Preoperative Lanreotide Treatment Improves Outcome in Patients with Acromegaly Resulting from Invasive Pituitary Macroadenoma

Abstract

OBJECTIVE: To investigate whether 3 months' preoperative treatment with lanreotide improved outcome in newly diagnosed patients with acromegaly resulting from invasive pituitary macroadenoma. METHODS: After baseline evaluation, untreated patients were randomized to undergo direct trans-sphenoidal surgery or lanreotide treatment (30 mg via intramuscular injection every 2 weeks, increased to 30 mg/week at week 8 if growth hormone nadir > 2.5 μg/l), for 3 months prior to surgery. Tumour shrinkage following lanreotide treatment was analysed. Cure was evaluated at 3 months postsurgery by measuring growth hormone and insulinlike growth factor-1 (IGF-1) levels. RESULTS: Preoperative lanreotide treatment significantly reduced mean tumour size. Growth hormone and IGF-1 levels were lower in the pretreatment group than in the direct surgery group at 3 months postsurgery. According to combined growth hormone and IGF-1 levels, significantly more patients were cured by trans-sphenoidal surgery in the pretreatment group compared with the direct surgery group (11 of 24 and five of 25 patients, respectively). CONCLUSIONS: Lanreotide treatment for 3 months before trans-sphenoidal surgery effectively reduced tumour size, and improved surgical cure rate, in newly diagnosed patients with acromegaly resulting from invasive pituitary macroadenoma.