Hidenobu Ishii

Predictive relevance of PD-L1 expression combined with CD8+ TIL density in stage III non-small cell lung cancer patients receiving concurrent chemoradiotherapy.

BACKGROUND Expression of programmed cell death-ligand 1 (PD-L1) is known to be a mechanism whereby cancer can escape immune surveillance, but little is known about factors predictive of efficacy in patients with locally advanced non-small cell lung cancer (NSCLC). We investigated the predictive relevance of PD-L1 expression and CD8+ tumour-infiltrating lymphocytes (TILs) density in patients with locally advanced NSCLC receiving concurrent chemoradiotherapy (CCRT). METHODS We retrospectively reviewed 74 consecutive patients with stage III NSCLC who had received CCRT. PD-L1 expression and CD8+ TIL density were evaluated by immunohistochemical analysis. RESULTS Univariate and multivariate analyses demonstrated that CD8+ TIL density was an independent and significant predictive factor for progression-free survival (PFS) and OS, whereas PD-L1 expression was not correlated with PFS and OS. Sub-analysis revealed that the PD-L1+/CD8 low group had the shortest PFS (8.6 months, p = 0.02) and OS (13.9 months, p = 0.11), and that the PD-L1-/CD8 high group had the longest prognosis (median PFS and OS were not reached) by Kaplan-Meier curves of the four sub-groups. CONCLUSIONS Among stage III NSCLC patients who received CCRT, there was a trend for poor survival in those who expressed PD-L1. Our analysis indicated that a combination of lack of PD-L1 expression and CD8+ TIL density was significantly associated with favourable survival in these patients. It is proposed that PD-L1 expression in combination with CD8+ TIL density could be a useful predictive biomarker in patients with stage III NSCLC.

Significance of Programmed Cell Death-Ligand 1 Expression and its Association with Survival in Patients with Small Cell Lung Cancer

Background: Programmed cell death 1 receptor–ligand interaction is a major pathway often hijacked by tumors to suppress immune control. The aim of this retrospective study was to investigate the prevalence and prognostic roles of programmed cell death -ligand 1 (PD-L1) expression in small cell lung cancer (SCLC). Methods: The expression of PD-L1 was evaluated by immunohistochemical analysis in 102 specimens of SCLC. Tumors with staining in over 5% of tumor cells were scored as positive for PD-L1 expression. Survival analysis was performed using the Kaplan–Meier method. Results: Expression of PD-L1 in tumor cells was observed in 71.6% (73 of 102) of SCLCs, and was significantly correlated with a limited disease (LD) stage. SCLC patients with PD-L1-positive tumors showed significantly longer overall survival (OS) than those with PD-L1-negative (median OS, 16.3 versus 7.3 months; p < 0.001, respectively). Multivariate analyses demonstrated that a good performance status, LD stage, and expression of PD-L1 were significantly predictive of better OS, independently of other factors. We found no relevance between PD-L1 expression and progression-free survival for first-line treatment in LD- and extensive disease-SCLC patients. Conclusions: In patients with SCLC, expression of PD-L1 is positively correlated with a LD stage, and is independently predictive of a favorable outcome.

Digital PCR analysis of plasma cell-free DNA for non-invasive detection of drug resistance mechanisms in EGFR mutant NSCLC: Correlation with paired tumor samples

As the development of resistance to epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs) has become an issue of concern, identification of the mechanisms responsible has become an urgent priority. However, for research purposes, it is not easy to obtain tumor samples from patients with EGFR mutation-positive non-small-cell lung cancer (NSCLC) that has relapsed after treatment with EGFR-TKIs. Here, using digital PCR assay as an alternative and noninvasive method, we examined plasma and tumor samples from patients with relapsed NSCLC to establish the inter-relationships existing among T790M mutation, activating EGFR mutations, HER2 amplification, and MET amplification. Paired samples of tumor and blood were obtained from a total of 18 patients with NSCLC after they had developed resistance to EGFR-TKI treatment, and the mechanisms of resistance were analyzed by digital PCR. Digital PCR analysis of T790M mutation in plasma had a sensitivity of 81.8% and specificity of 85.7%, the overall concordance between plasma and tissue samples being 83.3%. MET gene copy number gain in tumor DNA was observed by digital PCR in three patients, of whom one exhibited positivity for MET amplification by FISH, whereas no patient demonstrated MET and HER2 copy number gain in plasma DNA. Digital PCR analysis of plasma is feasible and accurate for detection of T790M mutation in NSCLC that becomes resistant to treatment with EGFR-TKIs.

Heterogeneity of anaplastic lymphoma kinase gene rearrangement in non-small-cell lung carcinomas: a comparative study between small biopsy and excision samples.

Introduction: The standard diagnostic method for echinoderm microtubule-associated protein-like 4-anaplastic lymphoma receptor tyrosine kinase translocation is fluorescence in situ hybridization (FISH). Recently, immunohistochemistry (IHC) has been reported as a potential method in screening for anaplastic lymphoma kinase (ALK)-positive non–small-cell lung carcinomas (NSCLC), whereas several authors have reported a discordance between FISH and IHC results. We investigated the heterogeneity of ALK gene rearrangement in excision specimens by FISH and also examined whether the FISH score of ALK gene rearrangement corresponded in excision and biopsy samples from the same patient. Methods: Twenty ALK IHC-positive patients including six patients treated with crizotinib therapy were evaluated for the presence of ALK FISH. For evaluation of heterogeneity of ALK gene rearrangement in excision specimens, we defined six to 10 observation areas in each case, and the number of ALK FISH positive observation areas (≥15% rearrangement detected) was investigated. ALK FISH score in small biopsy samples was classified as positive (≥15% rearrangement detected), equivocal (5–14% rearrangement detected), or negative (<4% rearrangement detected). Results: Of a total of 64 tumor observation areas from nine excision specimens, 50 areas were positive for ALK gene rearrangement (81.8%). In the comparison of excision and small biopsy samples, all excision specimens were ALK FISH-positive (100%; 6 of 6), whereas only three of the small biopsy samples in these patients were positive (50%; 3 of 6), two were equivocal (33%; 2 of 6), and one was negative (17%; 1 of 6). The two equivocal patients received crizotinib and showed a response. Conclusion: ALK gene rearrangement heterogeneity was observed in NSCLC specimens by FISH. Our findings suggested that IHC-positive/FISH-equivocal cases should not be considered true “false-negatives” when a small biopsy sample was used for ALK analysis.

Association of EGFR Exon 19 Deletion and EGFR-TKI Treatment Duration with Frequency of T790M Mutation in EGFR-Mutant Lung Cancer Patients

The most common event responsible for resistance to first- and second-generation (1st and 2nd) epidermal growth factor receptor (EGFR)-tyrosine kinase inhibitor (TKI) is acquisition of T790M mutation. We examined whether T790M is related to clinicopathologic or prognostic factors in patients with relapse of EGFR mutant non-small cell lung cancer (NSCLC) after treatment with 1st or 2nd EGFR-TKIs. We retrospectively reviewed the T790M status and clinical characteristics of 73 patients with advanced or recurrent NSCLC who had been treated with EGFR-TKIs and undergone rebiopsy at Kurume University Hospital between March 2005 and December 2015. T790M mutation was more frequent in patients with EGFR exon 19 deletion mutation (63%, 26/41) than in those with L858R mutation (38%, 12/32) (p = 0.035). The median total duration of 1st or 2nd EGFR-TKI treatment was significantly longer in patients with T790M mutation than in those without (15.3 months vs 8.1 months, p < 0.001). Multivariate analysis revealed that the type of EGFR mutation and the total duration of EGFR-TKI treatment were significantly associated with T790M prevalence. Patients with EGFR exon 19 deletion mutation who receive long-term EGFR-TKI therapy show a high prevalence of T790M mutation. The present data are potentially important for clinical decision-making in NSCLC patients with EGFR mutation.

Epidermal growth factor receptor mutation status in cell-free DNA supernatant of bronchial washings and brushings.

The aim of the current study was to examine whether it would be possible to detect epidermal growth factor receptor (EGFR) mutations in cytology cell‐free DNA (ccfDNA) from the supernatant fluids of bronchial cytology samples.

Programmed cell death-ligand 1 expression and immunoscore in stage II and III non-small cell lung cancer patients receiving adjuvant chemotherapy

Programmed cell death 1 (PD-1) receptor-ligand interaction is a major pathway that is often hijacked by tumors to suppress immune control. Immunoscore (IS), a combinational index of CD3 and CD8 tumor-infiltrating lymphocyte (TIL) density in the tumors center and invasive margin, is a new prognostic tool suggested to be superior to conventional tumor-staging methods in various tumors. This retrospective study aimed to investigate the prevalence and prognostic roles of PD-ligand 1 (PD-L1) expression and IS in non-small cell lung cancer (NSCLC) patients receiving adjuvant chemotherapy. PD-L1 expression and TIL density were evaluated by immunohistochemical analysis in 36 patients with stage II and III NSCLC. Tumors with staining in over 1% of their cells were scored as positive for PD-L1 expression, and we determined the median number of CD3- and CD8-positive TILs as the cutoff point for TIL density. To determine IS, each patient was given a binary score (0 for low and 1 for high) for CD3 and CD8 density in both the tumor center and invasive margin region. PD-L1 expression in tumor cells was observed in 61.1% (22/36) of patients. PD-L1 expression was significantly associated with high IS, and highest IS tended to have a favorable disease-free survival.Programmed cell death 1 (PD-1) receptor–ligand interaction is a major pathway that is often hijacked by tumors to suppress immune control. Immunoscore (IS), a combinational index of CD3 and CD8 tumor-infiltrating lymphocyte (TIL) density in the tumor’s center and invasive margin, is a new prognostic tool suggested to be superior to conventional tumor-staging methods in various tumors. This retrospective study aimed to investigate the prevalence and prognostic roles of PD-ligand 1 (PD-L1) expression and IS in non-small cell lung cancer (NSCLC) patients receiving adjuvant chemotherapy. PD-L1 expression and TIL density were evaluated by immunohistochemical analysis in 36 patients with stage II and III NSCLC. Tumors with staining in over 1% of their cells were scored as positive for PD-L1 expression, and we determined the median number of CD3- and CD8-positive TILs as the cutoff point for TIL density. To determine IS, each patient was given a binary score (0 for low and 1 for high) for CD3 and CD8 density in both the tumor center and invasive margin region. PD-L1 expression in tumor cells was observed in 61.1% (22/36) of patients. PD-L1 expression was significantly associated with high IS, and highest IS tended to have a favorable disease-free survival.

Accuracy of transbronchial biopsy as a rebiopsy method for patients with relapse of advanced non-small-cell lung cancer after systemic chemotherapy

Introduction Rebiopsy in patients with advanced non-small-cell lung cancer (NSCLC) resistant to systemic chemotherapy may yield information on the mechanisms of resistance and planning of subsequent treatment. Transbronchial biopsy (TBB) using a flexible bronchoscope has been commonly used for establishing the initial diagnosis of lung cancer. The aim of this study was to assess the accuracy and safety of TBB in patients with NSCLC relapse, and the factors affecting its diagnostic yield. Methods We retrospectively screened patients with advanced NSCLC who underwent TBB for rebiopsy after developing resistance to systemic chemotherapy at Kurume University Hospital between January 2012 and June 2016. A positive diagnostic result obtained by TBB was defined as malignancy determined on the basis of histological features that were adequate for mutational analysis or immunohistochemistry. Severe postprocedural complications were defined as those requiring invasive medical procedures or prolonged hospitalisation. Results 109 patients were enrolled in this retrospective study. Adequate tumour samples were collected from 88 of these patients, giving a high diagnostic yield of 80.7%. The diagnostic yield of TBB was not associated with tumour mutational status, the previous treatment regimen, or efficacy of the previous treatment. There were no severe postprocedural complications such as pneumothorax or serious haemorrhage. Conclusions TBB is considered one of the safest and most useful procedures for rebiopsy of NSCLC that has relapsed after chemotherapy, regardless of patient background and treatment history.

Predictive factors in patients with EGFR mutation‑negative non‑small cell lung cancer treated with erlotinib

Factors predicting the efficacy of erlotinib treatment in patients with EGFR mutation-negative non-small-cell lung cancer (NSCLC) have not been well studied. This retrospective study investigates whether patient characteristics, such as site of metastasis, can predict the efficacy of erlotinib treatment in NSCLC patients. In total, 53 EGFR mutation-negative NSCLC patients treated with erlotinib were enrolled, and the associations between clinicopathological characteristics and patient survival were analyzed. The EGFR mutation status was determined using the peptide nucleic acid-locked nucleic acid polymerase chain reaction clamp method. Survival curves were obtained using the Kaplan-Meier method. Among the NSCLC patients treated with erlotinib, 27 patients with pulmonary metastasis exhibited significantly longer progression-free survival (PFS) and overall survival (OS) times than those without pulmonary metastasis (median PFS time, 2.9 versus 1.2 months; P=0.0010 and median OS time, 12.4 versus 4.1 months; P=0.0007). Multivariate analyses also revealed that pulmonary metastasis independently correlated with PFS and OS times (hazard ratio, 0.39; P=0.0055 and hazard ratio, 0.33; P=0.0022, respectively). Patients with pulmonary metastasis exhibited significantly longer PFS and OS times than those without pulmonary metastasis. The presence of pulmonary metastasis may be a predictive factor in patients with EGFR mutation-negative NSCLC treated with erlotinib.

Phase II Trial of Carboplatin and Pemetrexed Plus Bevacizumab with Maintenance Bevacizumab as a First-line Treatment for Advanced Non-squamous Non-small Cell Lung Cancer in Elderly Patients

Background/Aim: The combination of platinum-doublet chemotherapy with bevacizumab has been established as a first-line treatment option in non-elderly patients with non-squamous (non-sq) non-small cell lung cancer (NSCLC). However, the safety and efficacy of this regimen have not yet been fully established in elderly patients. Patients and Methods: Chemo-naïve patients with non-sq NSCLC, aged ≥75 years, having a good performance status (Eastern Cooperative Oncology Group performance status 0-1) and adequate organ function were considered eligible. Patients received carboplatin (area under the curve=5 mg/ml/min), pemetrexed (500 mg/m2), and bevacizumab (15 mg/kg) every 3 weeks for up to 4 cycles, followed by maintenance bevacizumab. The primary endpoint was the objective response rate (ORR; target=50%, threshold=30%; Simons two-stage design), and the secondary endpoints were safety, progression-free survival (PFS), and overall survival (OS). Results: Twelve patients were enrolled from June 2013 to July 2017. The study was closed because of slow patient accrual. The median patient age was 80 years. Eleven patients (92%) completed 4 cycles of induction chemotherapy. Seven patients achieved a partial response (PR), yielding an ORR of 58%. The median PFS was 8.4 [95% confidence interval (CI)=4.4-10.5] months, and the median OS was 33.9 (95%CI=13.2-43.3) months. Toxicities were generally mild and consistent with previous reports. There were no treatment-related deaths. Conclusion: A regimen comprising carboplatin and pemetrexed plus bevacizumab followed by maintenance bevacizumab is feasible and potentially efficacious in elderly patients with non-sq NSCLC.