Participants agreed that quantification of blood-based NfL is very effective in determining MS activity (mean ± SD: 4.5 ± 0.5), inflammation-associated neurodegeneration (mean ± SD: 4.3 ± 0.5) and in determining response to treatment (mean ± SD: 4.8 ± 0.4). The gene discussed is NEFL; the disease is myeloid sarcoma.