Clinical case seminar - Familial intracranial germinoma

Abstract

Background: Intracranial germinomas (ICG) are uncommon brain neoplasms with extremely rare familial occurrence. Because ICG invades the hypothalamus and/or pituitary, endocrine dysfunction is one of the common determinants of these tumours. We present two brothers with a history of ICG. Patient 1 is a 25-year-old male who suffered from weakness of the right half of his body at the age of 18 years. Cranial MRI revealed a mass lesion in the left thalamus. He underwent neurosurgery, and the tumour was removed completely. Histopathological (HP) and immunohistochemical analyses verified the diagnosis of pure germinoma. He experienced complete remission of the tumour after radiation therapy. At the age of 22 years a diagnosis of isolated growth hormone deficiency (IGHD) was established and GH replacement was initiated. Molecular genetic analysis of the tumour tissue detected the mutation within exon 2 in KRAS gene. Patient 2 is a 20-year-old man who presented with diabetes insipidus at the age of 12 years. MRI detected tumour in the third ventricle and pineal region. After endoscopic tumour biopsy the HP diagnosis was pure germinoma. He received chemotherapy followed by radiotherapy and was treated with GH during childhood. At the age of 18 years GH replacement was reintroduced. A six-month follow-up during the subsequent two years in both brothers demonstrated the IGF1 normalisation with no MRI signs of tumour recurrence. Conclusion: To the best of our knowledge, so far only six reports have been published related to familial ICG. The presented two brothers are the first report of familial ICG case outside Japan. They have been treated successfully with GH therapy in adulthood.