Neurofibromatosis type 2 and multiple sclerosis

•Multiple sclerosis can occur in patients with neurofibromatosis type 2.•Peripheral schwannoma of a patient with both diseases showed a massive t-cell infiltration.•This t-cell infiltration correlated with a very rapid tumor growth. Comorbidity of neurofibromatosis type 2 (NF2) and multiple sclerosis (MS) has rarely been reported. Since immunological mechanisms have been implicated in Nf2, coexistence of the two entities may offer insights into schwannoma pathogenesis with respect to the impact of the immune system. We present the case of a woman with a de novo mutation in the NF2 gene who later developed MS. In addition, we found a significantly higher count of T cells in a laryngeal schwannoma of this patient as compared to a schwannoma removed from a NF2 patient without MS. This finding correlated with a higher growth rate in the case of NF+MS.