Establishment of primary prostate epithelial and tumorigenic cell lines using a non-viral immortalization approach

BACKGROUND

Research on prostate cancer is mostly performed using cell lines derived from metastatic disease, not reflecting stages of tumor initiation or early progression. Establishment of cancer cell lines derived from the primary tumor site has not been described so far. By definition, cancer cells are able to be cultured indefinitely, whereas normal epithelial cells undergo senescence in vitro. Epithelial cells can be immortalized, accomplished by using viral integration of immortalization factors. Viral approaches, however, might be impaired by regulatory and safety issues as well as random integration into regulatory genetic elements, modifying precise gene expression. We intend to use surgical specimen of prostate cancer patients to (i) prove for establishment of cancer cell lines, and (ii) perform non-viral, Sleeping Beauty (SB) transposase-based immortalization of prostate epithelial cells.

METHODS

Radical prostatectomy samples of prostate cancer patients (n = 4) were dissociated and cultured in vitro. Cells were cultivated either without or after non-viral, Sleeping-Beauty transposase-based stable transfection with immortalization factors SV40LT and hTERT. Established cell lines were analyzed in vitro and in vivo for characteristics of prostate (cancer) cells.

RESULTS

Initial cell cultures without genetic manipulation underwent senescence within ≤ 15 passages, demonstrating inability to successfully derive primary prostate cancer cell lines. By using SB transposase-based integration of immortalization factors, we were able to establish primary prostate cell lines. Three out of four cell lines displayed epithelial characteristics, however without expression of prostate (cancer) characteristics, e.g., androgen receptor. In vivo, one cell line exhibited tumorigenic potential, yet characteristics of prostate adenocarcinoma were absent.

CONCLUSION

Whereas no primary prostate cancer cell line could be established, we provide for the first-time immortalization of primary prostate cells using the SB transposase system, thereby preventing regulatory and molecular issues based on viral immortalization approaches. Although, none of the newly derived cell lines demonstrated prostate cancer characteristics, tumor formation was observed in one cell line. Given the non-prostate adenocarcinoma properties of the tumor, cells have presumably undergone oncogenic transformation rather than prostate cancer differentiation. Still, these cell lines might be used as a tool for research on prostate cancer initiation and early cancer progression.

Safety and Efficacy of Extended Therapy with [177Lu]Lu-PSMA: A German Multicenter Study

Prospective results have demonstrated favorable safety and efficacy of [177Lu]Lu-PSMA radiopharmaceutical therapy for up to 6 cycles in men with metastatic castration-resistant prostate cancer. However, no systematic data are available outlining the feasibility of extended therapy beyond 6 cycles. We aim to evaluate the safety and efficacy of extended [177Lu]Lu-PSMA radiopharmaceutical therapy in patients who have received more than 6 cycles. Methods: In total, 111 patients were included in this multicenter retrospective analysis. Based on individual decisions, patients underwent uninterrupted continuation of therapy (continuous treatment) or reexposure after a therapy break (rechallenge treatment) between 2014 and 2023. Overall survival, 50% prostate-specific antigen (PSA) decline (measured 8-12 wk after treatment initiation or rechallenge), PSMA PET response, and grades per Common Terminology Criteria for Adverse Events were assessed. χ2 tests, multivariable Cox regression analysis, and log-rank tests were applied for statistical analyses. Results: Patients received extended treatment with [177Lu]Lu-PSMA, either as a continuous treatment (43/111, 38.7%) or as a rechallenge (68/111, 61.3%) treatment, with median cumulative doses of 57.4 or 60.8 GBq, respectively. Overall survival from the initiation of [177Lu]Lu-PSMA was 31.3, 23.2, and 40.2 mo for the entire cohort, the continuous treatment group, and the rechallenge treatment group, respectively. The initial 50% PSA decline was significantly higher in the retreated group than in the continuous group (57/63 [90.4%] vs. 26/42 [61.9%]; P = 0.006). A 50% PSA decline was observed in 23 of 62 patients (37.1%) after the first rechallenge. The rate of grades 3-4 toxicity was comparable between continuous and rechallenge treatments (anemia, 7/43 [16.3%] vs. 13/68 [19.1%)], P = 0.6; leukocytopenia, 1/43 [2.3%] vs. 2/67 [3.0%], P = 0.3; thrombocytopenia, 3/43 [7.0%] vs. 3/68 [4.4%], P = 0.3; renal, 2/43 [4.7%] vs. 5/68 [7.4%], P = 0.2). Conclusion: Extended therapy with [177Lu]Lu-PSMA is safe and has not been associated with increased grades 3-4 toxicity. Patient candidates for extended treatment experienced a favorable median survival of 31.3 mo from the first administration. Response under [177Lu]Lu-PSMA rechallenge demonstrated preserved efficacy of [177Lu]Lu-PSMA after a treatment break.

Deep and Durable Prostate-specific Antigen Response to Darolutamide with Androgen Deprivation Therapy and Docetaxel, and Association with Clinical Outcomes for Patients with High- or Low-volume Metastatic Hormone-sensitive Prostate Cancer: Analyses of the Randomized Phase 3 ARASENS Study

BACKGROUND AND OBJECTIVE

Addition of darolutamide to androgen deprivation therapy (ADT) and docetaxel significantly improved overall survival (OS) in ARASENS (NCT02799602). Here we report on prostate-specific antigen (PSA) responses and their association with outcomes.

METHODS

ARASENS is an international, double-blind, phase 3 study in patients with metastatic hormone-sensitive prostate cancer (mHSPC) randomized to darolutamide 600 mg orally twice daily (n = 651) or placebo (n = 654), both with ADT + docetaxel. The proportion of patients with undetectable PSA (<0.2 ng/ml) and time to PSA progression (≥25% relative and ≥2 ng/ml absolute increase from nadir) were compared between groups in prespecified exploratory analyses. PSA outcomes by disease volume and the association of undetectable PSA with OS and times to castration-resistant prostate cancer (CRPC) and PSA progression were assessed in post hoc analyses.

KEY FINDINGS AND LIMITATIONS

The proportion of patients with undetectable PSA at any time was more than doubled with darolutamide versus placebo, at 67% versus 29% in the overall population, 62% versus 26% in the high-volume subgroup, and 84% versus 38% in the low-volume subgroup. Darolutamide delayed time to PSA progression versus placebo, with hazard ratios of 0.26 (95% confidence interval [CI] 0.21-0.31) in the overall population, 0.30 (95% CI 0.24-0.37) in the high-volume subgroup, and 0.093 (95% CI 0.047-0.18) in the low-volume subgroup. Undetectable PSA at 24 wk was associated with longer OS, with a hazard ratio of 0.49 (95% CI 0.37-0.65) in the darolutamide group, as well as longer times to CRPC and PSA progression, with similar findings in the disease volume subgroups.

CONCLUSIONS AND CLINICAL IMPLICATIONS

Darolutamide + ADT + docetaxel led to deep and durable PSA responses in patients with high- or low-volume mHSPC. Achievement of undetectable PSA (<0.2 ng/ml) was correlated with better clinical outcomes.

PATIENT SUMMARY

For patients with metastatic hormone-sensitive prostate cancer being treated with androgen deprivation therapy and docetaxel, PSA (prostate-specific antigen) became undetectable (below 0.2 ng/ml) in 67% of those also receiving darolutamide versus 29% of patients also receiving placebo. On average, patients achieving undetectable PSA lived longer than patients with detectable PSA.

Sunitinib for metastatic renal cell carcinoma: Real world data from the STAR-TOR registry and detailed literature review

INTRODUCTION

We evaluated the effectiveness and safety profile of the tyrosine kinase inhibitor Sunitinib in patients with advanced or metastatic renal cell carcinoma (a/mRCC) in a real-world setting.

METHODS

We analyzed data of adult a/mRCC patients treated with Sunitinib. Data was derived from the German non-interventional post-approval multicenter STAR-TOR registry (NCT00700258). Progression-free survival (PFS), overall survival (OS), and adverse events (AEs) were evaluated using descriptive statistics and survival analyses for the entire cohort and patient subgroups.

RESULTS

A total of 116 study sites recruited 702 patients treated with Sunitinib (73.1% male; median age 68.0 years; median Karnofsky Index 90%) between November 2010 and May 2020. The most frequent histological subtype was clear cell RCC (ccRCC) (81.6%). Sunitinib was administered as first-line treatment in 83.5%, as second line in 11.7%, and as third line or beyond in 4.8% of the patients. Drug related AEs and serious AEs were reported in 66.3% and 13.9% of the patients, respectively (most common AE: gastrointestinal disorders; 39.7% of all patients).

CONCLUSIONS

This study adds further real-world evidence of the persisting relevance of Sunitinib for patients with a/mRCC who cannot receive or tolerate immune checkpoint inhibitors. The study population includes a high proportion of patients with unfavorable MSKCC poor-risk score, but shows still good PFS and OS results, while the drug demonstrates a favorable safety profile.

[Emergencies in cancer immunotherapy]

BACKGROUND

Immunomodulatory therapies are becoming increasingly important in uro-oncology. For this reason, we will probably be increasingly confronted with side effects. In addition, there is an increasing number of combinations with other mechanisms of action. Immune-mediated side effects may occur as a consequence of this therapy. These are different from the side effects of chemotherapy and other targeted therapies and therefore require different treatment strategies.

AIM

Based on the current literature, the data on graduation and stage-dependent management will be presented as well as illustrated with examples from practice.

MATERIALS AND METHODS

Literature review on the detection and therapeutic management of adverse events mediated in the setting of immuno-oncologic therapy.

RESULTS

Treatment-related events can in principle affect all organ systems. Toxicities in the area of the skin, such as rash or pruritus, hypo- or hyperthyreosis, arthritis, muscle pain and gastrointestinal symptoms are frequently seen. In terms of frequency, most side effects are grade 1 to 2, but grade 3 to 4 toxicities are also generally well treatable if detected early. Rare complications such as neurological toxicities, pneumonitis or carditis can develop a fulminant course if diagnosed too late.

CONCLUSIONS

Even emergencies are manageable if we know the most important side effects and the therapeutic options. Immune-mediated side effects are of particular importance because they can affect any organ system. However, as long as we consider the possibility of toxicity from checkpoint inhibitors when the patient presents with symptoms, most side effects are easy to treat and therefore manageable.

Role of apalutamide in the treatment landscape for patients with advanced prostate cancer: an expert opinion statement of European clinical practice

BACKGROUND

Patients with advanced prostate cancer have a poor prognosis, and well-tolerated new treatment strategies are required to improve survival outcomes. Apalutamide is a novel androgen signalling inhibitor developed to be used in combination with continuous androgen deprivation therapy (ADT) for the treatment of patients with advanced prostate cancer. Based on evidence from two phase 3 pivotal clinical trials in non-metastatic castration-resistant (nmCRPC; SPARTAN) and metastatic hormone-sensitive prostate cancer (mHSPC; TITAN), ADT plus apalutamide significantly extends overall survival compared with the standard of care.

AIMS

To provide practical recommendations to guide optimal use in the real-world setting as the use of apalutamide in clinical practice increases.

METHODS

Expert opinion from a group of European physicians is presented here to educate on the use of apalutamide in combination with ADT in patients with mHSPC and patients with nmCRPC who are at risk of developing metastatic disease, focusing on practical considerations such as patient selection, monitoring, and management of side effects.

RESULTS

In clinical practice, apalutamide in combination with ADT can be used in a broad patient population including patients with high and low volume/risk mHSPC, patients with de novo metastatic disease or metastases following treatment for localised disease, as well as older patients. Apalutamide in combination with ADT is well tolerated, with manageable side effects which do not impact health-related quality of life compared to ADT alone.

CONCLUSIONS

Real-world experience with apalutamide supports the efficacy and safety findings reported by the SPARTAN and TITAN clinical trials.

Darolutamide Plus Androgen-Deprivation Therapy and Docetaxel in Metastatic Hormone-Sensitive Prostate Cancer by Disease Volume and Risk Subgroups in the Phase III ARASENS Trial

PURPOSE

For patients with metastatic hormone-sensitive prostate cancer, metastatic burden affects outcome. We examined efficacy and safety from the ARASENS trial for subgroups by disease volume and risk.

METHODS

Patients with metastatic hormone-sensitive prostate cancer were randomly assigned to darolutamide or placebo plus androgen-deprivation therapy and docetaxel. High-volume disease was defined as visceral metastases and/or ≥ 4 bone metastases with ≥ 1 beyond the vertebral column/pelvis. High-risk disease was defined as ≥ 2 risk factors: Gleason score ≥ 8, ≥ 3 bone lesions, and presence of measurable visceral metastases.

RESULTS

Of 1,305 patients, 1,005 (77%) had high-volume disease and 912 (70%) had high-risk disease. Darolutamide increased overall survival (OS) versus placebo in patients with high-volume (hazard ratio [HR], 0.69; 95% CI, 0.57 to 0.82), high-risk (HR, 0.71; 95% CI, 0.58 to 0.86), and low-risk disease (HR, 0.62; 95% CI, 0.42 to 0.90), and in the smaller low-volume subgroup, the results were also suggestive of survival benefit (HR, 0.68; 95% CI, 0.41 to 1.13). Darolutamide improved clinically relevant secondary end points of time to castration-resistant prostate cancer and subsequent systemic antineoplastic therapy versus placebo in all disease volume and risk subgroups. Adverse events (AEs) were similar between treatment groups across subgroups. Grade 3 or 4 AEs occurred in 64.9% of darolutamide patients versus 64.2% of placebo patients in the high-volume subgroup and 70.1% versus 61.1% in the low-volume subgroup. Among the most common AEs, many were known toxicities related to docetaxel.

CONCLUSION

In patients with high-volume and high-risk/low-risk metastatic hormone-sensitive prostate cancer, treatment intensification with darolutamide, androgen-deprivation therapy, and docetaxel increased OS with a similar AE profile in the subgroups, consistent with the overall population.[Media: see text].

A Prognostic Risk Score for Prostate Cancer Based on PSMA PET-derived Organ-specific Tumor Volumes

Background Prostate-specific membrane antigen (PSMA) PET has high specificity in localizing primary tumors and metastases in patients with prostate cancer, but the individual overall survival probability is still difficult to estimate. Purpose To develop a prognostic risk score using PSMA PET-derived organ-specific total tumor volumes for predicting overall survival in patients with prostate cancer. Materials and Methods Men with prostate cancer who underwent PSMA PET/CT from January 2014 to December 2018 were evaluated retrospectively. All patients from center A were split into training (80%) and internal validation (20%) cohorts. Randomly selected patients from center B were used for external validation. Organ-specific tumor volumes were automatically quantified from PSMA PET scans by a neural network. A prognostic score was selected using multivariable Cox regression guided by the Akaike information criterion (AIC). The final prognostic risk score fitted on the training set was applied to both validation cohorts. Results A total of 1348 men (mean age, 70 years ± 8 [SD]) were included, with 918 patients in the training cohort, 230 in the internal validation cohort, and 200 in the external validation cohort. The median follow-up time was 55.7 months (IQR, 46.7-65.1 months; >4 years; 429 deaths occurred). A body weight-adjusted prognostic risk score integrating total, bone, and visceral tumor volumes obtained high C index values in the internal (0.82) and external (0.74) validation cohorts, as well as in patients with castration-resistant (0.75) and hormone-sensitive (0.68) disease. The fit of the statistical model for the prognostic score was improved compared with a model containing total tumor volume only (AIC, 3324 vs 3351; likelihood ratio test, P < .001). Calibration plots ascertained good model fit. Conclusion The newly developed risk score that included prostate-specific membrane antigen PET-derived organ-specific tumor volumes had good model fit for predicting overall survival in both internal and external validation cohorts. Published under a CC BY 4.0 license. Supplemental material is available for this article. See also the editorial by Civelek in this issue.

Co-expression and clinical utility of AR-FL and AR splice variants AR-V3, AR-V7 and AR-V9 in prostate cancer

BACKGROUND

Androgen receptor (AR) splice variants (AR-Vs) have been discussed as a biomarker in prostate cancer (PC). However, some reports question the predictive property of AR-Vs. From a mechanistic perspective, the connection between AR full length (AR-FL) and AR-Vs is not fully understood. Here, we aimed to investigate the dependence of AR-FL and AR-V expression levels on AR gene activity. Additionally, we intended to comprehensively analyze presence of AR-FL and three clinically relevant AR-Vs (AR-V3, AR-V7 and AR-V9) in different stages of disease, especially with respect to clinical utility in PC patients undergoing AR targeted agent (ARTA) treatment.

METHODS

AR-FL and AR-V levels were analyzed in PC and non-PC cell lines upon artificial increase of AR pre-mRNA using either drug treatment or AR gene activation. Furthermore, expression of AR-FL and AR-Vs was determined in PC specimen at distinct stages of disease (primary (n = 10) and metastatic tissues (n = 20), liquid biopsy samples (n = 422), mCRPC liquid biopsy samples of n = 96 patients starting novel treatment). Finally, baseline AR-FL and AR-V status was correlated with clinical outcome in a defined cohort of n = 65 mCRPC patients undergoing ARTA treatment.

RESULTS

We revealed rising levels of AR-FL accompanied with appearance and increase of AR-Vs in dependence of elevated AR pre-mRNA levels. We also noticed increase in AR-FL and AR-V levels throughout disease progression. AR-V expression was always associated with high AR-FL levels without any sample being solely AR-V positive. In patients undergoing ARTA treatment, AR-FL did show prognostic, yet not predictive validity. Additionally, we observed a substantial clinical response to ARTA treatment even in AR-V positive patients. Accordingly, multivariate analysis did not demonstrate independent significance of AR-Vs in neither predictive nor prognostic clinical utility.

CONCLUSION

We demonstrate a correlation between AR-FL and AR-V expression during PC progression; with AR-V expression being a side-effect of elevated AR pre-mRNA levels. Clinically, AR-V positivity relies on high levels of AR-FL, making cells still vulnerable to ARTA treatment, as demonstrated by AR-FL and AR-V positive patients responding to ARTA treatment. Thus, AR-FL and AR-V might be considered as a prognostic, yet not predictive biomarker in mCRPC patients.

Efficacy and Safety of Darolutamide in Patients with Nonmetastatic Castration-resistant Prostate Cancer Stratified by Prostate-specific Antigen Doubling Time: Planned Subgroup Analysis of the Phase 3 ARAMIS Trial

BACKGROUND

Patients with nonmetastatic castration-resistant prostate cancer (nmCRPC) have a high risk of progression to metastatic disease, particularly if their prostate-specific antigen doubling time (PSADT) is ≤6 mo. However, patients remain at a high risk with a PSADT of >6 mo.

OBJECTIVE

To evaluate the efficacy and safety of darolutamide versus placebo in patients stratified by PSADT >6 or ≤6 mo.

DESIGN, SETTING, AND PARTICIPANTS

A planned subgroup analysis of a global multicenter, double-blind, randomized, phase 3 trial in men with nmCRPC and PSADT ≤10 mo was conducted.

INTERVENTION

Patients were randomized 2:1 to oral darolutamide 600 mg twice daily or placebo, while continuing androgen-deprivation therapy.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

The primary endpoint was metastasis-free survival (MFS). Secondary endpoints were overall survival (OS) and times to pain progression, first cytotoxic chemotherapy, and symptomatic skeletal events. Quality of life (QoL) was measured using validated prostate-relevant tools. Safety was recorded throughout the study.

RESULTS AND LIMITATIONS

Of 1509 patients enrolled, 469 had PSADT >6 mo (darolutamide n = 286; placebo n = 183) and 1040 had PSADT ≤6 mo (darolutamide n = 669; placebo n = 371). Baseline characteristics were balanced between subgroups. Darolutamide significantly prolonged MFS versus placebo in both subgroups (unstratified hazard ratio [95% confidence interval]: PSADT >6 mo, 0.38 [0.26-0.55]; PSADT ≤6 mo, 0.41 [0.33-0.52]). OS and other efficacy and QoL endpoints favored darolutamide with significant improvement over placebo in both subgroups. The incidence of adverse events, including events commonly associated with androgen receptor inhibitors (fractures, falls, hypertension, and mental impairment), and discontinuations due to adverse events were low and similar to placebo. Limitations include small subgroup populations.

CONCLUSIONS

In patients with nmCRPC and PSADT >6 mo (maximum 10 mo), darolutamide provided a favorable benefit/risk ratio, characterized by significant improvements in MFS, OS, and other clinically relevant endpoints; maintenance of QoL; and favorable tolerability.

PATIENT SUMMARY

In patients with prostate cancer that has stopped responding to standard hormonal therapy (indicated by an increase in prostate-specific antigen [PSA] levels), there is a risk that the cancer will spread to other parts of the body. This risk is highest when the time it takes for the PSA level to double (ie, "PSA doubling time" [PSADT]) is less than 6 mo. However, there is still a risk that the cancer will spread even if the PSADT is longer than 6 mo. In a group of patients whose PSADT was more than 6 mo but no more than 10 mo, treatment with darolutamide slowed the cancer spread and allowed them to live longer than patients who received placebo (inactive drug). Darolutamide treatment did not cause many side effects and helped maintain patients' quality of life without disruptions.

The Non-Interventional PAZOREAL Study to Assess the Effectiveness and Safety of Pazopanib in a Real-Life Setting: Reflecting a Changing mRCC Treatment Landscape

The approval of tyrosine kinase inhibitors and checkpoint inhibitors represented a remarkable progression in the therapeutic landscape for the treatment of metastatic renal cell carcinoma (mRCC). Yet, in the ever-evolving landscape of mRCC treatment, real-world data on these agents, including pazopanib, are scarce. The non-interventional PAZOREAL study investigated the effectiveness and safety of pazopanib (first-line), nivolumab (second-line), and everolimus (second- and third-line) in a real-life setting. The multicentric study included 376 mRCC patients who received first-line treatment with pazopanib and assessed time on the drug (primary endpoint), overall survival, best responses, disease control rates, as well as safety signals and health-related quality of life. The median overall time on the drug was 10.0 months, with first-line pazopanib having a median time on drug of 6.3 months. The median overall survival was 35.9 months. The disease control rate for first-line pazopanib was 56.9%. No new safety signals were detected. PAZOREAL provides valuable real-world data for first-line treatment with pazopanib.

Time after Synthesis and Time after Injection Do Not Affect Diagnostic Quality of [18F]F-PSMA 1007 PET

Simple Summary

The total number of PSMA-PET-CT examinations for the staging of prostate cancer patients has increased in recent years, following its superior imaging properties. Fluorinated PSMA ligands can be produced in larger amounts, facilitating higher patient throughput compared to the initially developed gallium labelled PSMA-tracers; allowing PET in only a few patients per synthesis. This results in a longer time after, typically early morning, radiochemical synthesis (TaS) of [¹⁸]F-PSMA when the PSMA-PET scan is performed. Moreover, novel fluorinated-PSMA compounds are injected around two hours before PET-CT and the time after injection (TaI) might show significant deviation. [18F]-PSMA PET offers improved detection rates in the proximity of the urinary tract; however, it has the disadvantage of more unspecific uptake, e.g., in the skeleton. This article focusses on the question whether TaS or TaI have an influence on uptake patterns in malignant lesions and healthy tissue.

Abstract

PET imaging using PSMA ligands is increasingly used for staging in prostate cancer patients in different clinical indications. Unlike [⁶⁸Ga]Ga-labeled PSMA ligands, fluorinated compounds can be produced in large amounts; thus, they can be used for a higher number of patients. One concern is that in patients studied a long time after synthesis (TaS) or time after injection (TaI), the specific activity may decline; thus, the signal may be lower in these patients. In this study, we investigated a potential effect of TaS and TaI on image quality. In total, 134 consecutive patients were included in this retrospective analysis on the effect of TaS and TaI on uptake in prostate cancer lesions. All the patients underwent [¹⁸F]F-PSMA-1007 PET-CT from 99 min up to 549 min after tracer quality control. TaS and TaI were compared to the quantitative tumoral uptake parameters SUVmax and SUVpeak. In a second exploratory part of the analysis, TaS and TaI were correlated to a physiological tracer uptake in different organs. TaS and TaI did not affect the SUVmax and SUVpeak in tumor lesions in [¹⁸F]F-PSMA-1007 PET. The physiological uptake in salivary glands, lacrimal glands and the ganglia, spleen and urine was not significantly correlated to TaS or TaI; in contrast to the mean liver uptake, showing a weak, but significant correlation to TaS. The [¹⁸F]F-PSMA-1007 uptake in prostate cancer lesions is not significantly dependent on the TaS and TaI. These results are extremely reassuring when performing [¹⁸F]F-PSMA-1007 PET a considerable time after synthesis.

Real-World Data on the Use of Nivolumab Monotherapy in the Treatment of Advanced Renal Cell Carcinoma after Prior Therapy: Interim Results from the Noninterventional NORA Study

BACKGROUND

Nivolumab monotherapy is approved for the treatment of advanced renal cell carcinoma (aRCC) after prior therapy on the basis of results from CheckMate 025.

OBJECTIVE

The NORA (NivOlumab in Renal cell cArcinoma) noninterventional study (NIS) aims to capture real-world data to complement the pivotal CheckMate 025 clinical trial.

DESIGN, SETTING, AND PARTICIPANTS

NORA is a prospective, multicenter NIS in Germany. Consenting patients with aRCC of any subtype who started nivolumab after previous therapy were eligible.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

The primary objective was to estimate overall survival (OS) in the overall population and relevant subgroups. Secondary objectives included progression-free survival (PFS), the objective response rate (ORR), the duration of response (DOR), safety, and patient-reported outcomes (PROs). Baseline characteristics were summarized using descriptive statistics. OS and PFS were estimated via the Kaplan-Meier-method.

RESULTS AND LIMITATIONS

A total of 228 patients with aRCC were eligible. The median age was 70 yr, 71% were male, 14% had favorable, 58% had intermediate, and 15% had poor International Metastatic RCC Database Consortium risk (12% missing information). The median follow-up was 37 mo. In the overall population, median OS was 24 mo (95% confidence interval [CI] 19-28) and median PFS was 5.3 mo (95% CI 3.9-6.7). The ORR was 20% and the median DOR was 28 mo (95% CI 16-not estimable). No new safety signals emerged (46% and 15% of patients had treatment-related adverse events of all grades and grade 3-4, respectively; there was 1 treatment-related death due to liver failure). PROs did not reveal detriments during the study duration. Limitations include the lack of central pathology review and no standardization for imaging evaluation and toxicity assessment.

CONCLUSIONS

Effectiveness and safety in this real-world population were in line with the pivotal clinical trial and support the use of nivolumab after prior systemic therapy in a broad aRCC population.

PATIENT SUMMARY

Nivolumab is an antibody treatment approved for patients with advanced kidney cancer who have already received systemic therapy. Its approval was based on results from a clinical trial. Our study demonstrates its effectiveness and safety in "real-world" patients.

Pembrolizumab Plus Docetaxel and Prednisone in Patients with Metastatic Castration-resistant Prostate Cancer: Long-term Results from the Phase 1b/2 KEYNOTE-365 Cohort B Study

BACKGROUND

Patients with metastatic castration-resistant prostate cancer (mCRPC) frequently receive docetaxel after they develop resistance to abiraterone or enzalutamide and need more efficacious treatments.

OBJECTIVE

To evaluate the efficacy and safety of pembrolizumab plus docetaxel and prednisone in patients with mCRPC.

DESIGN, SETTING, AND PARTICIPANTS

The trial included patients with mCRPC in the phase 1b/2 KEYNOTE-365 cohort B study who were chemotherapy naïve and who experienced failure of or were intolerant to ≥4 wk of abiraterone or enzalutamide for mCRPC with progressive disease within 6 mo of screening.

INTERVENTION

Pembrolizumab 200 mg intravenously (IV) every 3 wk (Q3W), docetaxel 75 mg/m² IV Q3W, and prednisone 5 mg orally twice daily.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

The primary endpoints were safety, the prostate-specific antigen (PSA) response rate, and the objective response rate (ORR) according to Response Evaluation Criteria in Solid Tumors version 1.1 (RECIST v1.1) by blinded independent central review (BICR). Secondary endpoints included time to PSA progression; the disease control rate (DCR) and duration of response (DOR) according to RECIST v1.1 by BICR; ORR, DCR, DOR, and radiographic progression-free survival (rPFS) according to Prostate Cancer Working Group 3-modified RECIST v1.1 by BICR; and overall survival (OS).

RESULTS AND LIMITATIONS

Among 104 treated patients, 52 had measurable disease. The median time from allocation to data cutoff (July 9, 2020) was 32.4 mo, during which 101 patients discontinued treatment, 81 (78%) for disease progression. The confirmed PSA response rate was 34% and the confirmed ORR (RECIST v1.1) was 23%. Median rPFS and OS were 8.5 mo and 20.2 mo, respectively. Treatment-related adverse events (TRAEs) occurred in 100 patients (96%). Grade 3-5 TRAEs occurred in 46 patients (44%). Seven AE-related deaths (6.7%) occurred (2 due to treatment-related pneumonitis). Limitations of the study include the single-arm design and small sample size.

CONCLUSIONS

Pembrolizumab plus docetaxel and prednisone demonstrated antitumor activity in chemotherapy-naïve patients with mCRPC treated with abiraterone or enzalutamide for mCRPC. Safety was consistent with profiles for the individual agents. Further investigation is warranted.

PATIENT SUMMARY

We evaluated the efficacy and safety of the anti-PD-1 antibody pembrolizumab combined with the chemotherapy drug docetaxel and the steroid prednisone for patients with metastatic prostate cancer resistant to androgen deprivation therapy , and who never received chemotherapy. The combination showed antitumor activity and manageable safety in this patient population. This trial is registered on ClinicalTrials.gov as NCT02861573.

[Non-metastatic castration-resistant prostate cancer (M0CRPC) - Apalutamide in high-risk M0CRPC: case reports from the SPARTAN study and the apalutamide compassionate use program]

The occurrence of distant metastases represents a prognostically unfavourable turning point in non-metastatic castration-resistant prostate cancer (M0CRPC). M0CRPC patients with a short PSA doubling time have a particularly high risk of progression. For a long time, there was no further treatment option for these patients apart from watchful waiting while maintaining classic androgen deprivation therapy (ADT). Apalutamide, a next-generation anti-androgen available since January 2019, significantly increased metastasis-free survival compared with placebo in the pivotal SPARTAN trial in patients with high-risk M0CRPC. The presented patient cases from SPARTAN and the apalutamide compassionate use program are examples of the beneficial effects that apalutamide can achieve in the M0CRPC setting.

Does the Identification of a Minimum Number of Cases Correlate With Better Adherence to International Guidelines Regarding the Treatment of Penile Cancer? Survey Results of the European PROspective Penile Cancer Study (E-PROPS)

Background

Penile cancer represents a rare malignant disease, whereby a small caseload is associated with the risk of inadequate treatment expertise. Thus, we hypothesized that strict guideline adherence might be considered a potential surrogate for treatment quality. This study investigated the influence of the annual hospital caseload on guideline adherence regarding treatment recommendations for penile cancer.

Methods

In a 2018 survey study, 681 urologists from 45 hospitals in four European countries were queried about six hypothetical case scenarios (CS): local treatment of the primary tumor pTis (CS1) and pT1b (CS2); lymph node surgery inguinal (CS3) and pelvic (CS4); and chemotherapy neoadjuvant (CS5) and adjuvant (CS6). Only the responses from 206 head and senior physicians, as decision makers, were evaluated. The answers were assessed based on the applicable European Association of Urology (EAU) guidelines regarding their correctness. The real hospital caseload was analyzed based on multivariate logistic regression models regarding its effect on guideline adherence.

Results

The median annual hospital caseload was 6 (interquartile range (IQR) 3–9). Recommendations for CS1–6 were correct in 79%, 66%, 39%, 27%, 28%, and 28%, respectively. The probability of a guideline-adherent recommendation increased with each patient treated per year in a clinic for CS1, CS2, CS3, and CS6 by 16%, 7.8%, 7.2%, and 9.5%, respectively (each p < 0.05); CS4 and CS5 were not influenced by caseload. A caseload threshold with a higher guideline adherence for all endpoints could not be perceived. The type of hospital care (academic vs. non-academic) did not affect guideline adherence in any scenario.

Conclusions

Guideline adherence for most treatment recommendations increases with growing annual penile cancer caseload. Thus, the results of our study call for a stronger centralization of diagnosis and treatment strategies regarding penile cancer.

Evaluation of 68Ga-PSMA-11 PET-MRI in Patients with Advanced Prostate Cancer Receiving 177Lu-PSMA-617 Therapy: A Radiomics Analysis

¹⁷⁷Lutetium PSMA-617 (Lu-PSMA) therapy in patients with metastatic castration resistant prostate cancer (mCRPC) has gained visibility through the ongoing phase III trial. The data on prediction of therapy outcome and survival out of pretherapeutic imaging parameters is still sparse. In this study, the predictive and prognostic value of radiomic features from ⁶⁸Ga-PSMA-11 PET-MRI are analyzed. In total, 21 patients with mCRPC underwent ⁶⁸Ga-PSMA-11 PET-MRI before Lu-PSMA therapy. The PET-positive tumor volume was defined and transferred to whole-body T2-, T1- and contrast-enhanced T1-weighted MRI-sequences. The radiomic features from PET and MRI sequences were extracted by using a freely available software package. For selecting features that allow differentiation of biochemical response (PSA decrease > 50%), a stepwise dimension reduction was performed. Logistic regression models were fitted, and selected features were tested for their prognostic value (overall survival) in all patients. Eight patients achieved biochemical response after Lu-PSMA therapy. Ten independent radiomic features differentiated well between responders and non-responders. The logistic regression model, including the feature interquartile range from T2-weighted images, revealed the highest accuracy (AUC = 0.83) for the prediction of biochemical response after Lu-PSMA therapy. Within the final model, patients with a biochemical response (p = 0.003) and higher T2 interquartile range values in pre-therapeutic imaging (p = 0.038) survived significantly longer. This proof-of-concept study provides first evidence on a potential predictive and prognostic value of radiomic analysis of pretherapeutic ⁶⁸Ga-PSMA-11 PET-MRI before Lu-PSMA therapy.

Total tumor volume reduction and low PSMA expression in patients receiving Lu-PSMA therapy

Background: [¹⁷⁷Lu]-PSMA-617 (Lu-PSMA) therapy is a promising therapeutic option for end-stage prostate cancer patients. Early treatment response at the first restaging after two therapy cycles might correlate with high treatment efficacy and long overall survival (OS). Therefore, the aim of this study was to evaluate whether early reduction in tumor volume is a positive prognosticator for OS. To this end, PSMA PET prior to therapy (baseline) and at first restaging after two therapy cycles (interim; i.e., 12 weeks) were compared.

Methods: Patients with metastatic castration-resistant prostate cancer who received Lu-PSMA therapy were reviewed for this analysis. All patients with available baseline and interim [⁶⁸Ga]-PSMA-11 PET/CT were included in this analysis (n = 33). All PSMA avid metastases in baseline and interim PETs were semi-automatically segmented. The average PSMA expression (mean SUV_max of all metastases), total tumor volume (PSMA-TV) and TLQ (quotients of tumor volume and SUV_mean summed over all metastases) were quantified at baseline and interim timepoints. Response in PSMA-TV was assumed when a decline > 30% was present. OS and biochemical response were available for all patients.

Results: Baseline PSMA-TV was a statistically significant prognosticator of OS (HR = 1.618 95%CI: 1.117 - 2.343, p = 0.011). Reduction in PSMA-TV was not a statistically significant positive prognosticator of OS in the total cohort (HR = 0.829 95%CI: 0.559 - 1.230, p = 0.352). Likewise, there was no statistical difference in survival time comparing patients with PSMA-TV response to those without (13.2 vs. 15.6 months, p = 0.1). In the subgroup of patients with PSMA-TV response, mean SUV_max was a statistically significant prognosticator of OS (binarized by median; HR = 0.15; 95%CI: 0.03 - 0.83; p < 0.05). If patients with low PSMA expression at baseline were excluded from the analysis, reduction in PSMA-TV became a positive prognosticator of OS in uni- and multivariable Cox regression (HR = 0.290; 95%CI: 0.108 - 0.782; p = 0.015).

Conclusion: PSMA-TV reduction was a positive prognosticator of OS only if patients with low PSMA expression were excluded. This might indicate that the PSMA-PETs of patients with low PSMA expression may not be suited for assessing PSMA-TV reduction. Future studies investigating the interplay of PSMA-TV and low PSMA expression response are warranted.

Lutetium-177-prostate-specific membrane antigen ligand following radium-223 treatment in men with bone-metastatic castration-resistant prostate cancer: real-world clinical experience

We analyzed real-world clinical outcomes of sequential α-/β-emitter therapy for metastatic castration-resistant prostate cancer (mCRPC). Methods: We assessed safety and overall survival in 26 patients who received ¹⁷⁷Lu-prostate-specific membrane antigen ligand (¹⁷⁷Lu-PSMA) after ²²³Ra in the ongoing noninterventional REASSURE study (²²³Ra α-Emitter Agent in Nonintervention Safety Study in mCRPC Population for Long-Term Evaluation; NCT02141438). Results: Patients received ²²³Ra for a median of 6 injections and subsequent ¹⁷⁷Lu-PSMA for a median of 3.5 mo (≥ the fourth therapy in 69%). The median time between ²²³Ra and ¹⁷⁷Lu-PSMA treatment was 8 mo (range, 1–31 mo). Grade 3 hematologic events occurred in 9 of 26 patients (during or after ¹⁷⁷Lu-PSMA treatment in 5/9 patients; 8/9 patients had also received docetaxel). Median overall survival was 28.0 mo from the ²²³Ra start and 13.2 mo from the ¹⁷⁷Lu-PSMA start. Conclusion: Although the small sample size precludes definitive conclusions, these preliminary data, especially the ¹⁷⁷Lu-PSMA treatment duration, suggest that the use of ¹⁷⁷Lu-PSMA after ²²³Ra is feasible in this real-world setting.

The impact of the extent of the bone involvement on overall survival and toxicity in mCRPC patients receiving [177Lu]Lu-PSMA-617: a WARMTH multicentre study

INTRODUCTION

Prostate-specific membrane antigen (PSMA)-based radioligand therapy (RLT) showed in a multicentre WARMTH (World Association of Radiopharmaceutical and Molecular Therapy) study that the presence of bone metastases is a negative prognosticator for the survival. The current multicentre retrospective analysis aims to evaluate the response rate to RLT, the overall survival (OS) of patients and the safety of the treatment according to the extent of bone involvement.

METHODS

The study included patients with progressive metastatic castration-resistant prostate cancer (mCRPC), who underwent RLT with [¹⁷⁷Lu]Lu-PSMA-617 and a follow-up of at least 6 months. Tumour burden in the bone was classified prior to RLT as follows: less than 6 lesions, 6-20 lesions, more than 20 lesions and diffuse involvement. The response rate was evaluated using changes of the prostate-specific antigen (PSA) after the first treatment cycle. Overall survival was calculated from the date of the first treatment. Haematological adverse events were classified according to Common Terminology Criteria for Adverse Events (CTCAE), version 5.0.

RESULTS

A total of 319 males were included in the analysis. The extent of bone metastases and PSA response did not correlate significantly. Any PSA decline was observed in 73% patients; 44% showed a decline of ≥50%. The median OS of patient in the different subgroups was 18 months (less than 6 lesions), 13 months (6-20 lesions), 11 months (more than 20 lesions) and 8 months (diffuse involvement), respectively (p < 0.0001). Patients with prior Ra-223-therapy showed longer OS in all subgroups, especially in the subgroups with 6-20 lesions (OS: 16 vs. 12 months; p = 0.038) as well as diffuse involvement (OS: 11 vs. 7 months; p = 0.034). Significant negative prognosticators of OS were the existence of liver metastases in all subgroups and prior chemotherapy in patients with <6 bone lesions. Anaemia and thrombocytopenia correlated positively with the extent of bone metastases: p < 0.0001 and 0.005, respectively. No patient showed a high grade leukopenia.

CONCLUSION

The extent of bone involvement correlated negatively with the OS after RLT; however, it showed no relevant correlation with the PSA response rate. Prior therapy with Ra-223 may have a positive impact on OS. Haematotoxicity was higher in patients with more than 20 bone lesions; nevertheless, the majority of these patients did not show a relevant haematotoxicity.

[Apalutamide in patients with high-risk M0CRPC: data from the pivotal SPARTAN study and initial experience from a compassionate use program]

Non-metastatic castration-resistant prostate carcinoma (M0CRPC) is associated with an increased risk of progression and mortality, especially if the prostate-specific antigen doubling time is short (PSADT ≤ 10 months). The risk of progression and mortality increases even further if the disease progresses to the metastatic stage (mCRPC). The androgen receptor inhibitors apalutamide, darolutamide and enzalutamide, each in combination with androgen deprivation therapy (ADT), are available for the treatment of patients with high-risk M0CRPC.Data from the pivotal SPARTAN study showed that apalutamide + ADT delayed metastasis-free survival (MFS) and thus also the development of mCRPC in these patients. Prior to the approval of apalutamide in the European Union, the active substance was available in Germany as part of an international compassionate use program. A total of 109 patients from 50 centres participated in Germany: 45 patients were treated for more than 3 months and 13 patients for more than 6 months. The compassionate use program continues in some countries; 556 patients have been enrolled worldwide.In our experience, this real-world population showed a good PSA response, which was also shown for this exploratory endpoint in the SPARTAN study. We were also unable to identify any significant differences from the pivotal trial with regards to the tolerability profile.Apalutamide in combination with ADT was also effective in this real-world population and led to a rapid decrease in PSA. The tolerability profile did not differ from that in the SPARTAN trial.

Treatment of nonmetastatic castration-resistant prostate cancer: focus on second-generation androgen receptor inhibitors

BACKGROUND

Nonmetastatic castration-resistant prostate cancer (nmCRPC) is defined as a rising prostate-specific antigen concentration, despite castrate levels of testosterone with ongoing androgen-deprivation therapy or orchiectomy, and no detectable metastases by conventional imaging. Patients with nmCRPC progress to metastatic disease and are at risk of developing cancer-related symptoms and morbidity, eventually dying of their disease. While patients with nmCRPC are generally asymptomatic from their disease, they are often older and have chronic comorbidities that require long-term concomitant medication. Therefore, careful consideration of the benefit-risk profile of potential treatments is required.

METHODS

In this review, we will discuss the rationale for early treatment of patients with nmCRPC to delay metastatic progression and prolong survival, as well as the factors influencing this treatment decision. We will focus on oral pharmacotherapy with the second-generation androgen receptor inhibitors, apalutamide, enzalutamide, and darolutamide, and the importance of balancing the clinical benefit they offer with potential adverse events and the consequential impact on quality of life, physical capacity, and cognitive function.

RESULTS AND CONCLUSIONS

While the definition of nmCRPC is well established, the advent of next-generation imaging techniques capable of detecting hitherto undetectable oligometastatic disease in patients with nmCRPC has fostered debate on the criteria that inform the management of these patients. However, despite these developments, published consensus statements have maintained that the absence of metastases on conventional imaging suffices to guide such therapeutic decisions. In addition, the prolonged metastasis-free survival and recently reported positive overall survival outcomes of the three second-generation androgen receptor inhibitors have provided further evidence for the early use of these agents in patients with nmCRPC in order to delay metastases and prolong survival. Here, we discuss the benefit-risk profiles of apalutamide, enzalutamide, and darolutamide based on the data available from their pivotal clinical trials in patients with nmCRPC.

Prostate-specific Membrane Antigen-based Imaging of Castration-resistant Prostate Cancer

CONTEXT

Positron emission tomography (PET) targeting prostate-specific membrane antigen (PSMA) has unprecedented accuracy for localization of initial or recurrent prostate cancer (PC). There is now growing evidence regarding the value of PSMA-PET in patients with advanced PC.

OBJECTIVE

To review the value of PSMA-PET/computed tomography (CT) in the context of castration-resistant PC (CRPC).

EVIDENCE ACQUISITION

A search of the PubMed database using the terms "PSMA PET castration resistant prostate cancer" (years 2011-2020) was performed. Reviews, case reports/series, non-English articles, preclinical studies, access-restricted studies, and studies on PSMA radioligand therapy without further analysis of PSMA-PET parameters were subsequently excluded.

EVIDENCE SYNTHESIS

Compared to conventional imaging, PSMA-PET better identifies the true extent of CRPC, especially nonmetastatic CRPC. The clinical benefit of this stage migration is still unclear and needs to be evaluated in further studies. High accuracy of PSMA-PET holds promise for better, PET-guided metastasis-directed treatment in patients with oligometastatic CRPC. PSMA-PET is an essential eligibility criterion for [¹⁷⁷Lu]-PSMA theranostic applications. Preliminary evidence indicates the value of PSMA-PET for the assessment of treatment responses.

CONCLUSIONS

Among other applications, PSMA-PET offers more precise staging for nonmetastatic CRPC. In particular, target localization for metastasis-directed therapy and target expression assessment for PSMA radioligand therapy also hold promise. Potential translation of this diagnostic tool into an oncologic benefit needs to be defined in future trials.

PATIENT SUMMARY

This review describes how prostate-specific membrane antigen positron emission tomography (PSMA-PET), a new sensitive imaging tool for prostate cancer, might help to guide clinicians in making treatment decisions for advanced prostate cancer.

Do fasting or high caloric drinks affect the physiological uptake of fluorine-18 prostate-specific membrane antigen-1007 in liver and bowel?

Recently introduced fluorine-18 prostate-specific membrane antigen-1007 (¹⁸F-PSMA-1007) for imaging prostate cancer has an intense physiologic liver uptake and biliary excretion. The aim of the present study was to evaluate the effect of different dietary conditions on this physiological uptake. Forty consecutive prostate cancer patients were scanned with ¹⁸F-PSMA-1007 positron emission tomography/computed tomography at different dietary conditions. In addition to a blinded read scoring, tracer uptake intensities (standardized uptake values [SUVs]) were measured in the liver and small bowel. There was no significant difference in liver and small-bowel uptake between different patient groups. Wilcoxon signed-rank tests revealed no significant difference of the median mean SUV of the liver or maximum SUV of the horizontal part of the duodenum between different dietary conditions groups. A dietary preparation of patients by fasting or the attempt to clear liver activity by high caloric drinks does not have a significant effect on tracer uptake in the liver or in the small bowel.

[Early- vs. late-onset treatment using abiraterone acetate plus prednisone in chemo-naïve, asymptomatic or mildly symptomatic patients with metastatic CRPC after androgen deprivation therapy]

BACKGROUND

 Abiraterone acetate (AA) is a prodrug of abiraterone, which is an irreversible inhibitor of 17α-hydroxylase/C17, 20-lyase. Since 2011, abiraterone acetate has been available in combination with prednisone/prednisolone (AA + P) for the treatment of metastatic castration-resistant prostate cancer (mCRPC) after pre-treatment with docetaxel, and since 2012 for the treatment of chemotherapy-naïve asymptomatic or mildly symptomatic mCRPC patients. A revision of the guidelines of the European Association of Urology in 2014 redefining castration resistance gave rise to the question of when the treatment of mCRPC with abiraterone acetate plus prednisone should be initiated after prior hormone treatment and how successful it would be. This led us to observe an early-onset AA + P therapy cohort (EC) and a late-onset therapy cohort (LC) of patients.

PATIENTS AND METHODS

 We designed a combined retrospective and prospective, multicentre, non-interventional two-cohort study to obtain data on the effectiveness and safety of an early-onset AA + P therapy in mCRPC patients in the clinical routine compared to a late therapy onset. The EC comprised patients who received AA + P immediately after castration resistance without a prior first-generation antiandrogen such as bicalutamide or flutamide. The LC included patients who, after castration resistance had occurred, started treatment with AA + P only after unsuccessful treatment with a first-generation antiandrogen. Patients with mCRPC who received AA + P therapy according to the physician's routine clinical practice decision were considered. The patients were consecutively included in the study on the basis of their medical records, with the treatment decision having been made independently of and before patient enrolment. Patients were documented or followed from the beginning of AA + P therapy until the start of a carcinoma-specific systemic follow-up therapy (retrospectively if before and prospectively if after start of data collection). Effectiveness analyses were done for all patients with at least two AA + P administrations and safety analyses for all treated patients.

RESULTS

 Of the 159 patients included, 44 received early therapy and 105 received later therapy with AA + P. 10 patients could not be clearly assigned and were summarised in a third cohort (missed early-onset therapy assignment; MEC). 56/159 patients (35.2 %) were still alive at study start and 103/159 patients (64.8 %) had already deceased (31/44 [70.5 %] in EC, 64/105 [61.0 %] in LC, and 8/10 [80.0 %] in MEC). 24/159 patients (15.1 %) were documented both retrospectively and prospectively. The median duration of AA + P treatment was 11.3 months for EC, 12.0 months for LC, and 8.3 months for MEC patients. The median time to next systemic cancer therapy or death was 12.3 months for EC and 12.8 months for LC patients (p = 0.2820). The median time to the next systemic cancer therapy alone (i. e. without the event 'death') was 22.7 months for EC and 23.3 months for LC patients (p = 0.5995). Median overall survival (OS) was 22.3 months for EC and 39.2 months for LC patients (p = 0.0232). The incidence of serious adverse events (SAEs) was low. SAEs occurred in 3/44 EC (6.8 %), 4/105 LC (3.8 %), and 1/10 MEC patients (10.0 %). One SAE in EC and one in LC resulted in death.

CONCLUSIONS

 In contrast to the new definition of castration resistance, AA + P was still more frequently used in daily clinical practice during the study observation period in patients treated with antiandrogens of the first generation after occurrence of castration resistance. Nevertheless, AA + P therapy appears to be effective and well tolerated during clinical routine in mCRPC patients. A comparison of the study results with earlier 'real-world' studies, however, has to take limiting factors into account. The observed difference in median overall survival might be explained by the imbalance of baseline characteristics between both cohorts with regard to number of patients, patients already deceased at start of documentation, patients with visceral metastases and patients with opioids at start of AA + P. For these reasons, patients in the EC initially might have had a poorer prognosis. A prospective randomised and controlled clinical trial would therefore be necessary to assess a possible difference in overall survival and response of the AA + P treatment with respect to therapy onset.

Using Data from a Sickness Fund Claims Database to Assess the Treatment Patterns and Healthcare Resource Utilization among Patients with Metastatic Renal Cell Carcinoma in Germany

OBJECTIVES

To characterize real-world prescribing patterns and their clinical and healthcare resource utilization (HRU) implications in patients with metastatic renal cell carcinoma (mRCC) treated in Germany.

METHODS

Eligible individuals were enrolled in the "Bundesverband der Betriebskrankenkassen" claims database and received targeted mRCC therapy between 1 January 2008 and 31 December 2016. Prescribing patterns and HRU were characterized by treatment line and summarized by descriptive statistics. Proxy progression-free survival (PFS) and overall survival (OS) were estimated using Kaplan-Meier curves.

RESULTS

536 patients receiving mRCC treatment were included. The median treatment duration was 4.2 months (interquartile range [IQR]: 1.7-9.3) for first-line therapy and 3.8 months (IQR: 1.7-9.1) for second-line therapy. Median PFS and OS estimates were similar for the first- and second-line treatments: PFS, 7.4 versus 7.2 months; OS, 14.9 versus 13.6 months. Mean HRU costs were higher for patients receiving first-line therapy (€7,253.2) compared with those receiving second-line therapy (€6,242.9). Exploratory stratification of outcomes by centre expertise suggested a possible trend towards improved OS in the 10 most experienced centres versus all -others: first-line, 18.4 versus 13.2 months; second-line, 16.4 versus 12.4 months.

CONCLUSIONS

In routine care, German clinicians make rational prescribing decisions; possible variations in outcomes between centres warrant further investigation.

Molecular analysis of circulating tumor cells of metastatic castration-resistant Prostate Cancer Patients receiving 177Lu-PSMA-617 Radioligand Therapy

Rationale: Lu-177-PSMA-617 radioligand therapy (RLT) is currently under approval for treatment of metastatic castration resistant prostate cancer (mCRPC) patients with late stage disease. However, previous studies demonstrated both heterogeneity of prostate specific membrane antigen (PSMA) expression, as well as response to PSMA treatment among mCRPC patients. Thus, there is an unmet need for identifying predictive parametres prior or under PSMA-RLT treatment. We therefore aimed to correlate several clinical and molecular parameters with response to PSMA treatment in a cohort of mCRPC patients undergoing PSMA RLT followed by a detailed analysis of promising candidates.

Methods: Nineteen patients, median age 68.8 years (range: 56.9 - 83.3) with mCRPC were included in this study. We performed baseline analysis of clinical parameters based on PSMA PET/CT, (metabolic tumor volume (MTV), total tumor volume (TTV)), serum PSA, ALP, LDH and gene expression analysis of circulating tumor cells (expression of AR full length (AR-FL), AR splice variant 7 (AR-V7), PSA and PSMA) as well as common markers for neuroendocrine differentiation (NED).

Results: Patients presented with bone, lymph node, and visceral metastases (89%, 68%, and 21%, respectively). All patients were pretreated with docetaxel, either abiraterone or enzalutamide, or both. Biochemical response in terms of PSA decline ≥50 or ≥30% was observed in 42% and 63%, respectively. There were significant correlations between PSA and PSMA mRNA expression, as well as tumor volumes (both MTV and TTV), AR-FL and AR-V7 mRNA expression. However, there was no correlation with response to PSMA treatment. Furthermore, none of these parameters was significantly correlated with baseline serum PSA values. Common NED markers were shown to be specifically high expressed and revealed impact on OS independent from AR-V7 gene expression.

Conclusion: We demonstrate that AR-FL and its splice variant AR-V7 might serve as prognostic biomarkers displaying high tumor burden in mCRPC patient prior to PSMA-RLT. Contrary, PSMA, which has been discussed as a biomarker for PSMA targeted treatment, does not display strong prognostic ability - at least on the mRNA level. Surprisingly, none of these parameters correlates to response to PSMA treatment. In contrast, commom NED markers such as SYP and ENO2 as well as FOXA1 expression level seem to predict OS, but not PFS, more reliably. We admit that a limitation of our study is the focus on mRNA expression of potential biomarkers only. Further investigations analyzing the potential role of protein expression of these markers are therefore warranted.

Prior therapies as prognostic factors of overall survival in metastatic castration-resistant prostate cancer patients treated with [177Lu]Lu-PSMA-617. A WARMTH multicenter study (the 617 trial)

Introduction

The impact of prior therapies, especially chemotherapy, on overall survival (OS) in patients with castration-resistant prostate cancer (CRPC) receiving [¹⁷⁷Lu]Lu-PSMA-617 therapy has been the subject of controversy. Therefore, WARMTH decided to plan a multicenter retrospective analysis (the “617 trial”) to evaluate response rate and OS as well as the impact of prior therapies on OS in more than 300 patients treated with ¹⁷⁷Lu-PSMA-617.

Materials and methods

The data of 631 metastatic CRPC (mCRPC) patients from 11 different clinics were evaluated. According to the inclusion and exclusion criteria, all patients had to have received at least abiraterone or enzalutamide prior to [¹⁷⁷Lu]Lu-PSMA-617 therapy. The patients were divided into three groups: patients who had received prior chemotherapy, patients who avoided chemotherapy, and patients for whom a chemotherapy was contraindicated.

Results

The analysis included the data of 416 patients, with a median age of 71.9 years. At the time of analysis, 87 patients (20,9%) were still alive. A total of 53.6% of patients had received both abiraterone and enzalutamide; 75.5% and 26.4% had a history of chemotherapy with docetaxel and cabazitaxel, respectively. A total of 20.4% had had Ra-223. The median OS was 11.1 months. Prior chemotherapy, the existence of bone and liver metastases, as well as Eastern Cooperative Oncology Group (ECOG) status, were significant prognosticators of worse overall survival in both univariate and multivariate analyses. Patients without any prior chemotherapy showed a significantly longer OS (14.6 months). The median OS in patients who received one or two lines of chemotherapy with docetaxel or docetaxel followed by cabazitaxel, respectively, was 10.9 months and 8.9 months. There was no difference in OS between patients who had not received chemotherapy and patients for whom chemotherapy was contraindicated. The other prior therapies did not have any significant impact on OS.

Conclusion

In the present multicenter analysis, chemotherapy-naïve mCRPC patients receiving [¹⁷⁷Lu]Lu-PSMA-617 therapy had a significantly longer OS than patients with a history of chemotherapy. This remained independent in the multivariate analysis besides presence of bone and liver metastases as negative prognosticators for survival, whereas an ECOG of 0–1 is associated with a longer OS.

Electronic supplementary material

The online version of this article (10.1007/s00259-020-04797-9) contains supplementary material, which is available to authorized users.

[Changes in the treatment of metastatic prostate cancer-new data and open questions]

The availability of taxane-based chemotherapy and androgen-receptor-targeted agents (ARTAs) have significantly broadened the therapeutic options for patients with metastatic prostate cancer and may also result in longer patient survival. The therapeutic sequence of ARTAs and taxanes may influence outcome and therefore decisions should be made on an individual basis. This article provides guidance for therapeutic decision-making in daily clinical practice by working out criteria that can be used to support individual therapeutic decisions. The focus is on metastatic castration-naive prostate cancer, oligometastatic disease as well as non-metastatic and metastatic castration-resistant prostate cancer.

[Treatment situation in metastastic Castration Naive Prostate Cancer (mCRPC) and the implications on clinical routine]

There is an ongoing change of paradigm in the treatment of metastatic prostate cancer (mPC). Taxan-based chemotherapy demonstrated a prolonged survival of patients in several randomized phase III trials. This is true in the situation of metastatic castration-resistent prostate cancer (mCRPC) as well as in the hormone-naïve stage (metastatic castration-naive PC [mCNPC]). In patients with mCNPC, treatment with docetaxel in combination with androgen deprivation therapy (ADT) prolonged the median total survival time by 15 months in comparison to ADT alone. Comparable results were obtained by the endocrine combination treatment with ADT/abiraterone. With the current data in mind it seems to be useful to discuss the value of early combination therapy with ADT/docetaxel or ADT/abiraterone as well as the impact on further treatment options in the mCRPC setting and to define criteria for treatment decisions in clinical practice.

SPARTAN: Gezielte Analyse der Resistenzen

Beim metastasierten kastrationsresistenten Prostatakarzinom (mCRPC) erfolgt heute eine Sequenztherapie. Daher müssen sich neue Wirkstoffe, die früher - im nicht-metastasierten kastrationsresistenten Stadium (M0CRPC) mit hohem Metastasierungsrisiko - eingesetzt werden, ebenfalls in diese Sequenz einfügen.

SWITCH II: Phase III randomized, sequential, open-label study to evaluate the efficacy and safety of sorafenib-pazopanib versus pazopanib-sorafenib in the treatment of advanced or metastatic renal cell carcinoma (AUO AN 33/11)

PURPOSE

This trial compared the sequential therapy with the multikinase inhibitor sorafenib (So) followed by pazopanib (Pa) or vice versa in advanced/metastatic renal cell carcinoma (mRCC) patients.

METHODS

This multicenter, randomized phase 3 study assessed the sequential use of So-Pa versus Pa-So in patients with mRCC without prior systemic therapy. Pts were randomized to So 2 × 400 mg/day followed by Pa 1 × 800 mg/day in case of progression or intolerable toxicity or vice versa. Primary endpoint was total PFS (tPFS), defined as time from randomization to progression, or death during second-line therapy. Key secondary endpoints included overall survival (OS), first-line PFS, disease control rate (DCR) and safety.

RESULTS

A total of 377 pts were randomized (So-Pa, n = 189; Pa-So, n = 188). Recruitment of a total 544 pts was calculated, but actual accrual rate turned out to be lower than expected. The primary endpoint median tPFS was 8.6 mo (95% CI 7.7-10.2) for So-Pa and 12.9 mo (95% CI 10.8-15.2) for Pa-So with a hazard ratio (HR) of 1.36 (upper limit of one-sided 95% CI 1.68), which exceeded a predefined HR <1.225 as a one-sided 95% confidence interval. Non-inferiority of So-Pa regarding tPFS was not met. Secondary endpoints displayed marked statistical differences in favor of Pa-So in first-line PFS and DCR but not for OS and 2nd-line PFS. Side effect profiles were consistent with known toxicities of the respective multikinase-inhibitor including diarrhea, fatigue, hand-foot skin reaction and hypertension.

CONCLUSIONS

Non-inferiority of the primary endpoint tPFS could not be demonstrated for So-Pa. The results for first-line PFS and DCR favored the Pa-So sequence.

TRIAL REGISTRATION

NCT01613846, www.clinicaltrials.gov.

[Use of the S3 guidelines for early detection of prostate cancer in urological practices]

OBJECTIVES

The German S3 guideline on prostate cancer gives recommendations on early detection of prostate cancer. In this study we analyzed the adherence of urologists in private practice from the administrative district of Münster, Germany to this guideline.

METHODS

Data were collected through a semistructured survey of 22 urologists based on the COREQ checklist (Consolidated criteria for reporting qualitative research) in four focus groups consisting of five or six urologists in private practice. We developed 23 questions relating to 12 recommendations of the paragraphs of the S3 guidelines dealing with early detection of prostate cancer and prostate biopsy. The recommendations of the guideline are subdivided in nine "strong", one "optional recommendation" and two "statements". The adherence to the guideline was investigated by using frequency and qualitative content analysis (Mayring) based on a mixed methods design.

RESULTS

The urologists follow six of the nine "strong recommendations" of the guideline and deviate from three. Reasons for deviations from "strong recommendations" are the following: information about advantages and disadvantages of early detection for prostate cancer, recommendation of a prostate biopsy in case of PSA level ≥4 ng/ml, and indication for repeat biopsy.

CONCLUSION

Most of the "strong recommendations" are followed by the interviewed urologists of the administrative district of Münster. Contextually relevant deviations from "strong recommendations" are justified, e. g., the only limited transferability of the PSA threshold of 4 ng/ml derived from population-based studies of asymptomatic men to men presenting in a urologist's office.

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.

Diagnostic performance of 18F-PSMA-1007 PET/CT in patients with biochemical recurrent prostate cancer

PURPOSE

The introduction of ligands targeting prostate-specific membrane antigen (PSMA), especially ⁶⁸Ga-PSMA-11, has changed the management of patients with prostate cancer (PCa). ¹⁸F-Labelled ligands can be produced in larger amounts and therefore can improve availability for a larger group of patients. The aim of this study was to evaluate the diagnostic performance of the recently introduced ¹⁸F-PSMA-1007 in patients with recurrent PCa.

METHODS

This retrospective analysis included 100 consecutive patients with biochemical relapse (mean age 68.75 ± 7.6 years) referred for PSMA PET/CT. Whole-body PET/CT imaging (from the lower limbs to the skull) was performed in all patients 120 min after injection of 338 ± 44.31 MBq ¹⁸F-PSMA-1007. Prostatectomy, radiation beam therapy of the prostate bed and androgen-deprivation therapy had been performed in 92%, 45% and 27% of the patients, respectively. Radiation beam therapy of the prostate bed had been performed in addition to surgery in 38 patients (38%) and 10 patients (10%) had received all three therapy modalities. The probability of a ¹⁸F-PSMA-1007 PET/CT scan suggestive of pathology was compared with the Gleason score (GS) and PSA level.

RESULTS

Of the 100 patients, 95 (95%) showed at least one pathological finding on ¹⁸F-PSMA-1007 PET/CT. The overall median PSA level was 1.34 ng/ml (range 0,04-41.3 ng/ml). The rates of pathological scans were 86%, 89%, 100% and 100% among patients with PSA levels ≤0.5, 0.51-1.0, 1.1-2.0 and > 2.0 ng/ml, respectively. The median GS was 7 (range 5-10). The majority of patients (70) with a GS available had a score in the range 7-9. The rate of pathological scans in these patients was 93% (65/70). The median SUV_max values of the pathological findings were 10.25, 14.32, 13.16 and 28.87 in patients with PSA levels ≤0.5, 0.51-1.0, 1.1-2.0 and >2.0 ng/ml, respectively. The median SUV_max in patients with a PSA level of >2.0 ng/ml was significantly higher than in all other PSA groups.

CONCLUSION

¹⁸F-PSMA-1007 PET/CT can detect recurrent PCa in a high percentage of patients with biochemical relapse. The probability of a pathological ¹⁸F-PSMA-1007 PET/CT scan seems to be high even in patients with a low PSA level ≤0.5 ng/ml, and this may have a significant impact on the management of this relevant group of patients.

18F-PSMA-1007 PET/CT at 60 and 120 minutes in patients with prostate cancer: biodistribution, tumour detection and activity kinetics

PURPOSE

PSMA-targeted PET in patients with prostate cancer (PCa) has a significant impact on treatment decisions. By far the most frequently used PSMA ligand is ⁶⁸Ga-labelled PSMA-11. However, due to the availability of larger amounts of activity, ¹⁸F-labelled PSMA ligands are of major interest. The aim of the present study was to evaluate the biodistribution and performance of the novel ¹⁸F-labelled ligand PSMA-1007 at two different time points.

METHODS

This retrospective analysis included 40 consecutive patients (mean age 68.7 ± 8.1 years) referred for PSMA PET/CT. ¹⁸F-PSMA-1007 PET/CT was performed for localization of biochemical relapse, primary staging or therapy follow-up. Circular regions of interest were placed on representative slices of the liver, spleen, kidney, abdominal aortic blood pool, bone marrow (fourth lumbar vertebral body), urinary bladder and gluteus muscle at 60 and 120 min after injection. In malignant lesions the maximum standardized uptake (SUV_max) was measured within volumes of interest at both time points. All SUVs at 60 min were compared with those at 120 min after injection.

RESULTS

The activity in the blood pool, urinary bladder and gluteus muscle was very low and decreased significantly over time (P < 0.001). Uptake in the liver, spleen and kidney showed a significant increase over time and uptake in the bone marrow remained stable. Overall, 135 PCa lesions were detected at 60 min and 136 lesions at 120 min after injection. The median SUV_max increased significantly (P < 0.001) from 10.98 to 15.51 between 60 and 120 min.

CONCLUSION

PCa lesions show a significant increase in ¹⁸F-PSMA-1007 uptake at 120 min compared with 60 min after injection. In addition, accumulation of the tracer in the urinary bladder was very low leading to improved contrast of adjacent PCa lesions. Increasing accumulation in the liver may limit the sensitivity of the tracer in detecting liver metastases.

Expression of PSMA in tumor neovasculature of high grade sarcomas including synovial sarcoma, rhabdomyosarcoma, undifferentiated sarcoma and MPNST

AIMS

PSMA (prostate specific membrane antigen) is physiologically expressed in normal prostate tissue. It is overexpressed in prostate cancer cells and has been suggested as a target for antibody-based radioligand therapy. As PSMA expression so far has not been systematically analyzed in soft tissue tumors, the current study aims at investigating a large cohort of different subtypes.

METHODS AND RESULTS

Immunohistochemistry was used to detect PSMA expression in 779 samples of soft tissue tumors and Ewing sarcoma as a primary bone malignancy. CD34 coexpression was employed to study PSMA expression in the neovasculature. PSMA expression was found in the tumor-associated neovasculature of 151/779 soft tissue/bone tumors (19.38%) and was more frequent in malignant tumors compared to tumors with intermediate or benign biological potential (p=0.078). Strong neovascular PSMA expression was predominantly observed in subsets of different sarcomas including 3/20 rhabdomyosarcomas (15%), 4/21 malignant peripheral nerve sheath tumors (19.05%), 6/16 synovial sarcomas (35.29%) and 6/33 undifferentiated pleomorphic sarcomas (18.18%).

CONCLUSION

We conclude that PSMA is expressed in the neovasculature of a subset of soft tissue tumors to a variable extent. Our observation of strong PSMA expression predominantly occurring in sarcomas might provide a rationale to evaluate PSMA-targeted radioligand therapy in these entities.

Performance comparison of two androgen receptor splice variant 7 (AR-V7) detection methods

OBJECTIVES

To compare the performance of two established androgen receptor splice variant 7 (AR-V7) mRNA detection systems, as paradoxical responses to next-generation androgen-deprivation therapy in AR-V7 mRNA-positive circulating tumour cells (CTC) of patients with castration-resistant prostate cancer (CRPC) could be related to false-positive classification using detection systems with different sensitivities.

MATERIALS AND METHODS

We compared the performance of two established mRNA-based AR-V7 detection technologies using either SYBR Green or TaqMan chemistries. We assessed in vitro performance using eight genitourinary cancer cell lines and serial dilutions in three AR-V7-positive prostate cancer cell lines, as well as in 32 blood samples from patients with CRPC.

RESULTS

Both assays performed identically in the cell lines and serial dilutions showed identical diagnostic thresholds. Performance comparison in 32 clinical patient samples showed perfect concordance between the assays. In particular, both assays determined AR-V7 mRNA-positive CTCs in three patients with unexpected responses to next-generation anti-androgen therapy. Thus, technical differences between the assays can be excluded as the underlying reason for the unexpected responses to next-generation anti-androgen therapy in a subset of AR-V7 patients.

CONCLUSIONS

Irrespective of the method used, patients with AR-V7 mRNA-positive CRPC should not be systematically precluded from an otherwise safe treatment option.