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

These are peer-reviewed supplementary figures and tables for the article 'Treatment patterns and economic burden of bacterial vaginosis among commercially insured women in the USA' published in the Journal of Comparative Effectiveness Research.

• Supplementary Figure 1: Timing of events for the treated and untreated subgroups
• Supplementary Figure 2: The covariate balance between the treated and untreated subgroups
• Supplementary Table 1: Procedure and NDC codes for CLL treatments
• Supplementary Table 2: Diagnosis codes for SPMs

Aim: 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 & methods: 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). Results: 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 < 0.001). A significantly lower percentage of patients who received targeted

therapy developed a SPM (p < 0.05) versus patients treated with anti-CD20 + chemotherapy. Conclusion:

Findings indicate that treatment type and timing can affect SPM development in patients with CLL.

Combined with previous findings, this can help inform best practices in monitoring for SPM in patients

with CLL.