Objective: To determine the incidence, time-course, and risk factors associated with the development of thromboembolism (VTE) in a population-based study of women with ovarian cancer.
Methods: Using the California Cancer Registry, cases diagnosed with ovarian cancer for a 6-year period were identified. These cases were linked with the California Patient Discharge Data Set to determine the incidence of VTE. Proportional hazards modeling was performed to analyze the strength of specified risk factors to predict development of VTE or death within 2 years.
Results: Among 13,031 cases with ovarian cancer, 5.2% were diagnosed with a VTE event within 24 months after diagnosis. The cumulative incidence varied from 1.4% among women with local stage disease to 6.7% among women with advanced disease. The person-time incidence rate of VTE decreased over time, with the highest rate noted during the first 3 months. In a multivariate model, significant risk factors for VTE included advancing age, increasing number of chronic comorbid conditions, more advanced cancer stage, invasive histology, and absence of any major surgery. For all stages of cancer, development of VTE within 2 years was a significant risk factor for decreased survival, and the magnitude of the risk was greatest among the cases diagnosed with localized disease (HR 4.7, 95% CI: 2.3-9.5).
Conclusions: VTE occurred in a significant proportion of ovarian cancer patients and adversely impacted survival, particularly among cases with local or regional stage cancer.