Role of the addition of cabergoline to the management of acromegalic patients resistant to longterm treatment with octreotide LAR

• Published in: Pituitary 2011-06, Vol.14 (2), p.148-156
• Main Authors: Vilar, Lucio, Azevedo, Monalisa F., Naves, Luciana Ansaneli, Casulari, Luiz Augusto, Albuquerque, José Luciano, Montenegro, Renan M., Figueiredo, Patricia, Nascimento, Gilvan C., Faria, Manuel S.
• Format: Article
• Language: English
• Subjects: Acromegaly - drug therapy; Acromegaly - etiology; Adenoma - complications; Adenoma - drug therapy; Adult; Aged; Antineoplastic Combined Chemotherapy Protocols - therapeutic use; Delayed-Action Preparations - administration & dosage; Drug Resistance, Neoplasm - drug effects; Endocrinology; Ergolines - administration & dosage; Ergolines - pharmacology; Female; Growth Hormone-Secreting Pituitary Adenoma - complications; Growth Hormone-Secreting Pituitary Adenoma - drug therapy; Human Physiology; Humans; Insulin-Like Growth Factor I - administration & dosage; Insulin-Like Growth Factor I - therapeutic use; Male; Medicine; Medicine & Public Health; Middle Aged; Octreotide - administration & dosage; Time Factors; Young Adult
• ISSN: 1386-341X; 1573-7403
• DOI: 10.1007/s11102-010-0272-1

The aim of this prospective open trial was to evaluate the efficacy in normalizing IGF-I levels of the addition of cabergoline to the treatment of acromegalic patients partially responsive to Octreotide-LAR (OCT-LAR), a long acting somatotastin analog (SSA). Fifty-two patients who did not achieve hormonal control after longterm therapy (at least, 12 months) with OCT-LAR (30 mg every 28 days intramuscularly) were given cabergoline in addition to the SSA treatment. Normalization of IGF-I levels was achieved in 40.4% of patients by 6 months after the addition of cabergoline (1.0–3.0 mg/week; mean, 2.19 ± 0.64), and these patients were considered responsive. Compared to non-responsive subjects, responsive patients had significantly lower mean %ULNR-IGF-I and GH levels. However, the rate of hyperprolactinemia and positive immunohistochemical staining for PRL was similar in both groups, before the addition of cabergoline. Responsive patients were followed for at least 12 months on combination treatment and persisted with normal IGF-I levels. Patients with baseline %ULNR IGF-I up to 220% and/or GH up to 5 ng/ml were those who benefited the most from combination treatment. No patients with %ULNR-IGF-I > 250% reached normalization of IGF-I levels. Our findings demonstrated that the addition of cabergoline, even at relatively low doses, is effective in both short- and long-term control of IGF-I levels in acromegalic patients partially responsive to octreotide LAR, particularly in those with mild/moderately elevated GH/IGF-levels, irrespective of prolactin status.