Venous thromboembolism in patients with chronic lymphocytic leukemia

Venous thromboembolism (VTE) is a major cause of morbidity and mortality in patients (pts) with malignant tumors. Increased risk of VTE is well described in a variety of hematologic malignancies; however, data regarding VTE in chronic lymphocytic leukemia (CLL) is very limited.

We retrospectively analyzed clinical and laboratory data of 346 consecutive pts with CLL followed up at 4th Department of Internal Medicine - Hematology, University Hospital, Hradec Kralove, Czech Republic, diagnosed between 1999 and 2011 (males, 64%; median age, 64 years; low/intermediate/high Rai modified risk in 41/47/12%).

After a median follow-up of 72 months (range, 26-138), at least one episode of VTE occurred in 38 patients (11%). VTE developed after a median of 34 months from CLL diagnosis. Incidence of VTE was 1.67% per patient year of follow-up. There was a high proportion of unfavourable prognostic factors (advanced Rai stages, unmutated IgVH genes, unfavourable cytogenetics) in pts with VTE. The presence of 0/1/2/3 additional risk factors for VTE was identified in 2/16/14/6 patients. The most common risk factors for VTE besides age (n=24) were corticosteroid therapy (n=13), other malignancies (n=9) and obesity (n=7). Recurrence of VTE was diagnosed in 7 pts. Performance status ≥ 2 and inherited thrombophilia were significant risk factors for VTE development in univariate and multivariate analysis. VTE was not associated with shorter overall survival.

Based on our results, VTE is a relatively frequent complication in patients with CLL. Although most patients had other known risk factors for VTE including CLL treatment, 29% had no risk factors or only age ≥ 60 years. These findings demonstrate the possible role of CLL in the development of VTE.