Endocrine Abstracts

Background: Acromegaly is a rare condition characterised primarily by tumourous production of excess Growth Hormone (GH) from a pituitary adenoma. Clinical management aims at normalising serum IGF1 levels within sex and age-adjusted reference parameters. Treatment options include pituitary surgery, medical therapy with somatostatin analogue (SSA), cabergoline, pegvisomant or radiotherapy. A combination of treatment modalities is common for the majority of patients.

Aims: We retrospectively reviewed the long-term clinical outcomes in our large cohort of patients with acromegaly at the Royal Victoria Infirmary.

Methods: All patients with acromegaly seen in our dedicated weekly pituitary clinic or discussed in our pituitary MDT since 2019 were included. Data extracted: patient demographics, biochemical and radiological findings at diagnosis, treatment modalities, latest IGF1 level during follow-up and duration of follow-up. IGF1 expressed as x sex-and-age-adjusted upper limit of normal. Data expressed as mean, S.D. and percentages.

Results: From 1970 to 2021, 111 patients were diagnosed with acromegaly. F: M is 1:1, with a mean age of 48 (±16) years and IGF1 level 2.9×ULN (±1.1) at diagnosis. 85% of patients had a pituitary macroadenoma. The mean duration of follow-up is 13 (±11.6) years. 75% of patients underwent pituitary surgery, and 24% were treated with medical therapy only. One patient is awaiting surgery. Overall 87/110 (79%) achieved an IGF1 ≤1.3×ULN at the latest review. Post-pituitary surgery, 14% of patients achieved normal IGF1 levels, but 23% of patients achieved IGF1 ≤1.3×ULN. Further treatment modalities to achieve IGF1 ≤1.3×ULN in the surgical cohort included: cabergoline (10%), SSA (32%), a combination of SSA and cabergoline (8%), pegvisomant (4%) and radiotherapy (7%). Overall, satisfactory IGF1 control (≤1.3×ULN) was achieved in 50% of patients on SSA, 26% on cabergoline and 18% after radiotherapy.

Conclusions: The remission rate post-surgery in our cohort of patients with acromegaly, primarily secondary to macroadenomas, is low at 14%. Nevertheless, either alone or in combination, long-term medical treatment modalities achieved adequate control in 79% of patients.