Temozolomide Treatment in Aggressive Pituitary Tumors and Pituitary Carcinomas: A French Multicenter Experience
2010; Oxford University Press; Volume: 95; Issue: 10 Linguagem: Inglês
10.1210/jc.2010-0644
ISSN1945-7197
AutoresGérald Raverot, Nathalie Stürm, Florence de Fraipont, Marie Müller, Sylvie Salenave, Philippe Caron, Olivier Chabre, Philippe Chanson, Christine Cortet‐Rudelli, Richard Assaker, Henry Dufour, S. Gaillard, Patrick François, Emmanuel Jouanneau, Jean‐Guy Passagia, Michèle Bernier, Aurélie Cornélius, Dominique Figarella‐Branger, Jacqueline Trouillas, Françoise Borson‐Chazot, Thierry Brue,
Tópico(s)Meningioma and schwannoma management
ResumoTo date only 18 patients with aggressive pituitary tumors or carcinomas treated with temozolomide have been reported. Increased expression of O6-methylguanine-DNA-methyltranferase (MGMT) has been suggested to predict resistance to temozolomide.The objective of the study was to describe the antitumoral efficacy and toxicity of temozolomide in patients with aggressive pituitary tumors or carcinomas and evaluate the possible prognostic value of MGMT promoter methylation and protein expression.Eight patients, five with pituitary carcinomas (three prolactin (PRL) and two ACTH) and three with aggressive pituitary tumors (one PRL and two ACTH), all treated with temozolomide administered orally for four to 24 cycles, were included in our French multicenter study.MGMT expression was assessed by immunohistochemistry and MGMT promoter methylation by pyrosequencing.Three of the eight patients (two ACTH adenomas and one PRL carcinoma) responded to temozolomide as demonstrated by significant tumor shrinkage and reduced hormone secretion. Three cycles of temozolomide were sufficient to identify treatment-responsive patients. Additional cycles did not improve treatment efficacy in those not responding, even when associated with carboplatin and vepeside. MGMT expression did not predict tumoral response to temozolomide because it was positive in one responder and negative in two nonresponders. Similarly, MGMT promoter methylation (three of seven tumors) did not predict clinical response. Toxicity remained mild in all patients.Temozolomide treatment may be an effective option for some aggressive pituitary tumors or carcinomas. Response to a trial of three cycles of treatment seems sufficient to identify responders and more reliable than patient MGMT status.
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