Background: Somatostatin analogues are used to treat acromegaly patients who, following surgery, have not fulfilled cure criteria (hGH<2,5 ng/ml, IGF-1 below normal range for age and post-OGTT hGH <1,0 ng/ml). We evaluated the efficacy of Sandostatin LAR in managing such patients.
Material and method: In our Clinic, 81 acromegaly patients (mean age 51.6±14.4 yrs) were registered over the years 1983-2005. Based on CT i MRI, macroadenoma and microadenoma were stated in 63% and 37% of these patients, respectively. 70 patients (86.5%) underwent surgery, 6 (7.4%) refused surgery and 5 (6.1%) underwent radiotherapy., Independently of time after surgery, 60 patients underwent diagnostic tests to qualify them for Sandostatin LAR treatment. Treatment efficacy was based on measuring concentration of hGH i IGF-1 3, 6, 9 and 12 months, and performing control MRI 6 and 12 months after the beginning of Sandostatin LAR treatment (20 mg/month, increased to 30 mg/month if unsatisfactory).
Results: Criteria of post-surgery cure were not fulfilled by 40 patients (66.6% of the 60 evaluated). Due to poor tolerance, one patient was treated with Pegvisomant. 19 patients (31.6%) required no further treatment. After 6 months of treatment, hGH<2.5 ng/ml was stated in 63%, and IGF-1 below normal ranges for age in 58.8% of patients, and after 12 months in 68.4% and 36.8% of patients, respectively. In control MRI, recurrence, correlated with enhanced concentration of IGF-1, was stated in 7 patients (17,5%).
Conclusions: In terms of hGH and IGF-1 levels, satisfactory acromegaly control was obtained in about 40% of patients treated with Sandostatin LAR. This result may be biased by the high number of macroadenoma, and possible non-radical surgery in our patients. Due to evident disparity between 12-month normalization of hGH and of IGF-1 levels, measurements of IGF-1 concentration are of considerable diagnostic value in assessing the activity of acromegaly.