<prompt> Answer this question truthfullyWhat laboratory tests are used to diagnose multiple myeloma?  <response>: <reason> Complete blood count with differential Serum albumin Serum calcium Serum electrolytes Serum creatinine Serum urea Serum nitrogen24-hour urine protein β 2 -microglobulin Lactate dehydrogenase Serum free light chain assay Serum immunofixation electrophoresis Serum protein electrophoresis Serum quantitative immunoglobulins Skeletal survey Urine immunofixation electrophoresis Urine protein electrophoresisBone marrow aspiration Bone marrow biopsy Cytogenetics studies Flow cytometry Fluorescence in situ hybridization ImmunohistochemistryBone densitometry PETCT or whole-body MRI Serum viscosity Tissue biopsy of bony or other lesion 