First-line R-CVP versus R-CHOP induction immunochemotherapy for indolent lymphoma with rituximab maintenance. A multicentre, phase III randomized study by the Polish Lymphoma Research Group PLRG4.

R-CVP (cyclophosphamide, vincristine, prednisone) and R-CHOP (cyclophosphamide, doxorubicin, vincristine, prednisone + rituximab) are immunochemotherapy regimens frequently used for remission induction of indolent non-Hodgkin lymphomas (iNHLs). Rituximab maintenance (RM) significantly improves progression-free survival (PFS) in patients with complete/partial remission (CR/PR). Here we report the final results of a randomized study comparing R-CVP to R-CHOP both followed by RM. Untreated patients in need of systemic therapy with symptomatic and progressive iNHLs including follicular (FL) and marginal zone lymphoma (MZL), mucosa-associated lymphoid tissue (MALT), small lymphocytic (SLL), and lymphoplasmacytic (LPL) lymphoma were eligible. Patients were randomized to receive R-CVP or R-CHOP for eight cycles or until complete response (CR). All patients with CR/PR (partial response) received RM 375 mg/m(2) q 2 months for 12 cycles. Primary endpoint was event-free survival (EFS). Two-hundred and fifty patients [FL 42%, MZL/MALT 38%, LPL/ Waldenstrom Macroglobulinaemia (WM) 11%, SLL 9%] were enrolled and randomized (R-CHOP: 127, R-CVP: 123). Median age was 56 years (21-85), 44% were male, 90% were in stage III-IV, 43% of FL patients had a Follicular Lymphoma International Prognostic Index (FLIPI) score >/=3, and 33.4% of all patients had an IPI score >/=3. At the end of induction treatment, the CR/PR rate was 43.6/50.9% and 36.3/60.8% in the R-CHOP and R-CVP groups (P = 0.218) respectively. After a median follow-up of 67, 66, and 70 months, five-year EFS was 61% vs. 56% (not significant), progression-free survival (PFS) was 71% vs. 69% (not significant) and overall survival (OS) was 84% vs. 89% in the R-CHOP vs. the R-CVP arm respectively. Grade III/IV adverse events (65 vs. 22) occurred in 40 (33.1%) and 18 (15.3%) patients, P = 0.001; neutropenia in 16 (11.6%) and 4 (3.4%) patients, P = 0.017; infection in 14 (10.7%) and 3 (2.5%) patients,; P = 0.011; and a second neoplasm in three versus seven patients., in the R-CHOP and the R-CVP groups respectively. This multicentre randomized study with >five-year follow-up shows similar outcome in patients with indolent lymphoma in need of systemic therapy treated with R-CVP or R-CHOP immunochemotherapy and rituximab maintenance in both arms. The minor toxicity of the R-CVP regimen makes it a reasonable choice for induction treatment, leaving other active agents like doxorubicin or bendamustin for second-line therapy.