Table 2.

Updated Hematologic and Organ Response Criteria

Response Type	Abbreviation	Criteria
Hematologic response
Complete response	CR	Negative serum and urine IFE normal κ/λ ratio
Very good partial response	VGPR	dFLC < 40 mg/L*
Partial response	PR	dFLC decrease ≥ 50%
No response	NR	Other
Organ response†
Heart		Mean interventricular septal thickness decreased by 2 mm, 20% improvement in ejection fraction, improvement by two New York Heart Association classes without an increase in diuretic use, and no increase in wall thickness and/or a reduction (≥ 30% and ≥ 300 ng/L) of NT-proBNP in patients in whom the eGFR is ≥ 45 mL/min/1.73 m2
Kidney		50% decrease in 24-hour urinary protein excretion in the absence of a reduction in eGFR ≥ 25% or an increase in serum creatinine ≥ 0.5 mg/dL
Liver		50% decrease in abnormal alkaline phosphatase value
		Decrease in liver size radiographically at least 2 cm

Abbreviations: IFE, immunofixation electrophoresis; dFLC, difference in concentration between involved and uninvolved free light chains; NT-pro BNP, N-terminal pro-brain natriuretic peptide; eGFR, estimated glomerular filtration rate.

^*If a patient with AL amyloidosis caused by monoclonal λ light chain has a serum concentration of λ 254 mg/L and κ 24 mg/L, the dFLC is 230 mg/L.

^†Reliable, widely available methods for defining peripheral and autonomic nervous system response were felt not to exist.⁴⁸