Challenges in the management of a 7 years old child with thyrotropin-secreting pituitary adenoma and the review of the literature

Introduction: Thyrotropin-producing pituitary adenoma (TSHoma) is a very rare disease, representing less than 1% of the pituitary tumours, present with elevated thyroid hormones and normal/high TSH concentrations. Case Presentation: A 7-year-old boy with nervousness was referred by his psychiatrist for elevated free T4, T3 and TSH levels. Initial evaluation revealed an elevated -subunit.Pituitary MRI demonstrated a macroadenoma. The patient underwent a trans-sphenoidal tumour resection (TSS) which showed positive immunohistochemical staining for TSH, growth hormone, and prolactin in tumoral tissue. Euthyroidism was achieved for one year after TSS, then, recurrence of tumour with elevated TSH and thyroid hormone levels necessitated a re-operation with TSS followed by gamma-knife radiosurgery. The euthyroid state was achieved and lasted for 2.5 years this time, but, due to the recurrence, medical treatment had been commenced with cabergoline and octreotide. Euthyroidism was maintained for the last 4 years on monthly octreotide treatment. A repeat MRI demonstrated no pituitary mass but a mass in the sphenoidal sinus had been detected. Removal of this mass by surgery did not achieve euthyroidism. 68Ga-DOTA-TATE PET/CT showed residual tissue extending from the pituitary region to the sphenoid sinus.The patient's bone age was advanced 2 years at diagnosis which became 4 years in one year after the diagnosis and remained so throughout follow-up, leading to a final height of -3.3 SDS below his target height at the age of 16 years. Conclusion: The diagnosis, treatment, and follow-up of TSHomas are challenging and short stature due to accelerated bone maturation is a complication of paediatric TSHomas.