Long-term effects of depot long-acting somatostatin analog octreotide on hormone levels and tumor mass in acromegaly.

Abstract

The effects of a 12- to 24-month treatment with depot long-acting octreotide (OCT-LAR) on hormone profile, tumor mass, and clinical symptoms were reported in 36 patients with active acromegaly [GH, 34.2 +/- 5.6 microg/L; insulin-like growth factor I (IGF-I), 784.5 +/- 40.4 microg/L]. Fifteen patients were de novo whereas 21 had previously undergone unsuccessful surgery. Serum GH (P < 0.0001) and IGF-I levels (P < 0.0001) significantly decreased as early as after the first injection of OCT-LAR and progressively declined during the 12-24 months of treatment both in de novo and in operated patients. At the last follow-up, GH hypersecretion was controlled (< or =2.5 microg/L) in 69.4% whereas normal IGF-I levels were achieved in 61.1% of patients. GH and IGF-I suppression during OCT-LAR treatment was similar in de novo and operated patients as shown by nadir GH (2.3 +/- 0.6 vs. 2.2 +/- 0.6 microg/L) and IGF-I (323.1 +/- 34.9 vs. 275.5 +/- 33.0 microg/L), percent suppression of GH (92.7 +/- 2.0 vs. 85.9 +/- 3.3%) and IGF-I (57.4 +/- 4.9 vs. 61.5 +/- 4.6%), and prevalence of GH (73.3 vs. 76.2%) and IGF-I (53.3 vs. 71.4%) control. A decrease in tumor volume was observed in 12 of 15 de novo patients, whereas no shrinkage was detected in 4 of 9 operated patients. No patient had tumor reexpansion during OCT-LAR treatment. Significant clinical improvement was obtained in all patients; heart rate, systolic blood pressure, and diastolic blood pressure significantly decreased in the entire population. A mild but significant increase of blood glucose levels, followed by a decrease of serum insulin levels, was observed after 3 months of treatment: this effect subsided with treatment continuation. OCT-LAR treatment was well tolerated by most patients. In conclusion, long-term treatment with OCT-LAR was effective in controlling GH and IGF-I hypersecretion in most patients with acromegaly, when applied either as primary therapy or as adjunctive therapy after surgery. Tumor shrinkage was observed in de novo patients during OCT-LAR treatment, suggesting that it can be successfully applied as primary therapy in patients bearing invasive tumors, who are less likely to be cured after surgery.

• Authors: A Colao, D Ferone, P Marzullo, P Cappabianca, S Cirillo, V Boerlin, I Lancranjan, G Lombardi
• Journal: The Journal of clinical endocrinology and metabolism (J Clin Endocrinol Metab) Vol. 86 Issue 6 Pg. 2779-86 (Jun 2001) ISSN: 0021-972X [Print] United States
• PMID: 11397887 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Antineoplastic Agents, Hormonal
• Delayed-Action Preparations
• Hormones
• Human Growth Hormone
• Insulin-Like Growth Factor I
• Octreotide

Topics

• Acromegaly (blood, physiopathology)
• Adenoma (pathology)
• Adult
• Aged
• Antineoplastic Agents, Hormonal (administration & dosage, adverse effects, therapeutic use)
• Delayed-Action Preparations
• Female
• Hormones (blood)
• Human Growth Hormone (blood)
• Humans
• Insulin-Like Growth Factor I (analysis)
• Longitudinal Studies
• Magnetic Resonance Imaging
• Male
• Middle Aged
• Octreotide (administration & dosage, adverse effects, therapeutic use)
• Pituitary Neoplasms (pathology)