Prognosis of ovarian cancer subsequent to venous thromboembolism: a nationwide Danish cohort study

We identified 12,835 ovarian cancer patients diagnosed from 1980 to 2003 in the Danish Cancer Registry and obtained information on previous primary VTE diagnosis from the Danish National Hospital Discharge Registry. Ovarian cancer patients with previous VTE related to other cancers, surgery, or pregnancy were excluded. The vital status was determined by linking data to the Civil Registration System.We identified 50 ovarian cancer patients diagnosed less than 4 months after the VTE and 78 ovarian cancer patients diagnosed more than 4 months after the VTE diagnosis. Advanced stages tended to be more common among patients with VTE. One-year survivals were 44% and 54% among the two VTE groups, compared with 63% among patients without VTE. Adjusted (for age, calendar time, comorbidity, and FIGO-stage) mortality ratios were 1.7 (95% CI = 1.2–2.5) and 1.2 (95% CI = 0.8–1.7), respectively.Ovarian cancer diagnosed less than four months before VTE is associated with an advanced stage and a poorer prognosis.Ovarian cancer has a poor prognosis, and is frequently complicated by venous thromboembolic events (VTE) [1-3]. About 70% of ovarian cancers are diagnosed at an advanced stage [4,5], and advanced stage seems to be associated with higher risk of thromboembolic events [6]. Occasionally, VTE occurs prior to cancer diagnosis and research suggests that VTE may occur as a consequence of an underlying, undiagnosed cancer [7,8].A recently published, large population-based, study found that the incidence of unprovoked VTE was almost three times higher in the year preceding ovarian cancer diagnosis [9]. However, a paucity of research has investigated the effect of VTE on ovarian cancer prognosis. Sorensen et al [6] reported poorer prognosis among cancer patients following a thrombolic event, however they did not examine the prognosis for individual cancer sites. Moreover, it is not clear how the prognosis of ovarian cancer patients is affected by the timing of the thromboembolic even