PT - JOURNAL ARTICLE AU - Choi, You-Jung AU - Koh, Youngil AU - Lee, Hyun-Jung AU - Hwang, In-Chang AU - Park, Jun-Bean AU - Yoon, Yeonyee E. AU - Kim, Hack-Lyoung AU - Kim, Hyung-Kwan AU - Kim, Yong-Jin AU - Cho, Goo-Yeong AU - Sohn, Dae-Won AU - Paeng, Jin-Chul AU - Lee, Seung-Pyo TI - Independent Prognostic Utility of <sup>11</sup>C-Pittsburgh Compound B PET in Patients with Light-Chain Cardiac Amyloidosis AID - 10.2967/jnumed.121.263033 DP - 2022 Jul 01 TA - Journal of Nuclear Medicine PG - 1064--1069 VI - 63 IP - 7 4099 - http://jnm.snmjournals.org/content/63/7/1064.short 4100 - http://jnm.snmjournals.org/content/63/7/1064.full SO - J Nucl Med2022 Jul 01; 63 AB - 11C-Pittsburgh compound B (PiB) PET/CT visualizes the amount of myocardial amyloid deposit and can be used to prognosticate patients with amyloid light-chain (AL) cardiac amyloidosis (CA). However, whether 11C-PiB PET/CT has any independent additional prognostic value beyond the commonly used biomarkers remains unknown. Methods: This prospective study was on a cohort of 58 consecutive patients with AL CA who underwent 11C-PiB PET/CT. The patients were stratified into 2 groups on the basis of a visual assessment of whether there was myocardial 11C-PiB uptake on PET/CT. The primary endpoint was 1-y overall mortality. The independent prognostic utility of 11C-PiB PET/CT was analyzed using net reclassification improvement and integrated discrimination improvement. Results: Among the 58 patients enrolled, 35 were positive for myocardial 11C-PiB uptake on PET/CT. Patients with myocardial 11C-PiB PET uptake had a worse 1-y overall survival rate than those without (81.8% vs. 45.5%, P = 0.003 by log-rank test). In the multivariate analysis, positivity for myocardial 11C-PiB uptake on PET/CT was an independent predictor of 1-y mortality (adjusted hazard ratio, 3.382; 95% CI, 1.011–11.316; P = 0.048). In analysis of 3 subgroups of patients—those with a troponin I level of at least 0.1 ng/mL, those with an N-terminal pro-B-type natriuretic peptide (NT-proBNP) level of at least 1,800 pg/mL, and those with a difference of at least 180 mg/L between free light chains (the 3 commonly used biomarkers and their thresholds for staging in AL amyloidosis)—Kaplan–Meier curves showed for all 3 subgroups that patients positive for myocardial 11C-PiB uptake on PET/CT had a worse prognosis than those who were negative. Additionally, when the results of 11C-PiB PET/CT were added to these 3 biomarkers, the performance of 1-y mortality prediction significantly improved by net reclassification improvement (troponin I, 0.861; NT-proBNP, 0.914; difference between free light chains, 0.987) and by integrated discrimination improvement (0.200, 0.156, and 0.108, respectively). Conclusion: 11C-PiB PET/CT is a strong independent predictor of 1-y overall mortality and provides incremental prognostic benefits beyond the 3 commonly used biomarkers of AL amyloidosis staging. Considering the recent development of numerous amyloid-targeting molecular imaging agents, further investigations are warranted on whether PET/CT should be included in risk stratification for patients with AL CA.