Background: Tumour lysis syndrome (TLS) is an oncologic emergency classically associated with hematologic malignancies but increasingly recognised in solid tumours. Contemporary population-level data describing TLS among patients with gastrointestinal (GI) malignancies remain limited.
Methods: We performed a retrospective serial cross-sectional analysis of the National Inpatient Sample from 2017 to 2022. Adult hospitalisations with TLS were identified and classified according to the presence of oesophageal, gastric, small-intestinal, colorectal, liver/biliary or pancreatic malignancy. Survey-weighted analyses estimated national hospitalisation rates and temporal patterns. Multivariable models compared mortality, length of stay (LOS), total charges, clinical severity and disposition between TLS hospitalisations with and without GI malignancy and evaluated factors associated with mortality among GI-TLS hospitalisations.
Results: An estimated 90,680 adult TLS hospitalisations were identified, including 3,920 (4.3%) associated with GI malignancy. From 2017 to 2022, GI-TLS increased from 1.53 to 2.89 per 100,000 adult hospitalisations and from 8.72 to 14.37 per 10,000 GI-cancer hospitalisations; however, the linear temporal trend did not reach conventional statistical significance (OR per year, 1.04; 95% confidence intervals (CI), 1.00–1.09; p = 0.051). GI-TLS was associated with higher in-hospital mortality than TLS without GI malignancy (34.6% versus 23.9%; adjusted OR, 1.42; 95% CI, 1.21–1.67; p < .001), despite shorter LOS (adjusted difference, −4.62 days) and lower total charges (−$86,864; both p < 0.001). Among GI-TLS hospitalisations, metastatic malignancy was independently associated with mortality. After incorporation of acute severity measures, metastatic disease, sepsis, mechanical ventilation and renal replacement therapy remained associated with death, whereas age, sex, race/ethnicity and GI cancer site were not.
Conclusion: GI-associated TLS is uncommon but carries substantial excess inpatient mortality. Its national hospitalisation burden increased numerically over time, while mortality was more strongly associated with metastatic disease and acute physiologic deterioration than with age or anatomic cancer site.