Diagnosis-to-Treatment Interval Associated With Prognostic Factors in DLBCL
A recent study found that diagnosis-to-treatment interval may be linked with prognostic clinical factors and event-free survival in newly diagnosed diffuse large B-cell lymphoma (DLBCL).
Additionally, the study found that diagnosis-to-treatment interval has significant implications for bias in clinical trials.
A common concern in the oncology community is that patients with clinically aggressive disease may not be inclined to enroll in DLBCL trials due to the consent process and the inability to delay therapy for eligibility evaluation.
Grzegorz S Nowakowski, MD, Mayo Clinical (Rochester, MN), and colleagues conducted a study to examine the diagnosis-to-treatment interval and any potential associations with clinical factors and outcome in a clinic-based observational cohort of patients in the United States with DLBCL. Among the patients prospectively enrolled in the trial were those in the University of Iowa and Mayo Clinic Specialized Programs of Research Excellence Molecular Epidemiology Resource (MER; n = 986) and those in the Lymphoma Study Association (LYSA) LNH-2003 clinical trials program (n = 1444).
Patients received anthracycline-based immunochemotherapy at the time of initial diagnosis. Associations of diagnosis-to-treatment interval with clinical factors and outcome were examined, and outcome was assessed by utilizing event-free survival at 24 months from diagnosis (EFS24).
Results of the study were validated in an independent, clinical trial-based cohort from Europe and published in the Journal of Clinical Oncology (online April 19, 2018; doi:10.1200/JCO.2017.76.5198).
Researchers reported the median diagnosis-to-treatment interval was 15 days in the MER patients and 23 days in the LYSA patients. Shorter diagnosis-to-treatment interval was significantly associated with adverse clinical factors (ie, elevated lactate dehydrogenase levels, poor performance status, B symptoms, and higher International Prognostic Index) in both cohorts of patients (P .001). Furthermore, longer diagnosis-to-treatment interval was associated with improved EFS24 in both the MER and LYSA patients.
Researchers noted that associations with EFS24 remained significant after adjusting for International Prognostic Index.
“Diagnosis-to-treatment interval is strongly associated with prognostic clinical factors and outcome in newly diagnosed DLBCL,” Dr Nowakowski and colleagues concluded. “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.”—Zachary Bessette