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BACKGROUND: In order to obtain a deeper understanding of an incident, it needs to be investigated to "peel back the layers" and examine both immediate and underlying failures that contributed to the event itself. One of the key elements of an effective accident investigation is recording the scene for future reference. In recent years, however, there have been major advances in survey technology, which have provided the ability to capture scenes in three dimension to an unprecedented level of detail, using laser scanners. METHODS: A case study involving a fatal incident was surveyed using three-dimensional laser scanning, and subsequently recreated through virtual and physical models. The created models were then utilized in both accident investigation and legal process, to explore the technologies used in this setting. RESULTS: Benefits include explanation of the event and environment, incident reconstruction, preservation of evidence, reducing the need for site visits, and testing of theories. Drawbacks include limited technology within courtrooms, confusion caused by models, cost, and personal interpretation and acceptance in the data. CONCLUSION: Laser scanning surveys can be of considerable use in jury trials, for example, in case the location supports the use of a high-definition survey, or an object has to be altered after the accident and it has a specific influence on the case and needs to be recorded. However, consideration has to be made in its application and to ensure a fair trial, with emphasis being placed on the facts of the case and personal interpretation controlled.
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AIMS: Activating mutations in the gene encoding epidermal growth factor receptor (EGFR) can confer sensitivity to EGFR tyrosine kinase inhibitors such as gefitinib in patients with advanced non-small-cell lung cancer. Testing for mutations in EGFR is therefore an important step in the treatment-decision pathway. We reviewed reported methods for EGFR mutation testing in patients with lung cancer, initially focusing on studies involving standard tumour tissue samples. We also evaluated data on the use of cytology samples in order to determine their suitability for EGFR mutation analysis. METHODS: We searched the MEDLINE database for studies reporting on EGFR mutation testing methods in patients with lung cancer. RESULTS: Various methods have been investigated as potential alternatives to the historical standard for EGFR mutation testing, direct DNA sequencing. Many of these are targeted methods that specifically detect the most common EGFR mutations. The development of targeted mutation testing methods and commercially available test kits has enabled sensitive, rapid and robust analysis of clinical samples. The use of screening methods, subsequent to sample micro dissection, has also ensured that identification of more rare, uncommon mutations is now feasible. Cytology samples including fine needle aspirate and pleural effusion can be used successfully to determine EGFR mutation status provided that sensitive testing methods are employed. CONCLUSIONS: Several different testing methods offer a more sensitive alternative to direct sequencing for the detection of common EGFR mutations. Evidence published to date suggests cytology samples are viable alternatives for mutation testing when tumour tissue samples are not available.
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Carcinoma de Pulmón de Células no Pequeñas/genética , Análisis Mutacional de ADN , Receptores ErbB/genética , Neoplasias Pulmonares/genética , Mutación , Manejo de Especímenes , Antineoplásicos/uso terapéutico , Biopsia con Aguja , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Carcinoma de Pulmón de Células no Pequeñas/enzimología , Carcinoma de Pulmón de Células no Pequeñas/patología , Citodiagnóstico , Análisis Mutacional de ADN/instrumentación , Análisis Mutacional de ADN/métodos , Humanos , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/enzimología , Neoplasias Pulmonares/patología , Microdisección , Selección de Paciente , Derrame Pleural/enzimología , Derrame Pleural/genética , Derrame Pleural/patología , Medicina de Precisión , Valor Predictivo de las Pruebas , Inhibidores de Proteínas Quinasas/uso terapéutico , Juego de Reactivos para Diagnóstico , Sensibilidad y Especificidad , Manejo de Especímenes/métodosRESUMEN
PURPOSE: The results of the Iressa Pan-Asia Study (IPASS), which compared gefitinib and carboplatin/paclitaxel in previously untreated never-smokers and light ex-smokers with advanced pulmonary adenocarcinoma were published previously. This report presents overall survival (OS) and efficacy according to epidermal growth factor receptor (EGFR) biomarker status. PATIENTS AND METHODS: In all, 1,217 patients were randomly assigned. Biomarkers analyzed were EGFR mutation (amplification mutation refractory system; 437 patients evaluable), EGFR gene copy number (fluorescent in situ hybridization; 406 patients evaluable), and EGFR protein expression (immunohistochemistry; 365 patients evaluable). OS analysis was performed at 78% maturity. A Cox proportional hazards model was used to assess biomarker status by randomly assigned treatment interactions for progression-free survival (PFS) and OS. RESULTS: OS (954 deaths) was similar for gefitinib and carboplatin/paclitaxel with no significant difference between treatments overall (hazard ratio [HR], 0.90; 95% CI, 0.79 to 1.02; P = .109) or in EGFR mutation-positive (HR, 1.00; 95% CI, 0.76 to 1.33; P = .990) or EGFR mutation-negative (HR, 1.18; 95% CI, 0.86 to 1.63; P = .309; treatment by EGFR mutation interaction P = .480) subgroups. A high proportion (64.3%) of EGFR mutation-positive patients randomly assigned to carboplatin/paclitaxel received subsequent EGFR tyrosine kinase inhibitors. PFS was significantly longer with gefitinib for patients whose tumors had both high EGFR gene copy number and EGFR mutation (HR, 0.48; 95% CI, 0.34 to 0.67) but significantly shorter when high EGFR gene copy number was not accompanied by EGFR mutation (HR, 3.85; 95% CI, 2.09 to 7.09). CONCLUSION: EGFR mutations are the strongest predictive biomarker for PFS and tumor response to first-line gefitinib versus carboplatin/paclitaxel. The predictive value of EGFR gene copy number was driven by coexisting EGFR mutation (post hoc analysis). Treatment-related differences observed for PFS in the EGFR mutation-positive subgroup were not apparent for OS. OS results were likely confounded by the high proportion of patients crossing over to the alternative treatment.
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Adenocarcinoma/tratamiento farmacológico , Antineoplásicos/uso terapéutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Biomarcadores de Tumor/análisis , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Receptores ErbB/análisis , Neoplasias Pulmonares/tratamiento farmacológico , Inhibidores de Proteínas Quinasas/uso terapéutico , Quinazolinas/uso terapéutico , Adenocarcinoma/química , Adenocarcinoma/genética , Adenocarcinoma/mortalidad , Adenocarcinoma/patología , Adenocarcinoma del Pulmón , Anciano , Asia , Biomarcadores de Tumor/genética , Carboplatino/administración & dosificación , Carcinoma de Pulmón de Células no Pequeñas/química , Carcinoma de Pulmón de Células no Pequeñas/genética , Carcinoma de Pulmón de Células no Pequeñas/mortalidad , Carcinoma de Pulmón de Células no Pequeñas/patología , Supervivencia sin Enfermedad , Receptores ErbB/antagonistas & inhibidores , Receptores ErbB/genética , Femenino , Gefitinib , Dosificación de Gen , Humanos , Inmunohistoquímica , Hibridación Fluorescente in Situ , Estimación de Kaplan-Meier , Modelos Logísticos , Neoplasias Pulmonares/química , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/mortalidad , Neoplasias Pulmonares/patología , Masculino , Persona de Mediana Edad , Mutación , Oportunidad Relativa , Paclitaxel/administración & dosificación , Selección de Paciente , Medicina de Precisión , Valor Predictivo de las Pruebas , Modelos de Riesgos Proporcionales , Medición de Riesgo , Factores de Riesgo , Tasa de Supervivencia , Factores de Tiempo , Resultado del TratamientoRESUMEN
Vandetanib is a multi-targeted receptor tyrosine kinase inhibitor that is in clinical development for the treatment of solid tumours. This preclinical study examined the inhibition of two key signalling pathways (VEGFR-2, EGFR) at drug concentrations similar to those achieved in the clinic, and their contribution to direct and indirect antitumour effects of vandetanib. For in vitro studies, receptor phosphorylation was assessed by Western blotting and ELISA, cell proliferation was assessed using a cell viability endpoint, and effects on cell cycle determined using flow cytometry. For in vivo studies, Western blotting, ELISA and immunohistochemistry (IHC) were used to assess receptor phosphorylation. Cell culture experiments demonstrated that anti-proliferative effects of vandetanib resulted from inhibition of either EGFR or VEGFR-2 signalling in endothelial cells, but were associated with inhibition of EGFR signalling in tumour cells. Vandetanib inhibited both EGFR and VEGFR-2 signalling in normal lung tissue and in tumour xenografts. In a lung cancer model expressing an activating EGFR mutation, the activity of vandetanib was similar to that of a highly selective EGFR inhibitor (gefitinib), and markedly greater than that of a highly selective VEGFR inhibitor (vatalanib). These data suggest that at the plasma exposures achieved in the clinic, vandetanib will significantly inhibit both VEGFR-2 and EGFR signalling, and that both inhibition of angiogenesis and direct inhibition of tumour cell growth can contribute to treatment response.
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Antineoplásicos/farmacología , Receptores ErbB/antagonistas & inhibidores , Piperidinas/farmacología , Quinazolinas/farmacología , Transducción de Señal/efectos de los fármacos , Receptor 2 de Factores de Crecimiento Endotelial Vascular/antagonistas & inhibidores , Animales , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Modelos Animales de Enfermedad , Células Endoteliales/efectos de los fármacos , Receptores ErbB/metabolismo , Femenino , Humanos , Ratones , Ratones SCID , Neoplasias/fisiopatología , Fenotipo , Receptor 2 de Factores de Crecimiento Endotelial Vascular/metabolismo , Ensayos Antitumor por Modelo de XenoinjertoRESUMEN
BACKGROUND: We have compared mutation analysis by DNA sequencing and Amplification Refractory Mutation System™ (ARMS™) for their ability to detect mutations in clinical biopsy specimens. METHODS: We have evaluated five real-time ARMS assays: BRAF 1799T>A, [this includes V600E and V600K] and NRAS 182A>G [Q61R] and 181C>A [Q61K] in melanoma, EGFR 2573T>G [L858R], 2235-2249del15 [E746-A750del] in non-small-cell lung cancer, and compared the results to DNA sequencing of the mutation 'hot-spots' in these genes in formalin-fixed paraffin-embedded tumour (FF-PET) DNA. RESULTS: The ARMS assays maximised the number of samples that could be analysed when both the quality and quantity of DNA was low, and improved both the sensitivity and speed of analysis compared with sequencing. ARMS was more robust with fewer reaction failures compared with sequencing and was more sensitive as it was able to detect functional mutations that were not detected by DNA sequencing. DNA sequencing was able to detect a small number of lower frequency recurrent mutations across the exons screened that were not interrogated using the specific ARMS assays in these studies. CONCLUSIONS: ARMS was more sensitive and robust at detecting defined somatic mutations than DNA sequencing on clinical samples where the predominant sample type was FF-PET.
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Análisis Mutacional de ADN/métodos , ADN de Neoplasias/análisis , Neoplasias/genética , Reacción en Cadena de la Polimerasa/métodos , Carcinoma de Pulmón de Células no Pequeñas/genética , Ensayos Clínicos Fase II como Asunto , Ensayos Clínicos Fase III como Asunto , ADN de Neoplasias/genética , Humanos , Neoplasias Pulmonares/genética , Melanoma/genética , Neoplasias Cutáneas/genéticaRESUMEN
PURPOSE: To test the hypothesis that simultaneous, equipotent inhibition of epidermal growth factor receptor (EGFR; erbB1), erbB2 (human epidermal growth factor receptor 2), and erbB3 receptor signaling, using the novel small-molecule inhibitor AZD8931, will deliver broad antitumor activity in vitro and in vivo. EXPERIMENTAL DESIGN: A range of assays was used to model erbB family receptor signaling in homodimers and heterodimers, including in vitro evaluation of erbB kinase activity, erbB receptor phosphorylation, proliferation in cells, and in vivo testing in a human tumor xenograft panel, with ex vivo evaluation of erbB phosphorylation and downstream biomarkers. Gefitinib and lapatinib were used to compare the pharmacological profile of AZD8931 with other erbB family inhibitors. RESULTS: In vitro, AZD8931 showed equipotent, reversible inhibition of EGFR (IC(50), 4 nmol/L), erbB2 (IC(50), 3 nmol/L), and erbB3 (IC(50), 4 nmol/L) phosphorylation in cells. In proliferation assays, AZD8931 was significantly more potent than gefitinib or lapatinib in specific squamous cell carcinoma of the head and neck and non-small cell lung carcinoma cell lines. In vivo, AZD8931 inhibited xenograft growth in a range of models while significantly affecting EGFR, erbB2, and erbB3 phosphorylation and downstream signaling pathways, apoptosis, and proliferation. CONCLUSIONS: AZD8931 has a unique pharmacologic profile providing equipotent inhibition of EGFR, erbB2, and erbB3 signaling and showing greater antitumor activity than agents with a narrower spectrum of erbB receptor inhibition in specific preclinical models. AZD8931 provides the opportunity to investigate whether simultaneous inhibition of erbB receptor signaling could be of utility in the clinic, particularly in the majority of solid tumors that do not overexpress erbB2.
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Receptores ErbB/antagonistas & inhibidores , Quinazolinas/farmacología , Receptor ErbB-2/antagonistas & inhibidores , Receptor ErbB-3/antagonistas & inhibidores , Animales , Carcinoma de Células Escamosas/tratamiento farmacológico , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Gefitinib , Neoplasias de Cabeza y Cuello/tratamiento farmacológico , Humanos , Lapatinib , Ratones , Ratones Desnudos , Ratones SCID , Quinazolinas/agonistas , Transducción de Señal/efectos de los fármacos , Ensayos Antitumor por Modelo de XenoinjertoRESUMEN
PURPOSE In the phase III INTEREST trial, 1,466 pretreated patients with advanced non-small cell lung cancer (NSCLC) were randomly assigned to receive gefitinib or docetaxel. As a preplanned analysis, we prospectively analyzed available tumor biopsies to investigate the relationship between biomarkers and clinical outcomes. METHODS Biomarkers included epidermal growth factor receptor (EGFR) copy number by fluorescent in situ hybridization (374 assessable samples), EGFR protein expression by immunohistochemistry (n = 380), and EGFR (n = 297) and KRAS (n = 275) mutations. Results For all biomarker subgroups analyzed, survival was similar for gefitinib and docetaxel, with no statistically significant differences between treatments and no significant treatment by biomarker status interaction tests. EGFR mutation-positive patients had longer progression-free survival (PFS; hazard ratio [HR], 0.16; 95% CI, 0.05 to 0.49; P = .001) and higher objective response rate (ORR; 42.1% v 21.1%; P = .04), and patients with high EGFR copy number had higher ORR (13.0% v 7.4%; P = .04) with gefitinib versus docetaxel. CONCLUSION These biomarkers do not appear to be predictive factors for differential survival between gefitinib and docetaxel in this setting of previously treated patients; however, subsequent treatments may have influenced the survival results. For secondary end points of PFS and ORR, some advantages for gefitinib over docetaxel were seen in EGFR mutation-positive and high EGFR copy number patients. There was no statistically significant difference between gefitinib and docetaxel in biomarker-negative patients. This suggests gefitinib can provide similar overall survival to docetaxel in patients across a broad range of clinical subgroups and that EGFR biomarkers such as mutation status may additionally identify which patients are likely to gain greatest PFS and ORR benefit from gefitinib.
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Antineoplásicos/uso terapéutico , Biomarcadores de Tumor , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Receptores ErbB/antagonistas & inhibidores , Neoplasias Pulmonares/tratamiento farmacológico , Inhibidores de Proteínas Quinasas/uso terapéutico , Quinazolinas/uso terapéutico , Taxoides/uso terapéutico , Biomarcadores de Tumor/análisis , Biomarcadores de Tumor/genética , Biopsia , Carcinoma de Pulmón de Células no Pequeñas/enzimología , Carcinoma de Pulmón de Células no Pequeñas/genética , Carcinoma de Pulmón de Células no Pequeñas/mortalidad , Supervivencia sin Enfermedad , Docetaxel , Receptores ErbB/análisis , Receptores ErbB/genética , Femenino , Gefitinib , Dosificación de Gen , Humanos , Inmunohistoquímica , Hibridación Fluorescente in Situ , Modelos Logísticos , Neoplasias Pulmonares/enzimología , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/mortalidad , Masculino , Mutación , Oportunidad Relativa , Selección de Paciente , Valor Predictivo de las Pruebas , Modelos de Riesgos Proporcionales , Estudios Prospectivos , Proteínas Proto-Oncogénicas/genética , Proteínas Proto-Oncogénicas p21(ras) , Medición de Riesgo , Análisis de Supervivencia , Factores de Tiempo , Resultado del Tratamiento , Proteínas ras/genéticaRESUMEN
Two small-molecule epidermal growth factor receptor tyrosine kinase inhibitors, gefitinib and erlotinib, have been approved for the treatment of non-small-cell lung cancer. Here, we compare the pharmacology and pharmacokinetics of these agents, and reflect on how these properties may affect important clinical questions including the clinical efficacy, optimum dose, and whether there is a relationship between skin rash and clinical outcome for each of these agents. Gefitinib and erlotinib have similar mechanisms of action and pharmacological profiles; however, different molecular structures confer pharmacokinetic differences that may have important clinical implications. Although gefitinib 250 mg/day produces lower mean plasma concentrations and area under the plasma concentration versus time curve compared with erlotinib 150 mg/day, published data suggest that gefitinib significantly accumulates in tumour tissue. This difference may partly explain why it seems possible to achieve maximum clinical efficacy with gefitinib at doses significantly lower than its maximum tolerated dose and, hence, use of an optimal biological dose approach with this agent. We hypothesize that gefitinib is used and is effective at a dose below the maximum tolerated dose as it accumulates in tumour tissue, thus providing the concentration needed at its target to achieve effective epidermal growth factor receptor inhibition in the tumour while causing less skin toxicity than erlotinib; therefore, skin rash is not a useful predictive factor for efficacy with gefitinib.
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Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Receptores ErbB/antagonistas & inhibidores , Quinazolinas/farmacología , Quinazolinas/farmacocinética , Animales , Antineoplásicos/efectos adversos , Antineoplásicos/farmacocinética , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Clorhidrato de Erlotinib , Exantema/inducido químicamente , Gefitinib , Humanos , Quinazolinas/efectos adversos , Quinazolinas/uso terapéutico , Ensayos Clínicos Controlados Aleatorios como AsuntoRESUMEN
PURPOSE: To compare survival in patients with recurrent or metastatic squamous cell carcinoma of the head and neck (SCCHN) treated with gefitinib 250 or 500 mg/day or standard methotrexate. PATIENTS AND METHODS: Four hundred eighty-six patients with recurrent SCCHN were randomly assigned to oral gefitinib 250 mg/day, gefitinib 500 mg/day, or methotrexate 40 mg/m(2) intravenously weekly. Primary end point was overall survival, secondary end points were objective response rate (ORR), safety, symptom improvement, and quality of life (QOL). Exploratory end points included association of efficacy with epidermal growth factor receptor gene copy number and other biomarkers. RESULTS: Neither gefitinib 250 nor 500 mg/day improved overall survival compared with methotrexate (hazard ratio [HR], 1.22; 95% CI, 0.95 to 1.57; P = .12; and HR, 1.12; 95% CI, 0.87 to 1.43; P = .39, respectively). In the gefitinib 250 mg/day, 500 mg/day, and methotrexate groups, respectively, median overall survival was 5.6, 6.0, and 6.7 months; ORRs (Response Evaluation Criteria in Solid Tumors) were 2.7%, 7.6% and 3.9%, with no statistically significant difference between either gefitinib arm and methotrexate. No unexpected adverse events were observed, except for tumor hemorrhage-type events with gefitinib (8.9%, gefitinib 250 mg/day; 11.4%, gefitinib 500 mg/day; 1.9%, methotrexate). QOL improvement rates (Functional Assessment of Cancer Therapy-Head & Neck total score) were 13.4%, 18.0%, and 6.0% for gefitinib 250 mg/day, 500 mg/day, and methotrexate, respectively. CONCLUSION: In patients with recurrent or metastatic SCCHN, while responses with gefitinib were seen, neither gefitinib 250 nor 500 mg/day improved overall survival compared with methotrexate. With the exception of tumor hemorrhage-type events with gefitinib, the adverse event profiles were generally consistent with those previously observed.
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Antineoplásicos/administración & dosificación , Carcinoma de Células Escamosas/tratamiento farmacológico , Neoplasias de Cabeza y Cuello/tratamiento farmacológico , Metotrexato/administración & dosificación , Recurrencia Local de Neoplasia/tratamiento farmacológico , Quinazolinas/administración & dosificación , Administración Oral , Anciano , Carcinoma de Células Escamosas/secundario , Femenino , Gefitinib , Neoplasias de Cabeza y Cuello/secundario , Humanos , Infusiones Intravenosas , Masculino , Persona de Mediana Edad , Calidad de Vida , Análisis de Supervivencia , Resultado del TratamientoRESUMEN
Potential biomarkers were identified for in vitro sensitivity to the epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor gefitinib in head and neck cancer. Gefitinib sensitivity was determined in cell lines, followed by transcript profiling coupled with a novel pathway analysis approach. Eleven cell lines were highly sensitive to gefitinib (inhibitor concentration required to give 50% growth inhibition [GI(50)] < 1 microM), three had intermediate sensitivity (GI(50) 1-7 microM), and six were resistant (GI(50) > 7 microM); an exploratory principal component analysis revealed a separation between the genomic profiles of sensitive and resistant cell lines. Subsequently, a hypothesis-driven analysis of Affymetrix data (Affymetrix, Inc., Santa Clara, CA, USA) revealed higher mRNA levels for E-cadherin (CDH1); transforming growth factor, alpha (TGF-alpha); amphiregulin (AREG); FLJ22662; EGFR; p21-activated kinase 6 (PAK6); glutathione S-transferase Pi (GSTP1); and ATP-binding cassette, subfamily C, member 5 (ABCC5) in sensitive versus resistant cell lines. A hypothesis-free analysis identified 46 gene transcripts that were strongly differentiated, seven of which had a known association with EGFR and head and neck cancer (human EGF receptor 3 [HER3], TGF-alpha, CDH1, EGFR, keratin 16 [KRT16], fibroblast growth factor 2 [FGF2], and cortactin [CTTN]). Polymerase chain reaction (PCR) and enzyme-linked immunoabsorbant assay analysis confirmed Affymetrix data, and EGFR gene mutation, amplification, and genomic gain correlated strongly with gefitinib sensitivity. We identified biomarkers that predict for in vitro responsiveness to gefitinib, seven of which have known association with EGFR and head and neck cancer. These in vitro predictive biomarkers may have potential utility in the clinic and warrant further investigation.
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Antineoplásicos/farmacología , Biomarcadores de Tumor/análisis , Resistencia a Antineoplásicos/efectos de los fármacos , Neoplasias de Cabeza y Cuello/genética , Quinazolinas/farmacología , Antineoplásicos/uso terapéutico , Biomarcadores de Tumor/genética , Línea Celular Tumoral , Análisis Mutacional de ADN , Resistencia a Antineoplásicos/genética , Ensayos de Selección de Medicamentos Antitumorales , Ensayo de Inmunoadsorción Enzimática , Gefitinib , Dosificación de Gen/genética , Perfilación de la Expresión Génica , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Genoma Humano/genética , Humanos , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , Quinazolinas/uso terapéutico , ARN Mensajero/genética , ARN Mensajero/metabolismoRESUMEN
PURPOSE: This phase II, open-label, parallel-group study compared gefitinib with vinorelbine in chemotherapy-naïve elderly patients with advanced non-small-cell lung cancer (NSCLC). METHODS: Chemotherapy-naïve patients (age >or= 70 years) were randomly assigned to gefitinib (250 mg/d orally) or vinorelbine (30 mg/m(2) infusion on days 1 and 8 of a 21-day cycle). The primary end point was progression-free survival (PFS). Secondary end points were overall survival (OS), objective response rate (ORR), quality of life (QOL), pulmonary symptom improvement (PSI), and tolerability. Exploratory end points included epidermal growth factor receptor (EGFR) gene copy number by fluorescent in situ hybridization (FISH). RESULTS: Patients were randomly assigned to gefitinib (n = 97) or to vinorelbine (n = 99). Hazard ratios (HR; gefitinib v vinorelbine) were 1.19 (95% CI, 0.85 to 1.65) for PFS and 0.98 (95% CI, 0.66 to 1.47) for OS. ORR and disease control rates were 3.1% (95% CI, 0.6 to 8.8) and 43.3% (for gefitinib) and 5.1% (95% CI, 1.7 to 11.4) and 53.5% (for vinorelbine), respectively. Overall QOL improvement and PSI rates were 24.3% and 36.6% (for gefitinib) and 10.9% and 31.0% (for vinorelbine), respectively. In the 54 patients who were EGFR FISH-positive, HRs were 3.13 (95% CI, 1.45 to 6.76) for PFS and 2.88 (95% CI, 1.21 to 6.83) for OS. There were fewer treatment-related grade 3 to 5 adverse events with gefitinib (12.8%) than with vinorelbine (41.7%). CONCLUSION: There was no statistical difference between gefitinib and vinorelbine in efficacy in chemotherapy-naïve, unselected elderly patients with advanced NSCLC, but there was better tolerability with gefitinib. Individuals who were EGFR FISH-positive benefited more from vinorelbine than from gefitinib; this unexpected finding requires further study.
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Antineoplásicos/uso terapéutico , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Neoplasias Pulmonares/tratamiento farmacológico , Quinazolinas/uso terapéutico , Vinblastina/análogos & derivados , Anciano , Anciano de 80 o más Años , Carcinoma de Pulmón de Células no Pequeñas/mortalidad , Progresión de la Enfermedad , Femenino , Gefitinib , Humanos , Neoplasias Pulmonares/mortalidad , Masculino , Análisis de Supervivencia , Vinblastina/uso terapéutico , VinorelbinaRESUMEN
BACKGROUND: The ISEL (Iressa Survival Evaluation in Lung Cancer) clinical trial evaluated the efficacy of gefitinib versus placebo in pretreated nonsmall-cell lung cancer patients. Two different antibodies, scoring systems, and cutoff points of epidermal growth factor receptor (EGFR) protein expression were compared to predict response and survival of enrolled patients. METHODS: EGFR expression was assessed in tumor samples by immunohistochemistry using the Dako EGFR pharmDx kit (scoring percent of tumor cells with positive staining) and Zymed monoclonal antibody clone 31G7 (scoring staining index derived from proportion of positive cells times staining intensity). RESULTS: Data for EGFR expression were available for 379 patients for Dako and 357 patients for Zymed antibody (22% and 21%, respectively, of trial population). Objective response rates in gefitinib-treated EGFR-positive patients defined with various cutpoints with Dako antibody varied between 8% and 12%, and with Zymed antibody between 10% and 13%. Lower cutoff points with Dako antibody provided the best discrimination between EGFR-positive and EGFR-negative patients for survival hazard ratios comparing gefitinib to placebo, with a significant treatment/cutoff point interaction for 10% cutoff point (P = .049). A similar but less apparent trend was noted for Zymed antibody, although the discrimination between hazard ratios was not significant for any cutoff point analyzed. CONCLUSIONS: Assessment with the Dako PharmDx kit and percentage of cells with positive staining may provide more accurate prediction of differential effect on survival with gefitinib than assessment with Zymed antibody and staining index. Using higher cutpoints to define positivity does not improve test discrimination.
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Anticuerpos Monoclonales , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Receptores ErbB/análisis , Inmunohistoquímica/métodos , Neoplasias Pulmonares/tratamiento farmacológico , Quinazolinas/uso terapéutico , Biomarcadores de Tumor/análisis , Femenino , Gefitinib , Humanos , Masculino , Placebos , Valor Predictivo de las PruebasRESUMEN
Inhibition of the epidermal growth factor receptor as a target for cancer chemotherapy has proven to be an effective treatment in both preclinical and clinical settings. Recent work has indicated that the presence of somatic mutations in the tyrosine kinase domain of the epidermal growth factor receptor is a major determinant of the response to the tyrosine kinase inhibitors gefitinib and erlotinib. However, this is not the full story, and further work is needed to identify the factors underlying the response in those who do not carry mutations. Mechanisms of innate and acquired resistance to epidermal growth factor receptor inhibitors are also topics under investigation. Crosstalk between the epidermal growth factor receptor and other growth factor receptors involved in tumorigenesis has been implicated, along with downstream signalling molecules such as Ras, Braf and PTEN. A full understanding of these mechanistic aspects could lead to the identification of useful combinations of inhibitors of novel targets.