[Limbic encephalitis: a new paraneoplastic auto-immune manifestation associated with metastatic melanoma?].

BACKGROUND: Several studies indicate an association between immune-related manifestations and prolonged survival in metastatic melanoma. Limbic encephalitis driven by immune-mediated disorders may also be observed during the course of certain cancers. PATIENTS AND METHODS: In November 2009, a 60-year-old woman followed up for metastatic melanoma since July 2005 developed rapidly progressive cognitive disorder. Clinical, biological, MRI and electroencephalogram abnormalities resulted in diagnosis of probably paraneoplastic limbic encephalitis in a context of immune-related manifestations although chemotoxicity could not be ruled out. Auto-immunity with hypothyroidism and thrombocytopenia were seen concomitantly. DISCUSSION: To the best of our knowledge, this is the first reported case of probably paraneoplastic limbic encephalitis associated with melanoma, a new example of an immune-related condition associated with prolonged survival in metastatic melanoma.