Depth of neutrophil nadir after first cycle of R-CHOP predicts outcome in diffuse large B-cell lymphoma - a nationwide population-based cohort study.

We investigated if survival was predicted by nadir neutrophil counts after the first cycle of R-CHOP in patients with newly diagnosed diffuse large B-cell lymphoma (DLBCL). Neutrophil counts (10(9)/L) were categorized in four grades in the nadir time frame. Prognostic indices and comorbidity levels were calculated and used to adjust the Cox regression model. Kaplan-Meier and Cox regression methods were used to estimate and compare survival. We identified 965 patients. Grade 4 neutropenia was present in 432 (45%). Grade 0 patients had a 5-year overall survival of 67%, grade 1-2: 78%, grade 3: 64%, and grade 4: 57%. Compared with grade 0 adjusted hazard ratios (HR) for death were: 0.77 (95% CI 0.49-1.21) for grade 1-2, 1.18 (95% CI 0.82-1.71) for grade 3, and 1.33 (95% CI 1.02-1.73) for grade 4. Grade 4 neutropenia after the 1st cycle of chemotherapy predicted inferior outcome compared with grade 0 and 1-2. Grade 1-2 neutropenia seemed to have superior outcome.