Tomoya Kawaguchi

Japanese-US Common-Arm Analysis of Paclitaxel Plus Carboplatin in Advanced Non–Small-Cell Lung Cancer: A Model for Assessing Population-Related Pharmacogenomics

PURPOSE To explore whether population-related pharmacogenomics contribute to differences in patient outcomes between clinical trials performed in Japan and the United States, given similar study designs, eligibility criteria, staging, and treatment regimens. METHODS We prospectively designed and conducted three phase III trials (Four-Arm Cooperative Study, LC00-03, and S0003) in advanced-stage, non-small-cell lung cancer, each with a common arm of paclitaxel plus carboplatin. Genomic DNA was collected from patients in LC00-03 and S0003 who received paclitaxel (225 mg/m(2)) and carboplatin (area under the concentration-time curve, 6). Genotypic variants of CYP3A4, CYP3A5, CYP2C8, NR1I2-206, ABCB1, ERCC1, and ERCC2 were analyzed by pyrosequencing or by PCR restriction fragment length polymorphism. Results were assessed by Cox model for survival and by logistic regression for response and toxicity. Results Clinical results were similar in the two Japanese trials, and were significantly different from the US trial, for survival, neutropenia, febrile neutropenia, and anemia. There was a significant difference between Japanese and US patients in genotypic distribution for CYP3A4*1B (P = .01), CYP3A5*3C (P = .03), ERCC1 118 (P < .0001), ERCC2 K751Q (P < .001), and CYP2C8 R139K (P = .01). Genotypic associations were observed between CYP3A4*1B for progression-free survival (hazard ratio [HR], 0.36; 95% CI, 0.14 to 0.94; P = .04) and ERCC2 K751Q for response (HR, 0.33; 95% CI, 0.13 to 0.83; P = .02). For grade 4 neutropenia, the HR for ABCB1 3425C-->T was 1.84 (95% CI, 0.77 to 4.48; P = .19). CONCLUSION Differences in allelic distribution for genes involved in paclitaxel disposition or DNA repair were observed between Japanese and US patients. In an exploratory analysis, genotype-related associations with patient outcomes were observed for CYP3A4*1B and ERCC2 K751Q. This common-arm approach facilitates the prospective study of population-related pharmacogenomics in which ethnic differences in antineoplastic drug disposition are anticipated.

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.

EGFR Mutation Status in Japanese Lung Cancer Patients: Genotyping Analysis Using LightCycler

Purpose: Recently, somatic mutations of the epidermal growth factor receptor (EGFR) gene were found in ∼25% of Japanese lung cancer patients. These EGFR mutations are reported to be correlated with clinical response to gefitinib therapy. However, DNA sequencing using the PCR methods described to date is time-consuming and requires significant quantities of DNA; thus, this existing approach is not suitable for a routine pretherapeutic screening program. Experimental Design: We have genotyped EGFR mutation status in Japanese lung cancer patients, including 102 surgically treated lung cancer cases from Nagoya City University Hospital and 16 gefitinib-treated lung cancer cases from Kinki-chuo Chest Medical Center. The presence or absence of three common EGFR mutations were analyzed by real-time quantitative PCR with mutation-specific sensor and anchor probes. Results: In exon 21, EGFR mutations (CTG → CGG; L858R) were found from 8 of 102 patients from Nagoya and 1 of 16 from Kinki. We also detected the deletion mutations in exon 19 from 7 of 102 patients from Nagoya (all were deletion type 1a) and 4 of 16 patients from Kinki (one was type 1a and three were type 1b). In exon 18, one example of G719S mutation was found from both Nagoya and Kinki. The L858R mutation was significantly correlated with gender (women versus men, P < 0.0001), Brinkman index (600 ≤ versus 600>, P = 0.001), pathologic subtypes (adenocarcinoma versus nonadenocarcinoma, P = 0.007), and differentiation status of the lung cancers (well versus moderately or poorly, P = 0.0439), whereas the deletion mutants were not. EGFR gene status, including the type of EGFR somatic mutation, was correlated with sensitivity to gefitinib therapy. For example, some of our gefitinib-responsive patients had L858R or deletion type 1a mutations. On the other hand, one of our gefitinib-resistant patients had a G719S mutation. Conclusions: Using the LightCycler PCR assay, the EGFR L858R mutation status might correlate with gender, pathologic subtypes, and gefitinib sensitivity of lung cancers. However, further genotyping studies are needed to confirm the mechanisms of EGFR mutations for the sensitivity or resistance of gefitinib therapy for the lung cancer.

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.

Increased serum levels of basic fibroblast growth factor in lung cancer patients: relevance to response of therapy and prognosis

Angiogenesis is controlled by inhibitors and angiogenic factors. Among these, basic fibroblast growth factor (bFGF) is closely involved in cancer proliferation and has been related to progression and prognosis of various cancers, including lung cancer. To evaluate the role of bFGF, we measured serum levels of bFGF from healthy controls (Ctrl) and 106 patients with lung cancer, including 31 adenocarcinomas (AD), 29 squamous cell carcinomas (SQ), and 46 small cell carcinomas (SCLC), by enzyme-linked immunosorbent assays. Moreover, we evaluated the relationship between serum levels of bFGF and clinical outcome. Serum levels of bFGF in AD, SQ, SCLC, and Ctrl were 7.6 (0.5-32.5) (median (range)), 7.4 (0.5-36.7), 7.1 (0.5-34.8) and 3.0 (1.5-6.0) pg/ml, respectively (P<0.05). Serum bFGF levels did not differ between clinical stages in non-small cell lung cancer (NSCLC; AD+SQ). In SCLC, we found a significant difference in serum levels of bFGF between chemotherapy (and/or radiotherapy) responders (complete response+partial response) and non-responders (no change+progressive disease) (9.2 (0.6-34.8), 4.4 (0.5-17.4) pg/ml, respectively (P=0.018)), whereas there was no difference in NSCLC. Moreover, serum bFGF levels in SCLC patients had significant impact in prognosis by uni and multivariate analysis (P=0.014, 0.018, respectively). We concluded that bFGF has an important role in the prognosis of patients with SCLC.

Phase II study of weekly irinotecan and carboplatin for refractory or relapsed small-cell lung cancer

We designed a phase II study of weekly irinotecan (CPT-11) and carboplatin for refractory or relapsed small cell lung cancer (SCLC) and assessed the response rate, survival, and toxicity. Twenty-nine patients with refractory or relapsed SCLC were entered onto the trial. The median time off chemotherapy was 3.5 months (range: 0.8-12.9). Patients were treated at 4-week intervals using CPT-11 (50 mg/m(2) intravenously on days 1, 8 and 15) plus carboplatin (AUC = 2 mg/ml min, intravenously on days 1, 8, 15). All patients were assessable for toxicity and survival; 28 patients were assessable for response. There were nine partial responses (PRs). Overall response rate was 31.0% (95% CI: 15.3-50.8%). The median time to progression was 3.5 months. Median survival time was 6.1 months. Major toxicity was myelosuppression. Grade 3 to 4 neutropenia and thrombocytopenia occurred in 52 and 21% of patients, respectively. Grade 3-4 diarrhea was observed in 7%. There was one treatment-related death due to febrile neutropenia and sepsis. This combination of CPT-11 and carboplatin seems to be active second-line regimen with acceptable toxicity against small cell lung cancer.

Mutant DNA in Plasma of Lung Cancer Patients: Potential for Monitoring Response to Therapy

Abstract: The hypothesis tested was that mutant tumor DNA shed into plasma would show predictive value for monitoring response to therapy in non‐small cell lung carcinoma patients. Pretreatment plasma specimens from 25 patients on a phase I trial were evaluated, 12 with paired posttreatment specimens, and 138 patients on the Southwest Oncology Group S0003 trial, 38 with paired posttreatment specimens, for the presence of K‐RAS mutations. Thirteen tumor specimens from the phase I trial patients and seven tumor specimens from S0003 patients were also available for comparative analysis of K‐RAS mutations in tumor tissue and plasma. All patients were treated similarly with paclitaxel, and carboplatin chemotherapy. DNA was extracted and mutational analyses performed using an RFLP‐PCR assay. K‐RAS mutations were found in plasma DNA in 5/25 of the phase I patients (20%). Median survival was 10 months in all patients, 11.4 months in the wild‐type K‐RAS group, and 3.3 months in the mutant K‐RAS group (P= 0.056). Point mutations in plasma DNA were identical to mutations found in the tumors, confirming the tumor as the source. In two patients with K‐RAS mutations pretreatment, posttreatment plasmas were evaluated: a patient with clinical progressive disease retained the mutant DNA, while in a patient with a complete response (CR), the K‐RAS mutation was no longer detectable. In an ongoing analysis of S0003 patients, to date, K‐RAS mutations have been found in the plasma of 14 patients (10.1%). In 42 matched pre‐ and posttreatment specimens from both phase I and S0003 trials, four patients had K‐RAS mutations pretreatment that were not detectable posttreatment. Of these, two had a clinical CR or partial response, and the other two had stable disease. It was concluded that detection of tumor DNA in plasma is feasible using molecular techniques and that this approach shows promise for monitoring patient response to therapy.

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.