TNFSF14 and in situ carcinoma: In the same scenario of a patient fulfilling the clinical and neuroradiological criteria for a CIS with dissemination in space but without dissemination in time, an OCB+ result would be sufficient, regardless of the KI result.6Future studies applying both methods in parallel, in populations with known clinical and radiological data, might definitively establish the sensitivity and specificity of measuring IgG light chains for the diagnosis of MS.