Channar, Aneeta

ABSTRACTBackgroundThe treatment landscape for multiple myeloma continues to evolve. Recently, the addition of anti‐CD38 monoclonal antibodies (mAbs) to the triplet regimen, comprising a proteasome inhibitor, an immunomodulatory agent, and a steroid, for transplant‐eligible newly diagnosed multiple myeloma (TENDMM) has shown promising results.AimsTo evaluate the overall efficacy and safety of quadruplet therapy with an anti‐CD38 mAb compared to a triplet regimen.MethodsA systematic search of Medline, Scopus, and EMBASE databases from inception to July 2024 identified relevant randomized controlled trials (RCTs). Efficacy and safety outcomes were derived using random‐effects meta‐analysis. Summarized outcomes include hazard ratios (HR) for progression‐free survival (PFS) and overall survival (OS), odds ratios (OR) for response rates, measurable residual disease (MRD) negativity rate, and grade 3 or higher adverse events (G ≥ 3 AEs).ResultsFive RCTs involving 2963 patients were included. A statistically significant PFS was observed for quadruplet therapy when compared to the triplet regimen (HR 0.44; 95% Confidence Interval [CI] 0.35–0.56). PFS benefit was consistent for the standard risk (SR) group (HR 0.38; 95% CI 0.27–0.52) and high risk (HiR) group (HR 0.62; 95% CI 0.41–0.92). No statistically significant benefit was observed for OS (HR 0.55; 95% CI 0.28–1.08). A statistically significant benefit was observed for the overall response rate (OR 1.77; 95% CI 1.02–3.06) and MRD negativity rate (OR 2.67; 95% CI 1.79–3.99). No significant differences were observed for G ≥ 3 AE (OR 1.21; 95% CI 0.92–1.58), lymphopenia (OR 1.09; 95% CI 0.62–1.89), and anemia (OR 1.06; 95% CI 0.83–1.37). However, a significantly increased risk was observed for all‐grade thrombocytopenia (OR 1.64; 95% CI 1.37–1.97), neutropenia (OR 2.24; 95% CI 1.67–3.02) and infections (OR 1.88; 95% CI 1.07–3.31).ConclusionQuadruplet therapy demonstrated a favorable efficacy and safety profile, with consistent benefit across subgroups. The findings support its potential as the new standard of care for TENDMM.

520 Background: The annual incidence of renal cancer is 0.02% among the general United States population. End stage renal disease (ESRD) and exposure to dialysis are thought to be the primary drivers of increased risk of renal cancer in renal transplant patients rather than immunosuppression. This has been evidenced by how the incidence of RCC in heart transplant recipients is no different than the normal population. In this study, we aim to characterize RCC incidence among kidney transplant patients (usually exposed to ESRD/dialysis) versus other solid organ transplant patients (usually unexposed to ESRD/dialysis). Methods: We used CPT codes to search for patients who had received a solid organ transplant (kidney, liver, heart, lung, pancreas) at all Mayo Clinic sites from 1/1/2018 to 1/1/2024. Within this cohort, we identified those who had been diagnosed with kidney cancer after initiating dialysis or receiving a transplant, and retrospectively extracted data related to demographics, cancer diagnosis, and transplant details. Results: We identified 10873 patients who had received a solid organ transplant (Table 1). Of these, 178 (1.76%) were diagnosed with kidney cancer after either starting dialysis or receiving a transplant. These 178 patients were of median age 56 years at time of cancer diagnosis (STD 12), 71% male, 70% white, 20% black, 4.5% Asian, 2.8% American Native. Of 5792 patients who had received a kidney transplant (with or without another solid organ transplant), 172 (2.97%) were diagnosed with kidney cancer after having started dialysis or receiving a kidney transplant. Of these 172, 156 (91%) were exposed to dialysis (107 primarily hemodialysis and 48 peritoneal). Of 4392 patients who had received a solid organ transplant other than kidney (liver, heart, lung, and/or pancreas), 6 (0.14%) were diagnosed with kidney cancer after having received a kidney transplant. Of these 6, none underwent dialysis. Conclusions: Patients with kidney transplants are at increased risk of kidney cancer compared to patients with non-kidney solid organ transplants (2.97% vs 0.14%). This supports prior evidence showing ESRD plays a significant role in the pathogenesis of kidney cancer. Patients who received solid organ transplants at Mayo Clinic from 2018-2024 and were subsequently diagnosed with kidney cancer. n % With RCC after TXP 178 1.7587% Cancer Diagnosis after Kidney HD/TXP 172 2.9696% Cancer Diagnosis after Other TXP 6 0.1386% Patients who received solid organ transplants at Mayo Clinic from 2018-2024 n % Unique Patients 10121 100% Kidney Transplant 5792 57.23% Alone 5088 50.27% &Liver 332 3.28% &Heart 119 1.18% &Lung 8 0.08% &Pancreas 245 2.42% Non-kidney Transplant (Liver, Heart, Lung, or Pancreas) 4329 42.77% TXP: Transplant, HD: Hemodialysis.

428 Background: Prostate cancer management presents a significant healthcare burden, with the need to efficiently triage patients for treatment. Our objective is to leverage large language models to predict physician-recommended treatment plans from unstructured clinical notes. By accurately predicting treatment plans, we aim to risk stratify and triage patients effectively, thereby optimizing the allocation of physician resources. Methods: 448 unstructured initial urology consultation patient notes following first positive prostate cancer biopsy were identified. The recommended and final treatments received were manually annotated to establish ground truth labels (Table 1). The dataset was split 80:20 for training and testing, preprocessed to remove plan sections and formatted into question-answer (QA) format. A domain-specific large language model (LLM) inspired by GPT and a specialized tokenizer (PCa- LLM) for prostate cancer terminology were developed. QA models were built using the PCa-LLM and compared with those using GPT-2 as the backbone to predict recommended and final treatments. Results: For the physician-recommended treatment plans, our LLM (PCa-LLM) showed superior performance with higher AUROC scores for curative vs. non-curative treatments (0.78 vs. 0.65), chemo-hormonal vs. other non-curative treatments (0.89 vs. 0.65), and surveillance vs. all other treatments (0.72 vs. 0.70), while both models achieved the same high AUROC of 0.99 for chemo-hormonal vs. all other treatments. For final treatments, PCa-LLM demonstrated better AUROC for curative vs. non-curative treatments (0.77 vs. 0.74) and chemo-hormonal vs. other non-curative treatments (0.71 vs. 0.66), while GPT2 outperformed PCa-LLM for surveillance vs. all other treatments (0.78 vs. 0.70). Both models achieved an AUROC of 0.99 for chemo-hormonal vs. all other treatments. Conclusions: PCa-LLM accurately predicted most treatment categories better than GPT2, with higher AUROC scores, and can be utilized to triage prostate cancer patients using initial consultation notes. Task Physician -Recommended Treatment Plan Final Treatment Received Curative Prostatectomy/Radiation 228 230 Non-Curative Focal Therapy 22 15 Active Surveillance 40 45 Chemo-hormonal 30 30 Model Predictions (AUROC) GPT2 PCa-LLM GPT2 PCa-LLM Curative vs. non-curative 0.65 0.78 0.74 0.77 Chemohormonal vs. other non-curative 0.65 0.89 0.66 0.71 Chemohormonal vs. all other 0.99 0.99 0.99 0.99 Surveillance vs. other non-curative 0.64 0.60 0.67 0.59 Surveillance vs. all other 0.70 0.72 0.78 0.70

e19534 Background: Immunomodulatory drugs, proteasome inhibitors plus dexamethasone are the standard triplet induction regimen for TENDMM. We analyzed the efficacy of adding either anti-CD38 monoclonal antibodies (mAbs) or anti-SLAMF7 antibody to the triplet therapy. Methods: Ovid MEDLINE, EMBASE and published abstracts were systematically searched from each database’s inception through 01-31-2024 to identify II/III trials assessing quadruplet therapy versus triplet therapy in TENDMM patients. Hazard ratios (HR) for progression-free survival (PFS) and overall survival (OS), odds ratios (OR) for overall response rates (ORR), measurable residual disease (MRD) negativity rate (with sensitivity of 10 -5) and grade 3 or higher treatment-related adverse events (G≥3 TRAE) were summarized using random effects meta-analysis via inverse variance approach. Additional subgroup analyses based on the cytogenetic risk were performed. P-value of interaction (Pint ) < 0.1 was pre-specified as statistically significant for the difference between the two groups. Results: 3806 studies were screened and seven trials were included with a total of 3546 patients. Four trials (2303 patients) assessed the addition of anti-CD-38 mAbs and three (1243 patients) assessed anti-SLAMF7 mAb, elotuzumab to the triplet regimen. Quadruplet therapy significantly improved PFS as compared to triplet (HR: 0.63; 95% CI: 0.43-0.92), and the PFS benefit was also observed in standard risk group (HR 0.5; 95% CI 0.2-0.9); however, results were insignificant for high-risk group (HR 0.8; 95% CI 0.62-1.93). No significant OS benefit was observed (HR: 0.79; 95% CI 0.49–1.26); however, data for three trials (CASSIOPEIA, DSMM XVII, PERSEUS) is immature, with longer-term follow-up ongoing. Quadruplet therapy showed significant results for very good partial response or better (OR: 1.7; 95% CI 1.2-2.36), stringent complete response (OR: 1.74; 95% CI 1.27-2.07) and complete response or better (OR: 1.91; 95% CI 1.19-3.06). MRD rate shows benefit with quadruplet therapy (OR: 2.59; 95% CI 2.22-3.01). Improved MRD rate was also observed for high-risk (OR 2.13; 95% CI 1.4-3.2) and standard-risk group (OR 2.58; 95% CI 1.68-3.94). Secondary analysis for efficacy of anti-CD38 mAbs showed benefit for PFS (HR: 0.44; 95% CI: 0.35-0.56), ORR (OR: 1.77;95% CI: 1.02-3.06), and MRD (OR: 2.98; 95% CI 1.8-4.8). G ≥3 TRAE did not significantly differ between the groups (OR: 1.05; 95% CI 0.97-1.12). However, quadruplet therapy showed significant risk of infection (OR: 1.2; 95% 1.05-1.35) and thrombocytopenia (OR: 1.41; 95% CI 1.24-1.59). Conclusions: Quadruplet therapy improved PFS, ORR, and MRD rates compared to triplet regimen and has demonstrated promising benefits to be considered the new standard of care for TENDMM patients.

e16579 Background: Recent results from EV 302 and CheckMate 901 have transformed the treatment landscape of untreated locally advanced/metastatic urothelial cancer (Ia/mUC). Here, we present the most up-to-date evidence of comparative efficacy and safety of first line (1L) treatment options in Ia/mUC with emphasis on Enfortumab vedotin (EV)-pembrolizumab (P) and gemcitabine (Gem)-cisplatin (Cis)-nivolumab (N). Methods: This living systematic review used the living interactive evidence (LIvE) synthesis framework. Full-text and abstract publications of phase II/III randomized clinical trials comparing 1L immunotherapy combined with chemotherapy (IO+C) or immunotherapy alone (IO) regimens with platinum-based chemotherapy (Plat) in Ia/mUC were included. Outcomes of interest included overall survival (OS), progression-free survival (PFS) and treatment-related grade 3 or greater adverse events (≥G3 TRAE). Mixed treatment comparisons were made using network meta-analysis. P-scores were computed to assess relative treatment rankings. Results: A total of 5 trials (8 references) with 4,749 patients and 9 unique treatments were included. EV-P and Gem-Cis-N were ranked first and second in terms of OS and PFS improvement. EV-P improved OS compared to Gem-Cis-N (HR: 0.60; 0.45-0.81), Gem-Plat-atezolizumab(A) (0.55; 0.42-0.72), durvalumab(D)- tremelimumab(T) (0.55; 0.42-0.72), Gem-Plat-P (0.55; 0.42-0.72), P (0.51; 0.39-0.68), D (0.47; 0.36-0.63), A (0.48; 0.36-0.63) and Gem-Plat (0.47; 0.38-0.58). EV-P also improved PFS compared to Gem-Cis-N (0.63; 0.48-0.82), Gem-Plat-A (0.55; 0.43-0.69), D-T (0.42; 0.33-0.53), Gem-Plat-P (0.58; 0.45-0.74), P (0.34; 0.26-0.44), D (0.35; 0.27-0.44) and Gem-Plat (0.45; 0.38- 0.54). For ≥G3 TRAE, A was ranked first with the lowest adverse events compared to others. EV-P (rank 5) had significantly fewer events compared to Gem-Plat, Gem-Plat-A, Gem-Cis-N and Gem-Plat-P. Gem-Cis-N was ranked last with significantly greater events compared to A, P, D, D-T, Gem-Plat, EV-P, and Gem-Plat-A (Table with ranks [p-scores]). Conclusions: Current evidence suggests that patients with untreated la/mUC experience improved survival and slower disease progression with EV-P when compared to other contemporary options. Gem-Cis-N may be a reasonable alternative in patients who are cisplatin-eligible. Cost and access to these treatments are crucial and should be considered to facilitate shared decision making. [Table: see text]

98 Background: The risk of secondary primary malignancies (SPM) among the survivors of GU cancer is not well-established. In this study, we attempt to describe the patterns of SPMs in patients diagnosed with GU cancers. Methods: The Surveillance, Epidemiology, and End Results (SEER) database (SEER*Stat 8.4.2) was searched to obtain data on the incidence of SPM in adult patients (age >18 years) diagnosed with GU cancers, including prostate, renal, and bladder cancer. Standardized incidence ratios (SIRs) with a 95% confidence interval (CI) were calculated. SIR was defined as the observed SPMS from each category divided by the expected number of SPMs in the age-matched US population for the same period. The data was further stratified by age (<50y, 50-70y, >70y), race (White, Black, Asian/Pacific Islander), ethnicity (Hispanic, non-Hispanic), chemotherapy, and radiotherapy exposure. Results: A total of 1,041,217 patients were included in this analysis. In patients diagnosed with GU cancer, the incidence of overall SPM was 11%. Particularly, patients with GU cancers were observed to have a high incidence of Endocrine system SPM (1.52; 1.45-1.59), and urinary system SPM (1.51; 1.49-1.53) These results were consistent by different sociodemographic groups. In patients diagnosed with prostate cancer, the incidence of thyroid SPM was increased (1.31; 1.23-1.39). Particularly, prostate cancer patients treated with radiation therapy had increased incidence rates of SPM in the peritoneum, omentum and mesentery (1.57; 0.79-2.81) and urinary bladder (1.36;1.32-1.40) was higher as compared to those with no exposure to radiation therapy (1.11;1.08-1.13 and 1.03;1-1.06 respectively). Bladder cancer patients had an overall increased incidence of SPM in the esophagus (1.21; 1.08-1.35), lung, bronchus, trachea, and other respiratory organs (1.97;1.92-2.01), prostate (3.50;3.4-3.6) and kidney (1.86;1.76-1.97). A higher incidence of renal pelvis, ureter and other urinary organ SPM (11.08;10.48-11.07) was also notable in this population. Similarly, kidney cancer patients had a higher incidence of the endocrine system (3.00;2.74-3.27), prostate (1.24;1.2-1.29) and bladder 1.78;1.68-1.79 SPMs. Conclusions: This population-based study shows an increased risk of SPM development in GU cancer survivors compared to the general population. Clinicians should keep a high index of suspicion for SPMs and initiate appropriate workups at early warning signs.

643 Background: The FDA approval of enfortumab (EV) and pembrolizumab (Pembro) combination therapy as a first-line treatment for cisplatin-ineligible patients with locally advanced/metastatic urothelial carcinoma (la/mUC) was based on the EV-103 trial. We aim to assess the clinical response rate of this combination therapy in our institution's patients with locally advanced and metastatic UC. Methods: This retrospective cohort study included 20 patients diagnosed with locally advanced/metastatic UC(la/mUC) who were treated with EV-Pembro combination for at least 2 cycles, from June 2022 to August 2023 at the Mayo Clinic. Patients who were treatment naïve or who progressed one or more lines of therapy were included in the study cohort. Main outcome of interest included imaging-based best overall response rate in terms of complete (CR) and partial (PR) response, stable disease (SD), and progressive disease (PD). Results: Out of 20 patients, the number of males and females were 16 (80%) and 4 (20%) respectively; the median age was 77 years (IQR: 51-92). 3 (15%) of patients had involvement of upper urinary tract disease along with bladder cancer. The common sites of visceral metastasis at the time of initial presentation include liver 2(10%), lung 6(30%) and lymph nodes12(60%). Common toxicities of this regimen included rash, pruritis, peripheral neuropathy, fatigue, transaminitis, dysgeusia, and diarrhea. The treatment was stopped in 10 (50%) patients due to completion of planned therapy (achieved CR or proceeded with resection of residual disease) (30%), 5 patients due to progression (50%), 1 patient due to therapy side effects (10%) and in 1 patient due to death (10%). The objective response was 45% (N =9); 5 (25%) had PR, and 4 (20%) had CR. A total of 2 (10%) had SD while 2 (10%) experienced PD. Histological correlation with clinical benefit is shown in the table. Conclusions: EV-Pembro combination therapy shows promising responses in patients who have progressed after previous lines of therapy, consistent with previously published data on EV 201 in small cohorts. However, ongoing expansion of this cohort and data from larger studies will help further elucidate survival benefits and their correlation with genetic testing. [Table: see text]

173 Background: The data for combining PARPi and ARPi in mCRPC have shown conflicting results. Here, we report a quantitative summary of benefits by clinically meaningful subgroups (HRR mutation status, BRCA mutation status) to guide the use of PARPi and ARPi combination in mCRPC setting. Methods: MEDLINE, EMBASE, and CENTRAL were systematically searched from each database’s inception through September 7, 2023. Phase III studies comparing PARPi + ARPi with ARPi + placebo in mCRPC were included. Radiographic progression-free survival (rPFS) and overall survival (OS) in patient subgroups based on HRR and BRCA mutation status were assessed. Hazard ratios for rPFS and OS with 95% CI were collected at the level of each trial, and a random-effects meta-analysis was conducted using an inverse variance approach. Subgroup differences were assessed and p-value of interaction <0.1 was considered statistically significant. Results: The literature search identified 4976 studies from which 3 trials (11 references) – TALAPRO2, PROpel and MAGNITUDE met the inclusion criteria. A total of 2254 participants were eligible for analysis. PARPi + ARPi prolonged rPFS in patients with HRR mutations (HR: 0.55, 95%CI: 0.38-0.78) as well as in patients without HRR mutations (HR: 0.74, 95%CI: 0.63-0.88). There is no evidence of treatment interaction by HRR mutation status (p = 0.14). In patients harboring HRR mutations, improved rPFS was observed in those with BRCA mutations (HR: 0.28, 95%CI: 0.13-0.62) as well as those without BRCA mutations (HR: 0.72, 95%CI: 0.59-0.87). However, there is evidence that patients with BRCA mutations derived greater rPFS benefit as compared to patients without BRCA mutations (p =0.02). PARPi + ARPi showed no significant improvement in overall survival either in patients with HRR mutations (HR: 0.79, 95%CI: 0.59-1.05) or in patients without HRR mutations (HR: 0.92, 95%CI: 0.74-1.14). Conclusions: Genomic testing for HRR genes is mandatory to guide clinical decision making in mCRPC patients. Patients harboring BRCA mutations are most likely to derive clinically meaningful benefit from combination PARPi + ARPi treatment. [Table: see text]