Endocrine Abstracts

Introduction: Pituitary gigantism is a rare but clinically significant paediatric condition. Transphenoidal surgery is the treatment of choice, however medical treatment is often considered as adjuvant therapy.

Case report: A 10.6 year old boy presented with tall stature. With hindsight he was noticeably tall from age 5 years. At 10 years his height velocity was 12 cm/year, prompting referral and further investigation. His height was 178.7 cm (+5.79 sds above mean), and well outside the family target centile range. IGF-1 was elevated at 78.6 nmol/L (10.6-60.8 nmol/l) and an OGTT demonstrated non-suppression of GH (trough value 5.5 mcg/L, normal =<0.5). His bone age was 11.03 years. The remaining pituitary profile and visual fields were normal. Initial contrast MRI was inconclusive but C11 methionine PET/CT at Addenbrooke’s identified a pituitary microadenoma as a potential surgical target. Genetics for AIP, MEN, MEN4 were negative, while results for Carney complex are pending. He has been recruited into an on-going national research project. An MDT clinic held with the patient, his parents, paediatric and adult endocrinologists, neuroradiology and neurosurgical teams allowed discussion about medical and surgical treatment options.In view of his young age, his prepubertal status, a wish to allow him to settle into his new high school, and his desire to reach a final height taller than his father’s own height, it was decided to try medical therapy first with octreotide, a somatostatin analogue. In addition, pubertal induction was commenced and bilateral epiphysiodesis surgery performed. While the initial response to octreotide was positive (IGF-1 43.2 nmol/L, average GH on profiling=2.0 mcg/L, aiming for <2.5), four months into therapy it was noted that the IGF-1 was climbing (57.8 nmol/L) and a repeat GH profile was not fully suppressed (average GH 2.8 mcg/L). In view of this the patient proceeded to have successful transphenoidal surgical de-bulking of the adenoma.

Conclusion: Rare cases such as this require the sharing of knowledge, experience and expertise so the best possible care is offered. It is often necessary to work across sites and disciplines. Each case requires an individual approach tailored to the patient and their family.