Clinical Experience with Sandostatin LAR in Patients with Acromegaly

Abstract

Introduction: Depot preparations of long-acting somatostatin analyses are used in the treatment of hyper secretion of growth hormone (GH) in patients with acromegaly as primary or secondary treatment after incomplete surgery when the disease remained active. Recently, in the clinical practice at the Clinic for Endocrinology, Diabetes and metabolic disorders the long acting octreotide (Sandostatin LAR) became available. Objective: To assess the effectiveness and safety of treatment with long-acting octreotide (Sandostatin LАR). Material and Methods: It is a retrospective analysis of patients with acromegaly and pituitary somatotroph adenoma treated in the period 2010 to 2014. Data were obtained from the Register of Acromegaly. Followed in 28 patients (15 men and 13 women), aged 24 to 59 years of which 3 had microadenoma and the others had pituitary macroadenoma. Treatment lasted from 6 months to 2 years. Because cardiovascular problems 3 patients were immediately placed on therapy with Sandostatin LAR, and the rest underwent surgical treatment. Because of disease activity after surgery,4 patients underwent another surgical treatment,12 were irradiated, out of which 5 with stereotoxic radiosurgery (gamma knife) and 10 were set on additional adjuvant therapy with Sandostatin LAR. All patients received a dose of 20 mg i.m Sandostatin LAR on every 28 days. Results: We found suppression of growth hormone and growth factor similar to insulin (IGF-I) during the entire follow-up period. In one patient due to the persistence of high IGF-1 an increase of the dose to 30 mg was needed and in other a reduction in the dose of 10 mg. Reduction of tumor size was observed in both groups of patients where octreotide was given as primary or adjuvant therapy. We also found changes in glucose metabolism assessed by oral glucose tolerance test and hemoglobin A1C during treatment, but not in thyroid function (TSH and free T4). Three patients developed asymptomatic biliary calculi, out of whom one developed an acute pancreatitis and had to undergo a cholecystectomy. Conclusion: Treatment of acromegaly with Sandostatin LAR not only reduces GH and IGF1 concentrations, but it also acts to reduce the size of the tumor. The medicine is well tolerated during long-term treatment and can be considered as the treatment of choice for patients with acromegaly.