Cases corner – 54 years old with painful calf

2nd July 2019

James, a 54 year old man, presented to you with a 2 day history of an acutely painful left calf. He denied any preceding symptoms, injuries, immobility or any chest symptoms. He is usually fit and well. You screened for any risk factors for a thrombosis but find nothing. He is a non-smoker, not on any medication, and has no relevant family history. You referred to ambulatory care for a same day appointment for a query DVT (Deep Vein Thrombosis). The following week, the same patient presents for a review. He had a left leg DVT confirmed and had been started on rivaroxaban by the hospital and discharged. James asks you why he got the DVT?

  1. Reassure James that DVTs are common and he is on the best treatment
  2. Safety-net James and advise that if he develops any further symptoms to come back and see you
  3. Refer James to haematology for further evaluation
  4. Conduct a thorough assessment to find an underlying cause for the DVT

The correct answer here is that James should undergo a comprehensive assessment for an underlying malignancy. There are no indications from the history that this was a provoked DVT, or that James had any risk factors to predispose him to suffering from a DVT, nor was James a smoker. An assessment should be undertaken, including investigations or referral to further identify any underlying cause. In asymptomatic patients this can be exceptionally difficult to know where to start looking.

A new diagnosis of DVT is known to be associated with several cancers, including urogenital, breast, colorectal and lung cancer. NICE advises that we should carry out a further assessment for additional symptoms, signs or findings that may help to clarify which cancer is most likely and, to consider an urgent investigation or a suspected cancer pathway referral (for an appointment within 2 weeks).

A cohort study of 77,572 patients with VTE (venous thromboembolism) between 1981 and 2000, identified an increased risk of being diagnosed with a malignancy after a primary episode of VTE. This was higher in the first 12 months after a diagnosis of VTE, and persisted for a further two years after a VTE before returning to background levels of risk. The highest risk of cancer was in patients who had a VTE under 60, with a greater absolute risk of malignancy as patients get older in line with prevalence of malignancy. (One in 25 patients who are 60 to 75 year olds will develop cancer within one year).

This is not to be confused with patients with pre-existing malignancy who are at an increased risk of developing a DVT.

References

Murchison JT, Wylie L, Stockton DL. Excess risk of cancer in patients with primary venous thromboembolism: a national, population-based cohort study. Br J Cancer. 2004;91(1):92–95.