[Experience in treating acromegalic patients with long-acting octreotide]

The authors report clinical observations in 12 acromegalic patients treated with long-acting octreotide (Sandostatin LAR, Novartis, 20 mg intramuscular injection per 28 days administered for 6-36 months). Clinically and hormonally active acromegaly was evidenced in all patients by the presence of typical clinical symptoms, increased serum growth hormone and insulin-like growth factor I concentrations, and by non-suppressible serum growth hormone levels after oral glucose administration. In all patients previous treatments (transsphenoidal surgery, pituitary irradiation and bromocriptine therapy) were uneffective or contraindicated, or they were refused by the patients. Octreotide test (Sandostatin, Novartis, 100 g subcutaneously) performed in all patients before treatment precisely predicted the hormonal effectiveness of long-acting octreotide treatment. Three-six months after therapy serum growth hormone levels decreased from 13.6 +/- 3.9 ng/ml (mean +/- SD) to 3.4 +/- 1.7 ng/ml, while insulin-like growth factor I concentrations decreased from 483 +/- 127 ng/ml to 248 +/- ng/ml. Of the 12 patients 7 (58%) had serum growth hormone levels considered as safe values (< 2.5 ng/ml), whereas in 9 patients (75%) serum insulin-like growth factor I concentrations returned to age- and sex-matched normals. Repeat pituitary magnetic resonance imaging performed in 8 patients treated longer than 1 year revealed a decrease of tumor size in 3 patients (37%). There was a considerable clinical improvement during treatment: severe headache, which was present in most patients, as well as perspiration, joint pain, swelling of extremities, and weakness markedly decreased or disappeared. These results indicate that long-acting octreotide offers a very effective treatment of choice in acromegalic patients in whom other previous therapies were ineffective, contraindicated, or refused.