Heart failure & cardiomyopathiesDiagnostic or prognostic study
Diagnostic Performance of the New Free Light Chain Ratio in Systemic Amyloidosis
- Diagnostic accuracy study
Authors' conclusion
The new FLCR demonstrates equivalent diagnostic sensitivity in AL amyloidosis and can be integrated into complete response criteria. In patients with suspected ATTRwt amyloidosis, it significantly reduces the proportion of FLCR-only abnormalities, thereby limiting the need for biopsy confirmation.
Study context
- Population
- Patients with AL amyloidosis and ATTRwt amyloidosis1,705 AL
- Comparison
- New free light chain ratio (FLCR) vs conventional FLCR
- Outcome
- Diagnostic performance (sensitivity for monoclonal component detection)
Performance
As reported in the abstract
Diagnostic sensitivity in AL amyloidosis with negative serum and urine IFE (n = 44) · at diagnosis
| Test or model | Normal FLCR | Sensitivity | Overall sensitivity for MC detection |
|---|---|---|---|
| New FLCR | 15 | 65.9% (95% CI: 50.0%-79.5%) | 99.2% |
| Conventional FLCR | 13 | 70.4% (95% CI: 55.8%-82.5%) | 99.1% |
- New FLCR vs Conventional FLCR: P = 0.82 — no significant difference
Further findings
Abnormal FLCR in ATTRwt with negative serum and urine IFE
Concordance in complete response definition, AL amyloidosis · hematologic response assessment
- Concordance between the 2 FLCR methods
- 94.9% (95% CI: 93.4%-95.9%)
Original publication
Diagnostic Performance of the New Free Light Chain Ratio in Systemic Amyloidosis. JACC CardioOncol. Published 11 September 2025. doi:10.1016/j.jaccao.2025.07.012
Summarised from the published abstract; every number is checked against it