The treatment with SA still leaves some questions unanswered. Firstly, SA treatment often results in a concomitant suppression of the insulin secretion, which might lead to clinically significant glucose intolerance. Secondly, the traditional evaluation of disease activity by measuring circulating levels of GH and total IGF-I is not reliable enough

Hypotheses: Treatment of acromegaly with SA versus surgery alone is associated with:

• Glucose intolerance despite normalized insulin sensitivity
• Modified peripheral GH activity in peripheral target organs assessed on molecular endpoints

Acromegaly is a rare disease usually caused by a benign growth hormone (GH) producing pituitary adenoma. In case of inadequate disease control, the condition is associated with significant morbidity and approximately a doubling of mortality compared to the background population. Medical treatment with somatostatin analogues (SA) has been employed for about 20 years and is a well-established treatment in cases where surgery is impossible or inadequate. The treatment with SA still leaves some questions unanswered. Firstly, SA treatment often results in a concomitant suppression of the insulin secretion, which might lead to clinically significant glucose intolerance. Secondly, the traditional evaluation of disease activity by measuring circulating levels of GH and total IGF-I is not reliable enough

Inclusion Criteria:

• > 18 years
• treated acromegaly
• considered suitable

Exclusion Criteria:

• pregnancy