Long-term (up to 18 years) effects on GH/IGF-1 hypersecretion and tumour size of primary somatostatin analogue (SSTa) therapy in patients with GH-secreting pituitary adenoma responsive to SSTa.
BACKGROUND
The role of somatostatin analogues (SSTa) in the treatment of acromegaly.


OBJECTIVE
To evaluate the antihormonal and antitumour efficacy of long-term (up to 18 years) primary treatment with SSTa in patients with GH-secreting pituitary adenoma responsive to SSTa.


METHODS
An open, prospective, single-centre, clinical study.


METHODS
Thirty-six acromegalic patients, aged 17-75 years (postoral glucose tolerance test GH > 1 microg/l, increased IGF-1 for age and sex), were monitored in a single centre and treated with SSTa as first-line therapy. The mean pretreatment GH level was 13.5 +/- 3.1 microg/l, and IGF-1 (as a percentage of the value over the normal range) was 302 +/- 26%. The patients had macroadenoma (n = 25), microadenoma (n = 8) or empty sella turcica (n = 3). The mean duration of treatment was 8 years (range 3-18 years). Hormonal and morphological monitoring was undertaken after 6 months, and then the patients were followed annually.


RESULTS
After 1 year, the mean GH and IGF-1 levels had reduced considerably (GH: 2.4 +/- 0.3 microg/l; IGF-1; 174 +/- 14%, P < 0.01), and they continued to decrease over 10 years, with a mean GH level of 1.6 +/- 0.1 microg/l and IGF-1 of 123 +/- 18% (P = 0.02). GH < 2 microg/l, normal IGF-1, or both were observed in 25 (70%), 24 (67%) and 21 (58%) patients, respectively. The mean reduction in tumour volume was 43% (range 13-97%) and shrinkage > 20% was obtained in 21 patients (72%). SSTa treatment was well tolerated with few digestive or metabolic side-effects.


CONCLUSIONS
Long-term (up to 18 years) treatment with SSTa used as first-line therapy is effective from both an antihormonal and antitumour perspective, and is well tolerated in acromegalic patients.
Maiza
Jean Christophe
JC
Department of Endocrinology, CHU Rangueil, 31059 Toulouse, France.
Vezzosi
Delphine
D
Matta
Maria
M
Donadille
Florence
F
Loubes-Lacroix
Florence
F
Cournot
Maxime
M
Bennet
Antoine
A
Caron
Philippe
P
D000293:Adolescent; D000328:Adult; D000368:Aged; D018931:Antineoplastic Agents, Hormonal / Q000627:therapeutic use*; D016009:Chi-Square Distribution; D018491:Dopamine Agonists / Q000627:therapeutic use; D005260:Female; D005500:Follow-Up Studies; D013006:Growth Hormone / Q000097:blood*; D049912:Growth Hormone-Secreting Pituitary Adenoma / Q000097:blood / Q000188:drug therapy* / Q000473:pathology; D006801:Humans; D007334:Insulin-Like Growth Factor I / Q000032:analysis*; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D015282:Octreotide / Q000627:therapeutic use; D010456:Peptides, Cyclic / Q000627:therapeutic use; D010911:Pituitary Neoplasms / Q000097:blood / Q000188:drug therapy* / Q000473:pathology; D011446:Prospective Studies; D013004:Somatostatin / Q000031:analogs & derivatives* / Q000627:therapeutic use; D018709:Statistics, Nonparametric; D014057:Tomography, X-Ray Computed; D016896:Treatment Outcome
D018931:Antineoplastic Agents, Hormonal; D018491:Dopamine Agonists; D010456:Peptides, Cyclic; C060347:lanreotide; D013004:Somatostatin; D007334:Insulin-Like Growth Factor I; D013006:Growth Hormone; D015282:Octreotide