The OASIS study: Therapeutic management of acromegaly in standard clinical practice. Assessment of the efficacy of various treatment strategies

Abstract Background and objectives The reported efficacy of treatments for acromegaly varies depending on reference centers and national registries. The aim of this study was to describe clinical management of this disease and to assess the efficacy of treatments used in standard clinical practice. Material and methods An epidemiological, observational, longitudinal, multicenter study was performed in adult patients with newly diagnosed acromegaly (n = 74) seen by 38 Spanish endocrinologists who collected during routine clinic visits data on disease treatment and control during 2 years of follow-up. Results Pituitary surgery and treatment with somatostatin analogs were the first choice therapies in 76% and 24% of patients, respectively, with no differences related to tumor size. Surgery achieved disease control in 27% of operated patients. After surgery failure, the preferred therapeutic option was somatostatin analogs, which normalized insulin-like growth factor-1 (IGF-I) in 52% of patients and achieved disease control criteria in more than 40% of patients. At the end of follow-up, normal IGF-I levels were found in 63% and 53% of patients with microadenomas and macroadenomas, respectively. Only 19% of patients with macroadenoma met disease control criteria without requiring drug treatment, which was required by 85% of them at some time during follow-up. Conclusions Surgery is the preferred initial treatment for patients with acromegaly, regardless of tumor size. Treatment efficacy in actual clinical practice is far from the success rates reported by reference centers.