Severe neutropenia and relative dose intensity among patients <65 and ≥65 years with non-Hodgkin's lymphoma receiving CHOP-based chemotherapy

Purpose: The objective of this study was to describe the incidence of grade 3/4 neutropenia, patterns of chemotherapy treatment, and granulocyte colony-stimulating factor (G-CSF) use patterns among patients with non-Hodgkin's lymphoma (NHL) <65 and ≥65 years. Methods: This retrospective, observational study included adult patients with NHL who received cyclophosphamide, doxorubicin, vincristine, and prednisone±rituximab (CHOP±R) from January 2006 to June 2010. Results: A total of 1,579 patients were included, with 54.1 % <65 years and 45.9 % ≥65 years. Most received CHOP-R on a Q3W schedule. Among patients <65 years, the incidence of grade 3/4 neutropenia was 52.3 %, the mean relative dose intensity (RDI) was 80.4 %, and the incidences of dose delays and reductions were 26.5 and 9.6 %, respectively. Among patients ≥65 years, the incidence of grade 3/4 neutropenia was 63.2 %, the mean RDI was 73.9 %, and the incidences of dose delays and reductions were 24.6 and 24.9 %, respectively. Most patients (86.9 %) received G-CSF. Among patients <65 years, 71.9, 17.4, and 10.7 % first received G-CSF as primary prophylaxis, secondary prophylaxis, or treatment, respectively. Among patients ≥65 years, 80.1, 11.6, and 8.3 % first received G-CSF as primary prophylaxis, secondary prophylaxis, or treatment, respectively. Conclusions: Chemotherapy regimens and schedules were similar among age groups. Grade 3/4 neutropenia, reduced RDI, and dose delays were common in both age groups, though patients ≥65 years had a higher incidence of dose reductions. In spite of these similarities, patients <65 years were less likely to receive primary prophylactic G-CSF. Thus, careful assessment of neutropenia risk factors is needed across age groups to determine appropriate G-CSF use and support planned chemotherapy.