Lees, Elizabeth

Background: Colorectal cancer (CRC) remains one of the common causes of cancer-related morbidity and mortality in the United States. Emerging increases in early-onset CRC and persistent disparities remain major public health concerns. Objective: To characterize long-term CRC incidence and mortality trends in the United States, with particular emphasis on identifying demographic groups experiencing rising or plateauing disease burden. Methods: We conducted a population-based ecological study using CRC incidence data from the United States Cancer Statistics database (1999–2022) and mortality data from CDC WONDER (1999–2023). Temporal trends were evaluated using Joinpoint regression to estimate annual percent change (APC) and average annual percent change (AAPC), stratified by age, sex, race/ethnicity, and urbanization level. Results: Overall CRC incidence and mortality declined during the study period (both AAPC approximately −2.08%). However, incidence increased significantly among adults younger than 55 years, particularly those aged 20–24 years. Mortality also increased among younger adults aged 25–44 years and remained elevated among individuals aged 45–54 years. Non-Hispanic Black individuals consistently experienced the highest incidence and mortality rates. Mortality declines plateaued in several older age groups after 2018–2020. Conclusions: Despite overall improvements in CRC burden, increasing incidence and mortality among younger adults and persistent disparities highlight the need for risk-stratified prevention, earlier detection strategies, and tailored therapeutic approaches.

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.

1110 Background: CDK4/6 inhibitors with endocrine therapy are widely used for HR+/HER2– metastatic breast cancer (BC). While studies have shown similar progression-free outcomes across agents, overall survival (OS) data are limited. Since OS is a definitive endpoint and BMI may influence outcomes, this study examines BMI-dependent OS differences among CDK4/6 inhibitors. Methods: A retrospective cohort study was conducted using the Mayo Clinic Platform full AMC1 dataset. Postmenopausal women with BC receiving palbociclib/ribociclib/abemaciclib plus aromatase inhibitor (AI) were included. Patients with prior use of fulvestrant, anthracyclines, radiation therapy, GnRH agonists, or history of MACE, heart failure, myocardial infarction, or stroke before BC diagnosis were excluded. Patients were stratified by BMI and CDK4/6 inhibitor. The primary outcome was 5-year OS. Results: Among 1,989 patients (palbociclib: 868; ribociclib: 465; abemaciclib: 656), palbociclib was associated with significantly worse OS compared to ribociclib in BMI <25 (HR 2.91; 95% CI: 1.76–4.79; P < 0.01) and BMI ≥30 (HR 1.91; 95% CI: 1.21–3.01; P < 0.01). Compared to abemaciclib, palbociclib showed worse OS: BMI <25 (HR 1.73; P < 0.01), BMI 25–30 (HR 1.56; P < 0.01), and BMI ≥30 (HR 1.82; P < 0.01). No significant OS differences were observed between ribociclib and abemaciclib. Palbociclib patients were older, particularly in BMI <25 (Cohen's D = 0.39 vs. ribociclib; 0.27 vs. abemaciclib) and BMI ≥30 (0.28 vs. ribociclib; 0.23 vs. abemaciclib). In the BMI 25–30 group, palbociclib group was also older than ribociclib group (Cohen's D = 0.26). Conclusions: In postmenopausal BC patients on AIs and CDK4/6 inhibitors, palbociclib was associated with worse OS in BMI < 25 and BMI ≥ 30 groups, while ribociclib and abemaciclib showed similar outcomes across BMI groups. Palbociclib patients were older than those on other drugs, which may partially confound results; however, in the BMI 25–30 group, despite similar age differences, no survival difference was observed between palbociclib and ribociclib, suggesting age alone may have limited impact. These findings indicate a potential interaction between BMI and drug choice, and highlight the need for prospective studies to confirm and adjust for these variables. Limitations include the observational design and inability to perform multivariable regression analyses to adjust for confounders. Overall survival comparisons by CDK4/6 inhibitor and BMI subgroup. Comparison BMI Group Hazard Ratio (95% CI) P-value Palbociclib vs Ribociclib <25 2.91 (1.76 – 4.79) < 0.01 25 – 30 1.34 (0.87 – 2.071) 0.17 ≥30 1.91 (1.21 – 3.01) < 0.01 Palbociclib vs Abemaciclib <25 1.73 (1.29 – 2.32) < 0.01 25 – 30 1.56 (1.09 – 2.23) < 0.01 ≥30 1.82 (1.15 – 2.88) < 0.01 Ribociclib vs Abemaciclib <25 1.27 (0.81 – 1.99) 0.29 25 – 30 0.87 (0.54 – 1.43) 0.59 ≥30 1.05 (0.63 – 1.75) 0.85

10585 Background: Prior studies suggest that thyroid cancer (TC) survivors may have an elevated risk of secondary malignancies. However, whether this risk differs by TC histology, specifically with breast cancer (BC), remains unclear. We aimed to investigate the association between TC subtype—papillary thyroid carcinoma (PTC) versus medullary thyroid carcinoma (MTC)—and subsequent BC risk, adjusting for demographic factors. Methods: We conducted a retrospective cohort study using the SEER (2000–2022), including adults with a primary, microscopically confirmed PTC or MTC. Subsequent BC occurrence was defined as a binary outcome (yes/no). Multivariable logistic regression was used to estimate adjusted odds ratios (aORs) for MTC versus PTC, controlling for age (<50 vs ≥50 years), sex, and race. Stratified analyses by age and race were also performed. Stata 15 was used for statistical analyses. Results: 14,840 patients (14,563 PTC, 277 MTC) were included. MTC patients were older (mean 59.08±12.66 vs 56.16±12.98 years, p<0.001) and had a higher proportion of males (44.4% vs 29.4%, p<0.001). The overall incidence of secondary BC was lower in MTC patients (7.6% vs 22.5%, p<0.001). In unadjusted logistic regression, MTC was associated with significantly lower BC risk (OR=0.28, 95% CI: 0.18–0.44, p<0.001). After adjustment, MTC remained significantly protective (aOR=0.34, 95% CI: 0.22–0.55, p<0.001). Stratified analyses demonstrated consistent findings across age groups (<50: aOR=0.10, 95% CI: 0.03–0.42; ≥50: aOR=0.34, 95% CI: 0.21–0.54), , as well as white and Hispanic patients. Conclusions: Survivors of MTC have a substantially lower risk of developing secondary BC compared to PTC survivors. This association persists after adjustment for age, sex, and race, and is consistent across age and most racial subgroups. However, different BC types were not assessed due to limited number of BC patients among MTC survivors, and the small MTC sample size and potential survival differences between groups may affect the results. These findings highlight a possible effect of TC subtype on BC risk, suggesting the potential influence of underlying biological or genetic mechanisms. Baseline demographic characteristics of patients with papillary and medullary thyroid carcinoma. Characteristic Papillary Thyroid Carcinoma (PTC) (N=14,563) Medullary Thyroid Carcinoma (MTC) (N=277) P-value Age at Diagnosis 0.0002* Mean ± SD, years 56.16 ± 12.98 59.08 ± 12.66 Median, years 57 61 Sex, n (%) <0.001† Female 10,288 (70.6) 154 (55.6) Male 4,275 (29.4) 123 (44.4) Race, n (%) 0.015† White 10,263 (70.5) 197 (71.1) Black 921 (6.3) 15 (5.4) American Indian 77 (0.5) 1 (0.4) Asian 1,379 (9.5) 13 (4.7) Hispanic 1,903 (13.1) 50 (18.1) SD: Standard Deviation. *P-value from two-sample t-test (equal variances assumed). †P-value from chi-square test for the overall distribution across categories.

851 Background: Diffuse idiopathic skeletal hyperostosis (DISH) has been associated with increased risk of vertebral fractures in elderly men with prostate cancer. However, its potential role in the development of malignancies is poorly defined. In particular, the relationship between DISH and gastrointestinal (GI) cancers—including esophageal, gastric, colorectal, liver, biliary system, and pancreatic cancers—has not been examined. This study aimed to explore the risk of GI cancers among patients with DISH compared to those without DISH. We also assessed survival and incidence of vertebral fractures in these groups. Methods: Using the Mayo Clinic Platform (Full AMC1 dataset), we identified patients with and without a documented history of DISH. Outcomes included (1) prevalence and risk of GI cancers, (2) survival among GI cancer patients, and (3) vertebral fracture incidence. Relative risks (RRs) and hazard ratios (HRs) were calculated using SPSS20.0 and platform-based statistical tools, respectively. Kaplan–Meier survival analyses were performed to evaluate cancer survival outcomes. Results: A total of 6,189,860 patients were included, of whom 2,802 (0.05%) had DISH and 6,187,058 (99.95%) did not. Patients with DISH had a significantly higher prevalence of GI cancers compared with those without (RR = 1.63, 95% CI: 1.377–1.930). Survival analysis suggested worse outcomes among GI cancer patients without DISH (HR = 1.72, 95% CI: 1.25–2.35). Vertebral fracture incidence appeared lower among DISH patients, although low event numbers limit the reliability of this observation. Conclusions: DISH is associated with increased risk of GI cancers, while GI cancer patients without DISH may experience poorer survival. The observed trend toward lower vertebral fracture incidence among DISH patients should be interpreted cautiously due to limited event numbers. These findings highlight the importance of integrating musculoskeletal and oncologic perspectives in patient management and warrant further mechanistic and interventional studies. Survival analysis. Statistic Without DISH With DISH Patient Count 214,180 109 1 Month Survival 95.3% 98.2% 5 Month Survival 82.2% 87.9% 10 Month Survival 72.4% 85.1% 30 Month Survival 54.3% 74.1% 60 Month Survival 44.9% 60.6% Log-Rank 11.90 P-Value 0.00056 Hazard Ratio 1.72 (95% CI: 1.25 - 2.35)

331 Background: The relationship between plant-based dietary patterns and upper gastrointestinal (GI) cancers remains unclear. The Healthful Plant-Based Diet Index (hPDI) is a tool that measures adherence to plant-based diet and generates “scores” for clinical comparison. We conducted a systematic review and meta-analysis to examine the association between hPDI and the risk of esophageal and gastric cancers. Methods: A PubMed search identified relevant studies reporting on the association between hPDI and upper GI cancers. Reference lists were manually searched for additional studies. Study selection followed PRISMA guidelines, and quality was assessed using the Newcastle–Ottawa Scale (NOS). Pooled risk estimates were calculated using inverse-variance fixed-effects models, with subgroup analyses by cancer type. Sensitivity analyses were conducted using leave-one-out approach and by switching between fixed- and random-effects models. Forest plots and funnel plots were generated with RevMan 5.4, while Begg’s and Egger’s tests for publication bias were performed using Stata 15. Results: A total of four studies were included, all with high NOS scores. Overall, higher hPDI scores were associated with a significantly lower risk of upper GI cancers (RR = 0.64, 95% CI: 0.56–0.75). In subgroup analyses, the inverse association was consistent for both esophageal cancer (RR = 0.66, 95% CI: 0.54–0.79) and gastric cancer (RR = 0.63, 95% CI: 0.50–0.79). Between-study heterogeneity was low (I² = 35%, P = 0.16). Publication bias assessment indicated no evidence of small-study effects, as Begg’s test was non-significant (P = 0.88) and Egger’s test showed no significant bias (P = 0.76). Sensitivity analyses confirmed the robustness of the findings, with consistent results after sequential exclusion of individual studies and when using random-effects models. Conclusions: Higher hPDI scores were associated with a significantly reduced risk of esophageal and gastric cancers, indicating that adherence to a healthy plant-based diet may reduce upper GI cancer risk. These findings highlight the potential role of dietary modification in upper GI cancer prevention.

Abstract Introduction Case reports and series are critical to guide initial decision-making in a pandemic, but may have lower rigor because of the need to publish them quickly. This meta-epidemiologic study compares the methodological quality of case series that described the acute coronavirus disease 2019 (COVID-19) pandemic in 2020 versus those that described long-haul cases. Methods We conducted a systematic review in multiple databases for long-haul case series and reports. We identified early cases of acute COVID-19 synthesized in published systematic reviews. We evaluated the methodological quality by pairs of independent reviewers using a tool dedicated for appraising case series. Results We included 239 original case series (81 published in the first year of the pandemic and 158 published later describing long-haul COVID). The methodological quality of both groups of case series was very good (80–100% of series satisfying quality items) except for two items, the selection approach of cases included in the series and ruling out other causes that can explain the main finding described in the series. The appraisal tool demonstrated high agreement and reliability between reviewers. Conclusion The methodological quality of modern case series is high, except for two quality items that represent an area for potential for improvement for authors of case series describing future pandemics.