Validating Khorana Risk Score in gastric cancer patients on immune checkpoint inhibitors and chemotherapy

INTRODUCTION: Patients with gastric cancer are at a high risk of venous thromboembolism (VTE), and immune checkpoint inhibitors (ICIs) may further increase this risk. While the Khorana Risk Score (KRS) has been validated primarily in chemotherapy-treated populations, its utility in ICI-treated patients remains unclear. METHODS: Using the TriNetX Global Collaborative Network, we analyzed data from 2782 patients with gastric cancer treated with ICIs. Patients were stratified into high-risk (KRS ≥3) and intermediate-risk (KRS = 2) groups based on pre-treatment laboratory values and BMI. Cox proportional-hazards analyses were performed to evaluate the association between KRS and outcomes, including VTE, all-cause mortality, and arterial thrombosis, over a one-year follow-up period. RESULTS: High-risk patients had a 26% higher risk of VTE (HR: 1.26, [95% CI: 1.06-1.50]) and a 43% higher risk of all-cause mortality (HR: 1.43, [95% CI: 1.27-1.62]) compared to intermediate-risk patients. The incidence of deep vein thrombosis (DVT) was also significantly higher in the high-risk group (HR: 1.27, [95% CI: 1.01-1.59]), but no significant differences were observed for pulmonary embolism (PE) or arterial thrombosis. CONCLUSION: These findings suggest the KRS may effectively stratify VTE risk and mortality in gastric cancer patients treated with ICIs.