Endocrine Abstracts

Introduction: Somatostatin analogs, formerly used as adjuvants in acromegaly treatment, are widely used as primary treatment today.

Objective: To investigate the efficacy of octreotide therapy in acromegalic patients as primary or secondary therapy.

Materials and methods: Four acromegalic patients diagnosed at the Endocrinological Clinic (males, mean age 35–75 years, age range 26–49 years, all patients with macroadenoma) were treated with octreotide. Among them, three patients received octreotide preoperatory and one postoperatory. The concentration of human GH (HGH) and IGF1 was evaluated at 0, 6 and 12 months, while magnetic resonance imaging (MRI) was taken before treatment and 12 months after. All pacients received initially octreotide 20 mg/28 days. The dose was adjusted by the individual patient’s response. Mean treatment duration was 25–75 months (range 6–43 months).

Results: Mean serum GH fell from 53 ng/ml (range 51.7–130.6) to 13 ng/ml (range 2.03–29.83) at the 3 months visit and remained suppressed. Mean plasma IGF1 concentrations fell from 502.5 ng/ml (range 327–838) to 490.25 ng/ml (range 320–677) at three months. Patients with higher initial GH concentrations were less likely to normalize IGF1 concentrations during treatment. After 1-year of therapy, tumor size decreased with a mean value of 22.58% in 75% of cases. Dose increments above 30 mg/28 days at one patient did not provide additional benefit in terms of hormonal reduction. The symptoms were ameliorated in 75% of patients. The most common adverse events were gastrointestinaly; one patient developed gallstones but was asymptomatic.

Conclusions: Octreotide treatment of acromegaly not only decreases GH and IGF1 concentrations, but also appears to diminish the size of the tumor.