Assessment of second primary malignancies among treated and untreated patients with chronic lymphocytic leukemia using real-world data from the USA

• Published in: Journal of comparative effectiveness research 2024-02, Vol.13 (2), p.e230119-e230119
• Main Authors: Ailawadhi, Sikander, Ravelo, Arliene, Ng, Carmen D, Shah, Bonny, Lamarre, Neil, Wang, Rongrong, Eakle, Katherine, Biondo, Juliana Ml
• Format: Article
• Language: English
• Subjects: chronic lymphocytic leukemia; management; real-world; second primary malignancies; Short Report; treatment
• ISSN: 2042-6305; 2042-6313
• DOI: 10.57264/cer-2023-0119

Improved management of chronic lymphocytic leukemia (CLL) has resulted in a growing population of CLL survivors; these patients have a higher risk of developing second primary malignancies (SPMs) versus the general population. This retrospective cohort study aims to assess the timing, frequency, incidence and types of SPMs in treated and untreated patients with CLL in the USA, using the Surveillance, Epidemiology, and End Results (SEER) Medicare database, which links a nationally representative cancer registry with Medicare claims data. Patients aged ≥66 years with newly diagnosed CLL between 1 January 2010 and 31 December 2016, who were enrolled in Parts A and B of Medicare for ≥12 months pre-diagnosis of CLL were selected from the database. Patients were assessed for ≥36 months until the end of continuous enrollment in Medicare Parts A, B and D, a switch to a health maintenance organization, death, or end of the study period (December 2019). Of 3053 patients included in the analyses, 620 (20.3%) were treated and 2433 (79.7%) were untreated within 36 months of diagnosis. Overall, 638 (20.9%) patients developed a SPM, 26.8% of patients in the treated cohort and 19.4% of patients in the untreated cohort. The most common SPMs for both cohorts were squamous cell carcinoma and acute myeloid leukemia. Among the 166 treated patients who developed a SPM, a greater proportion developed their first SPM after treatment initiation versus those who developed their first SPM prior to treatment initiation (p