Clinical activity of rituximab in gastric marginal zone non-Hodgkin's lymphoma resistant to or not eligible for anti-Helicobacter pylori therapy

PURPOSE: Preliminary results using rituximab in extranodal marginal zone (MALT) non-Hodgkin's lymphoma (NHL) patients seem to indicate a relevant clinical activity. Aim of the present study is to investigate the efficacy of conventional weekly treatment using rituximab in gastric MALT NHL patients resistant/refractory or not suitable for eradication treatment, and to evaluate the relevance of the t(11; 18)(q21; q21) translocation and its possible role as a predictive criteria of response. PATIENTS AND METHODS: Twenty-seven patients presenting with gastric MALT NHL at any stage, relapsed/refractory to initial treatment or not suitable for eradication were treated with rituximab in a weekly conventional schedule and evaluated for response and relapse. Flourescence in situ hybridization (FISH) analysis for the presence of 18q21 translocation was performed in 21 patients and was evaluated with clinical outcome. RESULTS: Among the 26 evaluated patients, 20 (77%) achieved an objective response. Twelve patients (46%) had a pathological and clinical complete remission, and eight (31%) had a partial response. With a median follow-up of 33 months, only two patients relapsed at 26 and 14 months, respectively. No correlation was founded between FISH analysis and response or relapse. CONCLUSION: Our experience seems to confirm the clinical activity of rituximab in gastric MALT NHL patients resistant/refractory to antibiotics treatment or not presenting with clinical evidence of Helicobacter pylori infection. The t(11; 18)(q21; q21) translocation seems not to be a predictive marker to response or to subsequent relapse.