LAUSR

BACKGROUND Endocrine deficiencies, including hypothalamic-pituitary-gonadal axis (HPGA) impairment, are common in survivors of childhood and adolescent medulloblastoma. Still, data regarding pubertal development and fecundity are limited, and few studies assessed HPGA function in males. We aimed to describe HPGA function in a large cohort of patients with medulloblastoma. METHODS A retrospective study comprising all 62 medulloblastoma patients treated in our center between 1987-2021, who were at least two years from completion of therapy. HPGA function was assessed based on clinical data, biochemical markers, and questionnaires. RESULTS Overall, 76% of female patients had clinical or biochemical evidence of HPGA dysfunction. Biochemical evidence of diminished ovarian reserve was seen in all prepubertal girls (n=4). Among the males, 34% had clinical or biochemical evidence of gonadal dysfunction, 34% had normal function, and 29% were age-appropriately clinically and biochemically pre-pubertal. The difference between males and females was significant (p=0.003). Cyclophosphamide-equivalent dose (CED) was significantly associated with HPGA function in females, but not in males. There was no association between HPGA dysfunction and other endocrine deficiencies, length of follow up, weight status, and radiation treatment protocol. Two female and two male patients achieved successful pregnancies, resulting in 6 live births. CONCLUSIONS HPGA dysfunction is common after treatment for childhood medulloblastoma. This is seen more in females, likely due to damage to the ovaries from spinal radiotherapy. Our findings may assist in counselling patients and their families regarding risk to future fertility and need for fertility preservation.