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

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. 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. 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. These findings suggest the KRS may effectively stratify VTE risk and mortality in gastric cancer patients treated with ICIs. Patients with stomach (gastric) cancer are at increased risk of developing blood clots, known as venous thromboembolism (VTE), which can include deep vein thrombosis (DVT) and pulmonary embolism (PE). These blood clots can be dangerous and even life-threatening. A scoring tool called the Khorana Risk Score (KRS) is commonly used to estimate the risk of blood clots in cancer patients receiving chemotherapy. However, it is not yet clear how well this tool works for patients receiving immunotherapy, specifically drugs called immune checkpoint inhibitors (ICIs). In this study, we used a large international medical database to look at 2,782 patients with gastric cancer who were treated with ICIs. We grouped the patients based on their KRS and compared their risk of developing blood clots and their overall survival. We found that patients with a higher KRS had a significantly greater risk of developing DVT and of dying within one year compared to those with a lower score. Our findings suggest that the Khorana Risk Score may help identify patients who are at greater risk for blood clots and death, even when they are being treated with immunotherapy.