intracranial germ cell tumors ( gcts ) are rare neoplasms that typically arise in the pineal and suprasellar regions .
they account for 0.5 - 3% of all pediatric tumors of the central nervous system ( cns ) , germinomas being the most common histological type .
although the production of tumor - associated human chorionic gonadotropin ( hcg ) by a germinoma is a rare occurrence , it may lead to precocious puberty ( pp ) due to it 's structural and functional similarity to luteinizing hormone ( lh ) .
we report a case of hcg - producing tumor located in the suprasellar region and associated with sexual precocity .
a 10-year - old male patient was brought to our department with premature pubarche and onset of facial acne at the age of 8 years and increase in penis size at the age of 9 years .
concomitantly , he had a progressive , gradually worsening holocranial headache associated with drowsiness and loss of appetite .
previously , he was a healthy patient , born by spontaneous vaginal delivery at term weighing 3510 g and measuring 50 cm .
the patient had no family history of endocrine disorders , sexual precocity , or consanguinity .
the mother 's and father 's self - reported height was 155 cm and 175 cm respectively .
physical examination revealed height of 148 cm ( 90 - 95 percentile ) , weight of 39 kg ( 75 - 90 percentile ) , blood pressure of 90/60 mmhg , heart rate of 60 beats per minute , facial acne , abdominal fat deposition in the periumbilical region , bilateral , symmetrical and prepubertal sized ( 3 ml ) testes within the scrotum , 8-cm long penis , and tanner stage p3-g2 .
magnetic resonance imaging ( mri ) of the brain showed a large , hyperintense tumor in the suprasellar region , with hypodense areas inside the tumor , which was located in the anterior third ventricle , measuring 3 cm in the largest diameter and causing triventricular dilatation [ figure 1 ] .
radiographs of the hands and wrists revealed significant acceleration of bone age ( ba ) in relation to chronological age ( ca ) ( ba : 13 years ; ca : 10 years and 8 months ; standard deviation : 10 months ) . mri of the abdomen yielded normal results .
laboratory tests revealed that the values for serum glucose , albumin , calcium , sodium , potassium , renal function , and liver function were within the normal limits .
hormonal tests showed increased hcg levels in both blood and cerebrospinal fluid ( csf ) , increased total testosterone levels , and hypopituitarism ( unresponsiveness to gonadorelin stimulation test ) [ table 1 ] .
large , hyperintense suprasellar tumor , with hypodense areas inside , located in the anterior third ventricle , measuring 3 cm in the largest diameter ( arrows ) and causing triventricular dilatation results from hormonal tests and tumor marker tests the patient was diagnosed with an hcg- and testosterone - producing tumor associated with hypopituitarism and intracranial hypertension .
hormone replacement therapy was initiated with levothyroxine and hydrocortisone , and transcranial surgery was performed .
the patient showed complete regression of sexual characteristics and acne , with normal laboratory tests post - operatively .
uniform large tumor cells with large nuclei , prominent nucleoli , and abundant glycogen - rich cytoplasm are noted among reactive inflammatory cells and bands of connective tissue , supporting the diagnosis of germinoma
pp is defined as the presence of signs of puberty before the age of 8 years in girls and 9 years in boys .
pp is more frequently found in girls , with a female - to - male ratio of 12.3:1 .
it is important that pp be properly investigated in boys because , unlike girls , the onset of idiopathic pp is uncommon among boys , having an organic cause in most cases .
gonadotropin - independent pp ( gipp ) results from an increased secretion of sex hormones , regardless of the maturation of the hypothalamic  pituitary  gonadal axis .
hcg - producing tumors , including gonadal and extragonadal gcts may lead to gipp . in the present case , which reported premature pubarche , increased penis size and small testicular size compared to the overall pubertal development , high testosterone levels associated with suppressed lh and follicle - stimulating hormone ( fsh ) levels and an unresponsiveness to a gnrh analog - stimulation test confirmed the diagnosis of gipp .
gcts account for 3 - 11% of all childhood tumors in the united states and western europe , whereas in japan they account for 12.5 - 16% of the cases . among the gcts ,
extragonadal gcts often occur in the pineal and suprasellar regions , as in the case described here .
the clinical presentation of suprasellar gcts may include panhypopituitarism , diabetes insipidus , and visual disturbances , with a long pre - diagnosis period , generally longer than 1 year . in the present case
, the effects of tumor compression led to hypopituitarism and manifestations of intracranial hypertension , such as headache and papilledema .
data from the literature have demonstrated the presence of hcg and its subunits in tumor cells of different origins , including cns neoplasms . according to reports on hcg - producing germinomas , including a japanese series of 111 cases of intracranial gcts , these tumors account for 18% of all germinomas .
it is known that these lesions have a worse prognosis compared to non - secretory germinomas , with a higher recurrence rate and shorter survival . however , detection of hcg is not a marker of metastasis or tumor size , and its presence often indicates the activity of syncytiotrophoblastic elements within the tumor .
both serum and csf hcg measurements in our patient were well above the normal limits , a finding that , together with the mri scans , is consistent with the diagnosis of an hcg - producing tumor , which after biopsy was classified as a germinoma .
increased stature , advanced ba , presence of pubic hair and acne , and early genital development were caused by the increase in serum testosterone levels .
hcg is structurally similar to lh , and excessive increases may stimulate the leydig cells of the testes to produce testosterone . as a result , the patient also showed pituitary - axis suppression , with reduced levels of gonadotropic hormones .
reduced fsh levels may explain the lack of correlation between testicular growth and other sexual characteristics presented by the patient , since testicular maturation depends upon this hormone .
characteristics on computed tomography or mri images often do not provide sufficient information for a histological diagnosis .
therefore , given the diversity of the tumor subtypes found in the suprasellar region , obtaining adequate biopsy specimens is of paramount importance .
for this purpose , open surgery is preferable , as performed in this case , and the histological examination should define the approach that will be used .
 this study aims to report a rare case of precocious puberty ( pp ) due to a human chorionic gonadotropin ( hcg)-producing germinoma located in the suprasellar region . a 10-year - old male patient presented with sexual precocity , headache , drowsiness , loss of appetite , and papilledema . 
 significant acceleration of bone age in relation to chronological age , high serum total testosterone levels , and hypopituitarism ( unresponsiveness to stimulation test ) were observed . magnetic resonance imaging ( mri ) of the brain showed a large suprasellar tumor and triventricular dilatation . 
 high hcg levels were found in both blood and cerebrospinal fluid . 
 hormone replacement therapy and transcranial surgery associated with radiotherapy were performed , with complete regression of sexual characteristics and normal laboratory tests post - operatively . 
 clinical and laboratory findings , in addition to mri scans , led to the diagnosis of an hcg - producing tumor and pp , which represents a rare report in the literature . 
Introduction
Case Report
Discussion