Relationship of 2-month FLC response to standard M-protein response criteria
| . | FLC responders, no. (%) . | Non-FLC responders, no. (%) . | P . |
|---|---|---|---|
| Association between 2-month FLC response* and 2-month paraprotein† response in patients with abnormal baseline FLC‡ | |||
| All patients | |||
| Paraprotein responders | 29 (91) | 3 (9) | <.001 |
| Nonparaprotein responders | 57 (53) | 50 (47) | |
| Serum and urine | |||
| Paraprotein responders | 13 (93) | 1 (7) | .005 |
| Nonparaprotein responders | 25 (51) | 24 (49) | |
| Serum only | |||
| Paraprotein responders | 10 (91) | 1 (9) | .031 |
| Nonparaprotein responders | 17 (52) | 16 (48) | |
| Urine only | |||
| Paraprotein responders | 6 (86) | 1 (14) | .37 |
| Nonparaprotein responders | 15 (60) | 10 (40) | |
| Association between 2-month FLC response and ECOG overall objective response in patients with abnormal baseline FLC‡ | |||
| All patients | |||
| Overall objective responders | 155 (69) | 69 (31) | <.001 |
| Nonresponders | 28 (30) | 65 (70) | |
| Serum and urine | |||
| Overall objective responders | 99 (68) | 47 (32) | <.001 |
| Nonresponders | 17 (27) | 45 (73) | |
| Serum only | |||
| Overall objective responders | 26 (70) | 11 (30) | .070 |
| Nonresponders | 7 (41) | 10 (59) | |
| Urine only | |||
| Overall objective responders | 30 (73) | 11 (27) | .061 |
| Nonresponders | 4 (29) | 10 (71) | |
| . | FLC responders, no. (%) . | Non-FLC responders, no. (%) . | P . |
|---|---|---|---|
| Association between 2-month FLC response* and 2-month paraprotein† response in patients with abnormal baseline FLC‡ | |||
| All patients | |||
| Paraprotein responders | 29 (91) | 3 (9) | <.001 |
| Nonparaprotein responders | 57 (53) | 50 (47) | |
| Serum and urine | |||
| Paraprotein responders | 13 (93) | 1 (7) | .005 |
| Nonparaprotein responders | 25 (51) | 24 (49) | |
| Serum only | |||
| Paraprotein responders | 10 (91) | 1 (9) | .031 |
| Nonparaprotein responders | 17 (52) | 16 (48) | |
| Urine only | |||
| Paraprotein responders | 6 (86) | 1 (14) | .37 |
| Nonparaprotein responders | 15 (60) | 10 (40) | |
| Association between 2-month FLC response and ECOG overall objective response in patients with abnormal baseline FLC‡ | |||
| All patients | |||
| Overall objective responders | 155 (69) | 69 (31) | <.001 |
| Nonresponders | 28 (30) | 65 (70) | |
| Serum and urine | |||
| Overall objective responders | 99 (68) | 47 (32) | <.001 |
| Nonresponders | 17 (27) | 45 (73) | |
| Serum only | |||
| Overall objective responders | 26 (70) | 11 (30) | .070 |
| Nonresponders | 7 (41) | 10 (59) | |
| Urine only | |||
| Overall objective responders | 30 (73) | 11 (27) | .061 |
| Nonresponders | 4 (29) | 10 (71) | |
An FLC response is defined here as a 50% decrease in the difference between involved and uninvolved FLC levels.
Limited data for serum and urine electrophoresis at 2-month time point reduce sample size to 139 patients.
Abnormal FLC is defined as abnormal ratio and baseline iFLC greater than or equal to 5 mg/dL. Results were similar if all patients included or if abnormal FLC was defined as patients with baseline involved FLC value of greater than or equal to 10 mg/dL (data not shown).