Evaluation of the efficacy of Octreotide LAR in the treatment of acromegaly--a yearly observation

Since acromegaly is associated with high rates of comorbidities and increased mortality risk compared to the general population, over the last few years somatostatin analogues have been used to treat acromegaly patients who, following surgery, have not fulfilled cure criteria (basal hGH < 2.5 ng/ml, IGF-1 below normal ranges for age and sex and hGH < 1.0 ng/ml in the 120th min of the OGTT test). We assessed the efficacy of Octreotide LAR (OCT-LAR) in managing such patients. 72 patients underwent diagnostic tests to qualify them for Octreotide LAR treatment. Treatment efficacy evaluation was based on measuring the concentration of hGH and IGF-1 prior to and 3 and 12 months and performing control MRI 6 and 12 months after the beginning of OCT-LAR treatment. The dose of O ctreotide LAR was 20 mg/month, increased to 30 mg/month if unsatisfactory response was observed. We evaluated the efficacy of Octreotide LAR in 48 acromegaly patients (66.7% of 72 evaluated), in whom criteria of postsurgery cure were not fulfilled. 24 patients (33.3%) did not require further treatment. After 3 months of OCT-LAR treatment, hGH < 2.5 ng/ml was stated in 37.0% of patients, median value--3.4 ng/ml (IQR = 5.3), as compared to median value of 5.5 ng/ml (IQR = 5.6) before treatment (p < 0.05). After 3 months of treatment IGF-1 below normal ranges for age and sex was stated in 55.5% of patients, median value--336.8 ng/ml (IQR = 290.0), as compared to median value of 520.0 ng/ml (IQR = 351.0) prior to OCT-LAR treatment (p < 0.05). After 12 months hGH < 2.5 ng/l ml and IGF-1 below normal ranges for age and sex were found in 63.0% and 54.5% of patients, respectively. In control MRI recurrence, correlated with enhanced concentration of IGF-1, was stated in 7 patients (14.6%). Thus, we conclude that satisfactory acromegaly control, in terms of hGH and IGF-1 levels, was obtained in above 50% of patients treated with Octreotide LAR. Since in the studied group hGH secretion had achieved cure criteria after 3 months in 37.5% as compared to 63.0% after 12-months, assessment of OCT-LAR treatment should be extended over periods exceeding 3 months.