Incidence, risk factors and prognostic impact of venous thromboembolism in patients with advanced non-small cell lung cancer receiving systemic therapy: a single-center retrospective analysis

To evaluate the incidence, timing, risk factors, and prognostic impact of venous thromboembolism (VTE) in patients with advanced non-small cell lung cancer (NSCLC) receiving systemic therapy. This single-center retrospective cohort study included 164 consecutive patients with pathologically confirmed stage IIIB-IV NSCLC who initiated systemic therapy between January 2021 and December 2025. VTE events were identified during follow-up and objectively confirmed by imaging. The cumulative incidence of VTE was estimated using a competing-risk approach, with death before VTE treated as a competing event. Risk factors for incident VTE were evaluated using cause-specific Cox regression. The prognostic impact of VTE was assessed using time-dependent Cox regression. During follow-up, 29 patients developed VTE, corresponding to a crude proportion of 17.68%. The median time to first VTE was 104 days, and 24 of 29 events (82.76%) occurred within 6 months. When death before VTE was treated as a competing event, the cumulative incidence of VTE was 8.00% at 3 months, 15.04% at 6 months, and 17.97% at 12 months. In multivariable cause-specific Cox analysis, higher baseline D-dimer was independently associated with incident VTE (HR 2.714, 95% CI 1.970–3.741, P < 0.001). In a sensitivity model, anti-angiogenic therapy was associated with higher VTE risk (HR 2.810, 95% CI 1.320–5.984, P = 0.007). In time-dependent Cox analysis, VTE was independently associated with worse OS (HR 4.464, 95% CI 2.162–9.216, P < 0.001), but not PFS (HR 1.622, 95% CI 0.811–3.245, P = 0.172). VTE was a relatively common and early complication in patients with advanced NSCLC receiving systemic therapy. Baseline D-dimer was the most consistent factor associated with incident VTE, and VTE was independently associated with worse OS when analyzed as a time-dependent event. These findings support early risk assessment and vigilant clinical surveillance for thrombosis in advanced NSCLC.