SFEBES2009 Poster Presentations Pituitary (65 abstracts)
1Christie Hospital, Manchester, UK; 2Hospital, Orleans, France; 3University of Geneva, Geneva, Italy; 4University, Berlin, Germany; 5Aarhus University Hospital, Aarhus, Denmark; 6Rigshospitalet, Copenhagen, Denmark; 7University of Padua, Padua, Italy; 8San Martino University Hospital, Genoa, Italy; 9Pfizer Endocrine Care, Solluntuna, Sweden; 10Lapeyronie Hospital, Montpellier, France; 11University of Bonn, Bonn, Germany; 12Klinikum Chemnitz, Chemnitz, Germany.
Gigantism is an extremely rare condition and hence the relevant literature is largely a series of case reports. We present data on patients with gigantism <20 years of age identified from Pfizers Acrostudy registry of patients treated with pegvisomant.
Eleven patients (5M) were identified: IGF1 at diagnosis was 1.6×ULN (1.153.3), height +5 SDS (1.13.8) and age 14.5 years (419). The three youngest (4, 7 and 14 years) had pituitary hyperplasia secondary to NF-1 (n=1) or McCuneAlbright (n=2). The remaining eight had macroadenomas and had transsphenoidal surgery (TSS) as first line treatment. Two patients had a second TSS, and one had two TSS followed by a craniotomy. Four subsequently had radiotherapy. Four patients had hyperprolactinemia at diagnosis, seven were treated post-surgery with cabergoline (median dose=1.75 mg/week (0.257)). All patients received octreotide LAR (median duration of 12 months (6120), dose 30 mg/month (1040). IGF1 was elevated in all patients prior to starting pegvisomant. On pegvisomant (median dose 20 mg/day (1030 mg), duration 4.5 years (2.56)) monotherapy (n=8) or in combination with cabergoline (n=2) or octreotide (n=1) all patients achieved IGF1 within the reference range. There have been no significant adverse events reported or increases in tumour size measured during pegvisomant therapy.
Syndromic gigantism is more common in patients with early presentation and in such patients surgery may be avoided. Vigorous and prompt treatment is required to minimise the harm from excessive GH, particularly tall stature. Radiotherapy may be more rapidly effective than in adults (data not shown) although the long-term risks are unknown. Somatostatin analogues and dopamine agonists are effective but despite all conventional treatment a significant number of patients remain uncontrolled. Experience from 11 patients treated with pegvisomant suggests that it is a safe and effective treatment in this group.