Is extensive screening for cancer in idiopathic venous thromboembolism warranted?

Summary. Background: Patients with a first episode of idiopathic venous thromboembolism (IVTE) have an estimated 10% incidence of cancer within 12 months after diagnosis. However, the utility of screening for cancer in this population is controversial. Methods: In this prospective concurrently controlled cohort study, limited and extensive cancer screening strategies were compared. All 630 patients underwent baseline screening consisting of history, physical examination, basic laboratory tests and chest X‐ray. In the extensive screening group abdominal and chest CT scan and mammography were added. Outcomes were incidence and curability of cancer, and cancer‐related and overall mortality. Results: In 12 of the 342 (3.5%) patients in the extensive screening group malignancy was diagnosed at baseline compared with 2.4% (seven of 288 patients) in the limited screening group. Extensive screening detected six additional cancers (2.0%; 95% CI, 0.74–4.3), of which three were potentially curable. During a median 2.5 years of follow‐up, cancer was diagnosed in 3.7% and 5.0% in the extensive and limited screening groups, respectively. In the extensive screening group 26 patients (7.6%) died compared with 24 (8.3%) in the limited screening group; adjusted hazard ratio 1.22 (95% CI, 0.69–2.22). Of these deaths 17 (5.0%) in the extensive screening group and 8 (2.8%) in the limited screening group were cancer related; adjusted hazard ratio 1.79 (95% CI, 0.74–4.35). Conclusions: The low yield of extensive screening and lack of survival benefit do not support routine screening for cancer with abdominal and chest CT scan and mammography in patients with a first episode of IVTE.