Impact of primary prophylaxis by pegfilgrastim in diffuse large B-cell lymphoma treated with R-CHOP.

Febrile neutropenia (FN) and chemotherapy-induced neutropenia (CIN) are common conditions that lead to dose reduction or delayed chemotherapy in patients with diffuse large B-cell lymphoma (DLBCL). Primary prophylaxis (PP) with long-acting granulocyte colony-stimulating factor (G-CSF) was introduced in South Korea in 2014. We aimed to investigate the effects of PP on FN-related hospitalization and death in patients with DLBCL receiving rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone (R-CHOP). Korean individuals (n = 11,491) with incident DLBCL and receiving R-CHOP during 2010-2016 were followed for FN-related hospitalization and mortality. The PP exposure group (patients during 2014-2015, n = 3599), patients during 2010-2016 (n = 11,491), and patients receiving PP during 2014-2016 (n = 4421) were compared with the non-exposure group (patients during July 2011-June 2013, n = 3017), patients in 2013 (n = 1596), and patients not receiving PP during 2014-2016 (n = 1289), respectively. Multivariable-adjusted hazard ratios (HRs) were calculated using the Cox model. The PP exposure group had 16% lower FN-related hospitalizations than the non-exposure group (HR = 0.84, P < 0.001). PP exposure had no beneficial effect on 1-year (HR = 0.98, P = 0.782) and 5-year mortality (HR = 0.97, P = 0.474). Patients in 2014 (HR = 0.85, P < 0.001), 2015 (HR = 0.88, P = 0.003), and 2016 (HR = 0.80, P < 0.001) had a decreased risk of FN-related hospitalizations compared with those in 2013. Among patients receiving their first R-CHOP cycle during 2014-2016, the HR for FN-related hospitalization was 0.90 (P = 0.014) in PP users compared with non-users. PP with a long-acting G-CSF lowered the FN-related hospitalization risk but did not benefit survival in patients with DLBCL receiving R-CHOP.