Background: Chronic lymphocytic leukaemia (CLL) patients have an increased risk of other malignancies. This may be due to surveillance bias, treatment or immunosuppression.
Methods: Cohort study of 612 consecutively diagnosed CLL patients in a Canadian province, with comparisons to follicular lymphoma (FL) patients.
Results: Treated CLL patients had a 1.7-fold increased risk of second cancers compared with untreated CLL patients. As compared with untreated FL patients, untreated CLL patients had a two-fold increased incidence of second malignancies.
Conclusion: Chronic lymphocytic leukaemia patients have an inherent predisposition to second cancers and the incidence is further increased by treatment.