1. Planned enrollment period One year (The planned number of patients to be enrolled is set to 400 patients.) Since all patients who are prescribed with Pomalyst are registered in RevMate®, enrollment using the Registration Form of the surveillance will be completed at the time when the planned number of patients to be enrolled is reached. During a period until conditions for approval are removed, a system enabling to retrospectively collect appropriate information based on patient data from RevMate® will be, as necessary, maintained.