Akihito Kubo

Randomized Phase III Trial of Erlotinib Versus Docetaxel As Second- or Third-Line Therapy in Patients With Advanced Non–Small-Cell Lung Cancer: Docetaxel and Erlotinib Lung Cancer Trial (DELTA)

PURPOSE To investigate the efficacy of erlotinib versus docetaxel in previously treated patients with advanced non-small-cell lung cancer (NSCLC) in an epidermal growth factor receptor (EGFR) -unselected patient population. PATIENTS AND METHODS The primary end point was progression-free survival (PFS). Secondary end points included overall survival (OS), response rate, safety, and analyses on EGFR wild-type tumors. Patients with stage IIIB or IV NSCLC, previous treatment with one or two chemotherapy regimens, evaluable or measurable disease, and performance status of 0 to 2 were eligible. RESULTS From August 2009 to July 2012, 150 and 151 patients were randomly assigned to erlotinib (150 mg daily) and docetaxel (60 mg/m(2) every 3 weeks), respectively. EGFR wild-type NSCLC was present in 109 and 90 patients in the erlotinib and docetaxel groups, respectively. Median PFS for erlotinib versus docetaxel was 2.0 v 3.2 months (hazard ratio [HR], 1.22; 95% CI, 0.97 to 1.55; P = .09), and median OS was 14.8 v 12.2 months (HR, 0.91; 95% CI, 0.68 to 1.22; P = .53), respectively. In a subset analysis of EGFR wild-type tumors, PFS for erlotinib versus docetaxel was 1.3 v 2.9 months (HR, 1.45; 95% CI, 1.09 to 1.94; P = .01), and OS was 9.0 v 10.1 months (HR, 0.98; 95% CI, 0.69 to 1.39; P = .91), respectively. CONCLUSION Erlotinib failed to show an improvement in PFS or OS compared with docetaxel in an EGFR-unselected patient population.

Performance Status and Smoking Status Are Independent Favorable Prognostic Factors for Survival in Non-small Cell Lung Cancer: A Comprehensive Analysis of 26,957 Patients with NSCLC

Background: Performance status (PS) is an important factor in determining survival outcome in non-small cell lung cancer (NSCLC) but is generally confounded by stage, age, gender, and smoking status. We investigated the prognostic significance of PS taking into account these important factors. Methods: Retrospective analysis of registry database of the National Hospital Study Group for Lung Cancer (NHSGLC) between1990 and 2005. Univariate analysis was performed using Kaplan-Meier method. Multivariate analysis was performed using Cox proportional hazards model to identify independent prognostic factors. Results: A total of 26,957 patients with NSCLC were analyzed of which 12,613 patients (46.8%) had World Health Organization (WHO) PS = 0, 8,137 patients were never smokers (30.2%), and most of them were females (72.7%). The majority of PS = 0 patients presented with stage I disease (56.9%). Patients with PS = 0 constituted the group with the highest proportion of never smokers (36.7%). There was a significant difference in the median overall survival (OS) between patients with PS = 0 and PS = 1 (51.5 months versus 15.4 months, respectively; p < 0.0001) and among patients with various PS within individual American Joint Committee on Cancer stage (all p values <0.0001). Never smokers had significantly improved median OS than ever smokers (30.0 months versus 19.0 months, respectively; p < 0.0001). Multivariate analysis demonstrated good PS, never smoker (versus ever smoker; hazard ratio = 0.935, 95% confidence interval: 0.884–0.990; p = 0.0205), early stage, female gender, squamous cell carcinoma histology, and treatment were all as independent favorable prognostic factors. Conclusions: PS and smoking status are independent prognostic factors for OS in NSCLC.

Ultra-Sensitive Detection of the Pretreatment EGFR T790M Mutation in Non–Small Cell Lung Cancer Patients with an EGFR-Activating Mutation Using Droplet Digital PCR

Purpose: The resistance to the EGFR tyrosine kinase inhibitors (TKI) is a major concern in non–small cell lung cancer (NSCLC) treatment. T790M mutation in EGFR accounts for nearly 50% of the acquired resistance to EGFR-TKIs. Earlier studies suggested that T790M mutation was also detected in TKI-naïve NSCLCs in a small cohort. Here, we use an ultra-sensitive droplet digital PCR (ddPCR) technique to address the incidence and clinical significance of pretreatment T790M in a larger cohort. Experimental Design: ddPCR was established as follows: wild-type or T790M mutation-containing DNA fragments were cloned into plasmids. Candidate threshold was identified using wild-type plasmid, normal human genomic DNA, and human A549 cell line DNA, which expresses wild type. Surgically resected tumor tissues from 373 NSCLC patients with EGFR-activating mutations were then examined for the presence of T790M using ddPCR. Results: Our data revealed a linear performance for this ddPCR method (R2 = 0.998) with an analytical sensitivity of approximately 0.001%. The overall incidence of the pretreatment T790M mutation was 79.9% (298/373), and the frequency ranged from 0.009% to 26.9%. The T790M mutation was detected more frequently in patients with a larger tumor size (P = 0.019) and those with common EGFR-activating mutations (P = 0.022), as compared with the others. Conclusions: The ultra-sensitive ddPCR assay revealed that pretreatment T790M was found in the majority of NSCLC patients with EGFR-activating mutations. ddPCR should be utilized for detailed assessment of the impact of the low frequency pretreatment T790M mutation on treatment with EGFR-TKIs. Clin Cancer Res; 21(15); 3552–60. ©2015 AACR.

Epidermal Growth Factor Receptor Tyrosine Kinase Inhibitors Beyond Progressive Disease: A Retrospective Analysis for Japanese Patients with Activating EGFR Mutations

Introduction: It is not determined whether the continuous use of epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKI) is reasonable for patients with activating EGFR mutations, who have progressed with the drug. Methods: We retrospectively analyzed the data from 2002 to 2010 of consecutive patients who had advanced non–small-cell lung cancer (NSCLC) harboring activating EGFR mutations and showed radiological disease progression after EGFR-TKI treatment as the first-line or second-line setting. We classified them into two groups: continuous EGFR-TKI and switching to chemotherapy, and compared the clinical outcomes. Multivariate analysis for survival was performed including age, sex, Eastern Cooperative Oncology Group performance status (0–1/ 2–4), brain metastasis, EGFR mutations (deletions in exon 19 versus L858R), continuous EGFR-TKI (yes/no), and initiation of EGFR-TKI (first versus second). Results: A total of 551 NSCLC patients were screened for EGFR mutations in the period, and 186 patients had activating EGFR mutations. To explore the potential use of EGFR-TKI beyond progressive disease (PD), 64 patients were selected and analyzed. There were 13 men and 51 women, and median age was 65.5 years (range, 42–86). Among them, 31 patients had deletions in exon 19, and 33 had point mutation of L858R in exon 21. Thirty-nine patients were continuing EGFR-TKI beyond PD; 25 patients were switched to cytotoxic chemotherapy alone. The median overall survival was 32.2 months in the patients continuing EGFR-TKI, and 23.0 months in the patients switching to chemotherapy, presenting a significant difference between the two groups (p = 0.005). Cox analysis showed that continuous EGFR-TKI after PD (hazards ratio 0.42, 95% confidence interval: 0.21–0.83, p = 0.013) was associated with improved survival. Conclusion: Continuous use of EGFR-TKI beyond PD may prolong overall survival compared with switching to cytotoxic chemotherapy in patients with activating EGFR mutations. A prospective study will be needed to confirm our results.

Gender, Histology, and Time of Diagnosis Are Important Factors for Prognosis: Analysis of 1499 Never-Smokers with Advanced Non-small Cell Lung Cancer in Japan

Background: There has been a growing interest in lung cancer in never-smokers. Methods: Utilizing a database from the National Hospital Study Group for Lung Cancer, information for never-smokers and ever-smokers with advanced non-small cell lung cancer was obtained from 1990 to 2005, including clinicopathologic characteristics, chemotherapy response, and survival data. Time of diagnosis was classified into two periods: 1990–1999 and 2000–2005. Multivariate analysis was performed using the Cox regression and logistic regression method, including gender, age, performance status, histology, stage, and period of diagnosis. Results: There were 1499 never-smokers and 3455 ever-smokers with advanced stage IIIB and IV diseases who received cytotoxic chemotherapy. Never-smokers generally included more females, were younger, with better performance status and more adenocarcinoma diagnosed (p < 0.0001 for all). Smoking status was a significant prognostic factor (never-smoker versus ever-smoker; hazard ratio [HR] = 0.880, 95% confidence interval [CI]: 0.797–0.970; p = 0.0105). In separate multivariate analysis for never-smokers and ever-smokers, female gender and better performance status (p < 0.0001 for both) were both favorable prognostic factors. However, adenocarcinoma histology (versus squamous cell carcinoma; HR = 0.790, 95% CI: 0.630–0.990; p = 0.0403) and the period after 2000 (versus before 2000; HR = 0.846, 95% CI: 0.731–0.980; p = 0.0254) were significant only in the never-smokers, and younger age (HR = 1.007, 95% CI: 1.003–1.011; p = 0.0010) was significant only in the ever-smokers. In an exploratory analysis, different profiles were observed in predictive factors for chemotherapy response between the two groups. Conclusions: Never-smokers with non-small cell lung cancer lived longer than ever-smokers. Gender, histology, and time of diagnosis are important factors for prognosis in these patients.

Is Consolidation Chemotherapy after Concurrent Chemo-Radiotherapy Beneficial for Patients with Locally Advanced Non–Small-Cell Lung Cancer?: A Pooled Analysis of the Literature

Introduction: The purpose of this study was to evaluate whether consolidation chemotherapy (CCT) after concurrent chemo-radiotherapy is beneficial for patients with locally advanced non–small-cell lung cancer (LA-NSCLC). Methods: We systematically searched PubMed for phase II/III trials published before December 31, 2011, examining survival of LA-NSCLC treated with concurrent chemo-radiotherapy. Median overall survival and other study characteristics were collected from each study and pooled. We extracted log-transformed hazards and standard errors under the assumption that survival follows an exponential distribution, and computed a pooled median overall survival and a 95% confidence interval (CI) using random-effects model. Collected trial arms were categorized as having CCT or not having it, CCT+ and CCT−, respectively. Results: Forty-one studies were identified including seven phase III studies and 34 phase II studies with 45 arms (CCT+: 25; CCT−: 20). Clinical data were comparable for clinical stage, performance status, cancer histology, sex, and median age between the two groups. There was no statistical difference in pooled mOS between CCT+ (19.0 month; 95% CI, 17.3−21.0) and CCT− (17.9 month; 95% CI, 16.1−19.9). Predicted hazard ratio of CCT+ to CCT− was 0.94 (95% CI, 0.81−1.09; p = 0.40). There were no differences between the two groups with regard to grade 3−5 toxicities in pneumonitis, esophagitis, and neutropenia. These models estimated that addition of CCT could not lead to significant survival prolongation or risk reduction in death for LA-NSCLC patients. Conclusion: The pooled analysis based on a publication basis failed to provide evidence that CCT yields significant survival benefit for LA-NSCLC.

Response Rate Is Associated with Prolonged Survival in Patients with Advanced Non-small Cell Lung Cancer Treated with Gefitinib or Erlotinib

Introduction: Gaining a higher response rate (RR) has usually been determined as a primary end point in phase II trials evaluating the efficacy of new molecular targeted drugs. However, a relationship between clinical response and survival benefit has not been well studied in the patients treated with molecular targeted agents. Methods: Prospective trials of epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs) monotherapy in non-small cell lung cancer were extracted from MEDLINE, EMBASE, and the annual meetings in 2007 of the American Society of Clinical Oncology, European Cancer Conference, and World Conference on Lung Cancer. Correlation between clinical response and survival was examined using linear regression analysis. We also tried to compare the significance of RR as surrogate markers for survival with that of disease control rate (DCR) by calculating the area under their receiver operating characteristic (ROC) curves. Results: We identified 24 phase II trials and 4 phase III trials with a total of 6171 patients and 30 treatment arms, including 22 arms for the gefitinib group and 8 arms for the erlotinib group. Both RR and DCR strongly correlated with median survival time (MST; p < 0.0001 and p = 0.003, respectively). In an ROC analysis, the area under the ROC curve predicting MST prolongation by RR was 0.918, which was higher than the area under the ROC curve by DCR. Conclusions: We found a significant relationship between RR and MST in clinical trials with EGFR-TKIs. RR could be an independent surrogate marker for MST in the current response criteria in the clinical trials of EGFR-TKIs.

Ethnic Difference in Hematological Toxicity in Patients with Non-small Cell Lung Cancer Treated with Chemotherapy: A Pooled Analysis on Asian versus Non-Asian in Phase II and III Clinical Trials

Introduction: There are a large number of global clinical trials ongoing for patients with non-small cell lung cancer (NSCLC). Ethnic difference in toxicity has not been adequately studied. Methods: We performed a systematic search in PubMed for randomized phase II and III trials of NSCLC from January 2000 to December 2009, examining ethnic difference in hematological toxicity due to cytotoxic chemotherapy. Ethnicity was classified into Asian and non-Asian. We chose three treatment regimens used for NSCLC globally: cisplatin plus gemcitabine (CG), cisplatin plus vinorelbine (CV), and carboplatin plus paclitaxel (CP). We applied sensitivity analysis to examine unreported ethnic differences in hematological toxicities by changing the percentage of Asian patients from 0 to 18% in trials reported from the United States and Europe. Results: We identified 12 phase II trials and 38 phase III trials of NSCLC with a total of 11,271 patients. Among these, 14 trials had reported ethnic origins. Grade 3/4 toxicities were more frequently observed in the Asian studies. On the basis of sensitivity analysis, odds ratio of grade 3/4 neutropenia was significantly higher in Asian patients than non-Asian, when treated with CG (OR = 1.55–3.45, p < 0.001), CV (OR = 2.99–4.43, p < 0.001), and CP (OR = 4.79–6.22, p < 0.001). Grade 3/4 anemia was also significantly higher in Asians with CG (OR = 3.10–3.27, p < 0.001), CV (OR = 1.99–2.43, p < 0.001), and CP (OR = 1.34–1.52, p < 0.001–0.004). However, no significant difference was observed in thrombocytopenia with CG (OR = 0.66–2.04, p < 0.001–1.000), CV (OR = 0.42–0.57, p = 0.097–0.323), or CP (OR = 1.21–1.39, p = 0.114–0.152). Conclusions: Severe hematological toxicity was frequently observed in Asian patients compared with non-Asian (mostly whites) in the treatment of chemotherapy for NSCLC.

Phase II Study of Combination Therapy with S-1 and Irinotecan for Advanced Non–Small Cell Lung Cancer: West Japan Thoracic Oncology Group 3505

Purpose: To evaluate the efficacy and toxicity of combination therapy with the oral fluoropyrimidine formulation S-1 and irinotecan for patients with advanced NSCLC. Experimental Design: Chemotherapy-naive patients with advanced NSCLC were treated with i.v. irinotecan (150 mg/m2) on day 1 and with oral S-1 (80 mg/m2) on days 1 to 14 every 3 weeks. Results: Fifty-six patients (median age, 63 years; range, 40-74 years) received a total of 286 treatment cycles (median, 5; range, 1-15). No complete responses and 16 partial responses were observed, giving an overall response rate of 28.6% [95% confidence interval (95% CI), 17.3-42.2%]. Twenty-four patients (42.9%) had stable disease and 12 patients (21.4%) had progressive disease as the best response. The overall disease control rate (complete response + partial response + stable disease) was thus 71.4% (95% CI, 57.8-82.7%). Median progression-free survival was 4.9 months (95% CI, 4.0-6.4 months), whereas median overall survival was 15 months. Hematologic toxicities of grade 3 or 4 included neutropenia (25%), thrombocytopenia (3.6%), and anemia (3.6%), with febrile neutropenia being observed in four patients (7.1%). The most common nonhematologic toxicities of grade 3 or 4 included anorexia (14.3%), fatigue (8.9%), and diarrhea (8.9%). There were no deaths attributed to treatment. Conclusions: The combination of S-1 and irinotecan is a potential alternative option with a favorable toxicity profile for the treatment of advanced NSCLC. This nonplatinum regimen warrants further evaluation in randomized trials.

Long Exposure of Environmental Tobacco Smoke Associated with Activating EGFR Mutations in Never-Smokers with Non–Small Cell Lung Cancer

Purpose: To examine an association between environmental tobacco smoke (ETS) and activating epidermal growth factor receptor (EGFR) mutations in never-smokers with non–small cell lung cancer (NSCLC). Experimental Design: A total of 126 never-smokers with NSCLC were prospectively included in this study. Detailed ETS information was obtained through a standardized questionnaire including exposure period, place, and duration. Cumulative dose of ETS (CETS) was evaluated as a sum of the number of the exposure years at home and/or workplace. EGFR and K-ras mutations were determined using real-time PCR amplification. Results: A total of 124 patients (98.4%) had ETS exposure with median CETS of 50 years (range: 0–118). Activating EGFR mutations were detected in 62.7% of the 126 patients and K-ras in 2 of 114 patients. The incidence of activating EGFR mutations was significantly higher in females than in males (67.6% vs. 26.7%; P = 0.002), and increased in quintile groups separated on the basis of CETS (shortest group = 44.0%, longest = 84.6%; P = 0.0033). In the multivariate logistic regression model, including gender, CETS, age, and family history of cancer, both gender and CETS were significantly associated with an incidence of activating EGFR mutations; the odds ratio for the EGFR mutations were 5.13 [95% confidence interval, CI = 1.47–18.0; P = 0.0105] for females and 1.02 (95% CI = 1.00–1.04; P = 0.0193) for each 1-year increment in CETS. Conclusions: Females and increased ETS exposure are closely associated with EGFR mutations in never-smokers with NSCLC. Clin Cancer Res; 17(1); 39–45. ©2010 AACR.