- Progressive disease, defined as 25% increase in serum M-protein or Bence Jones protein (an absolute increase of 0.5 gram/dL serum M-protein or at least 200 mg/24 hours of urine light chain excretion). For non-secretory multiple myeloma, progressive disease is defined as bone marrow biopsy with >25% increase in plasma cells or an absolute increase of at least 10% over prior known level. Alternatively, development of new or worsening of existing lytic bone lesions or soft tissue plasmacytomas, or hypercalcemia or relapse from CR.