No abstract

Large-scale screening of patients with lung cancer for EGFR mutations is feasible and can have a role in decisions about treatment.

Purpose: Advanced non-small-cell lung cancer (NSCLC) patients harboring epidermal growth factor receptor (EGFR) mutations (deletion in exon 19 or L858R) show an impressive progression-free survival of 14 months when treated with erlotinib. However, the presence of EGFR mutations can only imperfectly predict outcome. We hypothesized that progression-free survival could be influenced both by the pretreatment EGFR T790M mutation and by components of DNA repair pathways.Experimental Design: We assessed the T790M mutation in pretreatment diagnostic specimens from 129 erlotinib-treated advanced NSCLC patients with EGFR mutations. The expression of eight genes and two proteins involved in DNA repair and four receptor tyrosine kinases was also examined.Results: The EGFR T790M mutation was observed in 45 of 129 patients (35%). Progression-free survival was 12 months in patients with and 18 months in patients without the T790M mutation (P ¼ 0.05). Progression-free survival was 27 months in patients with low BRCA1 mRNA levels, 18 months in those with intermediate levels, and 10 months in those with high levels (P ¼ 0.02). In the multivariate analysis, the presence of the T790M mutation (HR, 4.35; P ¼ 0.001), intermediate BRCA1 levels (HR, 8.19; P < 0.0001), and high BRCA1 levels (HR, 8.46; P < 0.0001) emerged as markers of shorter progression-free survival.Conclusions: Low BRCA1 levels neutralized the negative effect of the T790M mutation and were associated with longer progression-free survival to erlotinib. We advocate baseline assessment of the T790M mutation and BRCA1 expression to predict outcome and provide alternative individualized treatment to patients based on T790M mutations and BRCA1 expression.

Lung cancer is the most common cancer, with dismal outcome. Treatment approaches, including cisplatin-based chemotherapy and surgery, are currently based on the clinical classification of the tumor, without genetic assessment for predicting differential chemosensitivity. BRCA1 plays a central role in DNA repair, and decreased BRCA1 mRNA expression in the human breast cancer HCC1937 cell line caused cisplatin hypersensitivity, but the relation between BRCA1 and survival in lung cancer patients has never been examined. We used real-time quantitative polymerase chain reaction to determine BRCA1 mRNA levels in 55 surgically resected tumors of non-small-cell lung cancer patients who had received neoadjuvant gemcitabine/cisplatin chemotherapy, and divided the gene expression values into quartiles. When results were correlated with outcome, two cut-offs were observed; patients with levels <0.61 had better outcome, and those >2.45 had poorer outcome. Median survival was not reached for the 15 patients in the bottom quartile, whereas for the 28 in the two middle quartiles, it was 37.8 months (95% CI, 10.6-65), and for the 12 patients in the top quartile, it was 12.7 months (95% CI, 0.28-28.8) (P=0.01). Moreover, when patients were stratified by pathologic stage, those in the bottom quartile had a decreased risk of death (HR=0.206; 95% CI, 0.05-0.83; P=0.026) compared with those in the top quartile, and those in the two middle quartiles also had a decreased risk of death (HR=0.294; 95% CI, 0.10-0.83; P=0.020) compared with those in the top quartile. BRCA1 expression is potentially an important tool for use in cancer management and should be assessed for predicting differential chemosensitivity and tailoring chemotherapy in lung cancer.

Purpose: Activating mutations in the tyrosine kinase domain of the epidermal growth factor receptor (EGFR) confer a strong sensitivity to gefitinib, a selective tyrosine kinase inhibitor of EGFR. Experimental Design:We examined EGFR mutations at exons18,19, and 21in tumor tissue from 68 gefitinib-treated, chemorefractory, advanced non^small cell lung cancer patients from the United States, Europe, and Asia and in a highly gefitinib-sensitive non^small cell lung cancer cell line and correlated their presence with response and survival. In addition, in a subgroup of 28 patients for whom the remaining tumor tissue was available, we examined the relationship among EGFR mutations, CA repeats in intron 1 of EGFR, EGFR and caveolin-1 mRNA levels, and increased EGFR gene copy numbers. Results: Seventeen patients had EGFR mutations, all of which were in lung adenocarcinomas. Radiographic response was observed in 16 of 17 (94.1%) patients harboring EGFR mutations, in contrast with 6 of 51 (12.6%) with wild-type EGFR (P < 0.0001). Probability of response increased significantly innever smokers, patients receiving a greater number of prior chemotherapy regimens, Asians, and younger patients. Median survival was not reached for patients with EGFR mutations and was 9.9 months for those with wild-type EGFR (P = 0.001). EGFR mutations tended to be associated with increased numbers of CA repeats andincreased EGFR gene copy numbers but not with EGFR and caveolin-1mRNA overexpression (P = not significant). Conclusions:The presence of EGFR mutations is a major determinant of gefitinib response, and targeting EGFR should be considered in preference to chemotherapy as first-line treatment in lung adenocarcinomas that have demonstrable EGFR mutations.

clinicaltrials.gov Identifier: NCT00446225.

Median survival of patients with brain metastases from nonsmall cell lung cancer (NSCLC) is poor and more effective treatments are urgently needed. We have evaluated the efficacy of erlotinib in this setting and its association with activating mutations in the epidermal growth factor receptor (EGFR) gene.We retrospectively identified patients with NSCLC and brain metastases treated with erlotinib. EGFR mutations in exons 19 and 21 were analysed by direct sequencing. Efficacy and tolerability were compared according to EGFR mutational status.69 NSCLC patients with brain metastases were identified, 17 of whom harboured EGFR mutations. Objective response rate in patients with EGFR mutations was 82.4%; no responses were observed in unselected patients (p,0.001). Median (95% CI) time to progression within the brain for patients harbouring EGFR mutations was 11.7 (7.9-15.5) months, compared to 5.8 (5.2-6.4) months for control patients whose EGFR mutational status had not been assessed (p,0.05). Overall survival was 12.9 (6.2-19.7) months and 3.1 (2.5-3.9) months (p,0.001), respectively. The toxicity of erlotinib was as expected and no differences between cohorts were observed.Erlotinib is active in brain metastases from NSCLC; this clinical benefit is related to the presence of activating mutations in exons 19 or 21 of the EGFR gene.

GCA patients with a strong systemic inflammatory response, who have been previously shown to be more resistant to corticosteroid therapy, have elevated tissue expression of proinflammatory cytokines IL-1beta, TNFalpha and IL-6. High production of TNFalpha is associated with longer corticosteroid requirements.