Neuroendocrine tumour metastatic brain disease during immunosuppressive treatment for paraneoplastic GABAB receptor antibodies encephalitis: Is immunosuppression always beneficial?

BACKGROUND

Limbic autoimmune encephalitis (LE) should be considered in any patient with acute or subacute neuropsychiatric manifestations, without other common causes of encephalitis. Y-Aminobutyric-acid-B-receptor (anti-GABABR) antibodies are rarely encountered in association with LE.

METHODS

A 74-year-old patient presented with a progressive cognitive degradation and generalized tonic-clonic seizures, with positive anti-GABABR. He declined under immunosuppression treatment. Control magnetic resonance revealed brain lesions, which became positive for pulmonary neuroendocrine tumour metastatic disease.

CONCLUSIONS

The occurrence of diversified neurological manifestations of an underling tumour is difficult to manage. We speculate if in some cases, immunosuppression can itself facilitate tumour progression.