Uniform response criteria from the International Myeloma Working Group.12,13
| Response categories . | Response criteria . |
|---|---|
| Abbreviations: CR, complete response; VGPR, very good partial response; PR, partial response; MR, SD, PD, FLC, free light chain | |
| CR | No M protein in serum and urine; negative immunofixation and disappearance of any soft-tissue plasmacytomas and < 5% plasma cells in bone marrow. |
| VGPR | Serum and urine M-component detectable by immunofixation but not on electrophoresis or ≥90% or greater reduction in serum M-protein plus urine M-protein < 100 mg per 24 h. |
| PR | ≥ 50% reduction of serum M protein and reduction in 24-h urine M-protein by ≥90% or to < 200 mg per 24 h. If the serum and urine M-protein are unmeasurable a ≥50% decrease in the difference between involved and uninvolved FLC levels is required in place of the M-protein criteria. If serum and urine M-protein are unmeasurable, and serum free light assay is also unmeasurable, ≥50% reduction in bone marrow plasma cells is required in place of M-protein, provided baseline percentage was ≥30%. In addition to the above criteria, if present at baseline, ≥ 50% reduction in the size of soft-tissue plasmacytomas is also required. |
| MR | ≥ 25% but < 49% reduction of serum M protein and reduction in 24-h urine M-protein by 50%–89%, which still exceeds 200 mg per 24 h. In addition to the above criteria, if present at baseline, 25%–49% reduction in the size of soft-tissue plasmacytomas is also required. No increase in size or number of lytic bone lesions (development of compression fracture does not exclude response). |
| SD | Not meeting criteria for CR, VGPR, PR or progressive disease. |
| PD | Increase of 25% from lowest response value in serum M protein (absolute increase must be ≥ 0.5 100 mL) and/or urine M-component (absolute increase must be ≥ 200 mg/24 h) and/or bone marrow plasma cell percentage (absolute % must be 10%) and/or only in patients without measurable serum and urine M-protein levels: the difference between involved and uninvolved FLC levels (absolute increase must be >10 mg per 100 mL). OR Definite development of new bone lesions or soft-tissue plasmacytomas or definite increase in the size of existing bone lesions or soft-tissue plasmacytomas. OR Development of hypercalcemia (corrected serum calcium >11.5 mg per 100 mL) that can be attributed solely to the plasma cell proliferative disorder. |
| Response categories . | Response criteria . |
|---|---|
| Abbreviations: CR, complete response; VGPR, very good partial response; PR, partial response; MR, SD, PD, FLC, free light chain | |
| CR | No M protein in serum and urine; negative immunofixation and disappearance of any soft-tissue plasmacytomas and < 5% plasma cells in bone marrow. |
| VGPR | Serum and urine M-component detectable by immunofixation but not on electrophoresis or ≥90% or greater reduction in serum M-protein plus urine M-protein < 100 mg per 24 h. |
| PR | ≥ 50% reduction of serum M protein and reduction in 24-h urine M-protein by ≥90% or to < 200 mg per 24 h. If the serum and urine M-protein are unmeasurable a ≥50% decrease in the difference between involved and uninvolved FLC levels is required in place of the M-protein criteria. If serum and urine M-protein are unmeasurable, and serum free light assay is also unmeasurable, ≥50% reduction in bone marrow plasma cells is required in place of M-protein, provided baseline percentage was ≥30%. In addition to the above criteria, if present at baseline, ≥ 50% reduction in the size of soft-tissue plasmacytomas is also required. |
| MR | ≥ 25% but < 49% reduction of serum M protein and reduction in 24-h urine M-protein by 50%–89%, which still exceeds 200 mg per 24 h. In addition to the above criteria, if present at baseline, 25%–49% reduction in the size of soft-tissue plasmacytomas is also required. No increase in size or number of lytic bone lesions (development of compression fracture does not exclude response). |
| SD | Not meeting criteria for CR, VGPR, PR or progressive disease. |
| PD | Increase of 25% from lowest response value in serum M protein (absolute increase must be ≥ 0.5 100 mL) and/or urine M-component (absolute increase must be ≥ 200 mg/24 h) and/or bone marrow plasma cell percentage (absolute % must be 10%) and/or only in patients without measurable serum and urine M-protein levels: the difference between involved and uninvolved FLC levels (absolute increase must be >10 mg per 100 mL). OR Definite development of new bone lesions or soft-tissue plasmacytomas or definite increase in the size of existing bone lesions or soft-tissue plasmacytomas. OR Development of hypercalcemia (corrected serum calcium >11.5 mg per 100 mL) that can be attributed solely to the plasma cell proliferative disorder. |