Endocrine Abstracts

JOINT2070

Intracranial germ cell tumors (ICGCTs) in children are one of the factors leading to peripheral precocious puberty. Beta-human chorionic gonadotropin (β-HCG) exhibits luteinizing hormone (LH)-like functions. Intracranial germ cell tumors secrete β-HCG, which binds to LH receptors in the testes, triggering gonadotropin-releasing hormone (GnRH)-independent testosterone secretion, thereby causing precocious puberty. However, ovarian activation in females requires the simultaneous action of LH and follicle-stimulating hormone (FSH), and β-HCG has a low FSH-like activity, meaning that peripheral precocious puberty caused by intracranial germ cell tumors is more commonly seen in males. Female cases are rare. This clinical study summarizes the clinical features and pathogenesis of three cases of β-HCG-secreting non-gonadal germ cell tumors of the brain, presenting as peripheral precocious puberty and central diabetes insipidus. One case progressed to rapidly advancing central precocious puberty. The three patients all presented with central diabetes insipidus and peripheral precocious puberty, with two cases also complicating central adrenal insufficiency and central hypothyroidism. The β-HCG levels in peripheral blood were 5010 mIU/ml, 314. 3 mIU/ml, and 202. 8 mIU/ml, respectively. After treatment with radiotherapy and chemotherapy, β-HCG levels normalized, and the Tanner stage regressed to stage I. One case progressed to rapidly advancing central precocious puberty. Analysis suggests that this is related to prolactin (PRL), tumor-derived aromatase, and FSH-like function. Therefore, for female patients with precocious puberty, regular testing for β-HCG and alpha-fetoprotein (AFP) is necessary, especially for those with central nervous system symptoms. A thorough evaluation with pituitary region MRI (plain and contrast-enhanced) is crucial to exclude organic diseases such as tumors. Furthermore, in younger female patients with precocious puberty, vigilance for organic lesions should not be relaxed.