Risk of second primary malignancies in patients with chronic lymphocytic leukemia: a population-based study in the Netherlands, 1989-2019
Lina van der Straten, Mark‐David Levin, Manette A. W. Dinnessen, Otto Visser, Eduardus F. M. Posthuma, Jeanette K. Doorduijn, Anton W. Langerak, Arnon P. Kater, Avinash G. Dinmohamed
Abstract
The longevity of patients with chronic lymphocytic leukemia (CLL) has improved progressively over the past decades, making it essential to understand long-term health outcomes, such as second primary malignancies (SPMs). Therefore, this nationwide, population-based study assessed the risk of SPM development in CLL patients diagnosed during 1989-2019 in the Netherlands compared to the expected number of malignancies in an age-, sex-, and period-matched group from the general Dutch population. In 24,815 CLL patients followed for 162,698.49 person-years, 4369 SPMs were diagnosed with a standardized incidence ratio (SIR) of 1.63 (95% confidence interval [CI] 1.59-1.68). This elevated risk was observed for solid (SIR, 1.67; 95% CI, 1.65-1.75) and hematological SPMs (SIR 1.42; 95% CI, 1.24-1.62). The highest risk for SPMs was noted beyond five years post-diagnosis (SIR, 1.70; 95% CI, 1.62-1.77), for male individuals (SIR, 1.70; 95% CI, 1.64-1.77), and patients aged 18-69 years (SIR, 1.92; 95% CI, 1.79-2.05). The risk of SPMs was higher in CLL patients who received anti-neoplastic therapy (SIR, 2.12; 95% CI, 1.96-2.28), as compared with those who did not (SIR, 1.58; 95% CI, 1.53-1.63). Routine surveillance activities and tailored interventions to counteract the increased morbidity and excess mortality associated with SPMs are essential for improving long-term outcomes in CLL patients.