Lefebvre S, De Paepe L, Abs R, Rahier J, Selvais P, Maiter D. Subcutaneous octreotide treatment of a growth hormone-releasing hormone-secreting bronchial carcinoid: superiority of continuous versus intermittent administration to control hormonal secretion. Eur J Endocrinol 1995;133:320–4. ISSN 0804–4643
Diagnosis of ectopic acromegaly was made in a 21-year-old female patient who 3 years before had undergone a right pneumectomy for a disseminated bronchial carcinoid. Plasma growth hormonereleasing hormone (GHRH) concentrations were markedly elevated (6440 ng/l; normal value <100 ng/l), as were serum GH (187 μg/l; normal <5 μg/l) and plasma insulin-like growth factor I (IGF-I) levels (6.7 U/ml; normal <2 U/ml). Retrospective immunohistochemical examination of the carcinoid tumor was positive for GHRH and the tumoral content of GHRH was 2130 ng/g wet weight. Subcutaneous treatment with octreotide was begun and first resulted in a profound inhibition of GH hypersecretion, normalization of plasma IGF-I and only partial reduction of GHRH concentrations. However, the initial dose of 3 × 100 μg had to be increased gradually to 4 × 750 μg because of a progressive deterioration of the hormonal control. After 15 months of intermittent therapy, octreotide was administered by continuous sc infusion. This treatment improved compliance, allowed the daily dose of octreotide to be reduced to 1500 μg and normalized serum GH levels. A near-normalization of the plasma IGF-I concentrations was also obtained, whereas the suppression of plasma GHRH concentrations remained incomplete. Despite favorable evolution of the endocrine parameters, intramedullar metastases were diagnosed and required radiation therapy. This observation emphasizes the superiority of continuous over intermittent administration of octreotide in the treatment of ectopic acromegaly. It also shows that the somatostatin analog acts more at the pituitary level to inhibit GH secretion than at the site of the neuroendocrine tumor.
S Lefebvre, Division of Rheumatology, Clinique du Refuge, Rue du Couvent 39, B-7700 Mouscron, Belgium
Ectopic growth hormone-releasing hormone secretion by a bronchial carcinoid tumor: clinical experience following tumor resection and long-acting octreotide therapy
