Dose-adjusted EPOCH-R vs. R-CHOP in frontline management of Waldeyer's ring diffuse large B-cell lymphoma: a retrospective study from a single institution.

BACKGROUND: To compare the efficacy and safety of dose-adjusted etoposide, prednisone, vincristine, cyclophosphamide, and doxorubicin plus rituximab (DA-EPOCH-R) with standard rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone (R-CHOP) in Waldeyer's ring diffuse large B-cell lymphoma (WR-DLBCL) at a single institution. METHODS: This retrospective study included 115 newly diagnosed patients with WR-DLBCL, of whom 68 patients received R-CHOP, and 47 patients received DA-EPOCH-R as their first-line treatment. The baseline features of the two groups were well balanced using a 1:1 propensity score matching method, and a total of 84 cases were obtained, including respective 42 cases in the R-CHOP and DA-EPOCH-R groups, for further survival and prognosis analysis. The primary objectives included progression-free survival (PFS) and overall survival (OS). RESULTS: During a median follow-up of 45 months, there were nine (21.4%) deaths in the R-CHOP group and two (4.8%) in the DA-EPOCH-R group. Kaplan-Meier analysis showed statistically significant improvements in PFS and OS in patients with DA-EPOCH-R compared with those treated with R-CHOP (log-rank test, P  = 0.025 and P  = 0.035, respectively). The 2-year PFS and OS rates in the DA-EPOCH-R group were 90.1% (95% confidence interval [CI]: 81.4-99.8%) and 95.2% (95% CI: 89.0-100.0%), respectively, and 80.5% (95% CI: 69.3-93.6%) and 90.5% (95% CI: 52.8-99.8%) in the R-CHOP group. Patients without B symptoms and elevated lactate dehydrogenase levels had a higher PFS in the DA-EPOCH-R group, with P values of 0.038 (hazard ratio [HR]: 0.11; 95% CI: 0.01-0.88) and 0.042 (HR: 0.19; 95% CI: 0.04-0.94), respectively. There were no statistically significant differences in clinical responses and treatment-related toxicities between the two groups. CONCLUSION: Compared with patients received R-CHOP, those treated by DA-EPOCH-R had superior PFS, OS, and controlled toxicity in patients with WR-DLBCL.