Reduced Dose Intensities of Doxorubicin in Elderly Patients with DLBCL in Rituximab Era

PURPOSE: The dose intensity of doxorubicin (DID) is important to the survival of diffuse large B cell lymphoma (DLBCL) patients. However, due to expected toxicities, most elderly patients cannot receive full doses of anthracyclines. The purpose of this study was to evaluate the effect of DID on the survival of elderly DLBCL patients (age ≥ 70 years) in the rituximab era. MATERIALS AND METHODS: We analyzed 433 DLBCL patients who were treated with R-CHOP between December 2003 and October 2011 at the Seoul National University Hospital. Of these patients, 19.2% were aged ≥ 70 years. We analyzed the survival outcomes according to DID. RESULTS: Significantly poorer overall survival (OS) was observed for patients aged ≥ 70 years (2-year OS rate: 59.9% vs. 84.2%; p < 0.001). DID ≤ 10 mg/m(2)/wk had a significant effect on the OS and progression-free survival (PFS) in elderly patients (2-year OS rate: 40.0% in DID ≤ 10 mg/m(2)/wk vs. 62.6% in DID > 10 mg/m(2)/wk; p=0.031; 2-year PFS: 35.0% vs. 65.7%; p=0.036). The OS on each 1.7 mg/m(2)/wk doxorubicin increment above 10 mg/m(2)/wk in elderly patients was not significant among the groups (2-year OS rate: 75.0% in DID 10.0-11.7 mg/m(2)/wk vs. 66.7% in DID 15.0-16.7 mg/m(2)/wk; p=0.859). Treatment related mortality was not related to DID. CONCLUSION: DID can be reduced up to 10 mg/m(2)/wk in elderly DLBCL patients in the rituximab era. Maintenance of DID > 10 mg/m(2)/wk and judicious selection of elderly patients who are tolerant to DID is necessary.