MMP9 and in situ carcinoma: Within the CIS group at baseline (n = 19), CXCL10, NFL, and MMP-9 in CSF were significantly higher (p ≤ 0.05 in Mann-Whitney U tests) in patients that converted to RRMS during 4 years of follow-up (n = 12) than in non-converters (n = 7), whereas S-NFL (p = 0.10) and the other markers (p = 0.07–0.90) did not differ.