Endocrine Abstracts

Acromegaly prevalence is 2.8–13.7 cases per 100,000. Diagnosis at the early stages can be quite challenging and management is complex involving various specialties to achieve remission of the condition. September 2013, 49 year old lady presented to optometry with few months of bumping into things. She was later found to have superior bitemporal hemianopia. She later described having to change her wedding rings multiple times over the past year with increase in size of shoes. 3 months after presentation, January 2014, diagnosis of acromegaly was made with IGF-1 level of 90.7 nmol/l (4–29 nmol/l) and nadir growth hormone level of 19.3 pg/l. Urgent MRI visualised 2.5*2.4 cm pituitary adenoma with suprasellar extension. A month later she underwent transphenoidal debulking. Histology stained very strongly for growth hormone. Post operative scan showed good tumour bulk reduction and two areas of residual tissue, one posteriorly and the other close to the cavernous sinus. Post-surgically bilateral hemianopia showed marked improvement. Patient was started on 60 mg Lanreotide. After a month due to lack of response this was increased to 90 mg. Medication was eventually stopped after 3 months due to nausea, abdominal discomfort, diarrhoea and later on muscle twitches. Methionine-PET scan showed clear focus within the pituitary that was likely to be the source of ongoing excess growth hormone production. Second debulking operation was done April 2016. IGF-1 stayed constant between July and Septemper of 2016 at 105.4 nmol/l. Patient underwent 5 week radiotherapy early 2017. Lanreotide was re-trialled and stopped due to itching and twitching. Cabergoline was used next and echocardiography follow up showed no evidence of valvular dysfunction. Cabergoline dose was increased and she had side effects which led to it being stopped (nausea drowsiness 24 hours after each dose). Patient was commenced on Pegvisomant and IGF-1 levels fell from 94 to 35 nmol/l; currently on an increased dose of Pegvisomant from 10 to 15 mg SC due to slight increase of IGF-1 levels from 35 to 43 nmol/l.

Conclusion: Management of acromegaly is complex and requires extensive input from both surgical and medical specialties. Debulking is successful in 74% of patients with macroadenoma. Medical therapies can include Somatostatin analogues, cabergoline, octreotide and at last resort pegvisomant. Multidisciplinary approach is essential for remission of the condition with long term monitoring for co-morbidities, notably cardiovascular outcomes.