The role of early investigation for occult malignancy in unprovoked venous thromboembolism remains unclear. NICE have suggested that investigation with abdominal/pelvic CT, urinalysis and mammograms in over 40 year olds with unprovoked VTE could be performed. However this is a suggestion rather than a definite recommendation¹.

The evidence shows that although occult malignancy may be identified at an earlier stage, it does not change the overall mortality rate. Furthermore there is no clear consensus on the best investigations to perform. The earlier detection of malignancy has to be balanced with the potential clinical and emotional implications for patients that may have incidental abnormalities detected on investigation which do not prove to be malignant.

Therefore investigation for occult malignancy in unprovoked VTE should be on a case by case basis and be symptom directed.  This should involve full clinical history and examination, basic laboratory testing, chest x-ray, urinalysis and any age-appropriate cancer screening if not already performed. Indeed studies have shown that this strategy identifies most cases of malignancy at diagnosis as many have abnormal clinical findings at presentation². In addition recent evidence has shown that screening does not alter time to diagnosis of malignancy nor add in a mortality benefit³.

Mention should be made of higher risk groups in which more extensive investigation for underlying malignancy could be justified. Those include further VTE on established anticoagulation, recurrent VTE within a short time frame, bilateral DVT, patients with a very high D-dimer (e.g. >5,000 ng/mL) at VTE diagnosis and those with hepatic/portal vein thrombosis.

Therefore, the GG&C VTE committee do not recommend routine extensive screening. Rather, investigation for occult malignancy in VTE should be directed by, and be appropriate to, clinical signs and symptoms presented at diagnosis. Eligible patients should be encouraged to participate in all cancer screening programs relevant to their age & sex.

References

1. Chong L-Y, Fenu E, Stansby G, Hodgkinson S. Management of venous thromboembolic diseases and the role of thrombophilia testing: summary of NICE guidance. BMJ 2012;344(jun27 1):e3979–9.
2. Sørensen HT, Mellemkjaer L, Olsen JH, Baron JA. Prognosis of cancers associated with venous thromboembolism. N Engl J Med 2000;343(25):1846–50.
3. Carrier M, Lazo-Langner A, Shivakumar S, et al. Screening for Occult Cancer in Unprovoked Venous Thromboembolism. N Engl J Med 2015; :150622050020006.