RESUMO
EGFR overexpression in salivary gland carcinomas provides the rational for the investigation of anti-EGFR treatments in recurrent and/or metastatic salivary gland cancers (RMSGCs). The activity of cetuximab in terms of clinical benefit rate (CBR) defined as the occurrence of objective response (CR or PR) or stable disease (SD) for >or=6months was investigated. From April to December 2005, 30 patients [23 adenoid cystic carcinoma (ACC) and 7 non-ACC] were treated with cetuximab at 400mg/m(2)/week followed by 250mg/m(2)/week until progression, major toxicity or voluntary discontinuation. EGFR expression and gene status were retrospectively analyzed by immunocytochemistry and fluorescence in situ hybridization, respectively. A median of 14 courses of cetuximab (range 5-54) were infused. Skin toxicity was the main adverse event. Cetuximab provides a CBR in 50% (95% CL, 31 to 69%) of cases. None tumor sample showed EGFR gene amplification and an increased EGFR copy number was observed in 12% of samples, all ACC. Skin rash >or=G2, EGFR overexpression and EGFR copy number were not statistically correlated to CB. In RMSGCs further evaluations of EGFR targeting agents are advisable and should take place by appropriate tumor biological selection, differentiating ACC from non-ACC.
Assuntos
Anticorpos Monoclonais/uso terapêutico , Antineoplásicos/uso terapêutico , Carcinoma Adenoide Cístico/tratamento farmacológico , Recidiva Local de Neoplasia/tratamento farmacológico , Neoplasias das Glândulas Salivares/tratamento farmacológico , Adolescente , Adulto , Idoso , Anticorpos Monoclonais Humanizados , Carcinoma Adenoide Cístico/metabolismo , Carcinoma Adenoide Cístico/secundário , Cetuximab , Intervalo Livre de Doença , Receptores ErbB/metabolismo , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Hibridização in Situ Fluorescente , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/genética , Recidiva Local de Neoplasia/metabolismo , Cuidados Paliativos/métodos , Estudos Retrospectivos , Neoplasias das Glândulas Salivares/genética , Neoplasias das Glândulas Salivares/metabolismo , Adulto JovemRESUMO
Primary sarcomas of the great vessels are very rare neoplasms and only a few cases have been reported. They are divided into the two broad categories of intimal or luminal and mural sarcomas. We analysed eight advanced high-grade sarcomas originating from major vessels (seven intimal and one mural sarcoma) by means of immunohistochemistry and FISH analysis for PDGFRA, PDGFRB, EGFR and KIT receptor tyrosine kinases (RTKs), together with immunoprecipitation/western blotting, sequencing of the corresponding genes, and the search for cognate ligands. The intimal sarcomas showed a wide spectrum of morphologies and immunophenotypes, whereas the mural sarcoma had common leiomyosarcomatous features. Regardless of their category, all of the cases had a PDGFRA-deregulated cytogenetic profile mainly consisting of an amplification cluster; five were also polysomic for PDGFRB, whereas three showed disomy. Six cases had a deregulated EGFR gene, and c-Kit gene status was similar to that of PDGFRA. In one case, biochemical analysis revealed the presence of activated and highly expressed PDGFRA, PDGFRB and EGFR, whereas KIT was expressed at reference level. Sequencing of the corresponding genes revealed no activating mutations in any of the analysed receptors. The cognate ligands were detected in all cases. In predictive terms, the evidence of gene amplification/high polysomy of several RTKs, together with PDGFRA, PDGFRB and EGFR expression and phosphorylation, suggests that these tumours may be sensitive to RTK-inhibiting treatments.
