Citations

e13635 Background: Melanoma is an aggressive skin malignancy with rising global incidence, for which checkpoint inhibitors (CPI) and BRAF-targeted therapies are standard of care in advanced disease. However, access to molecular diagnostics and CPI remains limited in conflict-affected regions such as Syria. Real-world data describing melanoma management in this setting are scarce. Methods: We conducted a retrospective study of all patients diagnosed with melanoma between 2022 and 2024 at Al-Bairouni University Hospital (ABUH), Syria’s primary oncology referral center. Demographic and clinical characteristics were analyzed for the entire cohort, and patients with advanced disease were evaluated for molecular testing and treatment patterns. Semi-structured interviews were conducted in a mixed advanced cancer subset (N = 35) to explore barriers to immunotherapy access. Results: Among 115 patients with melanoma, the median age at diagnosis was 57 years (IQR 44.5–67), and 54.7% were male. At presentation, 18.3% had stage I disease, 1.7% stage II, 2.6% stage III, and 40.9% stage IV disease; staging was unavailable in 36.5%. Among patients with advanced melanoma (n = 47), BRAF testing was performed in 17 (36.2%), with targeted therapy administered to 5/16 BRAF-positive patients. Only 7/47 patients (14.9%) received CPI, primarily as monotherapy. In the qualitative subset (predominantly lung cancer), five major barriers to immunotherapy access emerged: financial toxicity (n = 22), limited drug availability (n = 9), limited patient awareness (n = 8), geographic/logistical challenges (n = 5), and system delays (n = 4). Conclusions: Despite a substantial burden of advanced melanoma, access to molecular testing, targeted therapy and CPI in Syria remains limited. Qualitative findings highlight financial and structural barriers as primary drivers of limited access, underscoring the need for improved drug availability, diagnostic infrastructure, and patient education in conflict-affected settings.

e13615 Background: Bacillus Calmette-Guérin (BCG) remains the standard intravesical therapy for high-risk non-muscle-invasive bladder cancer (NMIBC), but weekly clinic-based instillations create substantial travel, time, and indirect costs that may threaten adherence. Therefore, we proposed a pilot trial of delivering BCG at Home as a prospective, single-center pilot testing a pharmacy-to-home pathway with digital patient-reported outcome (PRO) monitoring. Methods: BCG at Home is a prospective, single-center pilot evaluating feasibility and safety of home delivery of induction BCG for treatment-naïve, high-grade T1 and/or carcinoma in situ NMIBC. Dose 1 is administered in clinic to confirm tolerability and catheterization feasibility; doses 2-6 are administered at home by Penn Medicine at Home nurses after a 3 month training and proctorship program in intravesical therapy and exposure precautions. To enable transport beyond conventional short post-preparation windows, the pharmacy prepares BCG using a closed system transfer device (CSTD); bench testing demonstrated stability and sterility for 24 hours after connection. A medical courier delivers the prepared medication to the patient’s home, where the nurse receives the delivery and performs the instillation. The primary endpoint is induction adherence (completion of all recommended doses). Secondary endpoints include PROs (EORTC QLQ-C30/QLQ-NMIBC24), satisfaction, and acute care utilization. PROs are captured before and after treatment using a conversational chatbot; domain summaries are assessed at baseline, 6 weeks, and 12 weeks. Results: The pilot began enrollment in June 2025 (planned sample size: 20). To date, eight participants have enrolled and completed induction. Median age was 76 years (range 41-88); 50% were female and 25% were Black/African American. Participants lived a mean of 30 miles from the treating facility. Forty home instillations were delivered, and all participants completed all recommended induction doses (100% adherence). Median nurse time in the home was 40 minutes. Five episodes of hematuria were self-limited; one urinary tract infection resolved with antibiotics. Self-efficacy improved from a median of 3 pre-treatment to 7 post-treatment. The median COST-FACIT score was 30 (scale 1-44). Mean EORTC QLQ-C30 global health status was 71 (0-100). EORTC QLQ-NMIBC24 averages showed urinary symptoms rising during induction (23 at baseline to 30 at 6 weeks) with improvement by 12 weeks (18) and future worries decreasing (33 to 25); intravesical treatment issues remained low (5 to 2). Conclusions: BCG at Home is, to our knowledge, the first prospective trial to administer intravesical BCG in the home setting using a standardized pharmacy-to-home pathway. Early results support feasibility, complete adherence, and an acceptable short-term safety profile. Clinical trial information: 07048496 .

e13611 Background: Decentralized cancer care models may reduce treatment burden for patients with advanced prostate cancer (CaP), particularly those facing mobility, transportation, of scheduling challenges. However, prospective patient-reported experience and quality-of-life data comparing home- versus clinic-based oncology care remain limited. Mayo Clinic Cancer CARE Beyond Walls (CCBW) is a patient-centered program designed to deliver selected standard-of-care cancer therapies in the home with virtual clinical oversight. This observational study evaluated patient-reported experience, feasibility, safety, and quality of life among men with advanced or metastatic CaP receiving care at home. Methods: Men with advanced/metastatic CaP receiving active standard-of-care therapy including hormone-based treatments, oral anticancer therapies, anti-bone resorptive agents, or intravenous chemotherapy who were participating in a CCBW randomized trial were enrolled into a companion observational study. After confirmation of treatment tolerance in clinic, patients received home-based care for 24 weeks (Arm A) or in-clinic care for 8 weeks followed by home-based care for 16 weeks (Arm B). Patient-reported outcomes were collected at baseline and Weeks 8, 16, and 24, using CAHPS-based measures and CCBW-specific surveys assessing overall cancer care experience, patient preference for site of care, comfort with home infusions, functional/symptom assessment and quality of life. Descriptive analyses were performed. Results: Eighteen participants were analyzed (Arm A n = 10; Arm B n = 8). Participants were medically stable, and predominantly insured by Medicare. Survey completion was 100% at baseline and 83% at all follow-up time points. At Weeks 16 and 24 when all respondents had received home-based care, 100% and 92% reported being “quite a bit” or “very much” comfortable receiving treatment at home. Communication with at-home and remote nursing teams was rated highly, and most respondents reported transition, scheduling, and equipment use easy or very easy. At Weeks 16 and 24, 45% and 40% of respondents reported improved quality of life from receiving home-based care, with no reports of worsening. No emergency department visits, hospitalizations, or urgent care visits occurred in either arm. Conclusions: In this prospective, observational study, home-based oncology care delivered through CCBW was feasible, safe, and associated with high patient satisfaction among men with advanced CaP receiving diverse systemic therapies. These findings support further evaluation and expansion of decentralized care integrating home-based treatment with virtual clinical oversight.

e13121 Background: Triple-negative breast cancer (TNBC) lacks reliable prognostic biomarkers beyond standard clinical staging, limiting individualized risk stratification and treatment planning. The neutrophil-to-lymphocyte ratio (NLR), a readily available marker of systemic inflammation, has been proposed as a prognostic indicator in TNBC; however, existing evidence remains inconsistent. We performed an updated systematic review and meta-analysis to evaluate the prognostic value of pretreatment NLR in the contemporary treatment era. Methods: PubMed, Embase, Cochrane CENTRAL, and ClinicalTrials.gov were systematically searched from database inception through January 1, 2026, for randomized and observational studies reporting associations between pretreatment NLR and survival outcomes in TNBC. Two reviewers independently screened studies and extracted data with discrepancies resolved by consensus. Outcomes included overall survival (OS), disease-free survival (DFS), and progression-free survival (PFS). Hazard ratios (HRs) were pooled using random-effects models. Risk of bias was assessed using ROBINS-I tool. Prespecified subgroup and sensitivity analyses were performed based on NLR cut-off values, follow-up duration, geographic region, and risk of bias. Results: Twenty-three retrospective studies comprising 4,731 patients with TNBC were included. On multivariate analysis, elevated pretreatment NLR was independently associated with poorer OS (HR 2.21, 95% CI: 1.56–3.13) and DFS (HR 1.97, 95% CI: 1.65–2.37. Similar associations were observed on univariate analysis (OS: HR 1.70, 95% CI: 1.07–2.72; DFS: HR 1.84, 95% CI: 1.14–2.98). No statistically significant or consistent association was observed between NLR and PFS. Associations between high NLR and adverse OS and DFS remained robust across prespecified subgroup and sensitivity analyses, representing the largest contemporary synthesis of multivariable-adjusted outcomes in TNBC. Key pooled outcome associations are summarized in Table 1. Conclusions: Elevated pretreatment NLR is independently associated with worse OS and DFS in patients with TNBC, supporting its potential role as a low-cost tool for clinical risk stratification and treatment planning. Given its availability from routine blood tests, NLR may assist in identifying high-risk patients who could benefit from intensified surveillance or therapeutic strategies. Prospective validation in the modern chemo-immunotherapy era is warranted. Summary of pooled associations between pretreatment NLR and survival outcomes in TNBC. Outcome Studies (n) Interpretation Overall survival 14 Worse survival Disease-free survival 15 Worse survival Progression-free survival 3 Inconclusive

e13082 Background: Human epidermal growth factor receptor 2 (HER2)–low breast cancer, defined as HER2 immunohistochemistry (IHC) 1+ or IHC 2+/in situ hybridization–negative, represents a newly targetable subtype comprising nearly half of all breast cancers. Brain metastases are a common and morbid complication of metastatic breast cancer, yet patients with active central nervous system (CNS) disease are frequently excluded from clinical trials. Trastuzumab deruxtecan (T-DXd), an antibody–drug conjugate with a cleavable linker and potent topoisomerase I inhibitor payload, has demonstrated substantial intracranial activity in HER2-positive disease. However, the intracranial efficacy of T-DXd in patients with HER2-low breast cancer remains incompletely characterized. Methods: A systematic literature search was conducted across PubMed/MEDLINE, Embase, CENTRAL, ClinicalTrials.gov, and Web of Science from database inception through January 1, 2025. A total of 2,275 records were identified and screened. Eligible studies included randomized controlled trials and prospective or retrospective clinical studies evaluating trastuzumab deruxtecan in patients with HER2-low metastatic breast cancer and measurable brain metastases. Studies were required to report intracranial objective response rate (IC-ORR), defined as complete or partial intracranial response among CNS-evaluable patients, assessed by study-defined criteria (RECIST 1.1 or RANO-BM). Results: Five studies comprising 62 patients with HER2-low metastatic breast cancer and brain metastases were included. Using a random-effects proportional meta-analysis with Freeman–Tukey double arcsine transformation, the pooled intracranial objective response rate (IC-ORR) was 46% (95% CI, 27–65%). Between-study heterogeneity was moderate (I² = 47.7%, p = 0.11), with consistent directionality of intracranial activity observed across included cohorts. Conclusions: Across five studies, T-DXd demonstrated clinically meaningful intracranial activity in HER2-low metastatic breast cancer with brain metastases, yielding a pooled IC-ORR of 46%. This provides one of the first quantitative benchmarks of CNS response in HER2-low disease, where evidence has been limited to small, heterogeneous cohorts. These findings support dedicated prospective trials in HER2-low patients with active CNS disease and standardized intracranial endpoints to refine patient selection and expected benefit. Summary of outcomes. Study Year CNS-Evaluable Patients (N) Intracranial Responders (CR+PR) IC-ORR (%) Zhou et al. 2025 15 7 46.7 (21.0–73.0) Batista et al. 2024 6 3 50.0 (12.0–88.0) Lazaratos et al. 2024 6 4 66.7 (22.0–96.0) Duan et al. 2025 9 6 66.7 (30.0–93.0) Burnside et al. 2024 26 6 23.1 (9.0–44.0) Pooled estimate (random effects) — 62 26 46.0 (27.0–65.0)*

e13076 Background: Progression-free survival (PFS) is frequently used as a primary endpoint in contemporary oncology trials, including antibody–drug conjugate (ADC) studies in metastatic breast cancer (MBC) settings, despite uncertainty regarding its validity as a surrogate for overall survival (OS). A meta-epidemiological analysis was performed to quantify the systematic differences between the treatment effects on PFS and OS in ADC randomized clinical trials (RCTs). Methods: Phase II–III ADC RCTs with MBC patients reporting hazard ratios (HRs) with 95% confidence intervals (CIs) for both progression-free survival (PFS) and overall survival (OS) were included. Differences in treatment effects within each trial were quantified using the ratio of hazard ratios (rHR = HR_PFS/HR_OS). Random-effects models were used to pool the rHRs across the trials. Prespecified subgroup and meta-regression analyses were used to evaluate the trial characteristics, clinical context, and regulatory status. Sensitivity analyses assessed the robustness across varying assumptions of the within-trial correlation between the endpoints. Results: Twenty-one RCTs evaluating nine ADCs in patients with MBC were included, comprising three phase II (14%) and 18 phase III (86%) studies. The pooled rHR demonstrated significantly larger treatment effects for PFS than for OS (rHR, 0.79; 95% CI, 0.73–0.86), with no between-trial heterogeneity (I² = 0%, τ² = 0). Sensitivity analyses assuming within-trial correlations between PFS and OS ranging from 0 to 0.95 yielded consistent results. Greater divergence between endpoints was observed in trials enrolling patients with triple-negative breast cancer (rHR, 0.72; 95% CI, 0.61–0.85) and HER2-low disease (rHR, 0.77; 95% CI, 0.62–0.96). Phase III trials showed larger differences than phase II trials (rHR, 0.79 vs. 0.89). When OS was a secondary endpoint, divergence was greater than when OS was primary (rHR, 0.77 vs. 0.87). Across trials, 16 of 21 studies (76%) demonstrated concordant effect directions between PFS and OS: 11 (52%) with a statistically significant benefit for both endpoints and 5 (24%) with neither endpoint significant. Discordance occurred in five trials (24%), all characterized by a statistically significant PFS benefit without a corresponding OS improvement. No trial demonstrated an OS benefit in the absence of a PFS benefit. Conclusions: Across ADC trials, PFS systematically overestimated OS treatment effects, underscoring the limitations of PFS as a standalone surrogate endpoint. These findings support the cautious interpretation of PFS-driven efficacy and reinforce the need for endpoint validation frameworks tailored to the mechanism, disease context, and trial design.

e12749 Background: Breast cancer (BC) survivors are at higher risk for recurrence or new primary disease and often require complex surveillance imaging. Use of contrast enhanced surveillance imaging modalities with contrast-enhanced digital mammography (CEM) and magnetic resonance imaging (MRI) has increased in recent years. This study evaluates characteristics of those BC survivors who receive contrast enhanced imaging and whether the addition of contrast enhanced imaging affects biopsy outcomes in BC survivors. Methods: An IRB-approved retrospective chart review identified female BC survivors who underwent breast surgery and subsequent surveillance imaging at a single academic center between 2016 and 2025. Surveillance episodes were categorized as mammography alone versus mammography with addition of CEM and/or MRI. Multivariable generalized estimating equations were used to compare patient and tumor characteristics associated with enhanced imaging modality use. Similarly rates of biopsy and cancer were evaluated with enhanced imaging use. Results: A total of 4,050 surveillance imaging episodes in 861 patients were identified and 54 resulted in biopsy-proven malignancy. Mammography alone was performed in 3,459 episodes, while enhanced imaging with CEM or MRI was used in 591 (14.6%) episodes. Use of CEM or MRI for surveillance imaging increased over time. In 2016, surveillance imaging consisted predominantly of mammography alone (93.3%) with 6.6% incorporating MRI or CEM. By 2025, mammography only surveillance decreased to 78.4% while use of MRI or CEM increased to 21.6%. Use of contrast enhanced imaging was associated with higher incidence rate ratios (IRR) for dense breast tissue [IRR 2.33; 95% CI 1.92, 2.82), p < 0.001] and less frequently used among patients aged 65–79 years [IRR 0.60, 95% CI 0.49, 0.74; p < 0.0001] and > = 80 years of age [IRR 0.40; 95% CI 0.24, 0.66; p < 0.001]. Ductal carcinoma in situ (DCIS) (IRR 3.09, p = 0.0061), and immunotherapy use (IRR 2.56, p = 0.0006) also were associated with increased use of CEM/MRI enhanced imaging. Biopsies were performed in 146 (4.2%) mammography alone episodes and 55 (9.3%) enhanced imaging episodes [IRR 2.20; 95% CI 1.63, 2.96; p < 0.001]. Surveillance with mammography yielded malignant biopsy results in 39 (1.1%) episodes, compared with 15 (2.5%) episodes using enhanced imaging [IRR 2.25; 95% CI 1.25, 4.06; p = 0.007). Conclusions: In breast cancer surveillance at our institution, the addition of contrast enhanced imaging modalities were utilized in a minority of surveillance episodes but did increase over time and were higher in patients with dense breasts. CEM or MRI usage demonstrated higher biopsy rates and increased malignancy detection compared with mammography alone, but the incidence of a positive biopsy was low. These findings suggest and are in keeping with 2023 ACR guidelines that enhanced imaging may improve cancer detection in select breast cancer survivors.

e12707 Background: Anthracycline-based chemotherapy remains a cornerstone of breast cancer treatment but is limited by dose-dependent cardiotoxicity. Sodium-glucose cotransporter-2 inhibitors (SGLT2i) have demonstrated cardioprotective effects across diverse populations. Preclinical models suggest they may mitigate anthracycline-induced cardiotoxicity. However, clinical data evaluating this association remain limited. Methods: We conducted a retrospective cohort study using the TriNetX real world data platform, including adults with breast cancer who received anthracycline within one year of diagnosis. Patients were stratified by SGLT2i use within one year of diagnosis into the SGLT2i group and the non-SGLT2i group. Propensity score matching (PSM) was performed to balance baseline demographics and comorbidities. Outcomes included 3-year all-cause mortality, heart failure, myocardial infarction, atrial fibrillation, mean left ventricular ejection fraction (LVEF), mean Troponin I, and mean brain natriuretic peptide level (BNP), analyzed using risk ratios (RR) and Kaplan-Meier survival analysis. Results: After PSM, 2912 patients were included in each group, with a mean follow-up of 630.3 days in SGLT2i group and 756.7 days in non-SGLT2i group. Mean age was 61.5 years vs 62.3 years (SGLT2i group vs non-SGLT2i group), with more than 98% of females in both groups. Most patients were White (49.0% in SGLT2i group and 48.6% in non-SGLT2i group), followed by African American (23.7% vs. 23.4%), unknown races (14.0% vs 14.0%), and Asian (9.5% vs. 9.8%). At baseline, the SGLT2i group had lower mean LVEF (53.4% vs 61.9%), higher mean Troponin I (0.992 vs 0.0849), and higher mean BNP levels (778 vs 240). SGLT2i group was associated with significantly lower 3-year all-cause mortality (Hazard ratio 0.52, 95% CI 0.44–0.61). Heart failure incidence (9.5% vs 6.0%; p = 0.0005) was significantly higher in the SGLT2i group. Mean LVEF in SGLT2i group was significantly lower (51.7% vs 58.9; p < 0.0001) and mean BNP level was significantly higher in SGLT2i group (685.5 vs 383.0; p = 0.0336). No significant differences were observed in myocardial infarction (3.9% vs 3.4%; p = 0.4459), atrial fibrillation (3.4% vs 4.5%; p = 0.0799), and mean troponin I (0.085 vs 0.113, p = 0.5191). Conclusions: In this real-world cohort, SGLT2i use was associated with lower 3-year all-cause mortality despite higher rates of heart failure. Notably, patients receiving SGLT2i had worse baseline cardiac function yet demonstrated more favorable trends in cardiac biomarkers, including smaller declines in LVEF, reductions in BNP, and lower mean troponin I levels, suggesting a slower progression of cardiac dysfunction. These findings support a potential cardioprotective and survival benefit of SGLT2i in patients with breast cancer receiving anthracycline therapy and warrant confirmation in future studies.

e12697 Background: Postpartum-associated breast cancer (PABC) has been defined clinically as breast cancer (BC) diagnosed within the first 5 years of the most recent birth. Though generally rare, incidence rates are increasing in conjunction with delayed childbearing and older maternal age at first birth. Currently, there are limited data regarding serial patient-reported outcomes in this patient population compared to non-PABC patients. Methods: Patients with PABC from the Mayo Clinic Breast Disease Registry who completed baseline, 2, and 4-year surveys were matched 1:1 to BC patients whose cancers occurred more than 5 years after their most recent birth (or in the setting of nulliparity) based on age, clinical stage, treatment received, and tumor subtype. Survey results from the Patient Health Questionnaire-2 (PHQ-2), Patient-Reported Outcomes Measurement Information System-10 (PROMIS-10), and Impact of Event Scale-Revised (IES-R) collected at approximately two and four years after diagnosis were compared between PABC and non-PABC patients. Univariable analyses used Wilcoxon rank sum tests, whereas multivariable analyses employed linear regression models adjusting for potential confounding effects. Results: A total of 222 individuals were included (111 with PABC). A higher proportion of individuals in the PABC cohort were married compared to the non-PABC cohort (80% vs. 42%, p < 0.001); otherwise, the groups were well-balanced across multiple categories, including age, gender, race/ethnicity, menopausal status, and germline mutation status. In univariable analyses, the Year 2 composite PHQ-2 score was significantly worse among individuals with non-PABC (p = 0.04), and the non-PABC cohort reported greater difficulty with sleep (p = 0.03) as measured by IES-R at Year 4. Both associations attenuated in a multivariable analysis controlling for marital status. In marital status-adjusted analyses of Year 4 survey results, PABC participants reported greater difficulty in carrying out social activities but were less likely to report emotional distress as evaluated by PROMIS-10 (compared with non-PABC participants). No other variables were significant univariably or multivariably (p > 0.05). Conclusions: In general, quality of life is similar among survivors of PABC compared to those diagnosed with breast cancer outside the postpartum period (or when nulliparous). However, our findings reveal that individuals with PABC are less likely to experience emotional distress 2 and 4 years after the BC diagnosis, which is unexpected, given that postpartum patients typically report higher levels of distress compared to their non-postpartum counterparts. Further investigation into these findings is warranted.

e12691 Background: Breast cancer prognosis is influenced not only by tumor-specific factors but also by systemic inflammatory responses. Elevated circulating neutrophils after surgery may reflect one such systemic inflammatory response that promotes a pro-tumorigenic environment. Neutrophil extracellular traps (NETs) have been recognized as promoters of cancer activity. However, there have been no studies looking at neutrophil count alone as an independent inflammatory marker in cancer. Clinical prognostic significance of post-operative neutrophil counts remains incompletely understood. If proven significant, neutrophil count is a simple, widely available measure to predict post-operative outcomes in patients with breast cancer. Methods: Data from the Mayo Clinic Platform were retrospectively analyzed, including only breast cancer patients with normal BMI and neutrophil counts recorded within one week after breast surgery. Patients who underwent radical mastectomy were excluded. Patients were stratified into two groups based on neutrophil count: high (>7×10⁹/L) and normal (1.7–7×10⁹/L). Clinical outcomes assessed included age distribution and 5-year overall survival. Age differences were evaluated using Cohen’s D, and Kaplan-Meier survival curves and hazard ratio estimation were performed using the Mayo Clinic Platform's tool. Results: A total of 899 patients were included in the study cohort: 303 in the high neutrophil group (Cohort A) and 596 in the normal neutrophil group (Cohort B). Age distributions were comparable between groups (Cohort A mean 59.2 ± 13.1 years; Cohort B mean 59.1 ± 14.3 years; Cohen's d = 0.0079). High neutrophil counts were significantly associated with reduced 5-year survival (77.8% vs. 84.5%) and an increased risk of mortality (HR 1.63; 95% CI: 1.16–2.29; P = 0.0041). Conclusions: Recent literature supports that surgery-induced NET formation may drive metastatic progression. Findings from this retrospective analysis at Mayo Clinic suggest that elevated neutrophil counts after breast cancer surgery are associated with poorer survival and may reflect systemic inflammation. While markers like NLR and NPAR have prognostic value, neutrophil count alone is a practical, accessible biomarker for clinical use. Limitations of this study include potential confounding factors such as lifestyle and comorbidities, and lack of subgroup analysis by breast cancer type, stage, and other treatments in addition to surgery. Further prospective studies are still needed for validation. Five-year survival rate comparison. Statistic High Neutrophil counts Normal Neutrophil counts Patient Count 303 596 1 Month Survival 99% 99.8% 5 Month Survival 97% 99.3% 10 Month Survival 94.4% 97.3% 30 Month Survival 85.4% 91.9% 60 Month Survival 77.8% 84.5% Hazard Ratio* 1.63 (95% CI: 1.16–2.29) P = 0.0041.