Table 3.

Recovery of serum κ free light chains (FLC) on sample dilution by two methods.

Sample ID	IMMAGE κFLC concentration (mg/L) after multiplication at final sample dilution							BNII κFLC concentration (mg/L) after multiplication at final sample dilution
	1 in10 a	1 in 50	1 in 100	1 in 200	1 in 400	1 in 1000	1 in 2000	1 in 100 b	1 in 400	1in 2000	1 in 8000
1) IIMM c	127	384	384					100	183
2) LCMM c	185	352	437					162	238
3) IIMM c	124	292	315					88	138
4) IIMM	>198			574	428			>179	387
5) IIMM	>198			798	768			>179		642
6) IIMM	>198					4050	3440	>179			3320
7) IIMM	>162	218		206				114	164	196
8) IIMM d Nonlinear	>198	>990		2500		2520		133		826
9) No clinical notes available Antigen excess e	75						20,300 (1 in 5000)	N/a

^aIMMAGE κFLC measuring range for initial sample dilution of 1 in 10 was 6.6–198 mg/L (Freelite^™ Lot 232704B) and 5.4–162 mg/L (Lot 241673D);

^bBNII κFLC measuring range for initial sample dilution of 1 in 100 was 5.6–179 mg/L (Lot 239854C);

^cSamples 1, 2 and 3 gave ~3-fold higher values by IMMAGE and ~2-fold by BNII on further sample dilution; initial FLC concentrations are within the measuring range;

^dSample 8 was nonlinear by BNII and concentration was ~6-fold higher at 1 in 2000 final sample dilution compared with initial 1 in 100 dilution;

^eSample 9 was underestimated at initial 1 in 10 IMMAGE dilution due to antigen excess; values were 20,300 mg/L and 17,500 mg/L at 1 in 5,000 and 1 in 10,000 final sample dilutions, respectively.

N/a, not available; IIMM, intact immunoglobulin myeloma; LCMM, light chain myeloma.