(3) We identified higher levels of proinflammatory cytokines, particularly IL-2 (median [IQR], RR-MS = 0.2 [0–0.7]; P-MS = 0.1 [0–1.6]; IC = 0.1 [0.0–0.1]; p < 0.005), IL-6 (RR-MS = 0.9 [0.3–2.3]; P-MS = 0.8 [0.1–2.7]; IC = 0.1 [0.0–0.5]; p < 0.005), IL-12 (RR-MS = 0.5 [0–1.1]; P-MS = 0.5 [0–1.1]; IC = 0.0 [0.0–0.3]; p < 0.005), and GM-CSF (RR-MS = 15.6 [4.8–26.4]; P-MS = 14 [3.3–29.7]; IC = 8.9 [4.7–11.7]; p < 0.005) in MS patients compared with IC. Here, IL6 is linked to myeloid sarcoma.