Updating survival estimates in patients with chronic lymphocytic leukemia or small lymphocytic lymphoma (CLL/SLL) based on treatment-free interval length

Abstract

We hypothesized that the length of treatment-free survival following (a) initial diagnosis and (b) first-line treatment would be associated with improved subsequent five-year relative survival (RS5) in patients with chronic lymphocytic leukemia or small lymphocytic lymphoma (CLL/SLL). 19,879 patients incident CLL/SLL cases (median age = 76 years) were identified from SEER-Medicare. RS5 improved from 0.73 (95% CI: 0.72, 0.74) at diagnosis to 0.81 (95% CI: 0.80, 0.82) at year 1 and 0.89 (95% CI: 0.83, 0.96) at year 10 among those who had not received treatment. In our analysis of survival patterns following first-line treatment, RS5 improved from 0.55 (95% CI: 0.53, 0.57) at initiation of first-line treatment to 0.84 (95% CI: 0.75, 0.92) among patients who had not been retreated at year 5 following first-line therapy. Longer periods of treatment-free survival following initial diagnosis and first-line treatment were both predictive of meaningfully improved prognosis in CLL/SLL patients.

Keywords:

• Leukemia
• lymphocytic
• chronic
• B-cell
• lymphoma
• non-Hodgkin
• survival
• prognosis
• epidemiology
• Medicare

Potential conflict of interest

Disclosure forms provided by the authors are available with the full text of this article online at https://doi.org/10.1080/10428194.2017.1349905.

Additional information

Funding

Research reported in this publication was supported by the National Cancer Institute of the National Institutes of Health under Award Number P50 CA097274, the University of Iowa Holden Comprehensive Cancer Center (HCCC) Population Research Core, which is supported in part by P30 CA086862, and by a Cancer & Aging Pilot Project Award from the University of Iowa HCCC and Center on Aging.