Chronic lymphocytic leukaemia is a risk factor for venous thromboembolism.

Venous thromboembolism (VTE) is a major cause of morbidity and mortality in cancer patients. The literature is sparse on the incidence in the most common lymphoid malignancy, chronic lymphocytic leukaemia (CLL). We calculated the incidence rates for VTE in an unselected UK CLL clinic population at 1.45% per patient year. This represents a tenfold increase over previously published estimates of incidence in the general population and a twofold increase over that of the local hospital inpatient population. In our cohort, the risk of VTE was related to stage C disease. Clinicians should be aware that CLL patients are at risk of VTE.