA, proPSA, and PHI was performed along with central pathology review. Test performance using logistic regression analysis for differentiating CaP from non-CaP as well as non-AgCaP from AgCaP was evaluated. RESULTS AND LIMITATIONS: Central pathology review resulted in 32 upgrades including 14 Gleason 3 + 3 scores being upgraded to AgCaP with final distribution of 148 no-CaP, 64 non-AgCaP, and 120 AgCaP patients. Receiver operator curve (ROC) analysis of the different tests showed that PHI performed best at differentiating CaP from no-CaP subjects (area under the receiver operator curve 0.79). In contrast, the different tests were essentially equivalent in differentiating AgCaP vs. non-AgCaP. CONCLUSIONS: In this recent US study of prebiopsy patients we observed a high proportion of AgCaP patients consistent with previous studies in contemporary US populations. Central Gleason review is recommended for multi-institutional studies comparing biomarkers. PHI was superior to PSA, free PSA, %free PSA, and proPSA in detecting CaP in this population but was not superior at differentiating AgCaP from non-AgCaP.

Development and evaluation of the MiCheck test for aggressive prostate cancer.

BACKGROUND: A clinical need exists for a biomarker test to accurately delineate aggressive prostate cancer (AgCaP), and thus better assist clinicians and patients decision-making on whether to proceed to prostate biopsy. OBJECTIVES: To develop a blood test for AgCaP and compare to PSA, %free PSA, proPSA, and prostate health index (PHI) tests. DESIGN, SETTINGS AND PARTICIPANTS: Patient samples from the MiCheck-01 trial were used for development of the MiCheck test. METHODS: Serum analyte concentrations for cellular growth factors were determined using a custom-made Luminex-based R&D Systems multianalyte kit. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: Bayesian model averaging and random forest approaches were used to identify clinical factors and growth factors able to distinguish between men with AgCaP (Gleason Score [GS] ≥3+4) from those with non-AgCaP (GS 3+3). Logistic regression and Monte Carlo cross-validation identified variable combinations in order to able to maximize differentiation of AgCaP from non-AgCaP. RESULTS: The MiCheck logistic regression model was developed and comprises the following variables: serum prostate-specific antigen (PSA), patient age, Digital Rectal Exam (DRE) status, Leptin, IL-7, vascular endothelial growth factor, and Glypican-1. The model differentiated AgCaP from non-AgCaP with an area under the curve of 0.83 and was superior to PSA, %free PSA and PHI in all patient groups, regardless of PSA range. Applying the MiCheck test to all evaluable biopsy patients from the MiCheck-01 study demonstrated that up to 30% of biopsies could be avoided while delaying diagnosis of only 6.8% of GS ≥3+4 cancers, 5% of GS ≥4+3 cancers and no cancers of GS 8 or higher. CONCLUSIONS: The MiCheck test outperforms PSA, %free PSA and PHI tests in differentiating AgCaP vs. non-AgCaP patients. The MiCheck test could result in a significant number of biopsies being avoided with a low number of patients experiencing a delayed diagnosis.

Survival of African-American and Caucasian men after sipuleucel-T immunotherapy: outcomes from the PROCEED registry.

PURPOSE: African Americans experience greater prostate cancer risk and mortality than do Caucasians. An analysis of pooled phase III data suggested differences in overall survival (OS) between African American and Caucasian men receiving sipuleucel-T. We explored this in PROCEED (NCT01306890), an FDA-requested registry in over 1900 patients with metastatic castration-resistant prostate cancer (mCRPC) treated with sipuleucel-T. PATIENTS AND METHODS: OS for patients who received ≥1 sipuleucel-T infusion was compared between African American and Caucasian men using an all patient set and a baseline prostate-specific antigen (PSA)-matched set (two Caucasians to every one African American with baseline PSAs within 10% of each other). Univariable and multivariable analyses were conducted. Survival data were examined using Kaplan-Meier and Cox proportional hazard methodologies. RESULTS: Median follow-up was 46.6 months. Overall survival differed between African American and Caucasian men with hazard ratios (HR) of 0.81 (95% confidence interval [CI]: 0.68-0.97, P = 0.03) in the all patient set and 0.70 (95% CI: 0.57-0.86, P < 0.001) in the PSA-matched set. Median OS was longer in African Americans than in Caucasian men for both analysis sets, e.g., 35.3 and 25.8 months, respectively, in the PSA-matched set. Similar results were observed in the all patient set. Differences were larger when treatment began at lower baseline PSA; curves were more similar among patients with higher baseline PSA. In patients with baseline PSA below the median, the HR was 0.52 (95% CI: 0.37-0.72, P < 0.001), with median OS of 54.3 versus 33.4 months. Known prognostic factors and African American race (multivariable analyses; HR: 0.60, 95% CI: 0.48-0.74, P < 0.001) were independently associated with OS. Use of post-sipuleucel-T anticancer interventions was balanced between races. CONCLUSION: In this exploratory analysis of a registry including nearly 12% African American men with mCRPC, OS was significantly different between African Americans and Caucasians, indicating further research is warranted.

Effectiveness of Subcutaneously Administered Leuprolide Acetate to Achieve Low Nadir Testosterone in Prostate Cancer Patients.

Evidence suggests lower nadir testosterone levels during the first year of androgen deprivation therapy improve advanced prostate cancer clinical outcomes. We evaluated pivotal trials for subcutaneously administered leuprolide acetate (1-, 3-, 4-, and 6-month doses) to determine nadir testosterone levels. Pooled analysis showed 99%, 97%, and 91% of patients reached nadir testosterone ≤20, ≤10, and ≤5 ng/dL respectively (median ≤3 ng/dL). Across all available categories, $88% of patients reached nadir testosterone ≤5 ng/dL, and <3% experienced a microsurge. Achievement and maintenance of low nadir testosterone levels may improve progression-free survival and time to onset of castrate-resistant prostate cancer.

Absorbable Hydrogel Spacer Use in Prostate Radiotherapy: A Comprehensive Review of Phase 3 Clinical Trial Published Data.

OBJECTIVE: To provide an update on SpaceOAR System, a Food and Drug Administration-approved hydrogel indicated to create distance between the prostate and the rectum which has been studied in phase 2 and 3 clinical trials. Here, we review and summarize these clinical results including the safety of prostate-rectum spacer application technique, the implant quality and resulting rectal dose reduction, acute and long-term rectal, urinary, and sexual toxicity, as well as patient-reported outcomes. MATERIALS AND METHODS: A prospective, randomized patient-blinded clinical study was performed comparing image-guided intensity modulated prostate radiotherapy (79.2 Gy in 44 fractions) in men with or without prostate-rectum hydrogel spacer. Patients were followed up for 3 years, allowing assessment of long-term safety and efficacy. RESULTS: Spacer application was well tolerated with a 99% technical success rate. The mean additional space created between the prostate and the rectum was just over 1 cm, which allowed significant rectum and penile bulb radiation dose reduction, resulting in less acute pain, lower rates of late rectal toxicity, and improved bowel and urinary quality of life (QOL) scores from 6 months onward. Improvements in sexual QOL were also observed at 37 months in baseline-potent men, with 37.5% of control and 66.7% of spacer men capable of "erections sufficient for intercourse." CONCLUSION: Prostate-rectum hydrogel spacer application is a relatively safe technical procedure that is well tolerated and has a high technical success rate. Spacer application significantly reduces rectal radiation dose and results in long-term reductions in rectal toxicity, as well as improvements in bowel, urinary, and sexual QOL.

Hydrogel Spacer Application Technique, Patient Tolerance and Impact on Prostate Intensity Modulated Radiation Therapy: Results from a Prospective, Multicenter, Pivotal Randomized Controlled Trial.

INTRODUCTION: We evaluate the safety, tolerability and impact on therapy of an absorbable hydrogel perirectal spacer (SpaceOAR® system) designed to reduce the rectal radiation dose during prostate cancer radiotherapy. METHODS: A multicenter, pivotal, randomized controlled trial was conducted in 222 men with stage T1 or T2 prostate cancer treated to 79.2 Gy with image guided intensity modulated radiation therapy in 44 fractions. Patients were randomized 2:1 to receive fiducial markers and perirectal spacer injection (spacer group) or fiducial markers alone (control group). Spacer placement, tolerability, perirectal space creation, impact on rectal dose and impact on quality of life were assessed. RESULTS: Most spacer procedures were conducted with the patient under general or local anesthesia. Procedures were rated easy or very easy in 98.7% of cases with a 99.3% success rate. Mild transient rectal events were noted in 10% of patients in the spacer group (eg pain, discomfort). Mean perirectal space was 12.6 mm after implant and 10.9 mm at 12.4 weeks with absorption at 12 months. A 25% or greater reduction in rectal V70 dose was produced in 97.3% of patients in the spacer group. The spacer group experienced a significant reduction in late rectal toxicity severity (p=0.044) as well as lower rates of decrease in bowel quality of life at 6, 12 and 15 months compared to the control group. There were no unanticipated adverse spacer effects or spacer related adverse events. CONCLUSIONS: Hydrogel spacer application was straightforward and repeatable, resulting in consistent perirectal space creation and rectal dose reduction. Spacer application has the potential to improve prostate radiotherapy outcomes and enable advanced radiotherapy protocols.

Sipuleucel-T for the Treatment of Patients With Metastatic Castrate-resistant Prostate Cancer: Considerations for Clinical Practice.

Sipuleucel-T treatment is associated with a significant and consistent survival benefit in patients with metastatic castrate-resistant prostate cancer. Most adverse events are infusion related, manageable, and of short duration. Early screening and diagnosis of metastatic disease is important, as the greatest survival benefit may occur in patients with a lower disease burden. The short duration of sipuleucel-T treatment facilitates the use of subsequent therapies. Sipuleucel-T is now being used in the clinic for patients with a lower disease burden. We present our own experience with the use of sipuleucel-T in the setting of a large urology practice.

A multi-institutional prospective trial in the USA confirms that the 4Kscore accurately identifies men with high-grade prostate cancer.

BACKGROUND: The 4Kscore combines measurement of four kallikreins in blood with clinical information as a measure of the probability of significant (Gleason ≥7) prostate cancer (PCa) before prostate biopsy. OBJECTIVE: To perform the first prospective evaluation of the 4Kscore in predicting Gleason ≥7 PCa in the USA. DESIGN, SETTING, AND PARTICIPANTS: Prospective enrollment of 1012 men scheduled for prostate biopsy, regardless of prostate-specific antigen level or clinical findings, was conducted at 26 US urology centers between October 2013 and April 2014. INTERVENTION: The 4Kscore. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: The primary outcome was Gleason ≥7 PCa on prostate biopsy. The area under the receiver operating characteristic curve, risk calibration, and decision curve analysis (DCA) were determined, along with comparisons of probability cutoffs for reducing the number of biopsies and their impact on delaying diagnosis. RESULTS AND LIMITATIONS: Gleason ≥7 PCa was found in 231 (23%) of the 1012 patients. The 4Kscore showed excellent calibration and demonstrated higher discrimination (AUC 0.82) and net benefit compared to a modified Prostate Cancer Prevention Trial Risk Calculator 2.0 model and standard of care (biopsy for all men) according to DCA. A possible reduction of 30-58% in the number biopsies was identified with delayed diagnosis in only 1.3-4.7% of Gleason ≥7 PCa cases, depending on the threshold used for biopsy. Pathological assessment was performed according to the standard of care at each site without centralized review. CONCLUSION: The 4Kscore showed excellent diagnostic performance in detecting significant PCa. It is a useful tool in selecting men who have significant disease and are most likely to benefit from a prostate biopsy from men with no cancer or indolent cancer. PATIENT SUMMARY: The 4Kscore provides each patient with an accurate and personalized measure of the risk of Gleason ≥7 cancer to aid in decision-making regarding the need for prostate biopsy.

The Rationale for Optimal Combination Therapy With Sipuleucel-T for Patients With Castration-resistant Prostate Cancer.

Immunotherapy encourages the recipient's own immune response to destroy cancer cells, and current evidence suggests that immunotherapies may be most beneficial in early metastatic castration-resistant prostate cancer (mCRPC). Sipuleucel-T is the first therapeutic cancer vaccine to be approved by both the US Food and Drug Administration and European Medicines Agency for the treatment of asymptomatic or minimally symptomatic mCRPC. Combining immunotherapy with other treatments may have potent anticancer effects; cytoreductive therapies can release tumor antigens and promote a proinflammatory environment that could augment immunotherapies. However, some cytoreductive agents or coadministered drugs may be immunosuppressive. Understanding these interactions between different mCRPC treatment modalities may offer further potential to improve patient outcomes.