ESPE Abstracts

Introduction: Brain magnetic resonance imaging (MRI) is routinely performed to identify brain lesions in boys with central precocious puberty (CPP). In contrast to girls, in whom more than 90% of cases are idiopathic, it has been reported that 4 up to 75% of boys with CPP have pathological brain lesions.

Aim: to evaluate the prevalence of brain lesions in males with isolated CPP and to identify potential clinical and biochemical predictors of brain abnormalities.

Methods and Results: We conducted a retrospective cross-sectional study by retrieving clinical records of boys diagnosed with CPP from 2000 to 2022 diagnosed in a single tertiary center. Sixty-eight boys with CPP diagnosis were identified. All boys underwent a thorough endocrine assessment and brain MRI scan with a detailed examination of the hypothalamic-pituitary area. Patients with already known CNS abnormalities, associated endocrine disorders, previous hormonal therapies, malformations, neurofibromatosis, or other inherited conditions were excluded. The study population was subdivided into 3 groups according to the age at onset of pubertal signs: 48 patients with age > 8 years, 17 patients with age between 6-8 years, 3 patients with age< 6 years. The MRI findings were categorized into 3 groups: group 1, normal, boys with no CNS abnormalities or minor intracranial alterations not involving the hypothalamic pituitary region; group 2, mild abnormalities of the hypothalamic-pituitary region, considered incidental findings unrelated to central precocious puberty; and group 3, pathological and CNS abnormalities associated with precocious puberty. Brain MRI showed no alteration in 50 patients (73.7%), incidental findings of hypothalamic-pituitary area or other brain areas unrelated to CPP was found in 13 cases (19%), and pathological brain lesions were observed in 5 boys (7.3%). In group 3, 3 patients had tuber cinereum hamartoma (age 6-8 years) and 2 patients low-grade diencephalic ganglioneuroma (age older than > 8 years). Boys with normal MRI (aged 8.28 ± 1.52 years) were older than boys with pathological MRI (aged 7.66 ± 0.82 years, P=0.08). No significant differences in basal LH, LH peak after GnRH test, or testosterone level between MRI-groups were observed. Furthermore, no brain lesions in 7 adopted-boys was found and no history of precocious puberty was reported in boys with pathological-MRI group versus normal-MRI group (18 cases, 39%).

Conclusions: Our findings indicate that the prevalence of pathological brain lesions in boys with CPP, when accurately stratified, is considerably lower than previously reported thus making the diagnosis less alarming.