Treatment With [90]Y-Ibritumomab Tiuxetan Versus no Treatment in Patients With Follicular Non Hodgkin Lymphoma (Stage III or IV) Having Achieved a Partial or Complete Remission After First Line Chemotherapy

Inclusion Criteria: Non Hodgkin Lymphoma stage III or IV at timepoint of diagnosis Patients who have achieved a remission after first line chemotherapy No less than 6 weeks and no more than 12 weeks since last dose of chemotherapy older than 18 years written informed consent Exclusion Criteria: Any other anticancer treatment for NHL except the preceding first line chemotherapy Prior radiation therapy Patients who have not recovered from the toxic effects of the first line chemotherapy Any other cancer or history of cancer less than 10 years ago Patients with known HIV positivity patients with pleural effusion or ascites female patients who are pregnant or breast feeding (women of childbearing potential must have a negative serum pregnancy test at study entry) Adults not employing an effective method of birth control during study treatment and 12 months thereafter Patients unable or unwilling to comply with protocol