The combination of t-tau and NFL developed in our previous study (12) (Model 1: y = NFL + 0.15*t-tau; AUC = 0.89) yielded similar sensitivity (75.0%) and specificity (91.2%; AUC = 0.90) for discriminating MSA from PD whereas the combination of FLT3L and NFL (Model 2: y = −1.646 + 0.001*NFL-0.0308*FLT3L) yielded a sensitivity of 81.8% and specificity of 94.8% (AUC = 0.89). Here, FLT3LG is linked to multiple system atrophy.