This is a randomized, multicenter trial with stratification done by a single radiologist at the coordinating center (NYU), and patients with comparable disease will be randomized to Sandostatin LAR treatment administered 1 time per month by IM injection for 3 months before (Arm A) or, for non-cured patients, after (Arm B) surgery. All patients will undergo transsphenoidal hypophysectomy. The impact of surgical debulking on responsiveness to Sandostatin LAR will be evaluated.The primary objective of this trial will be to determine whether surgery (debulking of pituitary adenomas) improves the response of patients with acromegaly to treatment with Octreotide LAR, when compared to Octreotide LAR therapy alone.

The current goal of treatment for people with acromegaly is normalization of both growth hormone (GH) and insulin-like-growth-factor-1 (IGF-1) levels. Normalization of GH and IGF-1 levels attenuates the morbidity (hypertension, cardiovascular disease, sleep apnea, increased cancer risk, arthritis) and increased mortality associated with persistent GH and IGF-1 elevation. The optimal approach to achieving these goals in patients with pituitary macroadenomas remains controversial. Available treatment modalities include transsphenoidal hypophysectomy, medical therapy (somatostatin analogues and/or dopaminergic agonists), radiotherapy, or a combination or these interventions. No randomized trials have been conducted to investigate whether surgical debulking of pituitary macroadenomas enhances the efficacy of medical therapy. This study is designed to rigorously investigate whether surgical debulking increases the efficacy of a long-acting depot somatostatin preparation, Sandostatin LAR, so that evidence-based optimal care may be offered to patients with acromegaly.

Inclusion Criteria:

• Carry a diagnosis of de novo acromegaly with an elevated age and sex matched IGF-I and GH >1ng/ml at all time points during OGTT
• Have a pituitary macroadenoma
• Have clinical changes consistent with acromegaly
• Have a single random serum hGH of 12.5 ng/ml or greater
• Both the endocrinologist and surgeon must agree that the patient's health would not be compromised by a three-month period during which time Octreotide LAR is administered.
• Patients currently on dopamine agonist who agree to discontinue medication (2-6 week washout required)

Exclusion Criteria:

• Pregnant or breastfeeding
• Documented loss of vision due to pituitary tumor
• Prior treatment for acromegaly other than dopamine agonists
• Inability to complete the protocol
• Intolerance to octreotide