RESUMO
INTRODUCTION: Frequency of mutations in EGFR and KRAS in non-small cell lung cancer (NSCLC) is different between ethnic groups; however, there is no information in Latin-American population. METHODS: A total of 1150 biopsies of NSCLC patients from Latin America (Argentina, Colombia, Peru, and Mexico) were used extracting genomic DNA to perform direct sequencing of EGFR gene (exons 18 and 21) and KRAS gene in 650 samples. In Mexico, Scorpions ARMS was also used to obtain a genetic profile. RESULTS: We report the frequency of mutations in EGFR and KRAS genes in four Latin-American countries (n = 1150). Frequency of EGFR mutations in NSCLC was 33.2% (95% confidence interval [CI] 30.5-35.9) (Argentina 19.3%, Colombia 24.8%, Mexico 31.2%, and Peru 67%). The frequency of KRAS mutations was 16.6% (95% CI 13.8-19.4). EGFR mutations were independently associated with adenocarcinoma histology, older age, nonsmokers, and absence of KRAS mutations. Overall response rate to tyrosine kinase inhibitors in EGFR-mutated patients (n = 56) was 62.5% (95% CI 50-75) with a median overall survival of 16.5 months (95% CI 12.4-20.6). CONCLUSIONS: Our findings suggest that the frequency of EGFR mutations in Latin America lies between that of Asian and Caucasian populations and therefore support the genetic heterogeneity of NSCLC around the world.
Assuntos
Carcinoma Pulmonar de Células não Pequenas/genética , Receptores ErbB/genética , Neoplasias Pulmonares/genética , Mutação/genética , Proteínas Proto-Oncogênicas/genética , Proteínas ras/genética , Adenocarcinoma/epidemiologia , Adenocarcinoma/genética , Ásia/epidemiologia , Carcinoma de Células Grandes/epidemiologia , Carcinoma de Células Grandes/genética , Carcinoma Pulmonar de Células não Pequenas/epidemiologia , Carcinoma de Células Escamosas/genética , DNA de Neoplasias/genética , Feminino , Genótipo , Humanos , América Latina/epidemiologia , Neoplasias Pulmonares/epidemiologia , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Prognóstico , Proteínas Proto-Oncogênicas p21(ras) , População BrancaRESUMO
PURPOSE: We performed this double-blinded, placebo-controlled study to determine the safety and efficacy of L-alanyl-L-glutamine in the prevention of mucositis in patients with head-and-neck cancer. METHODS AND MATERIALS: Thirty-two patients with head-and-neck cancer were treated with chemoradiotherapy (CRT) (radiotherapy daily up to 70 Gy plus cisplatin/5-fluoruracil once a week) and were asked to participate. Twenty-nine patients received the CRT schedule and were double-blindly assigned to receive either intravenous L-alanyl-L-glutamine 0.4 g/kg weight/day or an equal volume of saline (placebo) during chemotherapy days. RESULTS: Fourteen patients received L-alanyl-L-glutamine and 15 received placebo. Mucositis was assessed by the Objective Mucositis Score (OMS) and the World Health Organization (WHO) grading system. There was a significant difference in incidence of mucositis developed in patients receiving placebo compared with those who received L-alanyl-L-glutamine (p = 0.035). The number of patients with severe objective mucositis (OMS >1.49) was higher in the placebo group compared with the L-alanyl-L-glutamine group (67% vs. 14%, p = 0.007). L-alanyl-L-glutamine patients experienced less pain (three highest Numeric Rating Scale scores of 1.3/10 vs. 6.3/10 respectively, p = 0.008) and need for feeding tubes (14% vs. 60% respectively, p = 0.020) compared with placebo patients. No adverse effects related to the drug or the infusions were noted in either group. CONCLUSION: For patients with head-and-neck cancer receiving CRT, intravenous L-alanyl-L-glutamine may be an effective preventive measure to decrease the severity of mucositis.
