Barker, Kenneth N.

e16502 Background: Accurate postoperative risk stratification in localized clear-cell renal cell carcinoma (ccRCC) informs prognosis, surveillance intensity, and eligibility for adjuvant systemic therapy. Although validated prognostic models (Leibovich 2018, SSIGN, and UISS) exist, they are inconsistently applied in routine practice due to workflow and documentation barriers. Using AI assisted tools within the electronic medical record (EMR) may enable rapid, standardized risk assessment and improve clinical use. Methods: We retrospectively analyzed 92 patients with localized ccRCC undergoing radical nephrectomy and postoperative oncology evaluation (December 2021–September 2025) across three Mayo Clinic sites. Pathology reports and oncology notes were extracted via structured SQL queries. Clinical and pathologic variables were parsed using a zero-shot GPT-4o pipeline. Gold-standard prognostic risk classification and adjuvant therapy eligibility were established by an expert oncology clinician using validated prognostic calculators and KEYNOTE-564 eligibility criteria. AI-generated outputs and novice manual abstraction by two first-year fellows were compared against expert assessment using accuracy, precision, recall, and F1 score. Leibovich and SSIGN were evaluated as three-class models (low/intermediate/high), and UISS as binary risk stratification (high vs non-high). Results: Among 92 patients with localized ccRCC (median age 64 years [range 41–78]), AI-generated outputs demonstrated near-perfect agreement with expert assessment for KEYNOTE-564 adjuvant immunotherapy eligibility (accuracy 97%, precision 100%, recall 97%, F1 score 98%). For three-class prognostic stratification, AI achieved perfect agreement for Leibovich disease-free survival risk (accuracy, precision, recall, and F1 all 100%), outperforming novice abstraction. For SSIGN, AI demonstrated strong multi-class performance (accuracy 91%, precision 91%, recall 93%, F1 score 92%), compared with novice abstraction (accuracy 92%, F1 score 90%). For binary UISS risk stratification, AI achieved 81% accuracy, precision 74%, recall 100%, and F1 score 85% showing a tendency towards false positives. Conclusions: This study demonstrates AI can use existing prognostic and systemic therapy eligibility to accurately risk stratify and identify patients eligible for adjuvant systemic immunotherapy post nephrectomy. For our next steps, we plan to develop a multimodal AI platform integrating pathologic, radiologic, and clinical data to improve prognostication for outcomes and predictive capabilities for patients who would benefit from adjuvant systemic therapy for more personalized medicine.

127 Background: Bone metastases affect up to 90 % of patients with metastatic hormone-resistant prostate cancer (mHRPC) and cause substantial morbidity from skeletal-related events (SREs) such as fracture, spinal-cord compression, and palliative interventions. Bone-modifying agents (BMAs) including bisphosphonates and denosumab reduce SRE risk and are NCCN-recommended, however, real-world use remains inconsistent. Methods: Patients with mHRPC treated from January 2017-September 2024 across Mayo Clinic sites were identified using SQL-based EHR queries confirmed by manual chart review. Bone Metastases were detected through keyword searchers of radiology reports and confirmed through manual chart review. SRE-prevention dosing was defined as zoledronic acid 4mg IV or denosumab 120mg SC; osteoporosis dosing was excluded. SREs were identified using diagnosis codes and text-pattern searches for radiotherapy, surgery, fracture, and spinal-cord compression. Descriptive statistics summarized BMA utilization and SRE incidence. Categorical variables were compared using Chi-square tests, and a risk ratio (RR) with 95% confidence intervals was calculated to evaluate association between early BMA initiation and SRE risk. Results: Among 778 patients with mHRPC, 685 (88 %) had bone metastases (mean age 70.5 years). Of these, 169 (24.7 %) had an SRE, and 261 (38.1 %) received BMAs at SRE-prevention doses (denosumab n = 157 [60 %]; zoledronic acid n = 104 [40 %]). Based on a chi-square test, combined SRE incidence did not differ significantly (No BMA 23 %, denosumab 23 %, zoledronic 33 %; p = 0.069). Bone pain at baseline was more common in patients who later received a BMA (136 [68 %]) than in those who did not (82 [41 %]; p < 0.001). Among 200 randomly sampled non-BMA patients, 83 had no recorded BMA discussion (66 also lacked bone pain), 38 lacked dental clearance, 32 had uncompleted plans and 18 declined therapy. Early BMA initiation (before first bone metastases) was associated with fewer SREs (16 % vs 29 %; RR 0.56, 95 % CI 0.33–0.96). Conclusions: Less than half of bone-metastatic mHRPC patients received BMAs. Non-initiation was often linked to modifiable factors such as delayed dental clearance or lack of treatment discussions, highlighting the need for system-level strategies to improve timely bone-directed care. SREs were common, affecting one quarter of patients. Small sample size precluded meaningful comparison of the impact of BMAs on SRE incidence however early BMA initiation may lower SREs. Incidence of SREs stratified by no BMA vs BMA treatment. SRE No BMA BMA Overall Pathological Fracture 6.4% (27/424) 4.9% (13/261) 5.8% (40/685) Radiotherapy to Bone 13.9% (59/424) 18.8% (49/261) 15.7% (108/685) Spinal Cord Compression 0.7% (3/424) 3.1% (8/261) 1.6% (11/685) Surgery to Bone 2.1% (9/424) 0.3% (1/261) 1.5% (10/685) Combined 23% (98/424) 27.2% (71/261) 24.7% (169/685)

483 Background: Sarcomatoid dedifferentiation (sRCC) in metastatic clear-cell renal cell carcinoma (mccRCC) confers aggressive disease and poor prognosis. We maintain a living meta-analysis of first-line immune checkpoint inhibitor (ICI)–based combinations in mccRCC (Riaz et al., Eur Urol Oncol 2021), which demonstrated improved survival with ICI-based regimens over sunitinib. Here, we present an updated synthesis focused on the comparative efficacy of ICI combinations in the sarcomatoid subset. Methods: A systematic search of MEDLINE, EMBASE, and CENTRAL through October 2025 was performed as part of our living meta-analysis of first-line mccRCC therapy. Eligible phase III RCTs compared ICI combinations (IO/IO or IO/TKI) versus sunitinib, including CheckMate 214, CheckMate 9ER, KEYNOTE-426, CLEAR/KEYNOTE-581, JAVELIN Renal 101, and IMmotion151. Extracted outcomes included overall (OS) and progression-free survival (PFS), and objective (ORR), complete (CR), and partial (PR) response rates. Random-effects meta-analyses generated pooled hazard ratios (HRs) for time-to-event outcomes and risk ratios (RRs) for response rates with 95% confidence intervals. Subgroup interaction analyses compared sarcomatoid versus non-sarcomatoid subgroups, with p < 0.1 considered significant. Results: Six phase III RCTs (n = 5,121; 624 sarcomatoid) were included. Across all ICI-based combinations, ICI therapy improved outcomes versus sunitinib in both sarcomatoid and non-sarcomatoid disease. In the pooled analysis, the OS interaction favored sRCC meeting the prespecified significance threshold for subgroup analyses (HR 0.53 vs 0.68; p-interaction = 0.06 < 0.10), while no significant interaction was seen for PFS. Response outcomes showed the strongest differential benefit, particularly with IO/TKI regimens. IO/IO results were directionally consistent but limited by smaller non-sarcomatoid samples. Conclusions: ICI-based combinations significantly improve survival and response outcomes versus sunitinib in mccRCC. Using a prespecified α = 0.10 for interaction testing, the pooled analysis showed a significant OS interaction and higher response rates in sRCC, indicating enhanced ICI sensitivity. These updated meta-analysis data support ICI regimens as the preferred first-line therapy for mRCC with sarcomatoid de-differentiation. Endpoint Regimen Subgroup (S = sarcomatoid; NS = non-sarcomatoid) Effect (95% CI) p-interaction PFS IO/IO S 0.51 (0.40–0.65) – IO/TKI S vs NS 0.48 (0.36–0.64) vs 0.46 (0.39–0.52) 0.81 OS IO/IO S 0.54 (0.07–4.42) – IO/TKI S vs NS 0.51 (0.17–1.48) vs 0.68 (0.30–1.58) 0.24 ORR IO/IO S 2.93 (0.49–17.37) – IO/TKI S vs NS 2.43 (1.84–3.21) vs 1.95 (1.67–2.28) 0.03 CR IO/IO S 3.81 (0.82–17.71) – IO/TKI S vs NS 5.93 (4.73–7.42) vs 2.85 (0.10–83.73) 0.007 PR IO/IO S 3.48 (1.70–7.11) – IO/TKI S vs NS 2.10 (1.78–2.47) vs 1.75 (1.18–2.61) <0.001

e17159 Background: Socioeconomic inequality (SI) is a recognized risk factor for negative outcomes in prostate cancer (PCa), influenced by biology, healthcare access, and lifestyle. This study aims to explore the molecular impact of SI on PCa, focusing on targetable and prognostic biomarkers. Methods: We conducted a retrospective analysis of 100 metastatic hormone-sensitive PCa patients (2016-2023), with 97 undergoing next-generation sequencing (NGS). We examined only pathogenic variants alongside clinical variables. The Area Deprivation Index (ADI) assessed neighborhood SI, with higher scores indicating greater disadvantage. Patients were divided into tertiles. Chi-square and Fisher’s exact tests evaluated the relationships between tertiles and genomic alterations, while ordinal logistic regression analyzed outcomes by various stratifications. Results: Of the 97 patients, 29 were in tertile 1, 34 in tertile 2, and 35 in tertile 3. Tertile 1 had a significantly higher percentage of non-Hispanic patients (90%) compared to tertile 2 (62%) and tertile 3 (37%), p=0.0001. Other demographic factors, such as age, comorbidities, and cancer history, showed no significant differences by tertile. Median PSA levels increased from tertile 1 (22 ng/mL) to tertile 3 (95 ng/mL), although this was not statistically significant (p=0.14). Tumor volume and visceral metastasis were notably higher in tertile 3 (p=0.029 and p=0.02). BRCA1/2 mutations were more prevalent in tertile 3 (11%, p=0.03) via liquid biopsy compared to tertiles 1 and 2 (0%). TMPRSS2-ERG fusion mutations were significantly more common in tertile 3 (66.6%) compared to tertile 2 (19.1%) and tertile 1 (14.2%), p=0.009. The association between ADI tertile and TMPRSS2 approached significance when controlled for ethnicity (p=0.061), with Hispanic ethnicity having 3.5 times the odds of the fusion compared to non-Hispanics (p=0.02). Tertile 1 patients were more associated with receiving progressive therapy lines (2L p=0.01, 3L p=0.03, 4L p=0.04), but median time to subsequent treatment at 5 years was similar across tertiles (p=0.84). Conclusions: Higher SI was linked to increased PSA, tumor volume, visceral metastasis risk, and higher prevalence of BRCA1/2 and TMPRSS2-ERG mutations. This study highlights the need for further research on the molecular impacts of SI on adverse PCa outcomes, particularly among Hispanic populations.

Abstract Background: Bladder cancer patients with lower socioeconomic status (SES) often present with more aggressive disease and face poor outcomes, likely due to complex interactions with risk factors linked to lower SES. However, little is known about the effect of low SES on bladder tumor biology at the molecular level. This study sought to characterize better the impact of low SES on the bladder tumor microenvironment. Methods: This is a retrospective analysis of 93 patients (63 male and 30 female) ranging from age 33 to 92 presenting to the University of Arizona Cancer Center with bladder cancer from 2016-2023. Each patient's neighborhood level of SES was scored using the Area Deprivation Index on a scale of 1-100, with 1 representing the highest SES and 100 the least. These patients were then split into tertile 1: 1-33 (T1: N=16), tertile 2: 34-67 (T2: N=43), and tertile 3: 68-100 (T3: N=34), and each patient’s tumor microenvironment and mutational landscape was characterized and compared utilizing NGS (592, NextSeq; WES, NovaSeq) and WTS Sequencing (NovaSeq) (Caris Life Sciences, Phoenix, AZ). Statistical significance was determined using chi-square and Mann-Whitney U (p&lt;0.05). Results: Our study had no significant difference between age, sex, and race between the three tertiles. Hispanic ethnicity was significantly higher in T3 (26.5%) when compared to T2 (7%) and T1 (0%), p=0.013. The frequency of TMB-H (&gt;10 mutations/megabase) was significantly lower in T3 (15.6%) when compared to T2 (51.2%, p=0.02) and T1 (50%, p=0.01). There was significantly less T cell CD8+ infiltration in tertile 3 (0.02%) when compared to T2 (0.43%, p=0.04) and T1 (0.37%, p=0.08), and less dendritic cell infiltration in T3 (0%) when compared to T2 (0.1%, p=0.13) and T1 (0.64%, p=0.008). T regulatory cells were lower in T3 (1.37%) compared to T2 (2.13%, p=0.09) and T3 (2.02%, p=0.24). IHC-PD-L1 and gene expression for immune checkpoint genes, MHC-Class I, and MHC-Class II did not vary significantly between tertiles. KMT2C-mt was highest in T2 (21.1%) compared to T1 (3.12%, p=0.03) and T3 (6.67%). There was no other significant differences in mutation prevalence between the three tertiles. Discussion: In our study, lower SES bladder cancer patients had a lower amount of CD8+ cells, dendritic cell infiltration, and a low frequency of TMB-H, indicating a lower level of adaptive immune response present in the tumor microenvironment. Lower levels of adaptive immune activity have been associated with more aggressive tumor behavior and worse outcomes in bladder cancer patients. These findings provide a partial explanation of the molecular mechanisms underlying the poor prognosis observed in low SES patients with bladder cancer. Larger-scale studies exploring the impact of SES on tumor biology are essential as they hold significant therapeutic and preventive implications. Citation Format: Tom Marco, Kenneth Barker, Jesse Ritter, Numaan Mahmood, Rishab Srivastava, Amith Rao, Isaac Zarif, Ricardo Estrada Mendizabal, Sachin Deshmukh, Edgar Tapia, Jose Guillen-Rodriguez, Juan Chipollini, Alejandro Recio-Boiles. The effects of socioeconomic deprivation on the tumor microenvironment of bladder cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2025; Part 1 (Regular Abstracts); 2025 Apr 25-30; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2025;85(8_Suppl_1):Abstract nr 7392.

Abstract Background: Hispanic American (HA) men with prostate cancer (PC) are more likely to have more aggressive and advanced diseases and greater mortality rates compared to non-Hispanic white (NHW) men. Resistance to the current anticancer therapy is the major hurdle that leads to poor clinical outcomes. Hedgehog, Notch, and Wnt signaling pathways play a crucial role in development, progression, and resistance to the various anticancer therapies. Here, we characterized the enrichment of Hedgehog, Notch, and Wnt signaling pathways and molecular tumors differences between HA and NHW patients. Methods: Our data consist of 88 PC tumors samples (HA=34, NHW=54) obtained from treatment-naive metastatic hormone-sensitive prostate cancer (mHSPC) that were analyzed by next-generation sequencing (592, NextSeq; Whole Exome Sequencing, NovaSeq) and Whole Transcriptome Sequencing (WTS; NovaSeq) (Caris Life Sciences, Phoenix, AZ). Pathway enrichment was determined by Gene Set Enrichment Analysis (GSEA, Broad Institute) by measurable TPM (transcripts per kilobase million). The medical records were reviewed in a deidentified fashion for clinical features. Statistical significance was determined using chi-square and Mann-Whitney U (p&lt;0.05). Results: HA PC had enrichment of Hedgehog signaling (NES: 1.45, FDR=0.04), Notch signaling (NES: 1.41, FDR=0.07), and Wnt/β-catenin signaling (NES: 1.38, FDR=0.11) pathways compared to NHW tumors. HA tumors had higher expression of genes (HES1, Notch1, WNT1, WNT2; FC:1.1-2.5) associated with crosstalk between Hedgehog, Notch, and Wnt/β- catenin signaling pathways (all p&lt;0.05). Moreover, HA tumors had higher expression of stemness (ALDH1A2, ALDH1A1, PROM1; FC: 1.7-3.0), drug efflux (ABCC1, ABCB1; FC: 1.1- 1.5), epithelial to mesenchymal transition (EMT) (TWIST1, MMP2; FC: 1.1-1.5), cell cycle (CCND2; FC: 1.2), inhibition of apoptosis (BIRC2, XIAP; FC: 1.1) and epigenetic (EP300, TET1, TET2; FC: 1.3-1.4) related genes compared to NHW tumors (all p&lt;0.05). HA PC had higher frequency of Hedgehog and Wnt/β-catenin associated SPOP (16% vs 6.6%, p=0.2) and CTNNB1 (12% vs 2.2%, p=0.1) mutation compared to NHW PC. Conclusion: These results demonstrate that tumors from HA patients had enrichment of oncogenic Hedgehog, Notch, and Wnt/β-catenin signaling pathways, higher expression of stemness, drug efflux, EMT, cell cycle, inhibition of apoptosis and epigenetic-related genes, and mutations directly involved in activating the Hedgehog and Wnt/β-catenin signaling pathways. Together, these findings suggest that tumors from HA patients are enriched for gene signatures that promote cancer progression and therapy resistance. Additional research on collaboration and crosstalk between Hedgehog, Notch, and Wnt/β-catenin signaling pathways may help in designing better therapeutic strategies for HA men with mHSPC. Citation Format: Alejandro Recio-Boiles, Sachin Kumar Deshmukh, Ricardo J. Estrada-Mendizabal, Kenneth Barker, Sharon Wu, Joanne Xiu, Milan Radovich, Elisabeth I. Heath, Rana McKay, Juan Chipollini, Cynthia K. Miranti. Defining the role of Hedgehog, Notch, and Wnt signaling pathways in aggressive lethal prostate cancer of Hispanic men [abstract]. In: Proceedings of the 17th AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2024 Sep 21-24; Los Angeles, CA. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2024;33(9 Suppl):Abstract nr C100.