Khorana Score (VTE risk in cancer patients starting chemotherapy)
VTE risk in ambulatory cancer patients before starting systemic chemotherapy.
About this calculator
The Khorana score estimates VTE risk in cancer patients before chemotherapy. Developed by Khorana et al. (Blood, 2008) in 4066 patients. Five variables: cancer site (stomach/pancreas 2; lung/lymphoma/gynecologic/urinary 1), platelets >=350×10⁹/L (1), hemoglobin <100 g/L or erythropoiesis-stimulating agent use (1), leukocytes >11×10⁹/L (1), BMI >=35 (1). Maximum 6. Interpretation. 0 – low risk (2.5-month VTE rate 0.3-0.8%), no prophylaxis. 1-2 – intermediate (1.8-2%), individual decision. >=3 – high risk (6.7-7.1%), outpatient thromboprophylaxis indicated – apixaban 2.5 mg twice daily or rivaroxaban 10 mg once daily for 6 months (ASCO 2023, NCCN 2024). Clinical use. Pre-chemotherapy stratification. Decision on primary thromboprophylaxis in outpatients. Hospitalized oncology patients receive LMWH prophylaxis regardless of Khorana – inpatient admission itself is a risk factor. Clinical trials. AVERT (NEJM 2019) and CASSINI (NEJM 2019) showed reduction of symptomatic VTE with apixaban/rivaroxaban in patients with Khorana >=2 without major bleeding increase. Based on these, ASCO 2023 expanded the recommendation to Khorana >=2. Limitations. Does not capture multimodal therapy (PD-1/PD-L1 immunotherapy raises VTE risk independent of Khorana). Not validated for anti-VEGF (bevacizumab) – different recommendations apply. Does not separate primary prophylaxis from treatment of established VTE. In GI cancer, active bleeding, platelets <50×10⁹/L prophylaxis is contraindicated even with high Khorana.
Source
Formula version: khorana-2008-nccn-2024-v1