Endocrine Abstracts

A 28-year-old female presented with oligomenorrhoea and bilateral headaches in 2018. Initial blood testing revealed raised prolactin, prompting further assessment of pituitary function. This showed a high IGF-1(132 nmol/l), subsequent oral glucose tolerance test confirmed the diagnosis of acromegaly. It is worth noting that she did not exhibit many of the typical clinical features of acromegaly. MRI demonstrated a left-sided pituitary macroadenoma invading the cavernous sinus. She had normal visual fields. Transsphenoidal surgery was undertaken; histopathology showed a somatotroph adenoma, MIB-1 5% and raised mitotic activity – a higher risk subtype. Post-operative IGF-1 remained elevated (85-95 nmol/l) and the MRI showed residual disease. She was commenced on 4-weekly Lanreotide 120 mg injections, which partially improved headaches. IGF-1 remained elevated despite Lanreotide. Cabergoline 0.25 mg once weekly was added and uptitrated to 1 mg twice weekly. Further treatment at this point was delayed as the patient wished to have a family. Genetic testing undertaken for MEN-1 and AIP were negative. Our patient subsequently became pregnant. Cabergoline was discontinued and Lanreotide was reduced to 4-weekly intervals. She required Metformin in pregnancy for Gestational Diabetes Mellitus (GDM). Lanreotide was discontinued at 24-weeks given patient wanted to breastfeed post-partum. Visual fields were monitored each trimester. Post-partum, elevated IGF-1 levels persisted (61.9 nmol/l), headaches returned, visual fields worsened, prompting recommencement of Lanreotide. Subsequent MRI pituitary showed stable appearances. At 14-months post-partum, our patient became pregnant again. Lanreotide injections were paused at 9-weeks pregnant. She developed GDM (diet-controlled), pregnancy-induced hypertension and obstetric cholestasis. Post-partum IGF-1 levels remained elevated (83.7 nmol/l), prompting recommencement of Lanreotide. Headaches worsened and subsequent MRI showed stable radiological disease. IGF-1 levels fell but remained above range. Despite multiple interventions, the persistence of residual disease and ongoing symptoms led to an MDT recommendation for radiotherapy. The decision was influenced by the ineffectiveness of cure with further surgery and the completion of the patient’s family. While awaiting radiotherapy Pegivisomant is being commenced, aiming to better control Growth Hormone levels and alleviate ongoing symptoms. This case demonstrates the importance of keeping an open mind when considering atypical clinical presentations of acromegaly, the escalation of treatment and management plans in acromegaly. We are also reminded of the importance of tailoring surgical management to the young female patient whose priority is fertility preservation and the use of somatostatin analogues in pregnancy. Finally, the case highlights the importance of the endocrinologist’s role of remembering to undertake genetic testing in appropriate patients.