Diagnosis-to-Treatment Interval and Outcome in Newly Diagnosed DLBCL
In a study reported in the Journal of Clinical Oncology, Maurer et al found that a shorter interval between diagnosis and treatment was associated with adverse prognostic features and that a longer interval was associated with greater event-free survival in the first-line treatment of diffuse large B-cell lymphoma (DLBCL) in recent clinical trials, raising the issue of selection bias in this setting.
Study Details
The study included patients prospectively enrolled in the University of Iowa and Mayo Clinic Specialized Programs of Research Excellence Molecular Epidemiology Resource (MER; n = 986) or the Lymphoma Study Association (LYSA) LNH-2003 clinical trials program (n = 1,444). All patients received anthracycline-based immunochemotherapy at initial diagnosis. The associations between diagnosis-to-treatment interval and clinical factors and outcome were assessed, with the primary outcome measure being event-free survival at 24 months from diagnosis.
Diagnosis-to-Treatment Interval
The median interval from diagnosis to treatment was 15 days (range = 0–115 days) in the MER cohort and 23 days (range = 0–215 days) in the LYSA cohort. A shorter interval was significantly associated with adverse clinical factors; among patients in both cohorts, patients initiating treatment at ≤ 14 days vs ≥ 15 days were more likely to have elevated lactate dehydrogenase levels (68% vs 42%, P < .001), advanced-stage disease (III or IV, 74% vs 56%, P < .001), worse Eastern Cooperative Oncology Group performance status (≥ 2, 28% vs 10%, P < .001), more frequent B symptoms (33% vs 18%, P <.001), more bulky (≥ 10 cm) disease (14% vs 8%, P = .0030), and a higher age-adjusted International Prognostic Index (IPI) score (58% vs 33%, P < .001).
Event-Free Survival
A longer diagnosis-to-treatment interval was associated with improved event-free survival at 24 months in unadjusted analysis (per-week odds ratio [OR] = 0.77, P < .001) and analysis adjusted for IPI score (per-week OR = 0.83, P < .001) in the MER cohort, and in unadjusted analysis (per-week OR = 0.88, P < .001) and IPI-adjusted analysis (per-week OR = 0.93, P = .0050) in the LYSA cohort.
The investigators concluded, “[Diagnosis-to-treatment interval] is strongly associated with prognostic clinical factors and outcome in newly diagnosed DLBCL. [Diagnosis-to-treatment interval] should be reported in all clinical trials of newly diagnosed DLBCL, and future trials should take steps to avoid selection bias due to treatment delay.”
The study was supported in part by grants from the National Cancer Institute and Henry J. Predolin Foundation.
Grzegorz S. Nowakowski, MD, of the Division of Hematology, Mayo Clinic, Rochester, is the corresponding author for the Journal of Clinical Oncology article.
The content in this post has not been reviewed by the American Society of Clinical Oncology, Inc. (ASCO®) and does not necessarily reflect the ideas and opinions of ASCO®.
