Zevalin Post-marketing Surveillance in Japan

This study is a regulatory post marketing surveillance in Japan, and it is a local prospective and observational study of patients who have received Zevalin for relapsed or refractory, CD20+, low grade B-cell non-Hodgkin's lymphoma and Mantle cell lymphoma. The objective of this study is to assess safety and efficacy of using Zevalin in clinical practice. This study is also all case investigation of which the enrollment period is five years, and all patients who received Zevalin will be recruited and followed 13 weeks after the administration.