For oligo or non-secretory multiple myeloma, measurable disease is defined by the presence of soft tissue (not bone) plasmacytomas as determined by clinical examination or applicable radiographs (i.e. MRI, CT-Scan). In patients with oligo-secretory multiple myeloma, the serum and/or urine M-protein measurements are very low and difficult to follow for response assessment. In patients with non-secretory multiple myeloma, there is no M-protein in serum or urine.