Single 4-Dose Rituximab Treatment for Low-Tumor Burden Follicular Lymphoma (FL): Survival Analyses with a Follow-Up (F/Up) of at Least 5 Years.

Rituximab alone may be given as initial treatment for FL either as a single treatment or as an induction treatment followed by a maintenance. In 2002, we have reported the response rates and progression-free survival (PFS) of 49 patients (pts) treated with 4 weekly 375 mg/m² doses of rituximab (

Best response rate was 80% with 49% CR/CR_u and 31% PR, and response was maintained in 34% without further treatment after at least 5 years. Median F/Up was 60 months. The median PFS was 18 months. Among these 49 pts, only 3 pts died (2 from NHL, 1 from lung carcinoma).

Among the 32 pts who were bcl-2 positive in the blood and/or the bone marrow before treatment with rituximab, 10 (33%) became negative and 20 (67%) remained positive at d50. 6 (60%) relapsed among the former and 15 (75%) among the latter. Median PFS was 37 months for pts who became bcl-2 negative and 14 months for those who remained positive (p[log-rank test] = 0.10). Among the 4 patients who had information on molecular biology who did not relapse after a 5-year F/Up, 3 were bcl-2 negative and 1 was bcl-2 positive.

The long F/Up of these pts (i) confirms the median PFS of 18 months for all pts and the median relapse-free survival of 27 months for best responders (ii) shows that some patients (i.e. 28% of all pts and 34 % of responders) may have a relapse-free survival longer than 5 years after a single first line treatment with rituximab in monotherapy ; (iii) shows an excellent overall survival (only 3 death (6%) during the study) in these FL pts. These results confirm the relevance of on-going trials comparing a maintenance treatment with rituximab and treatment at the time of relapse.