A Safety and Efficacy Study of Revlimid® 5 mg Capsules in Patients With Relapsed or Refractory Multiple Myeloma Who Have Received Long-term Treatment With it Under the Actual Condition of Use

To understand the safety and efficacy of Revlimid® 5 mg Capsules (hereinafter referred to as Revlimid) in patients with "relapsed or refractory multiple myeloma" (hereinafter referred to as "relapsed or refractory MM") who have received long-term treatment with it under the actual condition of use. 1. Planned registration period This period started on the date of initial marketing of Revlimid and will end at the time when the planned number of patients to be enrolled, 300, is reached (estimated to be approximately 1 year and 3 moths). 2. Planned surveillance period This period started on the date of initial marketing of Revlimid and will end 3 years after the last enrolled patient begins receiving Revlimid (estimated to be approximately 4 years and 3 months).