In very-elderly diffuse large B-cell lymphoma (DLBCL) patients, treatment intensities must be lowered due to the risks of comorbidities and organ function deterioration, and treatment outcomes are worse compared to younger patients. Very-elderly patients are often excluded from DLBCL clinical trials, and optimal treatments and dosages are not established. In this clinical trial, we examined the efficacy and safety of 6 courses of R-mini CHP therapy (cf., CHOP [cyclophosphamide, doxorubicin, vincristine, and prednisone]) in which vincristine is omitted to avoid the peripheral neuropathy that reduces elderly patients’ quality of life, as remission induction therapy in DLBCL patients aged≥80 years.