Symptomatic and incidental venous thromboembolic disease are both associated with mortality in patients with prostate cancer

Abstract

Introduction: The association between malignancy and venous thromboembolic disease (VTE) is well established. The independent impact of VTE, both symptomatic and incidental, on survival in patients with prostate cancer is not known. We conducted a retrospective cohort study to evaluate the effect of VTE of survival in prostate cancer.

Methods: Data regarding clinical characteristics, treatment and outcomes of 453 consecutive prostate cancer patients were collected. Fisher exact (categorical variables) and t-test (continuous variables) were utilized to test associations with VTE and mortality. Survival was estimated using the Kaplan Meier method. A Cox regression model was used to model the mortality hazard ratio (HR).

Results: At diagnosis, 358 (83%) patients had early stage disease, 43 (10%) had locally advanced disease and 32 (7%) had metastatic disease. During the follow up period, 122 (27%) patients died and 41 (9%) developed VTE (33 deep vein thrombosis, 5 pulmonary embolism, and 3 patients with both DVT and PE). Twenty-five VTE events were symptomatic and 16 were incidentally diagnosed on CT scans obtained for other reasons. VTE was associated with increased mortality [HR 6.89 (4.29-11.08), p<0.001] in a multivariable analysis adjusted for cancer stage, performance status, treatments and co-morbidities. There was no difference in survival between patients who had symptomatic and incidental VTE.

Conclusion: Venous thromboembolic disease, both symptomatic and incidental, is a predictor of poor survival in patients with prostate cancer, especially those with advanced disease. Further studies are needed to evaluate the benefit of prophylactic and therapeutic anticoagulation in this population.

Figure 1. Kaplan Meier curve showing survival of patients who developed VTE with date of VTE as time origin.

Thirty-five of 41 (85.3%) patients with VTE died, 20 (57.1%) within 1 year.

Figure 2. Survival curves depicting survival (in months) for patients with and without venous thromboembolic disease (VTE).

Patients with VTE have higher mortality compared to patients without VTE [HR 6.89 (4.29–11.08), p<0.001]. There was no difference in mortality between patients with symptomatic or incidental VTE (p = 0.83).