title: Pituitary and systemic autoimmunity in a case of intrasellar germinoma.
abstract: Germinomas arising in the sella turcica are difficult to differentiate from autoimmune hypophysitis because of similar clinical and pathological features. This differentiation, nevertheless, is critical for patient care due to different treatments of the two diseases. We report the case of an 11-year-old girl who presented with diabetes insipidus and growth retardation, and was found to have an intra- and supra-sellar mass. Initial examination of the pituitary biopsy showed diffuse lymphocytic infiltration of the adenohypophysis and absent placental alkaline phosphatase expression, leading to a diagnosis of hypophysitis and glucocorticoid treatment. Because of the lack of clinical and radiological response, the pituitary specimen was re-examined, revealing this time the presence of scattered c-kit and Oct4 positive germinoma cells. The revised diagnosis prompted the initiation of radiotherapy, which induced disappearance of the pituitary mass. Immunological studies showed that the patient's serum recognized antigens expressed by the patient's own germinoma cells, as well as pituitary antigens like growth hormone and systemic antigens like the Sjögren syndrome antigen B and alpha-enolase. The study first reports the presence of pituitary and systemic antibodies in a patient with intrasellar germinoma, and reminds us that diffuse lymphocytic infiltration of the pituitary gland and pituitary antibodies does not always indicate a diagnosis of autoimmune hypophysitis.
authors.affiliation: Department for Neurosurgery, Georg August University Göttingen, Göttingen, Germany.
authors.forename: Angelika
authors.initials: A
authors.lastname: Gutenberg
authors.forename: Jennifer J
authors.initials: JJ
authors.lastname: Bell
authors.forename: Isabella
authors.initials: I
authors.lastname: Lupi
authors.forename: Shey-Cherng
authors.initials: SC
authors.lastname: Tzou
authors.forename: Melissa A
authors.initials: MA
authors.lastname: Landek-Salgado
authors.forename: Hiroaki
authors.initials: H
authors.lastname: Kimura
authors.forename: Jack
authors.initials: J
authors.lastname: Su
authors.forename: Lefkothea P
authors.initials: LP
authors.lastname: Karaviti
authors.forename: Roberto
authors.initials: R
authors.lastname: Salvatori
authors.forename: Patrizio
authors.initials: P
authors.lastname: Caturegli
mesh_terms: D020274:Autoimmune Diseases of the Nervous System / Q000150:complications / Q000175:diagnosis* / Q000276:immunology / Q000473:pathology; D015551:Autoimmunity / Q000502:physiology; D002648:Child; D020790:Diabetes Insipidus, Neurogenic / Q000150:complications / Q000473:pathology; D003937:Diagnosis, Differential; D004660:Encephalitis / Q000150:complications / Q000175:diagnosis / Q000473:pathology; D005260:Female; D018237:Germinoma / Q000150:complications / Q000175:diagnosis* / Q000276:immunology / Q000473:pathology; D006801:Humans; D010900:Pituitary Diseases / Q000150:complications / Q000175:diagnosis* / Q000276:immunology / Q000473:pathology; D010902:Pituitary Gland / Q000276:immunology / Q000473:pathology; D010911:Pituitary Neoplasms / Q000150:complications / Q000175:diagnosis* / Q000276:immunology / Q000473:pathology; D012658:Sella Turcica / Q000473:pathology