Abstract Introduction: Endometrial cancer incidence has increased substantially in the past two decades, with the increases occurring primarily in tumors of non-endometrioid histology, which have a poor prognosis. Evidence regarding the origin(s) of the increase is sparse. We sought to determine whether women who had particular molecular signatures of endogenous and exogenous exposures had an increased risk of non-endometrioid histology, particularly serous tumors. Methods: We investigated single-base substitution (SBS) signatures in exome sequencing data from The Cancer Genome Atlas (TCGA). Standard algorithms for mutational signature assessment were applied. Signatures were evaluated on a continuous scale, and also using a high/low cut point determined by maximally selected rank statistics. Relative risks (RR) and 95% confidence intervals (CI) were computed for 49 signatures, comparing risk for serous in relation to endometrioid histology. Disease-specific survival (DSS) was also evaluated in Cox proportional hazard models, with calculation of hazard ratios (HR) and 95% CI. The proportional hazards assumption was verified by Schoenfeld residuals. All analyses were adjusted for age at cancer diagnosis, and DSS analyses were also adjusted for stage. Results: Included were n=414 women with endometrioid and n= 134 with serous non-endometrioid tumors. High Mismatch Repair defective (dMMR) (SBS6 and SBS15) and Polymerase Epsilon mutation (POLE) (SBS10a; SBS10b) signatures were less common in serous than endometrioid tumors, as expected from the literature (dMMR: SBS6 RR 0.21;95% CI 0.12-0.39; SBS15 0.22;95% CI 0.12-0.40;SBS26 0.21;95% CI 0.12-0.40); SBS15 RR 0.22;95% CI 0.12-0.40 and POLE SBS10a RR 0.23;95% CI 0.10-0.54 and SBS10b 0.33; 95% CI 0.19-0.58). A signature related to tobacco use (SBS4) was also less common in serous tumors (RR 0.32;95% CI 0.15-0.71). Women with high dMMR (SBS6: HR 0.06;95%CI 0.01-0.47; SBS15 HR 0.23;95%CI 0.08-0.64; SBS26: HR 0.42;95% CI 0.21-0.84)) or high POLE (SBS10a HR 0.06;95% CI 0.01-0.46; SBS10b HR 0.13; 0.03-0.54) signatures had a reduced risk of endometrial cancer-specific mortality. Discussion: Endometrioid and serous tumors differ in mutational signatures. The reduced dMMR and POLE signature risk in relation to both serous tumors and DSS are in agreement with other findings. Our results open up new prospects for exploration of serous tumor etiology Citation Format: Deirdre A. Hill, Carolyn Y. Muller, Kimberly K. Leslie, David G. Mutch. Assessing endometrial cancer etiology by histologic subgroups [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2026; Part 1 (Regular Abstracts); 2026 Apr 17-22; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2026;86(7 Suppl):Abstract nr 2320.

BACKGROUND:Cytomegalovirus (CMV) infection poses a significant risk to kidney transplant recipients. This study investigated CMV disease incidence, outcomes, and management challenges in racial and ethnic minority populations following kidney transplantation. METHODS:This single-center, mixed-methods study included a retrospective cohort analysis of kidney transplant recipients (n = 58) and qualitative surveys of healthcare providers. Patients were categorized as minorities (n = 49) or non-Hispanic whites (n = 9). The primary outcome was CMV disease incidence. Secondary outcomes included graft failure, mortality, and identification of management barriers. RESULTS:The cumulative incidence of CMV disease was higher in minorities than in non-Hispanic whites (12.3% vs. 0%, p = 0.58), although the difference was not statistically significant. All graft failures (8.6%, n = 5) occurred in the minority group. Although not statistically significant, all-cause mortality was higher in the minority group (24.5% vs. 11.1%, p = 0.54), with 46.2% of the deaths occurring within 90 days of CMV diagnosis. Qualitative analysis revealed challenges in diagnosis, treatment-related side effects, medication costs, and insurance barriers. The providers emphasized the importance of interdisciplinary collaboration and standardized protocols. CONCLUSION:While limited by the small sample size, this study highlights potential disparities in the incidence and outcomes of CMV disease among minority kidney transplant recipients, suggesting that barriers in care and access may contribute to these differences. These hypothesis-generating findings underscore the need for larger multicenter studies to validate these patterns and to inform targeted strategies that may reduce inequities in post-transplant outcomes.

Abstract Background Disparities in kidney transplant evaluation for minorities raise concerns about post-transplant care access, including cytomegalovirus (CMV) infections and their impact. While CMV significantly affects morbidity and mortality rates, the precise ramifications of these disparities remain unclear. We aimed to evaluate CMV infection patterns in minority kidney transplant recipients. Methods We evaluated CMV infection in minority kidney transplant recipients using retrospective analysis and qualitative surveys. Patients aged ≥ 18 years with post-transplant CMV infection were included. Data were collected from University of New Mexico Health Sciences Center records and provider surveys. The primary outcome was CMV disease incidence among minority populations, with secondary outcomes exploring clinical endpoints and barriers to CMV management. Quantitative and qualitative data were analyzed using descriptive statistics, chi-square and Fisher’s exact tests, and thematic analysis. Results Among 58 patients (84.5% minorities), CMV disease cumulative incidence was 12.3% in minorities vs. 0% in non-Hispanic whites (p = 0.58), despite similar prophylaxis. No significant CMV disease risk factors were found. Graft failure occurred in 8.6% of patients, mostly minorities, with one graft loss after CMV diagnosis. Mortality appeared higher in minorities (24.4% vs 11.1%, p = 0.67), especially within 90 days of CMV diagnosis, and notably elevated in diabetics (40% vs 9.1%, p = 0.01). Eight respondents (75% transplant specialists) highlighted CMV management challenges from diagnosis to resource access. Providers acknowledged limitations in current strategies and expressed optimism for newer therapies, such as letermovir. Systematic barriers, including policy gaps and suboptimal multidisciplinary collaboration, were identified as hindrances to comprehensive care delivery. Conclusion Our study underscores the CMV disease burden among minority kidney transplant recipients, highlighting disparities in incidence and clinical outcomes compared to non-Hispanic whites. Urgent interventions and policy reforms are required to address systemic barriers and improve post-transplant care equity, ultimately enhancing the health outcomes of minority transplant patients. Disclosures M. Gabriela Cabanilla, PharmD, PhC, Merck & Co: Grant/Research Support

SEER age-adjusted breast cancer incidence rates for six counties of New Mexico, by ethnicity and age.

OBJECTIVES There is little data evaluating procedural skills in current rural pediatric practices. In order to prepare a cadre of pediatricians to work in rural settings, we require an understanding of the unique procedural skills needed by rural pediatric providers. Our objective was to determine how often pediatricians performed various procedural skills, determine the importance of these skills to current practice, and how they differ between rural and urban pediatric providers. METHODS A survey evaluating pediatrician utilization of the 13 required Accreditation Council Graduate Medical Education procedural skills in current practice was developed and distributed to pediatric providers in New Mexico. Descriptive statistics were used to profile participants and describe survey responses. Chi-square tests were used to evaluate differences by urban setting or IHS. Fisher’s exact test was employed to assess differences if cell sizes were less than five. All p-values were two sided with alpha=.05. Benjamini-Hochberg method was used to control for type 1 errors. RESULTS Fifty-two of 216 pediatric providers responded. The majority surveyed performed each of the 13 procedures less than monthly but competency in many of these procedures is important. Thirty-two respondents submitted free-text responses recommending competence with tracheostomy changes, gastrostomy-tube changes/cares, and circumcision. CONCLUSION Majority of surveyed pediatricians performed the required procedures less than monthly but deemed several procedures to be important. Rural pediatricians recommended specific procedural skills needed in rural practice. All trainees receive procedural skills training. However, trainees interested in rural practice may need additional training in specific skills different than their non-rural counterparts.

Social media is increasingly used by patients for the management of skin conditions like acne, despite the potential risk for low-quality information. This study surveyed 45 participants between the ages of 12 and 17 years to investigate factors that could be associated with social media use among adolescents with acne. The likelihood of social media use was not significantly increased by clinical severity of acne, more severe physical barriers (greater than or equal to 20 miles to the dermatology clinic), more severe temporal barriers (waiting 12 or more weeks for a first dermatology appointment), or worsened quality of life (assessed via the Skindex-Teen score). This study increases understanding of adolescents' social media behaviors, particularly as a way to seek information for skin conditions like acne.

INTRODUCTION:Although Hispanic White (HW) females have a lower incidence of breast cancer than non-Hispanic White (NHW) females, breast cancer risk is unclear for HW females after benign breast disease (BBD). METHODS:We compared BBD characteristics and subsequent breast cancer risk among HW and NHW females in New Mexico using a population-based collection of benign breast biopsies (1996-2007). BBD was categorized as nonproliferative disease (NPD), proliferative disease without atypia (PDWA), or atypical hyperplasia (AH). Breast cancer risk was assessed as absolute risk (AR) using cumulative incidence and RR by comparing the number of breast cancer events in BBDs to non-BBD. RESULTS:This study included 3,684 HW and 6,587 NHW females with BBD. HW females had similar proportions of NPD (58.6% vs. 54.3%), PDWA (21.4% vs. 23.5%), and AH (3.6% vs. 3.3%) as NHW females. Breast cancer risk among all females with BBD was higher than population-based expected rates (RR, 1.87) and was similar for HW and NHW subgroups (RR = 1.99 vs. 1.84). As expected, breast cancer risk increased with increasing BBD severity, both overall [RR, 1.81 (NPD), 1.85 (PDWA), and 3.10 (AH)] and in the HW and NHW subgroups. Adjusted AR of breast cancer at 5 years also increased with the severity of BBD (HW vs. NHW; NPD: 1.4% vs. 2.1%; PDWA: 1.5% vs. 2.7%; AH: 6% vs. 4.8%). CONCLUSIONS:We found similar breast cancer RRs and ARs in HW and NHW. Risk counseling should ensure that HW females receive breast cancer clinical management warranted by their similar absolute risks. IMPACT:The present population-based provides evidence for the clinical management of HW females with BBD for the prevention of breast cancer.

Breast cancer cumulative risk in females with atypical hyperplasia adjusted for age and calendar year.

Studies on benign breast disease in different races / ethnicities.

Background Osteomyelitis in children may produce severe sequelae. However, the frequency and distribution of such complications by type of osteomyelitis (chronic or acute) is not well described. Methods We searched the HealthFacts® database (containing medical information on 68 million individual patients in the United States) with 238 International Classification of Diseases (ICD) version 10 codes for acute osteomyelitis and chronic osteomyelitis appearing in 2015. Outcomes were recorded for each subject, including development of limb length discrepancies, pathologic fractures, mortality, and need for multiple surgeries or prolonged orthopedic care (one to two years following diagnosis). Gender, age and season of diagnosis were also assessed. Chi-square tests were used to compare differences between categorical variables, and t-tests between continuous variables. Results Eight hundred sixty-nine subjects were included (57.4% male). Children with chronic osteomyelitis were older than those with acute osteomyelitis (median 9.5 years vs 12.0, respectively, p = .0004). Diagnoses were more common in winter ( p = .0003). Four subjects died while hospitalized during the study period (two with acute osteomyelitis, two with chronic osteomyelitis). Limb length discrepancies were rare and similarly distributed between infection types (≤ 1.3% of subjects, p = .83). Subjects with chronic osteomyeltis were more likely to require long-term orthopedic follow-up (14.0% vs. 4.8% for acute osteomyelitis, p < .0001), suffer from pathologic fractures (1.5% vs < 1.0%, p = .003) and to require multiple surgeries (46.0% vs. 29.3%, p = .04). Conclusions Though infrequent, serious outcomes from osteomyelitis are more common with chronic osteomyelitis than acute osteomyelitis.

Introduction: Benign breast disease (BBD) is an important breast cancer (BC) risk factor, which may be classified as non-proliferative disease (NPD), proliferative disease without atypia (PDWA), or atypical hyperplasia (AH) for risk stratification. Data related to the frequency of specific types of BBD and their relationship to BC risk in the Hispanic American population are limited. To address this knowledge gap, we compared BBD and associated BC risk among Hispanic white (HW) and non-Hispanic white (NHW) in New Mexico (NM). Methodology: A retrospective IRB-approved study was performed of women 19 years or older residing in six counties in NM (Bernalillo, Sandoval, Sante Fe, Socorro, Torrance, Cibola/Valencia) between 1996 and mid-2007 to compare the frequency of BBD subtypes and BC risk among HW and NHW. We excluded women who had a history of BC prior to BBD diagnosis or who were diagnosed with BC within 6 months after BBD biopsy. Race and ethnicity were self-reported by women at the time of biopsy. BBD was categorized as NPD, PDWA, or AH based on medical records. Incident BC (in-situ or invasive) was ascertained via linkage to the NM Surveillance Epidemiology End Results (SEER) Registry and BC risk was assessed using standardized incidence ratios (SIRs), comparing the observed number of BC events to that expected based on the NM SEER six-county race- and ethnicity-specific incidence rates, accounting for age and calendar period. Results: Our analysis included 3,870 HW and 6,996 NHW women with BBD. The HW were younger (47.1 vs. 51 years) compared to NHW. HW women had slightly more NPD (69.4% vs. 66.6%) but less PDWA (26.2% vs. 29.4%) and similar frequency of AH (4.3% vs. 3.9%) as compared to NHW. Over a median post-BBD follow-up period of 13 years (range 6 months-17 years), 644 BCs were observed (4.81% in HW and 6.55% in NHW). The observed BC risk among women with BBD was higher than population-based expected rates (SIR 1.98, 95% CI 1.82-2.13, p<0.001) and showed expected increases in risk with increasing degrees of BBD abnormality: SIR=1.90 for NPD, 2.00 for PDWA, and 3.01 for AH. Comparing BC risk by ethnic subgroups, HW women had an overall risk of BC after BBD that was statistically indistinguishable from NHW women (SIR=2.17, 95% CI 1.86-2.48 in HW women, and SIR=1.91, 95% CI 1.73-2.08 in NHW women). Within the major subgroups of the BBD findings, there were no significant differences in risk of BC after BBD for HW versus NHW women. Conclusions: In this population-based study, benign breast disease subtypes and their associated breast cancer risk were similar among the Hispanic and non-Hispanic white women. Citation Format: Kush Raj Lohani, Andrea M. Nibbe, Robert A. Vierkant, Laura M. Pacheco-Spann, Lisa R. Seymour, Celine M. Vachon, Mark E. Sherman, Amy C. Degnim, Deirdre Hill. Comparison of benign breast disease subtypes and breast cancer risk among Hispanic and non-Hispanic white women in New Mexico. [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 4213.

Objectives Dog bites occur frequently in the United States, yet there are no clear guidelines for prescribing antibiotic prophylaxis in healthy children after a dog bite. The aim of our study was to assess antibiotic prophylaxis and subsequent rates of infection after dog bites in children. We hypothesized a negative association between prophylactic prescription of any antimicrobial and return visit within 14 days for infection. Methods In this retrospective cohort study, we assessed the frequency of antibiotic prophylaxis prescribed after dog bite injuries in patients 0 to 18 years old and subsequent return visits for infection using 2016 to 2017 medical and pharmacy claims derived from the IBM MarketScan Research Databases. We used the International Classification of Diseases-10 code W54 for dog bites then used keyword searches to find diagnoses (including infection), wound descriptions, and medications. Results Over the 2-year period, 22,911 patients were seen for dog bites that were not coded as infected. The majority, 13,043 (56.9%), were prescribed an antibiotic at the initial visit and 9868 (43.1%) were not. Of those prescribed antibiotics, 98 (0.75%; 95% confidence interval [CI], 0.60–0.90) returned with an infection, compared with 59 (0.60%; 95% CI, 0.44–0.75) of those not prescribed antibiotics. Receiving an antibiotic prescription at the initial visit was associated with a reduced rate of return for wound infection only among children whose wounds were repaired or closed. Children not receiving a prescription whose wounds were repaired were more than twice as likely to return with an infection in the subsequent 14 days as children whose wounds were not repaired (odds ratio, 2.2; 95% CI, 1.2–4.0). Conclusions Most children are prescribed antibiotics at an initial emergency department visit after a dog bite. However, very few return for infection independent of antimicrobial prophylaxis, which suggests antibiotics are overprescribed in this setting.

Background Pediatric osteoarticular infections are commonly caused by Staphylococcus aureus. The contribution of S. aureus genomic variability to pathogenesis of these infections is poorly described. Methods We prospectively enrolled 47 children over 3 1/2 years from whom S. aureus was isolated on culture—12 uninfected with skin colonization, 16 with skin abscesses, 19 with osteoarticular infections (four with septic arthritis, three with acute osteomyelitis, six with acute osteomyelitis and septic arthritis and six with chronic osteomyelitis). Isolates underwent whole genome sequencing, with assessment for 254 virulence genes and any mutations as well as creation of a phylogenetic tree. Finally, isolates were compared for their ability to form static biofilms and compared to the genetic analysis. Results No sequence types predominated amongst osteoarticular infections. Only genes involved in evasion of host immune defenses were more frequently carried by isolates from osteoarticular infections than from skin colonization (p = .02). Virulence gene mutations were only noted in 14 genes (three regulating biofilm formation) when comparing isolates from subjects with osteoarticular infections and those with skin colonization. Biofilm results demonstrated large heterogeneity in the isolates’ capacity to form static biofilms, with healthy control isolates producing more robust biofilm formation. Conclusions S. aureus causing osteoarticular infections are genetically heterogeneous, and more frequently harbor genes involved in immune evasion than less invasive isolates. However, virulence gene carriage overall is similar with infrequent mutations, suggesting that pathogenesis of S. aureus osteoarticular infections may be primarily regulated at transcriptional and/or translational levels.

Abstract Background: Black, Hispanic, and Asian/Pacific Islander (API) women are disproportionately affected by less-common, more aggressive subtypes of breast cancer, and differences in reproductive factors may contribute to these disparities. We conducted a population-based case-case analysis comparing the risks of luminal B, triple-negative (TN), and HER2-overexpressing (H2E) breast cancer to the risk of luminal A breast cancer to better understand how reproductive risk factors influence the excess burden of aggressive breast cancer subtypes among racial/ethnic minority women. Methods: This case-case analysis was based on incident breast cancer cases, 20-69 years of age, diagnosed among residents within the respective catchment areas of two population-based cancer registries. Subtypes were defined by joint estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor receptor 2 (HER2) status: luminal A (ER+/HER2−), luminal B (ER+/HER2+), H2E (ER−/HER2+), and TN (ER−/PR−/HER2−). Data were collected through medical record reviews and structured interviewer-administered questionnaires. Categorical exposure variables included: parity, number of full-term pregnancies, history of breastfeeding, age at menopause, and age at menarche. Multinomial logistic regression models were fit to calculate odds ratios (OR) and associated 95% confidence intervals (95%CI) for each subtype relative to luminal A breast cancer, separately for non-Hispanic white, Hispanic white, Black, and Asian/Pacific Islander (API) women, and adjusting for age at diagnosis, study site, and year at diagnosis. Results: This sample included 4,557 women with breast cancer (2,047 luminal A, 335 luminal B, 1,559 TN, and 615 H2E). Among non-Hispanic white women, parity was more strongly associated with H2E than luminal A breast cancer (OR:1.24, 95%CI:0.99-1.53). Among Black and API women, parity was associated with a greater risk of TN (Black OR:1.41, 95%CI:0.72-2.78; API OR:2.43, 95%CI:1.12-5.29) and a greater risk of H2E (Black OR:2.14, 95%CI:1.78-2.57; API OR:3.73, 95%CI:2.18-6.37), relative to luminal A breast cancer. Breastfeeding was more strongly associated with the risk of luminal B than luminal A breast cancer among API women (OR:1.33, 95%CI:1.13-1.57). Older age at menarche was associated with an increased risk of TN breast cancer only among Black women. Conclusion: In this population-based study, the associations between some reproductive factors and less-common subtypes of breast cancer differed by race/ethnicity. The reproductive choices of women from different racial/ethnic groups are driven by a complex set of factors that seem to influence their subsequent risk of TN and H2E breast cancer. Future studies are needed to further clarify these mechanisms among Black and API women and to identify optimal points of intervention. Citation Format: Nicole C. Lorona, Linda S. Cook, Mei-Tzu C. Tang, Deirdre A. Hill, Charles L. Wiggins, Christopher I. Li. Relationship between reproductive factors and risk of luminal, triple-negative, and HER2-overexpressing breast cancer by race/ethnicity [abstract]. In: Proceedings of the AACR Virtual Conference: 14th AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2021 Oct 6-8. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2022;31(1 Suppl):Abstract nr PO-185.

Topical povidone-iodine, chlorhexidine, bacitracin, and vancomycin are commonly used antiseptic and antimicrobial agents to reduce risk and treat surgical site infections in numerous orthopedic procedures. Chondrocytes potentially may be exposed to these agents during operative procedures. The impact of these topical agents on chondrocyte viability is unclear. The goal of this study is to determine human chondrocyte viability ex vivo after exposure to commonly used concentrations of these topical antiseptic and antimicrobial agents. Human osteochondral plugs were harvested from the knee joint of a human decedent within 36 hours of death. Individual human osteochondral plugs were exposed to normal saline as a control; a range of concentrations of povidone-iodine (0.25%, 0.5%, and 1%), chlorhexidine (0.01% and 0.5%), and bacitracin (10,000 units/L, 50,000 units/L, and 100,000 units/L) for 1-minute lavage; or a 48-hour soak in vancomycin (0.16 mg/mL, 0.4 mg/mL, and 1.0 mg/mL) with nutrient media. Chondrocyte viability was evaluated with a live/dead viability assay at 0, 2, 4, and 6 days after exposure to bacitracin at 0, 3, and 6 days). Control subjects showed greater than 70% viability at all time points. Povidone-iodine, 0.5% chlorhexidine, and vancomycin showed significant cytotoxicity, with viability dropping to less than 40% by day 6. Chondrocytes exposed to 0.01% chlorhexidine maintained viability. Chondrocytes exposed to bacitracin showed viability until day 3, when there was a large drop in viability. Commonly used topical concentrations of povidone-iodine, vancomycin, and bacitracin are toxic to human chondrocytes ex vivo. A low concentration of chlorhexidine appears safe. Caution should be used when articular cartilage may be exposed to these agents during surgery. [Orthopedics. 2022;45(5):e263-e268.].

Antihypertensives are commonly prescribed medications and their effect on breast cancer recurrence and mortality is not clear, particularly among specific molecular subtypes of breast cancer: luminal, triple-negative (TN), and HER2-overexpressing (H2E). A population-based prospective cohort study of women aged 20–69 diagnosed with a first primary invasive breast cancer between 2004 and 2015 was conducted in the Seattle, Washington and Albuquerque, New Mexico greater metropolitan areas. Multivariable-adjusted Cox proportional hazards regression was used to estimate hazard ratios (HR) and 95% confidence intervals (CI) for risks of breast cancer recurrence, breast cancer-specific mortality, and all-cause mortality associated with hypertension and antihypertensives. In this sample of 2,383 luminal, 1,559 TN, and 615 H2E breast cancer patients, overall median age was 52 (interquartile range, 44–60). Hypertension and current use of antihypertensives were associated with increased risks of all-cause mortality in each subtype. Current use of angiotensin-converting enzyme inhibitors was associated with increased risks of both recurrence and breast cancer-specific mortality among luminal patients (HR: 2.5; 95% CI: 1.5, 4.3 and HR: 1.9; 95% CI: 1.2, 3.0, respectively). Among H2E patients, current use of calcium channel blockers was associated with an increased risk of breast cancer-specific mortality (HR: 1.8; 95% CI: 0.6, 5.4). Our findings suggest that some antihypertensive medications may be associated with adverse breast cancer outcomes among women with certain molecular subtypes. Additional studies are needed to confirm these findings.

Abstract Background: Presence of chronic kidney disease (CKD Stages 3-5) prior to breast cancer diagnosis may increase the risk of mortality among women with invasive breast cancer. However, the evidence base is limited, and the magnitude of this mortality risk is unknown. Breast cancer therapy may also be altered by presence of CKD. We sought to understand the role of CKD in breast cancer survival, with particular attention to receipt of recommended treatment. Methods: All women diagnosed with invasive breast cancer from 1992-2016 in 18 SEER-Medicare sites (age 66 or older; n= 168701) were evaluated for breast cancer-specific mortality (BCSM) using multivariate Cox models, with estimation of hazard ratios (HR) and 95% confidence intervals (CI). All analyses were adjusted for age, race/ethnicity, diagnosis year, tumor characteristics, and socioeconomic factors, and also for diabetes, myocardial infarction, and congestive heart failure prior to diagnosis. Separate analyses were run according to receipt vs non-receipt of standard of care for breast cancer treatment (defined according to National Comprehensive Cancer Network (NCCN) guidelines. Results: Median follow-up was 63 months (26 months with CKD). Women with CKD were at increased risk of BCSM (CKD Stage 3: HR 1.2; 95% CI 1.0-1.5; CKD Stage 4 HR 1.7; 95% CI 1.3-2.2; CKD Stage 5/End Stage Renal Disease HR 1.5; 95% CI 1.1-2.1), compared to women without CKD. In analyses of any CKD, restricted to women who met NCCN guideline therapy recommendations, women had an elevated risk of BCSM regardless of whether they did (HR 1.6; 95% CI 1.1-2.1) or did not (HR 1.4; 95% CI 1.0-1.8) receive recommended chemotherapy, and whether they did (HR 1.6; 95% CI 1.1-2.3) or did not (HR 1.3; 95% CI 0.9-2.0) receive recommended radiotherapy. Discussion: Women with CKD have an increased risk of breast cancer mortality regardless of receipt of guideline-based treatment. CKD is underascertained in Medicare claims data, thus the reported results (likely underestimates) will be presented with sensitivity analyses. CKD may influence breast cancer outcomes due to associated systemic inflammation and comorbid conditions, as well as release of soluble mediators such as cytokines, chemokines, growth factors, and factors involved in remodeling of the extracellular matrix and epithelial-mesenchymal transition. As such factors involved in CKD progression also influence cancer, increased understanding may provide clues to ameliorate adverse outcomes in both disease entities. Citation Format: Deirdre A Hill, Christos Argyropoulos, Maria-Eleni Roumelioti, Mark Unruh. Chronic kidney disease in breast cancer treatment and survival [abstract]. In: Proceedings of the 2019 San Antonio Breast Cancer Symposium; 2019 Dec 10-14; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2020;80(4 Suppl):Abstract nr P5-07-14.

Prophylactic clipping can decrease delayed post-polypectomy bleeding (DPPB) in large polyps (20mm) resected with endoscopic mucosal resection (EMR). However, despite the absence of strong evidence demonstrating clinical benefit, endoscopists usually place clips after large polypectomies. For example, multiple studies have shown differing results of clipping versus no clipping to prevent DPPB. Moreover, previous meta-analyses have also generated conflicting conclusions regarding the clinical benefit of clipping to reduce DPPB. Incorporating recently published studies from 2019, we conducted a meta-analysis to assess the efficacy of prophylactic clipping for polyps to prevent DPPB. We searched PubMed and the Cochrane library for studies comparing the effect of prophylactic clipping on DPPB. DPPB was defined as bleeding that occurred twenty-four hours after the procedure. All polyp sizes, location within the colon and endoscopic resection modalities were included. Studies with partially clipped polyps were excluded. Meta-analysis using the DerSimonian and Laird random-effects model was performed to establish a summary relative risk (RR) with 95% confidence interval (CI). The I-squared measure was used to assess heterogeneity. Fifteen studies were included in the analysis, representing eleven randomized controlled trials and four retrospective studies. A total of 5717 patients underwent 9130 polypectomies. Of the fifteen studies, nine were performed in Asia, three in Europe and three in North America. Two studies were multi-centered. Most studies were published within the past four years and three within the past year. Four studies utilized endoscopic submucosal dissection, eight standard polypectomy and seven EMR. The mean polyp size was 24.29 mm. Approximately 53% of the polyps had a proximal location and 41.6% had sessile morphology. Prophylactic clipping had a lower average incidence of DPPB (3.25%) compared to no clipping (4.45%). When we conducted a meta-analysis, the pooled relative risk of prophylactic clipping for DPPB was 0.60 (95% CI, 0.41-0.88), which favored clipping relative to no clipping. Heterogeneity was low among the studies (I-squared = 20.3%, P = 0.228). Patients who received prophylactic clipping had a reduced risk of delayed post-polypectomy bleeding that does not appear to be restricted only to large polyps undergoing EMR. Subgroup analyses are in progress to identify whether this decreased risk can be applied in other contexts, such as polyp size and location, mode of polypectomy (standard polypectomy, EMR, endoscopic mucosal dissection), and country where polypectomy was performed.