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A study of patients with advanced non-squamous non-small cell lung cancer (NSCLC) evaluated epidermal growth factor receptor (EGFR) mutation status and serum hepatocyte growth factor (HGF) for their associations with response to gefitinib therapy and prognostic impact. An enzyme-linked immunosorbent assay was used to determine levels of HGF in serum from 96 Japanese patients with advanced non-squamous NSCLC. The peptic nucleic acid-locked nucleic acid clamp method was used to determine their EGFR somatic mutation status. We evaluated the relationship between each independent clinicopathological variable and the response to gefitinib therapy and risk factors associated with prognosis. HGF-positive serum status (hazard ratio, 1.536; 95% confidence interval, 1.042-2.400; P = 0.0295) had a significant and independent negative effect on progression-free survival among patients with wild-type EGFR. We demonstrate that having HGF-positive serum is predictive of a negative response to gefitinib therapy in patients with advanced NSCLC who harbor wild-type EGFR.

Background: Non-small cell lung cancer (NSCLC) harboring common epidermal growth factor receptor (EGFR) gene mutations (exon 19 deletion or exon 21 L858R) respond to EGFR tyrosine kinase inhibitors (EGFR-TKIs). The secondary T790 M mutation in exon 20 of the EGFR gene is the most common type of acquired resistance mutation. Several reports have also shown that other secondary mutations (L747S, D761Y and T854A), while uncommon, can induce acquired resistance to first-generation EGFR-TKIs. However, little is known about the anticancer activities of second- or third-generation EGFR-TKIs. Methods: Uncommon secondary mutations were introduced into Ba/F3 cells along with the sensitive EGFR L858R mutation (Ba/F3-L858R/L747S, Ba/F3-L858R/D761Y, and Ba/F3-L858R/T854A), and the sensitivities to various EGFR-TKIs were then investigated. Results: Both the Ba/F3-L858R/L747S and Ba/F3-L858R/D761Y cell lines exhibited weak resistances to first-generation reversible EGFR-TKIs, while the Ba/F3-L858R/T854A cell line exhibited a strong resistance. In contrast, irreversible EGFR-TKIs, especially third-generation EGFR-TKIs, were capable of overcoming these resistances. Western blot analyses demonstrated that gefitinib (first-generation) inhibited the phosphorylation of EGFR to a lesser extent in cells with these secondary mutations than in cells with the sensitive L858R mutation alone. In contrast, afatinib and osimertinib (second- and thirdgeneration) inhibited the phosphorylation of EGFR in cells with these secondary mutations to a similar extent as that seen in cells with the sensitive L858R mutation alone. Conclusions: Our experimental findings suggest that irreversible EGFR-TKIs, especially third-generation EGFR-TKIs, can be effective against uncommon secondary mutations and that switching to third-generation EGFR-TKIs could be a promising treatment strategy for patients with acquired resistance because of these uncommon secondary mutations. [ABSTRACT FROM AUTHOR]

Purpose: Recent reports indicate that refractory central nervous system (CNS) metastases of non-small cell lung cancer (NSCLC) are improved by high-dose gefitinib or erlotinib administration. We describe a Japanese woman with NSCLC and CNS metastases who was resistant to 75 mg daily erlotinib, but the metastases were improved by 150 mg daily erlotinib. We investigated the plasma and CSF concentrations of erlotinib at each dose as well as the correlation between the plasma and CSF concentrations of erlotinib. Methods: Including this patient, we administered 150 mg erlotinib daily to nine NSCLC patients with CNS metastases and measured the plasma and CSF concentrations just before administration on day 8. The concentrations were determined using high-performance liquid chromatography with ultraviolet detection. Results: The plasma and CSF concentrations of erlotinib at a dose of 75 mg were 433 and 14 nM, respectively. The plasma and CSF concentrations of erlotinib at a dose of 150 mg were increased to 1,117 and 44 nM, respectively. The mean ± standard deviation of CSF concentrations and penetration rates were 106 ± 59 nM and 4.5 ± 1.5%, respectively. There was a good correlation ( R = 0.84) between plasma and CSF concentrations ( P = 0.0005). Conclusions: This study indicates that CSF concentrations of erlotinib depend on its plasma concentration. As seen in this patient, high CSF concentrations of erlotinib can be achieved by high-dose administration, and this finding suggests the efficacy of high-dose administration, especially to refractory CNS metastases of NSCLC patients. [ABSTRACT FROM AUTHOR]

Purpose: We examined patients with advanced nonsquamous, non-small cell lung cancer (NSCLC) to evaluate epidermal growth factor receptor (EGFR) mutation status and serum C-reactive protein (CRP) for their associations with response to gefitinib therapy and for prognostic impacts. Methods: Serum levels of CRP from 79 Japanese patients with advanced nonsquamous NSCLC were measured before the start of gefitinib. We used the peptic nucleic acid-locked nucleic acid clamp method to determine their EGFR somatic mutation status. We evaluated the relationship between each independent clinicopathological variable and the response to gefitinib therapy and the risk factors associated with prognosis. Results: Having CRP-positive serum and having wild-type EGFR were both independent negative predictive factors for the response to gefitinib treatment by multivariate logistic regression model analysis. Having CRP-positive serum and having wild-type EGFR were significant independent negative prognostic factors for survival based on multivariate analysis. Conclusions: Having CRP-positive serum predicted a lack of response to gefitinib therapy independent of EGFR mutational status. Both CRP-positive serum and wild-type EGFR were independent poor prognostic factors in patients with nonsquamous NSCLC who received gefitinib therapy. Copyright © 2011 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

BACKGROUND: Although the association of multiple pulmonary metastases, and particularly miliary metastases, with response to gefitinib treatment in patients with nonsmall cell lung cancer has been reported, the association of miliary pulmonary metastases with epidermal growth factor receptor gene (EGFR) mutations remains unclear. METHODS: The authors retrospectively investigated the association of diffuse, random pulmonary metastases in patients with lung adenocarcinoma. The study included 163 Japanese patients who had unresectable, advanced lung adenocarcinoma diagnosed between April 2003 and March 2010. Computed tomography scans that were obtained at the time of diagnosis were analyzed by 2 investigators. For the purposes of this study, diffuse, random pulmonary metastases were defined as multiple nodules (n = 50; ≤3 cm in greatest dimension) distributed diffusely and randomly throughout the lungs. RESULTS: Of 163 patients, 55 had pulmonary metastases, and EGFR mutations were detected in 22 of those 55 patients. The mutations were identified preferentially among women (P = .15) and were identified significantly among patients who had a smoking history of <10 pack-years (P = .0057). Diffuse, random pulmonary metastases were identified in 11 of 22 patients who had EGFR mutations and in 4 of 33 patients who had the wildtype EGFR (P = .0043). On the basis of multivariate analyses, EGFR mutations were associated independently with a smoking history of <10 pack-years (P = .026) and with diffuse, random pulmonary metastases (P = .012). CONCLUSIONS: When patients with lung adenocarcinomas who had EGFR mutations developed pulmonary metastases, they tended to be diffuse and random, including military metastases. However, such metastases were much less common in patients who had lung adenocarcinomas with wild-type EGFR. Cancer 2011;117:819-25. [ABSTRACT FROM AUTHOR]