BACKGROUND:For over a decade the Advanced Prostate Cancer Consensus Conference (APCCC) covers a variety of topics that greatly impact daily practice. In 2025, a dedicated event was organised to discuss key questions in clinical management of patients with prostate cancer (PC) related to diagnostic tools (APCCC Diagnostics). Here we present the voting results of the APCCC Diagnostics questions. OBJECTIVE; DESIGN, SETTING, AND PARTECIPANTS: APCCC Diagnostics 2025 is a pilot project. The scientific committee for APCCC Diagnostics 2025 developed 88 multiple-choice consensus questions on six different topics. Prior to the conference, the panel members (''panellists'') voted on these questions via a web-based survey. Consensus was defined as ≥75% agreement, with strong consensus defined as ≥90% agreement. OUTCOMES MEASUREMENTS AND STATISTICAL ANALYSIS:Consensus was only reached on 17 of 88 questions (19%), of which six (7%) received a strong consensus. Specifically, consensus was reached for two of 17 questions (14%) in "how to diagnose PC"; seven of 16 (44%) in "how to stage PC"; three of 14 (21%) in "Biochemical Recurrence Scenario"; two of 11 (18%) in "metastatic disease: what to do?"; zero of 18 (0%) in "monitoring metastatic PC"; and three of 12 (25%) in "radioligand therapy and imaging." CONCLUSIONS:The voting results and their discussion may assist physicians in navigating controversial areas of clinical management related to diagnosis, staging, and restaging in the different clinical settings for PC, particularly where high-level evidence is scarce or conflicting. The findings can also help funders and policymakers in prioritising areas for future research.

Abstract The evolution to metastatic disease is a major determinant of cancer mortality. Cancer evolution involves a complex interplay between intrinsic genetics and transcriptional alterations and the microenvironment. To define mechanisms underpinning metastatic heterogeneity in late-stage disease, we focus on metastatic castration-resistant prostate cancer and employed single-cell multi-omics and whole-genome sequencing to deeply profile 34 metastatic lesions obtained from 9 patients through rapid autopsy. We find evolutionary convergence of intra-tumour heterogeneity, characterised by recurrent tumour populations acting as critical functional components of the tumour ecosystem, irrespective of clonal and microenvironmental backgrounds. We find little evidence of the microenvironment driving transcriptional heterogeneity, but there are signatures of co-adaptation between the microenvironment and tumour cells. In contrast, clonal evolution primarily foster widespread transcriptional changes that did not result in de novo functional states. Intra-patient functional convergence of tumour ecosystems across metastases indicates system-level selection pressures that drive the heterogeneity landscape of metastatic castration-resistant prostate cancer. Our findings reveal functional evolutionary convergence of metastatic disease into distinct intra-tumour subpopulations, identifying critical determinants for therapeutic targeting.

5001 Background: DGC predicts overall survival (OS) benefit from DOC when added to ADT while the benefit of adding DOC to ADT and ENZ is unknown. We hypothesized in a locked prespecified statistical analysis plan that higher GC score (> 0.85, the locked threshold on clinical test report) will identify patients who benefit from addition of DOC to ADT plus ENZ independently of metastases volume and timing. Methods: DGC scores were generated from transcriptome profiling using a clinical test (Veracyte) on tumor index cores from participants (pts) randomised on ENZAMET study (N = 1,125) 1:1 ADT with NSAA or ENZ with clinical discretion to add DOC as part of standard of care. Primary tumor samples were available from 764 pts. Differential DOC OS benefit was assessed by testing the marker-by-treatment interaction term in propensity score-weighted Cox models, with weights based on factors associated with planned DOC use. Prognostic effects of DGC were estimated using Cox for age, WHO PS, Gleason, randomized arm +/- planned DOC, metastases volume and timing, with adjusted hazard ratios (aHR) and 95% CIs. Analyses were prespecified and conducted independently by two statisticians. Results: DGC scores were available for 634 (83%) unique pts (median follow-up 5.6 years) with clinical factors representative of the overall trial. Median age was 68 yrs with 50% HV, 62% synchronous presentation, and 44% with planned DOC. Planned DOC was associated with younger age, high volume and synchronous presentation (all p≤0.002). Median DGC score was 0.88 (IQR 0.75-0.96) and 55% had DGC > 0.85 (62% in pts with DOC planned, 49% in others). Overall, higher GC was significantly associated with poorer OS (aHR 1.37 [1.06-1.78], p = 0.02). DOC benefit differed by GC level [higher vs lower] in pts treated with ADT plus ENZ (p-interaction 0.043). Higher DGC was associated with worse OS in pts treated with ADT plus ENZ (aHR 2.31 [95% CI 1.26-4.21], p = 0.007) while pts treated with DOC added to ADT plus ENZ showed no significant difference by DGC (aHR 1.08 [0.63–1.86]). Effects were more pronounced in pts with high vs. low volume disease. Conclusions: DGC > 0.85 is predictive of benefit from adding DOC to ADT plus ENZ as it negated the poor prognostic outcome of DGC > 0.85 with ADT plus ENZ alone, whereas there was no evidence of benefit for adding DOC for pts with GC ≤0.85. 5yr OS N Lower Decipher Higher Decipher Higher vs. loweradj. HR (95% CI) Overall 634 71%(66-77%) 57%(51-62%) 1.37(1.1, 1.8) ADT+ENZ 178 86%(78-93%) 62%(52-72%) 2.29(1.3, 4.2) ADT+ENZ+DOC 142 66%(53-79%) 58%(48-68%) 1.08(0.6, 1.9) ADT+ENZ (LV) 123 88%(80-96%) 72%(61-84%) 1.96(0.9, 4.3) ADT+ENZ+DOC (LV) 44 86%(67-100%) 79%(64-94%) 1.70(0.3, 9.0) ADT+ENZ (HV) 55 81%(65-96%) 41%(23-60%) 2.83(1.1, 7.5) ADT+ENZ+DOC (HV) 98 58%(42-75%) 48%(36-61%) 1.07(0.6, 1.9)

Importance:The ideal duration of androgen deprivation therapy (ADT) for treating localized prostate cancer is unknown due to variable adherence and treatment durations tested in clinical trials. Objective:To determine the ideal duration of ADT for patients with prostate cancer treated with radiotherapy. Data Sources:This individual patient data meta-analysis of 13 randomized phase 3 clinical trials evaluated the use of radiotherapy alone or with ADT. It included patients with a median follow-up of 11.3 (IQR, 9.5-14.5) years and ADT duration of 0 to 36 months. Most patients (7392 [72%]) included had National Comprehensive Cancer Network high-risk or very high-risk disease. Study Selection:For this meta-analysis, a systematic literature search from 1980 to 2020 was performed in trial registries (Cochrane Central Register of Controlled Trials and ClinicalTrials.gov), MEDLINE (1966-2020), Embase (1982-2020), Web of Science, and Scopus to identify trials. Data Extraction and Synthesis:Intention-to-treat and as-treated analyses were performed. The number needed to treat to prevent 1 distant metastasis at 10 years was calculated based on prognostic risk group. The analyses were conducted from January 5 to August 15, 2023. Main Outcomes and Measures:The primary end point for this study was overall survival, defined as time to death or last follow-up from randomization. Secondary end points included biochemical recurrence, distant metastasis (DM), prostate cancer-specific mortality, and other-cause mortality. Results:The median (IQR) age among the 10 266 male patients was 70 (65-74) years. Longer durations of ADT were associated with nonlinear improvement in relative benefits of DM, prostate cancer-specific mortality, and overall survival, with reduced estimated benefits beyond 9 to 12 months of ADT based on the end point. There was a near-linear increase in other-cause mortality associated with long-term ADT use (hazard ratio, 1.28; 95% CI, 1.09-1.50; P = .002 for 28 vs 0 months of ADT). The optimal ADT duration based on 10-year DM was 0, 6, 12 months, and undefined for patients with 1 intermediate-risk factor, 2 or more intermediate-risk factors, and National Comprehensive Cancer Network high-risk and very high-risk disease, respectively. Conclusions and Relevance:The results of this meta-analysis suggest that, for men with localized prostate cancer treated with definitive radiotherapy and ADT, there are relative and absolute benefits from increasing durations of ADT that help provide individualized risk estimates.

173 Background: Sarcopenia is common in advanced prostate cancer and worsened by androgen deprivation therapy (ADT). Routine staging CT scans provide an opportunity to screen for sarcopenia. The STAMPEDE trials have demonstrated treatment intensification beyond ADT improve cancer outcomes; however, benefits are heterogeneous. This study investigates CT-derived skeletal muscle index (SMI), a validated marker of total muscle mass, as a prognostic and predictive biomarker in the STAMPEDE docetaxel and ARPI trials. Methods: Men with newly diagnosed non-metastatic high-risk (M0) and metastatic (M1) hormone-sensitive prostate cancer (HSPC) with available staging CT imaging in the STAMPEDE docetaxel or ARPI trials were included. These trials compared standard of care (SOC) with addition of docetaxel ± zoledronic acid (ZA) or abiraterone acetate with prednisolone (AAP) ± enzalutamide (Enz). SMI (cm²/m²) was calculated as mean muscle area divided by height squared. Outcomes were overall survival (OS) in M1 patients and metastasis-free survival (MFS) in M0. Prognostic utility of SMI was evaluated in Kaplan–Meier analyses and Cox regression models. Predictive value was assessed by comparing hazard ratios of the treatment effect in Cox models for high vs low SMI cohorts. Likelihood ratio tests were used to identify treatment-SMI interactions. Continuous predictive effects were examined using multivariable fractional polynomial interaction (MFPI) models. Results: 2,267 patients (1,578 M1, 689 M0) met inclusion criteria. The median SMI was 47.2cm²/m² (IQR 42-52) in M1 patients and 48.2cm²/m² (IQR 44-54) in M0. SMI and CHAARTED burden were identified as independent prognostic biomarkers in M1 patients, with a 10 cm²/m² increase in SMI associated with a 15% reduction in risk of death (HR 0.85, 95% CI 0.79–0.92, p<0.001). SMI was not an independent prognostic biomarker in M0 patients. SMI was identified as an independent predictive biomarker of MFS benefit upon addition of AAP±Enz in M0 patients; high SMI cohorts had greater MFS benefit from addition of AAP±Enz compared with the low SMI cohort (HR 0.44 [0.3-0.66] vs 0.59 [0.38-0.91]). Likelihood ratio tests confirmed that adding a treatment-SMI interaction improved prediction of treatment benefit (χ²: 4.67, p=0.03). MFPI modelling demonstrated a significant MFS benefit with addition of AAP±Enz in M0 patients (χ²=9.95, p=0.006) with increasing SMI, however this benefit was observed in the range of 41-63 cm 2 /m 2 only. 20% of our cohort lay outside this range (13% lower, 7% higher) and did not observe MFS benefit from addition of AAP±Enz to SOC. Conclusions: SMI is an independent prognostic biomarker in trial patients with de novo metastatic HSPC. SMI is predictive of improved MFS with addition of AAP±Enz to SOC in M0 disease. Further research is required to validate our findings in real-world cohorts.

TPS412 Background: PARP inhibitors (PARPi) are approved for the treatment of patients with metastatic castration-resistant prostate cancer. Saruparib is a new generation PARPi that selectively inhibits and traps PARP1. In the Phase I/IIa PETRA study (NCT04644068), activity with saruparib monotherapy (PSA 50 , objective response) has been observed in patients with advanced/metastatic prostate cancer. The Phase I/II PETRANHA study (NCT05367440) has demonstrated that saruparib can be safely combined with androgen receptor pathway inhibitors to treat patients with metastatic prostate cancer. The Phase III EvoPAR-Prostate02 study (NCT06952803) is evaluating the efficacy and safety of adjuvant saruparib versus placebo in patients with early-stage, high-risk prostate cancer with BRCA1 / BRCA2 gene mutation (BRCAm) who have received definitive radiotherapy (RT) and are receiving a standard concomitant androgen deprivation therapy (ADT) regimen. Methods: EvoPAR-Prostate02 is a two-cohort, randomized, double-blind, placebo-controlled study. Eligibility criteria include age ≥18 years, diagnosis of high-risk or very high-risk localized/locally advanced prostate adenocarcinoma or high-risk biochemical recurrence following radical prostatectomy, with a confirmed BRCAm by central tumor tissue testing. Patients must have completed primary or salvage RT with curative intent, with no evidence of disease or disease detected only in the pelvis at time of study entry, and must still be receiving ADT. Key exclusion criteria include persistent cytopenias, conditions with predisposition to bleeding, and history of myelodysplastic syndrome/acute myeloid leukemia. In both Cohort A (ADT alone) and Cohort B (ADT plus abiraterone/prednisone), randomization is 1:1 to saruparib or placebo. Treatment with saruparib/placebo continues for 24 months or until unacceptable toxicity, confirmed disease progression by blinded independent central review (BICR), or patient-initiated withdrawal. ADT and abiraterone treatment duration is limited to 24 months, inclusive of pre-study regimen. The primary endpoint is metastasis-free survival (MFS), confirmed by standard clinical imaging (computed tomography/magnetic resonance imaging and bone scan, or prostate-specific membrane antigen-positron emission tomography [PSMA PET]), as assessed by BICR. Overall survival (OS) is a key secondary endpoint. Statistical analyses of MFS and OS will be conducted within each cohort using a stratified log-rank test. Approximately 700 patients will be randomized. Recruitment began in July 2025 and is ongoing. Clinical trial information: NCT06952803 .

Prostate cancers with high proliferation rates have shorter survival times but when spread has occurred (metastatic), there is increased sensitivity to hormone therapy with abiraterone.

The prognosis of newly diagnosed metastatic prostate cancer is highly variable. The primary objective of the PARADIGM prospective cohort study was to evaluate predictors of survival in blood collected at the start of each of the first six treatment cycles from 114 patients with high-volume metastatic prostate cancer (biologically male) who were starting androgen deprivation therapy in combination with docetaxel or an androgen receptor pathway inhibitor. Here circulating tumor DNA (ctDNA) was detected in 29% of patients after 6-12 weeks of combination therapy (compared to 70% before any treatment) and associated with 12 month overall survival of 73% versus 99% for patients who were ctDNA-negative and 24 month survival of 50% versus 85%. The secondary objective was to test ctDNA with serum prostate-specific antigen (PSA). In multivariable models, both were independent risk factors on combination treatment with a hazard ratio of death of 20.34 for the poorest prognosis group, but only ctDNA was associated with shorter survival on androgen deprivation before the start of combination therapy. Using ctDNA with serum PSA and clinical characteristics can improve the accuracy of survival prediction and should be evaluated for ctDNA-informed treatment modification. ClinicalTrials.gov: NCT04067713 .

5099 Background: The international, randomized, phase III ENZAMET trial (n=1125) showed improved overall survival (OS) with ADT plus ENZA vs ADT plus NSAA for mHSPC. Observational studies showed that the mHSPC genetic landscape is comparable to castration resistant prostate cancer (CRPC). Prognostic and predictive impact of inherited pathogenic variants (PVs), including those affecting BRCA1 , BRCA2 and other DNA damage and repair (DDR) genes, on androgen receptor pathway inhibitor (ARPI)-treated mHSPC is under investigation. Methods: Whole exome sequencing of germline DNA prospectively obtained from ENZAMET pts. Variant annotation and effect prediction identified PVs (altered “+” vs wild-type “-”). Prognostic effect of PVs was assessed within arms. Endpoints: clinical progression-free survival (PFS) and OS by Kaplan-Meier method. Hazard ratios (HRs) were estimated using Cox models. Multivariable analyses (MVA) adjusted for Gleason score (GS), volume (vol), metachronous vs synchronous and docetaxel (D) use. Results: All 847 available samples were successfully sequenced. 123 PVs were identified in 117 (13.8%) pts, of which 46 (5.43%) pts harbored a PV in ≥1 DDR gene. The rate of pathogenic germline BRCA1 / BRCA2 (BRCA) PVs was 2.13% (39.1% of DDR PVs). Proportions of arm, D use, vol and visceral disease were similar between DDR+ vs DDR- and BRCA+ vs BRCA-. Synchronous mHSPC in DDR+ vs DDR- and BRCA+ vs BRCA- was 41.3% vs 63.0% and 44.4% vs 62.2%, respectively. PFS and OS estimates were similar between BRCA+ and BRCA- groups in the overall cohort (5-yr OS: 55.6% vs 61%; 3-yr PFS: 50% vs 53.5%, respectively) and in the ENZA arm, but differed in the NSAA arm (Table). BRCA+ treated with ADT+NSAA (67% D use) had shortest PFS (median PFS: 11.3m vs 24.9m [BRCA-], HR 1.85, 95% CI: 0.95-3.6). D use associated with poorer outcomes. In MVA, the HR(PFS) for BRCA+ in NSAA arm was 1.47 (95% CI 0.71-3.04, p=0.3) vs ENZA arm: HR 0.98, (95% CI 0.31-3.08, p=0.97). Vol and GS were independently significant in both arms. Conclusions: In one of the largest germline genetic studies from a phase III mHSPC trial, we observed recurrent DDR and BRCA PVs at a lower rate than institutional cohorts. Germline BRCA PVs are associated with a shorter PFS on ADT+NSAA – an effect which may be mitigated by ENZA. Validation in independent trial cohorts is ongoing. Outcomes by arm/docetaxel and BRCA status. n 5y-OS % (95% CI) 3y-PFS % (95% CI) NSAA only BRCA- 238 56.6 (50.0-62.7) 42.9 (36.5-49.1) NSAA only BRCA+ 3 66.7 (5.4-94.5) 66.7 (5.4-94.5) NSAA+D BRCA- 176 54.7 (47.0-61.8) 32.5 (25.7-39.6) NSAA+D BRCA+ 6 33.3 (4.6-67.6) 16.7 (0.8-51.7) ENZA only BRCA- 228 70.6 (64.2-76.0) 73.3 (67.0-78.5) ENZA only BRCA+ 7 71.4 (25.8-92.0) 71.4 (25.8-92.0) ENZA+D BRCA- 187 60.7 (53.2-67.3) 62.3 (54.9-58.8) ENZA+D BRCA+ 2 NE 50.0 (0.6-91.0)

PURPOSE:The continuous development of new imaging approaches, molecular phenotyping, genetic subtypes, prognosis assessments, and effective therapies across a range of disease states has created a need to redefine terminology and best practices for clinical trial conduct in patients with advanced prostate cancer. METHODS:We convened an international expert committee of diverse working groups, the Prostate Cancer Working Group 4 (PCWG4), between 2016 and 2025. Our objective was to formulate updated criteria based on emerging evidence and clinical trial data in a biomarker context to provide guidance for clinical trial design, eligibility, and end point assessments for patients with advanced prostate cancer. RESULTS:PCWG4 redefines terminology around the disease state and previous therapies in a patient-centric context and terminology focused on androgen pathway modulation. We consider imaging, with a particular focus on positron emission tomography (PET)-defined disease. New recommendations are provided for disease state terminology, defining eligibility criteria, response and delay/prevent end points, intervals for reassessments including imaging, and patient-reported outcome determination. We provide recommendations in a biomarker-based context of use for the intended indication, reflective of patient benefit for specific interventions. We emphasize the need for development of validated PET imaging and molecular and phenotypic criteria as well as trial designs to appropriately risk stratify patients, predict and assess benefit, and measure post-treatment outcomes reliably in a trial framework. CONCLUSION:PCWG4 updates recommendations on patient and tumor characterization, therapy development, and imaging criteria and extends guidance into earlier androgen pathway modulator-naïve/sensitive disease states to reflect an evolving, heterogeneous, and diverse patient population to optimize treatment benefits for all patients.

Prostate cancer is a heterogeneous disease comprising diverse cell types within the tumor microenvironment that support cancer cell survival. Using single cell and spatial transcriptomics, we previously identified subpopulations of treatment-persistent cancer cells exhibiting regenerative properties and a distinct molecular signature. Herein, we aimed to characterize the locked ‘Persist’ signature (PS) and its association with outcomes in a large cohort of non-metastatic prostate cancer tumors. Patients with non-metastatic prostate cancer that underwent Decipher prostate genomic classifier and whole-transcriptome profiling on biopsy (BX, n=146,941) and radical prostatectomy (RP, n=55,329) specimens between October 2016 and February 2024 were included (Veracyte Inc., San Diego, CA, USA). Baseline clinical and pathological data from deidentified patients as well as signature scores were retrieved from the Decipher Genomic Resource for Intelligent Discovery (GRID) registry (Clinical Trials identifier: NCT02609269). The PS score based on the expression of 17 genes was calculated for all samples. PS was significantly associated with adverse clinical and pathological variables. In biopsy sample, PS was higher in cases with worse T3/4 clinical stage, Grade group (GG4-5), and high/very high NCCN risk (p<0.001 for all). In RP sample, PS was significantly higher in patients with GG4-5, extraprostatic extension, seminal vesicle invasion and lymph node involvement (p<0.001 for all). PS was also higher in patients with very high Decipher (>0.85) in both BX and RP (p<0.001 for both). When evaluating the prognosis of PS in multiple retrospective cohorts, PS in biopsy was prognostic of adverse pathology features at RP. PS was also prognostic of distance metastasis (DM) in multiple RP cohorts with long-term follow up (META855). In the ARNEO trial testing apalutamide in addition to ADT as neo-adjuvant treatment prior RP, PS was prognostic of early recurrence. In the Stampede trial, PS was prognostic of progression free survival, PCSM and OS in both non-metastatic and metastatic disease. When associating PS with other GRID signatures, PS was higher in samples with homologous recombination deficiency, TP53 mutations, Luminal B and luminal proliferating subtypes. On the other hand, PS was lower in samples with low androgen receptor-activity, RB-loss and neuroendocrine-like tumors. Finally, PS was positively correlated with radiation sensitivity signatures. Persist is a novel molecular signature associated with more aggressive tumor characteristics. Future studies aim to further examine beyond this signature potential to identify patients at risk of aggressive prostate cancer, and understand what the optimal treatments for those with treatment-persistent prostate cancer cells are. Francesco Ballesio, Sinja Taavitsainen, Mohammed Alshalalfa, Antti Kiviaho, Mazlina Ismail, Reetta Nätkin, Alexander Giesen, Thomas Munro, James A. Proudfoot, Hyunnam Ryu, Elai Davicioni, Matthew C. Cooperberg, R. Jeffrey. Karnes, Ruochen Jiang, Steven Joniau, Gerhardt Attard, Frank Claessens, Matti Nykter, Alfonso Urbanucci. Persist: a molecular signature for prostate cancer patients with preexisting treatment-persistent cells associated with aggressive disease [abstract]. In: Proceedings of the AACR Special Conference in Cancer Research: Innovations in Prostate Cancer Research and Treatment; 2026 Jan 20-22; Philadelphia PA. Philadelphia (PA): AACR; Cancer Res 2026;86(2_Suppl):Abstract nr B079.

Circulating analytes in cancer patients capture tumor-related signals. We profiled matched extracellular vesicle (EV) total RNA and cell-free DNA (cfDNA) from the same plasma aliquots of chemo-naive metastatic castration-resistant prostate cancer (mCRPC) patients treated with Enzalutamide (n=54 patients, n=119 longitudinal samples; NCT06981377 ) at four Italian clinical centers and interrogated data from >10,000 cancer patients' and healthy individuals' samples. Transcript integrity analysis identified coding and non-coding species with fragmentation patterns varying across RNA biotypes. EV-RNA data deconvolution revealed signal from immune populations, including fractions classified as CD4+ T cells, whose abundance increased with disease progression in plasma EVs and mCRPC tissues. By leveraging tissue data-informed mining, we established a novel prostate cancer-related EV-RNA signature that resulted in an independent predictor of poor prognosis and captured tumor microenvironment-derived signals. Integrating EV-RNA and ctDNA information improved patient stratification for progression-free survival. These findings suggest a multifaceted role for plasma EVs as a source of cancer biomarkers.

ERG fusions occur in about 50% of prostate cancers (PCa) and represent early somatic events that co-initiate tumorigenesis. Yet, the molecular programs unleashed by ERG at disease onset remain elusive. Here, the inducible, temporally controlled expression of ERG enabled the accurate mapping of early ERG-driven processes associated with an apparent decrease in cell fitness across a panel of prostate cells. We observed that ERG triggers senescence and epithelial-mesenchymal transition (EMT), generating distinct cellular states in which EMT and senescence coexist in the same cell or occur independently. ERG-mediated activation of canonical and non-canonical TGF beta signaling differentially regulates EMT and senescence markers. Moreover, ERG drives context-dependent changes in cell identity and promotes an intermediate basal-luminal cell population with stem cell gene expression. Notably, p53 loss enhances ERG-driven expression of cell plasticity markers without affecting senescence. Transcriptomic investigation of ERG-expressing epithelial cells revealed activation of inflammatory signals. Conditioned medium experiments demonstrated paracrine-mediated inflammation in epithelial ERG-negative, stromal, and myeloid cells. Consistently, patient-derived expression data from 5 independent cohorts and 2,048 men showed activation of TNFA-NFKB and TGF beta signaling in ERG-rearranged tumors. Further, deconvolution analysis indicated a higher infiltration of inflammatory macrophages in ERG-positive tumors. Altogether, we uncovered a previously unrecognized triad of ERG-driven processes -dedifferentiation, senescence, and inflammation- that may underpin its oncogenic potential and shape PCa initiation and therapeutic response. Implications: Temporal control of ERG expression in prostate cells enabled accurate mapping of ERG-driven processes, identifying dedifferentiation, senescence, and inflammation as candidate contributors to ERG-dependent tumorigenesis and therapeutic response.

BACKGROUND:Serum prostate-specific antigen (PSA) concentrations decrease after hormone therapy for prostate cancer, with the nadir serving as a potentially useful prognostic biomarker. To support clinical use, we evaluated the association between PSA nadir values and survival outcomes, stratified by pre-treatment metastatic volume or, in patients with non-metastatic cancer, stratified by lymph node status. METHODS:As part of the STAMPEDE platform trial, patients with metastatic or very high-risk non-metastatic prostate adenocarcinoma were recruited to five randomised, controlled, phase 3 trials conducted at 126 hospitals or oncology centres in Switzerland and the UK. Patients were randomly assigned to either standard of care (androgren deprivation therapy [ADT] alone or ADT plus docetaxel) or to one of five experimental treatment groups: ADT plus docetaxel with or without zoledronic acid, ADT plus abiraterone acetate with or without enzalutamide, or ADT plus prostate radiotherapy (only patients with metastatic disease). We used trial data from these participants to perform landmark analyses to test associations of PSA at 6, 12, and 24 weeks after randomisation with overall survival. Only patients with a PSA value were included in each landmark analysis. The Kaplan-Meier method was used to estimate 96-month overall survival rates and the corresponding 95% CIs for patients categorised by either metastatic volume or lymph node status. The STAMPEDE protocol platform is registered with ClinicalTrials.gov (NCT00268476), EUDRACT (2004-000193-31), and ISRCTN (ISRCTN78818544). FINDINGS:This study included 7129 patients from the STAMPEDE platform, who were recruited between Oct 5, 2005, and Sept 2, 2016; 4438 had metastases and 2691 had very high-risk non-metastatic disease. Among patients with metastasis and volumetric assessment, 2211 (55·9%) of 3956 had high-volume metastases, and among those with non-metastatic disease, 1033 (38·4%) were lymph node positive. A PSA concentration of 0·2 ng/mL or less was less frequent at 6 weeks or 12 weeks, but was associated with equivalent survival rates, compared with a PSA of 0·2 ng/mL or less at 24 weeks. Survival rates of PSA subcategories (≤0·2 ng/mL, >0·2 to 1·0 ng/mL, >1·0 to 3·0 ng/mL, and >3·0 ng/mL) differed by metastatic volume or, in patients with non-metastatic disease, by nodal status. Survival was longest for patients allocated to abiraterone with or without enzalutamide. Among patients with metastatic disease in the abiraterone with or without enzalutamide group who had a PSA of 0·2 ng/mL or less at 24 weeks, 96-month overall survival in patients with low-volume metastatic disease (64·1% [95% CI 57·8-69·8]) was higher than in patients with high-volume metastatic disease (44·6% [37·1-51·9]), but lower than in patients with non-metastatic, node-positive disease (79·4% [73·8-83·9]). 96-month overall survival was highest for patients with non-metastatic, node-negative disease (82·8% [95% CI 78·7-86·1]). INTERPRETATION:Metastatic volume or nodal status influence survival rates associated with on-treatment serum PSA categories, including for undetectable PSA. Radiological features and serum PSA could be combined to better predict survival. PSA at 24 weeks showed strongest associations with overall survival, although a PSA concentration of 0·2 ng/mL or less at any timepoint predicted favourable outcome. These findings could inform prognosis and warrant evaluation for treatment selection in clinical trials. FUNDING:Cancer Research UK, Prostate Cancer UK, UK Medical Research Council, and John Black Charitable Foundation.

OBJECTIVES:Patients with homologous recombination repair gene altered (HRR+) metastatic castration-resistant prostate cancer (mCRPC) have a poor prognosis but achieved clinical benefits when treated with first-line niraparib and abiraterone acetate plus prednisone (niraparib + AAP) in the MAGNITUDE trial. We report final exploratory results from MAGNITUDE for the subgroup of patients with Breast Cancer gene-positive (BRCA+) mCRPC enrolled in Asia (NCT03748641). METHODS:Participants with HRR + mCRPC were randomized 1:1 to treatment with niraparib + AAP or placebo + AAP. The primary endpoint of radiographic progression-free survival (rPFS) by blinded independent central review (BICR) and secondary survival endpoints were calculated for the BRCA+ Asian subgroup. Safety was assessed in the Asian HRR+ population. RESULTS:The Asian subgroup included 35 participants with BRCA + mCRPC (all BRCA2+). After 34.99 months of follow-up, median rPFS by BICR was 38.6 months in the niraparib + AAP group versus 8.3 months in the placebo+AAP group (hazard ratio [HR] 0.33, 95% confidence interval [CI] 0.13-0.83, nominal p-value = 0.0141). Clinically relevant benefits were also observed in time to PSA progression (HR 0.32, 95% CI 0.13-0.83), and time to cytotoxic chemotherapy (HR 0.098, 95% CI 0.01-0.68). Median overall survival was not reached in the niraparib+AAP group and was 24.0 months in the placebo+AAP group (HR 0.67, 95% CI 0.27-1.71). The safety profile of niraparib+AAP was consistent with the main study population. CONCLUSIONS:In this final exploratory analysis of the Asian subgroup, participants with BRCA + mCRPC continued to benefit from first-line treatment with niraparib + AAP in comparison to placebo + AAP, with efficacy and toxicity profiles consistent with the global study population. TRIAL REGISTRATION:United States National Library of Medicine (https://clinicaltrials.gov); NCT03748641.

BACKGROUND:Effective prognostication improves selection of patients with prostate cancer for treatment combinations. We aimed to evaluate whether a previously developed multimodal artificial intelligence (MMAI) algorithm was prognostic in very advanced prostate cancer using data from four phase 3 trials of the STAMPEDE platform protocol. METHODS:We included patients starting androgen-deprivation therapy in the docetaxel, docetaxel plus zoledronic acid, abiraterone, or abiraterone plus enzalutamide trials. Patients were recruited at 112 sites. We combined all standard-of-care control patients (including those allocated to standard of care [SOC-ADT] consisting of testosterone suppression with luteinising hormone-releasing hormone agonists or antagonists, and radiotherapy when indicated), and we combined the rest of the patients into docetaxel-treated or abiraterone-treated groups. Patients had either metastatic disease or were at very high-risk of metastatic disease, determined by node-positivity or, if node-negative, by T stage, serum prostate-specific antigen (PSA) level, and Gleason score. We used the locked ArteraAI Prostate MMAI algorithm that combined these clinical variables, age, and digitised prostate biopsy pathology images. We performed Fine-Gray and Cox regression adjusted for treatment allocation and cumulative incidence analyses at 5 years to evaluate associations with prostate cancer-specific mortality (PCSM) for continuous (per SD increase) and categorical (quartile-Q) scores. The STAMPEDE platform protocol is registered with ClinicalTrials.gov, NCT00268476. FINDINGS:Of 5213 eligible patients recruited from Oct 5, 2005, to March 31, 2016, 3167 were included in this analysis (1575 [49·7%] with non-metastatic disease, 1592 [50·3%] with metastatic disease; median follow-up 6·9 years [IQR 5·9-8·0]) with all datapoints available for score generation. The MMAI algorithm (per SD increase) was strongly associated with PCSM (hazard ratio [HR] 1·40, 95% CI 1·30-1·51, p<0·0001). On ad-hoc inspection, the highest scoring quartile of patients in each disease and treatment allocation group (MMAI Q4; vs the bottom three quartiles, Q1-3) had the highest PCSM risk in both patients with non-metastatic disease (HR 2·12, 1·61-2·81, p<0·0001) and those with metastatic disease (HR 1·62, 1·39-1·88, p<0·0001). MMAI quartile stratification split patients categorised by disease burden into groups with notably different risks of 5-year PCSM: patients with non-metastatic disease that were node-negative could be further stratified by MMAI score quartile Q1-3 (3%, 2-4) versus Q4 (11%, 7-15), those with non-metastatic disease that were node-positive could be stratified by Q1-3 (11%, 8-14) versus Q4 (20%, 13-26), those with metastatic disease with low-volume could be stratified by Q1-3 (27%, 23-31) versus Q4 (43%, 36-51), and those with metastatic disease with high-volume could be stratified by Q1-3 (48%, 44-52) versus Q4 (68%, 62-75). INTERPRETATION:Diagnostic prostate biopsy samples contain prognostic information in patients with, or at high-risk of, radiologically overt metastatic prostate cancer. MMAI algorithm combined with disease burden improves prognostication of advanced prostate cancer. FUNDING:Prostate Cancer UK, UK Medical Research Council, Cancer Research UK, John Black Charitable Foundation, Prostate Cancer Foundation, Sanofi Aventis, Janssen, Astellas, Novartis, Artera.

BACKGROUND:Older men with metastatic hormone-sensitive prostate cancer (mHSPC) are more likely to have comorbid medical conditions and die from causes other than prostate cancer. We aimed to determine if age impacts the overall survival (OS) benefit from systemic treatment intensification (TI) with androgen receptor pathway inhibitors (ARPIs) and/or chemotherapy in mHSPC. METHODS:A systematic literature search in MEDLINE, Embase, and conference proceedings was conducted to identify randomized phase 3 trials in mHSPC evaluating the role of TI between January 1, 2010, and January 1, 2024. Age was dichotomized as 70 years or older in all trials, except as 75 years or older in one trial. Meta-analyses were performed with random-effects modeling. Meta-regression was performed using Hartung-Knapp methods. Individual patient data (IPD) from three trials (TITAN, ARASENS, and LATITUDE) were used to validate the aggregate meta-analysis. RESULTS:Eleven randomized comparisons (n=13,648 patients; 8324 younger men and 5162 older men) were included in the aggregate meta-analysis. Overall, TI was associated with improved OS (hazard ratio, 0.73; 95% confidence interval [CI], 0.68 to 0.78). There was an interaction between age and TI on OS (P-interaction <0.001; younger men: hazard ratio, 0.63; 95% CI, 0.56 to 0.70; older men: hazard ratio, 0.82; 95% CI, 0.74 to 0.90). TI was not associated with improvement in OS in older men treated in trials utilizing predominantly triplet therapy (hazard ratio, 0.94; 95% CI, 0.77 to 1.14). These results were similar in the IPD analysis. In the IPD analysis, ARPI addition was associated with improved OS in men 70 years or older with high-volume synchronous disease (hazard ratio, 0.83; 95% CI, 0.70 to 0.99), but not in low-volume synchronous disease (hazard ratio, 0.89; 95% CI, 0.61 to 1.30). CONCLUSIONS:We observed an interaction between age and systemic TI on OS for men with mHSPC. Our data provide information on potential treatment strategies for men 70 years or older, especially in low-volume synchronous disease, where radiotherapy to the primary site is the standard of care. (Funded by the National Institutes of Health and others.).