title: Remission of acromegaly following long-term therapy with cabergoline: report of two cases.
abstract: Dopamine agonists are effective in some patients with acromegaly and in this condition treatment is considered to be chronic. We describe two acromegalic patients who responded adequately to the long-acting dopamine agonist cabergoline, but surprisingly maintained normal GH and IGF-I levels once therapy was discontinued after 42 and 76 months because of possibly related side effects. A 32-year-old woman with mild acromegaly (IGF-I: 423 microg/l, GH after OGTT: 2.5 microg/l, adenoma 4 mm) was treated with cabergoline as primary therapy and reached safe GH levels (2 microg/l or less) and normal IGF-I levels with 3.5 mg cabergoline weekly. After 42 months of therapy the patient experienced a progressive decrease of libido, which she attributed to the intake of cabergoline. After stopping medication, serum levels of GH and IGF-I remained normal during the following 2.5 years. A 53-year-old man with moderate acromegaly (serum IGF-I: 547 microg/l, GH after OGTT: 5.9 microg/l, adenoma 7 mm) preferred cabergoline as primary therapy. Serum GH levels below 2 microg/l and normal levels of IGF-I were obtained with 3.5 mg cabergoline weekly. When the patient experienced severe stomach pains after 76 months of treatment, cabergoline was held responsible and discontinued. Serum GH and IGF-I did not increase again and stayed at the same level during a follow-up of 5.5 years. These two cases demonstrate that acromegalic patients with a good response to cabergoline may occasionally remain in remission after stopping therapy. This phenomenon has previously only been described in patients with a prolactinoma.
authors.affiliation: Department of Endocrinology, ZNA Middelheim, Lindendreef 1, Antwerp 2020, Belgium. Johan.verhelst@zna.be
authors.forename: Johan A
authors.initials: JA
authors.lastname: Verhelst
authors.forename: Pascale J
authors.initials: PJ
authors.lastname: Abrams
authors.forename: Roger
authors.initials: R
authors.lastname: Abs
mesh_terms: D015746:Abdominal Pain / Q000139:chemically induced; D000172:Acromegaly / Q000097:blood / Q000188:drug therapy*; D000328:Adult; D015415:Biomarkers / Q000097:blood; D000077465:Cabergoline; D018491:Dopamine Agonists / Q000008:administration & dosage* / Q000009:adverse effects; D004334:Drug Administration Schedule; D004873:Ergolines / Q000008:administration & dosage* / Q000009:adverse effects; D005260:Female; D019382:Human Growth Hormone / Q000097:blood; D006801:Humans; D007334:Insulin-Like Growth Factor I / Q000378:metabolism; D007989:Libido / Q000187:drug effects; D008297:Male; D008875:Middle Aged; D055502:Secondary Prevention; D013997:Time Factors; D016896:Treatment Outcome
chemical_list: D015415:Biomarkers; D018491:Dopamine Agonists; D004873:Ergolines; D019382:Human Growth Hormone; D007334:Insulin-Like Growth Factor I; D000077465:Cabergoline