Insulin-like growth factor binding protein-3 levels during early and late follow-up after surgery in acromegalic patients.

Abstract

Disease activity in acromegaly is accurately reflected by growth hormone (GH) concentration during oral glucose tolerance test (OGTT) and insulin-like growth factor-I (IGF-I) levels, representing an integrated index of GH activity. This prospective study was performed to evaluate whether plasma IGF binding protein 3 (IGFBP-3) might also reflect the hormonal disease activity in pituitary acromegaly after operative treatment during early and late follow-up. Twenty-two acromegalic patients were studied. Data were obtained pre-, intra- and post-operatively in 13 cases. In 9 patients the acromegalic activity was studied only after treatment. The hormonal assessment included repeated blood samples for estimation of IGF-I, IGFBP-3 and repeated OGTTs. In each case 100 sigma g octreotide (Sandostatin lambda, Sandoz, Basel) was injected to test the acute response of GH, IGF-I and IGFBP-3. Intraoperatively, GH levels were estimated to examine acutely the influence of tumour reduction on GH levels. Patients were considered cured when GH levels (GH60min) were less than 2 ng/ml during OGTT 4 weeks after surgery. The data outlined that in patients with normalized GH60min levels, normalized IGFBP-3 levels were noticed 4 weeks and 12 months post-operatively. In non-cured patients normalized IGFBP-3 concentrations were found in 11 out of 15 cases in the late post-treatment phase. In contrast only 1 of 7 cured patients had persistently elevated IGF-I levels within the first month post-operatively, whereas no case of the non-cured patients had IGF-I values in the normal range. Despite these observations a strong correlation of IGF-I and IGFBP-3 did not exist before one year post-operatively -- either in the cured or in the non-cured patients. Serum IGFBP-3 in patients with pituitary acromegaly does not provide a predictive value of appreciable magnitude concerning cure or non-cure from the disease- whether examined early or late in the post-operative period. Absolute levels of IGFBP-3 may thus cause misinterpretation concerning cure of acromegalics after surgery.

• Authors: P Charalampaki, G Hildebrandt, H J Schaeffer, E Schönau, N Klug
• Journal: Experimental and clinical endocrinology & diabetes : official journal, German Society of Endocrinology [and] German Diabetes Association (Exp Clin Endocrinol Diabetes) Vol. 106 Issue 2 Pg. 130-4 ( 1998) ISSN: 0947-7349 [Print] Germany
• PMID: 9628244 (Publication Type: Journal Article)

Chemical References

• Hormones
• Insulin-Like Growth Factor Binding Protein 3
• Insulin-Like Growth Factor I
• Growth Hormone
• Octreotide

Topics

• Acromegaly (blood, drug therapy, surgery)
• Adult
• Aged
• Female
• Follow-Up Studies
• Glucose Tolerance Test
• Growth Hormone (blood, drug effects)
• Hormones (therapeutic use)
• Humans
• Insulin-Like Growth Factor Binding Protein 3 (blood, drug effects)
• Insulin-Like Growth Factor I (drug effects, metabolism)
• Male
• Middle Aged
• Octreotide (therapeutic use)
• Postoperative Period
• Prospective Studies
• Time Factors