The most interesting of scientific discoveries are sometimes hidden in the most obscure of places. In this case an open access journal that I’d never heard of before, and a discussion from the authors that is close but no cigar.
The authors report of a 39-year-old woman who presented with a demyelinating brain lesion, but on further search was found to also have a thymoma (a thyroid cancer). The most interesting finding was that the tumorous cells also contained myelin basic protein that can only be found in the brain (see Figure below).
In my opinion this case is supportive evidence that in some instance demyelinating disease can be a paraneoplastic disorder. Paraneoplastic disorders are remote effects of certain malignancies that affect the nervous system, triggered by an autoimmune response to cancer elsewhere in the body.
Myelin basic protein expression in thymoma after methylprednisolone administration for multiple sclerosis
The relationship between thymic epithelial tumour and demyelinating disease (DD) is unknown and surgical resection has not been optimized. A 39-year-old woman was administrated methylprednisolone for newly diagnosed multiple sclerosis. A thymic tumour was found in the antero-superior mediastinum via computed tomography of the chest. Video-assisted thoracoscopic thymectomy was performed. Histologically, the tumour was diagnosed as Type AB thymoma. Immunohistochemical staining showed positive myelin basic protein (MBP) in the cytosol of spindle cells in the tumour specimen. Germinal centres or lymphocytes infiltration were not noted. Ectopic MBP presentation in thymoma might be correlated with DD.