AbstractPurposeWhile the prognosis of patients with cancer has improved, the time burden of treatment has recently been recognized as time toxicity; although, the actual clinical situation remains largely unexplored. This retrospective study aimed to elucidate the time toxicity of rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone (R-CHOP) in patients with B-cell lymphoma and the factors influencing it.MethodsWe used a nationwide hospital-based database between January 2010 and November 2021 in Japan. We extracted the claims data of patients with diffuse large B-cell lymphoma and follicular lymphoma who were hospitalized and/or visited hospitals for chemotherapy.ResultsAmong the 7760 R-CHOP administered to 2006 patients, the rate of outpatient therapy increased over time (2010–2015: 17.9%; 2016–2021: 31.8%). In 2016, the median length of hospitalization was the shortest at 13 days (IQR 8–19), which coincided with the peak use of pegylated granulocyte colony-stimulating factor (Peg-G-CSF) during hospitalization in 2015–2016, likely driven by changes in the insurance system. In multivariate analysis, the factors associated with longer hospital stays were older age and poor activities of daily living, whereas the use of Peg-G-CSF, a reduced-dose regimen, and treatment at cancer-designated hospitals were associated with shorter stays.ConclusionThe time toxicity of R-CHOP has improved and may be influenced by the patient’s condition, adequate supportive care, changes in the insurance system, and center-specific treatment proficiency.