Assessment of exposure risk of irinotecan and its active metabolite, SN-38, through perspiration during chemotherapy.

BACKGROUND: Irinotecan (CPT-11) is the key drug used in chemotherapy for many malignant tumors. CPT-11 has cholinergic activity and induces perspiration during intravenous administration. In this study, concentrations of CPT-11 and its active metabolite, SN-38, released during perspiration were measured and risk of exposure of these drugs was assessed. METHOD: Beads of sweat were collected using a dropper from four patients undergoing a chemotherapy regimen involving intravenous administration of CPT-11. The concentrations of CPT-11 and SN-38 in sweat were measured using liquid chromatography tandem mass spectrometry. RESULT: Chemotherapy regimens were capecitabine and irinotecan plus bevacizumab (n = 1), CPT-11 monotherapy (n = 1), and oxaliplatin-irinotecan-leucovorin-5-fluorouracil (n = 2). Uridine diphosphate-glucuronosyltransferase 1A1 phenotypes were *6 homo-type (n = 1), *6 hetero-type (n = 1), and wild type (n = 2). CPT-11 dose was 292.3 ± 75.5 mg/body weight (mean ± standard deviation). CPT-11 was detected in sweat secreted by all the four patients, and its mean (±standard deviation) concentration was 252.6 (±111.9) ng/ml. SN-38 was detected in only one of the patients who received oxaliplatin-irinotecan-leucovorin-5-fluorouracil treatment and who had the wild-type uridine diphosphate-glucuronosyltransferase 1A1 phenotype at a concentration of 74.37 ng/ml. CONCLUSION: CPT-11 and SN-38 are detected in sweat released during intravenous CPT-11 administration. Beads of sweat or linen clothes that absorb the sweat might be the source of CPT-11 and SN-38 exposure.

Does afatinib plus bevacizumab combination therapy induce positive conversion of T790M in previously-negative patients?

Third-generation epidermal growth factor receptor (EGFR)-tyrosine kinase inhibitors (TKIs) are markedly effective for T790M-positive patients. To confer their clinical benefit to more patients, a novel therapy to induce positive conversion in T790M-negative patients may be possible. We retrospectively reviewed medical records of patients who had received rebiopsy after completion of ABC-study: a prospective phase II study of Afatinib plus Bevacizumab Combination (ABC)-therapy after acquired resistance to EGFR-TKI. Between October 2014 and September 2016, 32 eligible patients were enrolled in ABC-study at our institutes. Eighteen patients were T790M-negative and 14 were T790M-positive before ABC-therapy. Rebiopsy was performed on 13 T790M-negative and 5 T790M-positive patients after progression of ABC-therapy. In 8 (62%) of 13 T790M-negative patients, T790M status changed from negative to positive after ABC-therapy. Seven of these 8 patients underwent osimertinib therapy. The response rate and median time to treatment failure were 86% and 12.2 months, respectively. There were no adverse events ≥grade 3, nor any treatment-related deaths. On the other hand, T790M remained positive after ABC-therapy in all 5 previous T790M-positive patients. ABC-therapy could induce positive conversion of T790M even in previously-negative patients. We hypothesize that ABC-therapy could provoke "clonal selection", which purifies T790M-positive cancer cells in heterogeneous tumors. Further studies are warranted to confirm this phenomena.

Afatinib plus bevacizumab combination after acquired resistance to EGFR tyrosine kinase inhibitors in EGFR-mutant non-small cell lung cancer: Multicenter, single-arm, phase 2 trial (ABC Study).

BACKGROUND: Preclinical studies suggested that the addition of bevacizumab could overcome acquired resistance (AR) to epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs). The aim of this study was to evaluate the clinical efficacy and safety of a combination of afatinib and bevacizumab after AR. METHODS: Patients with EGFR-mutant non-small cell lung cancer after AR were enrolled during any line of therapy. Afatinib was prescribed at 30 mg, and 15 mg/kg bevacizumab was administered every 3 weeks until progression. RESULTS: Between October 2014 and May 2017, 32 eligible patients were evaluated. The mutation subtypes were Del-19 (20 [63%]), L858R (11 [34%]), and L861Q (1 [3%]). T790M was detected in 14 patients (44%). The median number of prior regimens was 4 (range, 1-10). Six patients obtained a partial response, and 23 had stable disease; this resulted in an objective response rate (ORR) of 18.8% (95% confidence interval [CI], 7.2%-36.4%) and a disease control rate of 90.7% (95% CI, 75.0%-98.0%). The median progression-free survival (PFS) was 6.3 months (95% CI, 3.9-8.7 months). The ORRs and median PFS times of T790M+ and T790M- patients were 14.3% and 22.2%, respectively, and 6.3 and 7.1 months, respectively; those of Del-19 and L858R patients were 20.0% and 11.1%, respectively, and 6.3 and 5.1 months, respectively. Grade 3 or higher adverse events (incidence ≥ 10%) included paronychia (25%), hypertension (41%), and proteinuria (19%). There were no treatment-related deaths, interstitial lung disease, or bevacizumab-associated severe bleeding. CONCLUSIONS: Afatinib plus bevacizumab demonstrated clinical efficacy and safety after AR to EGFR TKIs and could be a therapeutic salvage option for T790M- populations.

An LC-MS/MS Method for Absolute Quantification of Nivolumab in Human Plasma: Application to Clinical Therapeutic Drug Monitoring.

BACKGROUND: Nivolumab is a fully humanized IgG4 monoclonal antibody that targets the programmed death-1 (PD-1) receptor, disrupting PD-1-mediated signaling and restoring antitumor immunity. The objective of this study was to develop a nivolumab quantification method using liquid chromatography-tandem mass spectrometry (LC-MS/MS) and to evaluate its application in clinical therapeutic drug monitoring. METHODS: Nivolumab was purified from human plasma using rProtein A resin and then digested with trypsin. The ASGITFSNSGMHWVR peptide (multiple reaction monitoring transition: m/z 550.6→661.4) was detected as a surrogate peptide of nivolumab by triple quadrupole mass spectrometry. Plasma samples (126) were collected from 14 patients with non-small cell lung cancer who were undergoing clinical dosing regimen with nivolumab. The pharmacokinetic data were analyzed using Phoenix NLME software (Version 7.0, Certara, St. Louis, MO) based on a previously reported population pharmacokinetics (PPK) model of nivolumab. RESULTS: Nivolumab was selectively detected in human plasma and the linear range was 5-200 mcg/mL (R = 0.99). The accuracy and intraday and interday imprecision were within ±15% of the quality control values of 5 (lower limit of quantification), 10 (low), 80 (medium), and 160 (high) mcg/mL. The nivolumab concentrations measured using LC-MS/MS were consistent with those of previously reported PPK models, and the pharmacokinetic parameters could be adequately predicted from a single trough concentration using a Bayesian approach. CONCLUSIONS: An absolute quantification method for nivolumab using LC-MS/MS was successfully developed and validated. Combined with PPK analysis, this method should be useful for the therapeutic drug monitoring of nivolumab in clinical practice.

Docetaxel plus ramucirumab with primary prophylactic pegylated-granulocyte-colony stimulating factor for pretreated non-small cell lung cancer.

PURPOSE: The aim of our study was to evaluate the efficacy and safety of docetaxel plus ramucirumab with primary prophylactic pegylated (PEG)-granulocyte-colony stimulating factor (G-CSF) for pretreated non-small cell lung cancer (NSCLC). RESULTS: Sixty-one pretreated NSCLC patients underwent docetaxel plus ramucirumab. Primary prophylactic PEG-G-CSF was performed in 52 (85%) patients (prophylactic group). No febrile neutropenia (FN) (0%) was confirmed in 52 prophylactic group patients, whereas FN was observed in 3 (33%) of 9 non-prophylactic group patients. Among prophylactic group, median lines of prior therapy was 2 (range, 1-9). Median cycles of docetaxel plus ramucirumab was 3 (range, 1-25) (9 and 3 cases moved to ramucirumab and docetaxel monotherapies, respectively). Response rate and disease control rate were 30.8% and 73.1%, respectively. Median progression-free survival was 4.5 (95% confidence interval [CI], 3.0-6.6) months. Median overall survival was 11.4 (95% CI, 8.0-13.9) months. Six (11.5%) patients had grade 3/4 neutropenia. Observed grade 3 (incidence ≥10%) adverse event (AE) was oral mucositis (13.5%). There were no grade 4/5 non-hematological AEs. CONCLUSIONS: Our study demonstrated the efficacy and safety of docetaxel plus ramucirumab with PEG-G-CSF in clinical practice. Primary prophylactic PEG-G-CSF could markedly reduce incidence of FN. METHODS: We retrospectively reviewed medical records of pretreated NSCLC cases who had received docetaxel plus ramucirumab in our departments.

Sleeve lobectomy for lung adenocarcinoma treated with neoadjuvant afatinib.

Afatinib, the second-generation epidermal growth factor receptor tyrosine kinase inhibitor (EGFR-TKI), has been postulated to be associated with improved inhibition of EGFR-dependent tumor growth compared with first-generation EGFR-TKIs for advanced non-small cell lung cancer (NSCLC). We present a case of lung adenocarcinoma (cT3N0M0) treated with neoadjuvant afatinib and sleeve lobectomy. Because of the location of the tumor, reduced FEV1 value, and the presence of EGFR mutation, the patient was planned to be prescribed afatinib (30 mg daily) for 3 weeks as neoadjuvant therapy and underwent sleeve lobectomy to avoid pneumonectomy as much as possible. Although the patient presented with grade 3 diarrhea and dose reduction of afatinib to 20 mg daily was needed, several image findings showed a partial response of the tumor on Day 20. Oral administration of afatinib was discontinued on Day 22. A right upper sleeve lobectomy combined with partial resection of lower lobe was performed after oral administration of afatinib on Day 24. The patient's postoperative course was uneventful and she has been free of recurrence for 26 months. This strategy could reduce the risk of pneumonectomy with acceptable side effects. The treatment, clinical course and pathological findings of the patient are discussed.

Development and validation of a method for gefitinib quantification in dried blood spots using liquid chromatography-tandem mass spectrometry: Application to finger-prick clinical blood samples of patients with non-small cell lung cancer.

A liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was developed and validated for the quantification of gefitinib in dried blood spots (DBSs). Gefitinib was extracted with methanol from DBS of 3 mm in diameter and detected using a triple quadrupole mass spectrometer. The method was validated by evaluating its precision, accuracy, selectivity, carryover, matrix effect, recovery, and stability. For clinical validation, paired finger-prick DBS and plasma concentrations were compared for 10 patients with non-small cell lung cancer (NSCLC) taking gefitinib. The calibration linear range was 37.5-2400 ng/mL (coefficient of determination [R2] = 0.99), encompassing the therapeutic concentrations of gefitinib. The accuracy and precision were within 15% of the quality control (QC) concentrations of 80, 200, and 2000 ng/mL. The lower limit of quantification was determined to be 40 ng/mL. Gefitinib was stable in DBSs for up to 5 months at room temperature and -20 °C, and at 40 °C for 24 h. A good correlation was observed between the gefitinib levels measured by the DBS method and plasma concentrations (R2 = 0.99). This method provides a simple, fast, and accurate approach to the quantitative analysis of gefitinib in finger-prick DBSs. The method would be useful for minimally invasive evaluation of the clinical gefitinib blood concentration.

Atezolizumab in Japanese Patients With Previously Treated Advanced Non-Small-Cell Lung Cancer: A Subgroup Analysis of the Phase 3 OAK Study.

INTRODUCTION: Atezolizumab, an anti-programmed death-ligand 1 (PD-L1) agent, is effective and well tolerated in patients with pretreated advanced non-small-cell lung cancer (NSCLC). We assessed its efficacy and safety in Japanese patients through subgroup analyses of the phase 3 OAK study (NCT02008227). PATIENTS AND METHODS: Key eligibility criteria of this randomized, controlled, open-label, international study include locally advanced/metastatic NSCLC, ≥ 1 prior platinum-based chemotherapy, age ≥ 18 years, measurable disease (Response Evaluation Criteria in Solid Tumors v1.1), and Eastern Cooperative Oncology Group performance status 0 or 1. Atezolizumab 1200 mg or docetaxel 75 mg/m2 was provided intravenously every 3 weeks. Co-primary end points were overall survival (OS) in the intention-to-treat (ITT) population and those with ≥ 1% PD-L1 expression on tumor cells (TC) or tumor-infiltrating immune cells (IC; TC1/2/3 or IC1/2/3). RESULTS: Sixty-four ITT patients were Japanese; 19 had TC1/2/3 or IC1/2/3 status. In Japanese ITT patients, median OS in the atezolizumab arm (n = 36) was longer than the docetaxel arm (n = 28; 21.3 months [95% confidence interval (CI), 11.0-not estimable (NE)] versus 17.0 months [95% CI, 12.5-NE], respectively; hazard ratio 0.80 [95% CI, 0.41-1.57]). In the TC1/2/3 or IC1/2/3 population, median OS was 21.3 months (95% CI, 15.0-NE) and NE in the atezolizumab (n = 11) and docetaxel (n = 8) groups, respectively (hazard ratio, 0.81 [95% CI, 0.22-3.05]). Atezolizumab was generally well tolerated, with no treatment-related deaths. CONCLUSION: Atezolizumab was effective and well tolerated in pretreated Japanese patients with NSCLC. Results are consistent with the primary analysis of OAK.

Validation of the digital PCR system in tyrosine kinase inhibitor-resistant EGFR mutant non-small-cell lung cancer.

The aim of this study was to compare the accuracy of the QuantStudio 3D Digital polymerase chain reaction (dPCR) system and a PCR-based next generation sequencing (NGS) system for detecting a secondary mutation in the epidermal growth factor receptor (EGFR) gene T790M in non-small cell lung cancer (NSCLC) patients previously diagnosed with EGFR-activating mutations. Twenty-five patients with NSCLC previously treated with EGFR-TKIs were examined. The patients were treated daily with either erlotinib or gefitinib. New biopsies, followed by DNA sequencing on an Ion Torrent systems using the Ion Torrent AmpliSeq Cancer Hotspot Panel and dPCR were performed. A comparison of NGS, sensitive PCR, and dPCR revealed that the sensitivities of NGS and dPCR were similar in this study. As well, T790M was detected in as low as about 5% of mutant allelic frequencies, which represented 5% of the total reads on site mapped reads in NGS and greater than 5% of the dPCR reads, which represented mutant and wild type copies. The strategy in which NGS sequencing is followed by revealed acquired mutation with dPCR may be a reasonable one. We demonstrated the utility of combining NGS and dPCR as a tool for monitoring T790M. NGS and dPCR with formalin-fixed paraffin-embedded (FFPE) specimens might become a standard genomic test for exploring acquired resistance to targeted molecular medicines.

Standard-dose osimertinib for refractory leptomeningeal metastases in T790M-positive EGFR-mutant non-small cell lung cancer.

BACKGROUND: Osimertinib demonstrated promising efficacy for refractory leptomeningeal metastases (LM) in preclinical data and a clinical study at 160 mg, but there is limited data for the standard 80 mg dose. METHODS: T790M-positive patients with suspected LM after classical epidermal growth factor receptor-tyrosine kinase inhibitor (EGFR-TKI) failure were enroled. RESULTS: We investigated 13 patients (5 definitive and 8 possible LM cases). In two of the five definitive cases with T790M in and outside the central nervous system (CNS), osimertinib was effective for both lesions, with cerebrospinal fluid (CSF) clearance of cancer cells and sensitive/T790M mutations. In three definitive cases with extra-CNS T790M without CSF T790M, cancer cells and sensitive mutations in the CSF persisted after osimertinib initiation. The median progression-free survival of all 13 patients was 7.2 months. Osimertinib was generally well-tolerated despite poor performance status, but interstitial lung disease (grade 2) was confirmed in one patient. Based on 25 samples from 13 patients, the osimertinib CSF penetration rate was 2.5±0.3%. CONCLUSIONS: Osimertinib 80 mg is a useful therapeutic option for refractory LM after classical EGFR-TKI failure. It appears more effective in CSF T790M-positive cases.

Programmed death-ligand 1 expression and T790M status in EGFR-mutant non-small cell lung cancer.

BACKGROUND: Differential biology and prognosis between T790M+ and T790M- populations imply immunological differences also. METHODS: We retrospectively analyzed programmed death-ligand 1 (PD-L1) expression and T790M status in rebiopsied samples of epidermal growth factor receptor (EGFR)-mutant non-small cell lung cancer (NSCLC). PD-L1 immunohistochemistry was performed using the SP142 antibody for tumour cell (TC) and tumour-infiltrating immune cell (IC) and the 28-8 antibody for TC. PD-L1+ was defined as TC or IC ≥1%. RESULTS: We investigated 67 available rebiopsied histologic samples in 47 patients. Using the SP142, prevalence of PD-L1 any+, moderate+, and strong+ in T790M+ vs. T790M- samples were 31% vs. 61%, 8% vs. 15%, and 0% vs. 2%, respectively, representing PD-L1+ prevalence of T790M+ samples was significantly lower than that of T790M- (p=0.0149). Prevalence of any TC+/IC+ in T790M+ vs. T790M- samples were TC: 31% vs. 51% (p=0.0997) and IC: 8% vs. 27% (p=0.0536), respectively. Using the 28-8, median percentage of PD-L1+ in T790M+ samples was 1.9 (range, 0-27.2), whereas T790M- was 4.1 (range, 0-89.8) (p=0.0801). Prevalence of PD-L1+ ≥1%, ≥5%, and ≥10% in T790M+ vs. T790M- samples were 77% vs. 83% (p=0.5476), 31% vs. 49% (p=0.1419), and 12% vs. 27% (p=0.1213), respectively. In 9 of 11 patients receiving multiple rebiopsies, T790M and/or PD-L1 expression revealed temporal dynamism. Survival curves according to PD-L1 expression/T790M status suggested better prognosis in PD-L1-/T790M+ population. CONCLUSIONS: T790M+ status was correlated to lower PD-L1 expression. PD-L1 expression might have a prognostic value and interaction with T790M mutation in EGFR-mutant NSCLC.

Single nucleotide variant sequencing errors in whole exome sequencing using the Ion Proton System.

Errors in sequencing are a major obstacle in the interpretation of next-generation sequencing (NGS) results. In the present study, sequencing errors identified from analysis of single nucleotide variants (SNVs) identified during exome sequencing of human germline DNA were studied using the Thermo Fisher Ion Proton System. Two consanguineous cases were selected for sequencing using the AmpliSeq Exome capture kit, and SNVs found in both cases were validated using Sanger sequencing. A total of 98 SNVs detected by NGS were randomly selected for further analysis. Nine of the analyzed SNVs were shown to be false positives when confirmed by Sanger sequencing. All but one SNV were considered to be homopolymer regions, mainly through the insertion or deletion of nucleotides. The remaining error was considered to be related to the primer. The present results revealed that the majority of the SNV sequencing errors originated from homopolymer insertion/deletion errors, which are commonly observed when using the Ion Torrent system.

PD-L1 Expression in Patients with Non-small Cell Lung Cancer.

AIM: The aim of this study was to evaluate whether irradiation induces the expression of tumor programed cell death ligand 1 (PD-L1) in patients with non-small cell lung cancer (NSCLC). PATIENTS AND METHODS: Seventeen patients with NSCLC who received chemoradiotherapy and underwent tumor resection and six patients whose pre-treatment biopsy specimens were available, were analyzed by immunohistochemistry for PD-L1 expression between September 2011 and June 2016 at the Institute of Biomedical Research and Innovation Hospital. RESULTS: Among six patients for which pre-irradiation biopsy samples were available, the H-score for PD-L1 was reduced after irradiation following staining with two different antibody clones (SP28-8 and SP142). A PD-L1 H-score >5 with SP28-8 antibody (hazard ratio=6.46; 95% confidence interval=1.209-34.53; p=0.029) was a significant negative factor for duration of progression-free survival after curative operation or chemoradiation. CONCLUSION: We showed that tumor PD-L1 expression decreased in patients with NSCLC who received chemoradiotherapy and radiation resistance might be due to pre-treatment PD-L1 expression.

Rebiopsy of Histological Samples in Pretreated Non-small Cell Lung Cancer: Comparison Among Rebiopsy Procedures.

AIM: The aim of the present study was to compare successful rate, failure reasons, and complications among procedures of histological rebiopsy. PATIENTS AND METHODS: We retrospectively reviewed medical records of histologically rebiopsied cases with non-small cell lung cancer. RESULTS: One hundred and eleven histological rebiopsies were performed in: 86 (77%) lung; 11 (10%) lymph node; 5 (5%) pleura; 4 (4%) liver; 2 (2%) muscle; 2 (2%) adrenal gland; and 1 (1%) rib. Successful rate by computed tomography-guided biopsy (CTGB), transbronchial biopsy (TBB), and ultrasound-guided biopsy were 86% (48/56), 90% (28/31), and 100% (24/24), respectively. Reasons for rebiopsy failure by CTGB were no/insufficient malignant cells (n=5) and pneumothorax (n=3), and those by TBB were no/insufficient malignant cells (n=2) and bleeding (n=1). Severe complications (≥grade 3): one grade 3 pneumothorax and one grade 4 air embolization were observed in two (2%, 2/111) cases receiving CTGB. CONCLUSION: Rebiopsy of histological samples can be highly successful and feasible by optimal procedural selection.

Programmed death-ligand 1 expression according to epidermal growth factor receptor mutation status in pretreated non-small cell lung cancer.

BACKGROUND: Current clinical trials have suggested poorer efficacies of anti-programmed death-1 (PD-1)/PD-ligand 1 (PD-L1) immunotherapies for non-small cell lung cancer (NSCLC) harboring epidermal growth factor receptor (EGFR) mutations, implying lower PD-L1 expression in EGFR-mutant NSCLC than in EGFR-wild type. METHODS: We retrospectively analyzed correlation between PD-L1 expression and EGFR status in clinical samples of pretreated NSCLC. PD-L1 immunohistochemistry was performed using the 28-8 anti-PD-L1 antibody for tumor cell membrane staining. H-score was adopted to evaluate both percentage and intensity. We investigated H-scores ≥1, ≥5, and ≥10 as PD-L1+ cut-offs. H-score ≥10 was defined as strong PD-L1+. RESULTS: We investigated 96 available histologic samples in 77 pretreated patients with NSCLC. Median H-score in EGFR-mutant samples (n=65) was 3 (range, 0-150), whereas EGFR-wild-type (n=31) was 8 (range, 0-134) (p=0.0075). Using H-scores ≥1, ≥5, and ≥10 cut-offs, incidence of PD-L1+ in EGFR-mutant vs. EGFR-wild-type samples were: 85% (55/65) vs. 94% (29/31) (p=0.2159); 42% (27/65) vs. 74% (23/31) (p=0.0027); and 22% (14/65) vs. 48% (15/31) (p=0.0074), respectively. Patient-oriented (n=77) univariate analysis for strong PD-L1+ found age of sample (p=0.0226) and EGFR mutation status (p=0.0490) as significant factors. Multivariate analysis identified EGFR mutation status as the only significant factor (p=0.0121, odds ratio 2.99) for strong PD-L1+. H-scores of PD-L1 expression varied in all 11 cases receiving multiple rebiopsies, and categories of positivity migrated in 10 (91%) of 11 patients. CONCLUSIONS: PD-L1 expression was significantly lower in EGFR-mutant NSCLC samples than in EGFR wild-type samples. Its expression could be dynamic and affected by age of sample.

Randomized Phase III Study Comparing Gefitinib With Erlotinib in Patients With Previously Treated Advanced Lung Adenocarcinoma: WJOG 5108L.

PURPOSE: The epidermal growth factor receptor (EGFR) tyrosine kinase has been an important target for non-small-cell lung cancer. Several EGFR tyrosine kinase inhibitors (TKIs) are currently approved, and both gefitinib and erlotinib are the most well-known first-generation EGFR-TKIs. This randomized phase III study was conducted to investigate the difference between these two EGFR-TKIs. PATIENTS AND METHODS: Previously treated patients with lung adenocarcinoma were randomly assigned to receive gefitinib or erlotinib. This study aimed to investigate the noninferiority of gefitinib compared with erlotinib. The primary end point was progression-free survival (PFS). RESULTS: Five hundred sixty-one patients were randomly assigned, including 401 patients (71.7%) with EGFR mutation. All baseline factors (except performance status) were balanced between the arms. Median PFS and overall survival times for gefitinib and erlotinib were 6.5 and 7.5 months (hazard ratio [HR], 1.125; 95% CI, 0.940 to 1.347; P = .257) and 22.8 and 24.5 months (HR, 1.038; 95% CI, 0.833 to 1.294; P = .768), respectively. The response rates for gefitinib and erlotinib were 45.9% and 44.1%, respectively. Median PFS times in EGFR mutation-positive patients receiving gefitinib versus erlotinib were 8.3 and 10.0 months, respectively (HR, 1.093; 95% CI, 0.879 to 1.358; P = .424). The primary grade 3 or 4 toxicities were rash (2.2% for gefitinib v 18.1% for erlotinib) and alanine aminotransferase (ALT)/aspartate aminotransferase (AST) elevation (6.1%/13.0% for gefitinib v 2.2%/3.3% for erlotinib). CONCLUSION: The study did not demonstrate noninferiority of gefitinib compared with erlotinib in terms of PFS in patients with lung adenocarcinoma according to the predefined criteria.

Next-generation sequencing of tyrosine kinase inhibitor-resistant non-small-cell lung cancers in patients harboring epidermal growth factor-activating mutations.

BACKGROUND: The aim of this study was to detect the epidermal growth factor receptor (EGFR)-activating mutations and other oncogene alterations in patients with non-small-cell lung cancers (NSCLC) who experienced a treatment failure in response to EGFR-tyrosine kinase inhibitors (TKIs) with a next generation sequencer. METHODS: Fifteen patients with advanced NSCLC previously treated with EGFR-TKIs were examined between August 2005 and October 2014. For each case, new biopsies were performed, followed by DNA sequencing on an Ion Torrent Personal Genome Machine (PGM) system using the Ion AmpliSeq Cancer Hotspot Panel version 2. RESULTS: All 15 patients were diagnosed with NSCLC harboring EGFR-activating mutations (seven cases of exon 19 deletion, seven cases of L858R in exon 21, and one case of L861Q in exon 21). Of the 15 cases, acquired T790M resistance mutations were detected in 9 (60.0%) patients. In addition, other mutations were identified outside of EGFR, including 13 cases (86.7%) exhibiting TP53 P72R mutations, 5 cases (33.3%) of KDR Q472H, and 2 cases (13.3%) of KIT M541L. CONCLUSIONS: Here, we showed that next-generation sequencing (NGS) is able to detect EGFR T790M mutations in cases not readily diagnosed by other conventional methods. Significant differences in the degree of EGFR T790M and other EGFR-activating mutations may be indicative of the heterogeneity of disease phenotype evident within these patients. The co-existence of known oncogenic mutations within each of these patients may play a role in acquired EGFR-TKIs resistance, suggesting the need for alternative treatment strategies, with PCR-based NGS playing an important role in disease diagnosis.

EGFR-TKI rechallenge with bevacizumab in EGFR-mutant non-small cell lung cancer.

BACKGROUND: Efficacies of epidermal growth factor receptor (EGFR)-tyrosine kinase inhibitor (TKI) rechallenge have been demonstrated in EGFR-mutant non-small cell lung cancer (NSCLC). However, their efficacies were only moderate. Some preclinical studies suggested synergistic effects of bevacizumab to EGFR-TKI in TKI-resistant models. METHODS: We retrospectively evaluated clinical efficacy and safety of EGFR-TKI rechallenge with bevacizumab. Rebiopsy was performed on all studied cases to examine T790M-resistant mutation status. RESULTS: Between January 2010 and June 2014, a total of 24 EGFR-mutant NSCLC patients who had been previously treated with EGFR-TKIs (gefitinib, erlotinib, and/or afatinib) received EGFR-TKI rechallenge with bevacizumab. Twenty-two (92 %) patients underwent erlotinib and two (8 %) gefitinib as rechallenge EGFR-TKIs in combination with bevacizumab. Three patients achieved partial response, and 18 had stable disease, resulting in the response rate (RR) of 13 % and disease control rate (DCR) of 88 %, respectively. The median progression-free survival (PFS) was 4.1 [95 % confidence interval (CI) 2.3-4.9] months, and the median overall survival (OS) was 13.5 (95 % CI 9.7-27.4) months. The RR, DCR, median PFS, and median OS for T790M-positive versus T790M-negative were 0 versus 18 % (p = 0.530), 86 versus 88 % (p = 1.00), 3.3 versus 4.1 months (p = 0.048), and 15.1 versus 13.5 months (p = 0.996), respectively. Severe adverse events (≥grade 3): grade 3 of 1 (4 %) rash; grade 3 of 1 (4 %) paronychia; grade 3 of 1 (4 %) hypertension; and grade 3 of 1 (4 %) anemia, were observed. CONCLUSIONS: EGFR-TKI rechallenge with bevacizumab demonstrated higher DCR and modestly longer PFS than historical data on EGFR-TKI rechallenge alone. Its activity was notably higher in T790M-negative population.

Spatiotemporal T790M Heterogeneity in Individual Patients with EGFR-Mutant Non-Small-Cell Lung Cancer after Acquired Resistance to EGFR-TKI.

INTRODUCTION: Epidermal growth factor receptor (EGFR) mutation T790M accounts for approximately half of acquired resistances to EGFR-tyrosine kinase inhibitor (TKI). Because T790M is mediated by TKI exposure, its penetration and "on-off" may affect T790M status. METHODS: We retrospectively reviewed T790M status and clinical course of patients who had undergone multiple rebiopsies after acquired resistance to EGFR-TKI. RESULTS: Of 145 patients with EGFR-mutant NSCLC receiving rebiopsy after acquired resistance, 30 underwent multiple site rebiopsies, and 24 received repeated rebiopsies at the same lesion. In 22 patients who underwent rebiopsies from both central nervous system (CNS; 20 cerebrospinal fluids [CSF] and 2 brain tumoral tissues) and thoracic lesions (7 lung tissues, 14 pleural effusions, and 1 lymph node), 12 were thoracic-T790M-positive. Of these 12 patients, 10 were CNS-T790M-negative, despite exhibiting thoracic-T790M-positive. All 10 thoracic-T790M-negatives were CNS-T790M-negative. Three patients revealed a spatial heterogeneous T790M status among their thoracic lesions. In 24 patients receiving repeated rebiopsies at the same lesion (12 lung tissues, 6 CSFs, and 6 pleural effusions), T790M status of lung lesions varied in five patients after TKI-free interval. In all five patients whose T790M status changed from positive to negative, EGFR-TKI rechallenge was effective. In three of these five patients, after further TKI exposure, T790M status changed from negative to positive again. There was also a patient whose CSF T790M status changed from negative to positive after high-dose erlotinib therapy. CONCLUSIONS: T790M status in an individual patient can be spatiotemporally heterogeneous because of selective pressure from EGFR-TKI.

Effectiveness of Tyrosine Kinase Inhibitors in Japanese Patients with Non-small Cell Lung Cancer Harboring Minor Epidermal Growth Factor Receptor Mutations: Results from a Multicenter Retrospective Study (HANSHIN Oncology Group 0212).

AIM: Non-small cell lung cancer (NSCLC) with minor mutations in the epidermal growth factor receptor (EGFR) gene, except for the common 15 base-pair deletions in exon 19 and the L858R mutation in exon 21, is rare, and only few data exist on this patient population. The aim of the present study was to describe the clinical characteristics and to clarify the efficacy of EGFR-tyrosine kinase inhibitors (TKIs) in patients with NSCLC harboring minor mutations of the EGFR gene. PATIENTS AND METHODS: This was a multicenter, retrospective study that analyzed specimens from patients with NSCLC who had minor EGFR gene mutations and were treated with EGFR-TKIs between June 2002 and March 2012. RESULTS: Out of 56 patients with minor mutations of the EGFR gene, 44 were treated with either gefitinib or erlotinib. Mutation sites were G719X in exon 18 (n=35), L861Q in exon 21 (n=11), and G874S in exon 21 (n=1). Three patients had both the G719S and the L861Q mutation. The response rate to TKI treatment was 29.5%, and the disease control rate was 63.6%. The median progression-free survival (PFS) was 6.7 months [95% confidence interval (CI)=2.06-8.66 months]. The median PFS was 7.2 months (95% CI=4.23-12.3 months) in 32 patients who received first- or second-line treatment with EGFR-TKIs, whereas the median PFS was 1.57 months (95% CI=0.73-3.8 months) in 12 patients treated with EGFR-TKIs as a third-line or later treatment. In multivariate Cox analysis, erlotinib therapy was associated with a longer PFS than gefitinib (p=0.025). CONCLUSION: Patients with NSCLC harboring minor mutations of the EGFR gene exhibited a modest response to EGFR-TKI treatment. Treatment with first-generation EGFR-TKIs, in particular erlotinib, may be considered a first- or second-line option for patients with NSCLC with minor EGFR mutations.