For patients with limited disease (R2 stage III) it is tested whether the event-free survival can be improved by adding rituximab to the standard chemotherapy. Two different treatment regimens will be evaluated in a randomized design: Patients in the standard arm will receive the standard chemotherapy. Patients of the rituximab plus arm will receive one dose of rituximab as monotherapeutic agent in the rituximab window R five days prior to the start of standard chemotherapy.