Endocrine Abstracts

A 4.9-year-old girl presented with symptoms suggestive of early puberty and rapid growth. Her medical history revealed that she had been a tall child since infancy. Family history was notable for Lynch syndrome in her father and paternal grandmother. Upon examination, the patient was pre-pubertal but had a height of 124 cm (SDS 3.5) and a height velocity of 15 cm/year. Further investigations revealed elevated levels of IGF-1, IGFBP3, and failed GH suppression on an OGTT, indicating a potential somatotropinoma. Imaging with contrast MRI confirmed the presence of a pituitary microadenoma, leading to referral to paediatric neurosurgery and geneticist. At the age of 5.66 years, the patient underwent a trans-sphenoidal excision of the microadenoma with intra-operative MRI guidance. Histology confirmed the presence of a neuroendocrine tumor expressing growth hormone. Post-surgery, her height velocity and IGF-1 levels decreased, indicating a positive response. However, subsequent monitoring revealed a rise in IGF-1 levels, suggesting incomplete resection or recurrence. Repeat imaging with contrast MRI and 11C-Methionine PET scan confirmed the presence of a small residual adenoma in the pituitary gland. In light of this, the patient has been initiated on Pegvisomant therapy, which has resulted in rapid decline in IGF-1 levels. A repeat MRI scan is planned to determine the need for further surgery. Genetic testing using the R217 gene panel has shown normal results, but the results of X-linked acro-gigantism genetic testing are still pending. The family has expressed reluctance for the patient to undergo genetic testing for Lynch syndrome, although the association of corticotroph and prolactin-secreting adenomas with Lynch syndrome has been noted. Discussions regarding the importance of genetic testing for Lynch syndrome are ongoing with the family. Currently, the family faces a decision between long-term Pegvisomant therapy, provided the tumor remains under control, or pursuing repeat surgery, which carries a high risk of subsequent pituitary hormone deficiencies. The case highlights the challenges encountered in managing children with somatotropinomas, emphasizing the importance of multidisciplinary care and close monitoring to optimize treatment outcomes. The collaborative efforts of paediatric endocrinologists, neurosurgeons, and geneticists are crucial in ensuring appropriate diagnosis, treatment, and follow-up care.