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

Abstract

To investigate whether 3 months' preoperative treatment with lanreotide improved outcome in newly diagnosed patients with acromegaly resulting from invasive pituitary macroadenoma. After baseline evaluation, untreated patients were randomized to undergo direct transsphenoidal 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. 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). 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.