Maintenance Treatment with Rituximab in Follicular NHL.

Introduction: Preceding studies have shown that Rituximab ® prolongs relapsed free time (TFR) and response duration (RD) in follicular NHL (FNHL) when given either together with chemotherapy or alone as maintenance after therapy. The best schedule of maintenance with R still remains unknown.

Aim of study: to evaluate the relapsed free time in FNHL patients using R as maintenance after being treated with an induction schedule that included R.

Design: observational, prospective trial in previously patients with FL treated with chemotherapy + R in complete remission (CR).

Patients and methods: Since January 2002 to December 2005, 23 previously treated FL grade I or II patients with one R-chemotherapy line were included. At diagnosis baseline assessment: age, gender, clinical and physical exam, blood counts, serum and urine biochemistry, albumin, β2-microglobuline and LDH level, body scan, bone marrow biopsy. Patients were classified according to ECOG, clinical stage and FLIPI. Patients in complete remission (CR) after chemotherapy received R 375 mg/m² × 4 weekly every 6 months for 2 years. Re-staging studies were performed at every cycle: CR, partial remission (PR) and relapse ®. Toxicity events have been noted.

Statistical analysis: Overall survival (OS), relapsed free survival (RFS). Survival analysis was performed using Kaplan-Meier and Cox regression.

Results: Mean age 53.1 (35–75), 12 F/11M; ECOG 0(14), 1(8), 2(1); B symptoms 10; FLIPI score 0(2 patients), 1(10), 2(7), 3(4); stage I (2 patients), II(4), III(9), IV(8); grade I(10), II(13).

Therapy schedules: R-CHOP (69.5%), R-CHOP+RTP (8,7%), R-CMF (17,3%), R-CF (4.3%). At present 21,7% of patients have completed maintenance for two years, 30,4% have received 3 courses, 60,8% two and 1 100%. None of them have relapsed.

Adverse events: two patients were excluded because of grade 3–4 neutropenia and two referred erythema while infusion of R. OS: mean 28.2 months (10–61); RFS: mean 22 months (4–53).

Conclusions: R maintenance seems to be effective in FL. The tolerance has been good in most of the patients and only two cases presented severe adverse events, neutropenia, in those patients who had received QTP with fludarabine+R. It is necessary a longer follow-up to consider the magnitude of the effect obtained with R maintenance.