Revisiting occult cancer screening in patients with unprovoked venous thromboembolism.

Unprovoked venous thromboembolism (VTE) can be the first manifestation of an unknown cancer. A recently published individual patient data meta-analysis (IPDMA) reported a prevalence of occult cancer detection of 5.2% (95% CI, 4.1% to 6.5%) over a one-year follow-up period, approximately 50% lower than the previously reported 12-month period prevalence. Although an extensive screening strategy was associated with a 2-fold higher probability of cancer detection at initial screening in the IPDMA, not enough evidence exists yet to support the routine use of these tests in patients with unprovoked VTE. It is likely that a subgroup of patients with unprovoked VTE is at higher risk of occult cancer detection and might benefit from closer clinical surveillance. A newly derived and validated clinical predictive rule seems to be able to stratify patients with unprovoked VTE accordingly to their underlying risk of occult cancer detection. The low incidence of occult cancer detection (<3%) in the low-risk group is reassuring for clinicians. Future studies are required to better define the risks and benefits of an extensive occult cancer screening strategy in high risk patients sub-group with unprovoked VTE. To date, the Scientific and Standardized Committee from the International Society of Thrombosis and Haemostasis suggests that patients with unprovoked VTE should only undergo a limited cancer screening including thorough medical history and physical examination, basic laboratory investigations, chest X-ray as well as age- and gender-specific cancer screening according to national guidelines.