A Comparison among the Effectiveness of Growth Hormone Suppression in Active Acromegaly of Bromocriptine and Long Acting Somatostatin Analogue (SMS 201–995)

Summary

The aim of our study was to compare the effectiveness of bromocriptine vs. long acting somatostatin analogue (SMS 201—995) on growth hormone suppression in active acromegaly.A twenty year old female, student of law, was previously treated with Parlodel LA 50 mg i.m. injection and then with bromocriptine 30 mg orally for 2.5 years because of active acromegaly and very large intrasellar and suprasellar pituitary adenoma. She was partial bromocriptine responder with mean growth hormone levels prior the treatment 30 mU/L and after bromocriptine 13.7 mU/L and with gross tumor shrinkage. Since she failed to restore menstrual cycles, had clinical signs of the disease, she was taken off bromocriptine and treated with somatostatin analogue (SMS 201—995) 300 mcg s. c daily and 400 mcg s. c daily with mean growth hormone levels 10 mU/L. She was also treated with combined treatment (400 mcg s.c. SMS 201—995 plus 30 mg bromocriptine orally) and mean growth hormone levels were 11 mU/L. SMS 201—995 had a long lasting inhibitory effect on growth hormone secretion in acromegaly (p < 0.01) but in comparison to daily growth hormone levels during bromocriptine treatment no difference was found (p > 0.1). Combined treatment with SMS 201—995 and bromocriptine did not achieve greater suppression of daily growth hormone levels than those achieved with SMS 201—995 alone (p > 0.1) or with bromocriptine alone (p > 0.05). No significant tumor shrinkage during chronic SMS treatment was seen. Severe clinical and biochemical signs of hypoglyoaemia were registered on one occasion only during the first month of treatment with SMS 201—995. Chronic treatment with SMS 201—995 can be considered as adjuvant to surgery or radiotherapy in the management of acromegaly and careful monitoring of the side effects are necessary.

Key words

Somatostatin analogue - Bromocriptine - Acromegaly