Outcomes of endovascular embolization in cancer-associated gastrointestinal bleeding: A nationwide inpatient analysis.

Abstract

e16340 Background: Advances in endovascular techniques have improved the technical success of embolization for gastrointestinal bleeding (GIB). However, embolization carries a risk of ischemic complications, particularly in colonic territories. This study aimed to evaluate the utilization patterns and clinical outcomes of endovascular embolization in gastrointestinal cancer-associated GIB. Methods: We performed a retrospective analysis of adult hospitalizations with cancer-associated GIB using the National Inpatient Sample database from 2016 to 2022. Cancer types included stomach, duodenum, pancreas, gallbladder, small intestine, and colon. Variables included age, sex, hospital size, severity (significant bleeding, invasive ventilation, blood transfusion, sepsis, peptic ulcer disease), and do-not-resuscitate status. Patients who underwent embolization were matched to non-embolized patients using propensity score matching with a logistic regression model. The covariates were used for nearest-neighbor matching using a caliper width of 0.01, and balance was assessed using standardized mean differences and variance ratios. In the matched cohort, crude mortality was assessed using χ² and mortality risk using logistic regression. Results: A total of gastrointestinal bleeding admissions was N = 47,085 stomach; 6,210 duodenum; 55,435 pancreas; 7,180 gallbladder; 8,400 small intestine; 106,165 colon, with endovascular embolization performed in 1.5%, 3.6%, 3.3%, 2.2%, 3.2%, and < 1% of cases, respectively. Embolized patients were similar or younger than non-embolized patients (stomach: 65 vs 65; duodenum: 66 vs 69; pancreas: 67 vs 66; gallbladder: 63 vs 68; small intestine: 66 vs 67; colon: 70 vs 69 years). Crude mortality did not differ between embolized and non-embolized patients with stomach (9.9% vs 9.7%), duodenal (11.1% vs 7.7%), pancreatic (12% vs 13.6%), gallbladder (6.5% vs 13.7%), or small intestinal cancers (11.3% vs 7.9%) (all p > 0.05), while higher crude mortality was observed in embolized patients with colon cancer (12.7% vs 6.7%, p < 0.05). After adjustment, embolization was associated with lower in-hospital mortality only in pancreatic cancer (aOR 0.5, p < 0.05). No significant associations were observed for stomach (aOR 0.9), gallbladder (aOR 0.04), or colon cancers (aOR 1.4) (all p > 0.05). Adjusted models for duodenal and small intestinal cancers were unstable due to complete separation from severe illness markers. Conclusions: Endovascular embolization was associated with significantly lower mortality in pancreatic cancer, while no benefit was observed for stomach, gall bladder, or colon cancers. Prospective studies are needed to define the optimal timing and modality of intervention, and hospital-level factors influencing mortality in these patients.