Sammanfattning
Introduction: Little is known about the prognosis of cancer discovered during or after an episode of venous thromboembolism. Material and methods: We linked the Danish National Re-gistry of Patients, the Danish Cancer Registry, and the Danish Mortality Files to obtain data on the survival of patients who received a diagnosis of cancer at the same time as or after an episode of venous thromboembolism. Their survival was compared with that of patients with cancer who did not have venous thromboembolism (control patients), who were matched in terms of type of cancer, age, sex, and year of diagnosis. Results: Of 668 patients who had cancer at the time of an episode of deep venous thromboembolism, 44.0 per cent of those with data on the spread of disease (563 patients) had distant metastases, as compared with 35.1 per cent of 5371 control patients with data on spread (prevalence ratio, 1.26; 95 per cent confidence interval, 1.13 to 1.40). In the group with cancer at the time of venous thromboembolism, the one-year survival rate was 12 per cent, as compared with 36 per cent in the control group, and the mortality ratio for the entire follow-up period was 2.20 (95 per cent confidence interval, 2.05 to 2.40). Patients in whom cancer was diagnosed within one year after an episode of venous thromboembolism had a slightly increased risk of distant metastases at the time of the diagnosis (prevalence ratio, 1.23 [95 per cent confidence interval, 1.08 to 1.40]) and a relatively low rate of survival at one year (38 per cent, vs. 47 per cent in the control group). Discussion: Cancer diagnosed at the same time as or within one year after an episode of venous thromboembolism is associated with an advanced stage of cancer and a poor prognosis.