BACKGROUND: Gigantism is rare with the majority of cases caused by a growth hormone (GH)-secreting pituitary adenoma. Treatment options for GH-secreting pituitary adenomas have been widened with the availability of long-acting dopamine agonists, depot preparations of somatostatin analogues, and recently the GH receptor antagonist pegvisomant. CASE REPORT: A 23-year-old male patient presented with continuous increase in height during the past 6 years due to a GH-secreting giant pituitary adenoma. Because of major intracranial extension and failure of octreotide treatment to shrink the tumour, the tumour was partially resected by a trans-frontal surgical approach. At immunohistochemistry, the tumour showed a marked expression of GH and a sparsely focal expression of prolactin. Somatostatin receptors (sst) 1-5 were not detected. Tumour tissue weakly expressed dopamine receptor type 2. The Gs alpha subunit was intact. Conversion from somatostatin analogue to pegvisomant normalized insulin-like-growth-factor-I (IGF-I) levels and markedly improved glucose tolerance. CONCLUSION: Pegvisomant is a potent treatment option in patients with pituitary gigantism. In patients who do not respond to somatostatin analogues, knowledge of the SST receptor status may shorten the time to initiation of pegvisomant treatment.
BACKGROUND: Gigantism is rare with the majority of cases caused by a growth hormone (GH)-secreting pituitary adenoma. Treatment options for GH-secreting pituitary adenomas have been widened with the availability of long-acting dopamine agonists, depot preparations of somatostatin analogues, and recently the GH receptor antagonist pegvisomant. CASE REPORT: A 23-year-old male patient presented with continuous increase in height during the past 6 years due to a GH-secreting giant pituitary adenoma. Because of major intracranial extension and failure of octreotide treatment to shrink the tumour, the tumour was partially resected by a trans-frontal surgical approach. At immunohistochemistry, the tumour showed a marked expression of GH and a sparsely focal expression of prolactin. Somatostatin receptors (sst) 1-5 were not detected. Tumour tissue weakly expressed dopamine receptor type 2. The Gs alpha subunit was intact. Conversion from somatostatin analogue to pegvisomant normalized insulin-like-growth-factor-I (IGF-I) levels and markedly improved glucose tolerance. CONCLUSION:Pegvisomant is a potent treatment option in patients with pituitary gigantism. In patients who do not respond to somatostatin analogues, knowledge of the SST receptor status may shorten the time to initiation of pegvisomant treatment.
Authors: Albert Beckers; Maya Beth Lodish; Giampaolo Trivellin; Liliya Rostomyan; Misu Lee; Fabio R Faucz; Bo Yuan; Catherine S Choong; Jean-Hubert Caberg; Elisa Verrua; Luciana Ansaneli Naves; Tim D Cheetham; Jacques Young; Philippe A Lysy; Patrick Petrossians; Andrew Cotterill; Nalini Samir Shah; Daniel Metzger; Emilie Castermans; Maria Rosaria Ambrosio; Chiara Villa; Natalia Strebkova; Nadia Mazerkina; Stéphan Gaillard; Gustavo Barcelos Barra; Luis Augusto Casulari; Sebastian J Neggers; Roberto Salvatori; Marie-Lise Jaffrain-Rea; Margaret Zacharin; Beatriz Lecumberri Santamaria; Sabina Zacharieva; Ee Mun Lim; Giovanna Mantovani; Maria Chaira Zatelli; Michael T Collins; Jean-François Bonneville; Martha Quezado; Prashant Chittiboina; Edward H Oldfield; Vincent Bours; Pengfei Liu; Wouter W de Herder; Natalia Pellegata; James R Lupski; Adrian F Daly; Constantine A Stratakis Journal: Endocr Relat Cancer Date: 2015-02-24 Impact factor: 5.678