Madoka Kimura

The Risk of Cytotoxic Chemotherapy-Related Exacerbation of Interstitial Lung Disease with Lung Cancer

Introduction: It is unknown what type of interstitial lung disease (ILD) has high risk for chemotherapy-related exacerbation of ILD. We investigated the risk of exacerbation of ILD for patients with lung cancer with ILD. Methods: One hundred nine patients with lung cancer with ILD treated with cytotoxic chemotherapy at Shizuoka Cancer Center between August 2002 and April 2010 were retrospectively reviewed. Results: On pretreatment computed tomography (CT) of the chest, 69 patients (63%) were identified with usual interstitial pneumonia (UIP) pattern, and 40 patients (37%) had non-UIP pattern. Patients with UIP pattern developed cytotoxic chemotherapy-related exacerbation of ILD more frequently than those with non-UIP pattern (30 versus 8%, p = 0.005). The incidence of grade 5 pulmonary toxicities was 9% in patients with UIP pattern, compared with 3% in those with non-UIP pattern. Multivariate analyses demonstrated that age (<70 years) and CT pattern (UIP) were significant independent risk factors for cytotoxic chemotherapy-related exacerbation of ILD. In small cell lung cancer, overall survival (OS) from the start of first-line chemotherapy was significantly shorter in UIP pattern than non-UIP pattern (median OS: 9 versus 16 months, p = 0.0475), whereas there was no significant difference in patients with non-small cell lung cancer (median OS: 12 versus 9 months, p = 0.2529). Conclusions: Our results indicated that the incidence of exacerbation of ILD was significantly higher in patients with lung cancer with UIP pattern on CT findings than in those with non-UIP pattern. Therefore, great care is required when administering cytotoxic chemotherapy agents for patients with lung cancer with UIP pattern.

Diagnostic Accuracy of Noninvasive Genotyping of EGFR in Lung Cancer Patients by Deep Sequencing of Plasma Cell-Free DNA

BACKGROUND Genotyping of EGFR (epidermal growth factor receptor) mutations is indispensable for making therapeutic decisions regarding whether to use EGFR tyrosine kinase inhibitors (TKIs) for lung cancer. Because some cases might pose challenges for biopsy, noninvasive genotyping of EGFR in circulating tumor DNA (ctDNA) would be beneficial for lung cancer treatment. METHODS We developed a detection system for EGFR mutations in ctDNA by use of deep sequencing of plasma DNA. Mutations were searched in >100 000 reads obtained from each exon region. Parameters corresponding to the limit of detection and limit of quantification were used as the thresholds for mutation detection. We conducted a multi-institute prospective study to evaluate the detection system, enrolling 288 non-small cell lung cancer (NSCLC) patients. RESULTS In evaluating the performance of the detection system, we used the genotyping results from biopsy samples as a comparator: diagnostic sensitivity for exon 19 deletions, 50.9% (95% CI 37.9%-63.9%); diagnostic specificity for exon 19 deletions, 98.0% (88.5%-100%); sensitivity for the L858R mutation, 51.9% (38.7%-64.9%); and specificity for L858R, 94.1% (83.5%-98.6%). The overall sensitivities were as follows: all cases, 54.4% (44.8%-63.7%); stages IA-IIIA, 22.2% (11.5%-38.3%); and stages IIIB-IV, 72.7% (60.9%-82.1%). CONCLUSIONS Deep sequencing of plasma DNA can be used for genotyping of EGFR in lung cancer patients. In particular, the high specificity of the system may enable a direct recommendation for EGFR-TKI on the basis of positive results with plasma DNA. Because sensitivity was low in early-stage NSCLC, the detection system is preferred for stage IIIB-IV NSCLC.

Monitoring of treatment responses and clonal evolution of tumor cells by circulating tumor DNA of heterogeneous mutant EGFR genes in lung cancer

OBJECTIVES Epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs) have dramatic effects on EGFR-mutant non-small-cell lung cancer (NSCLC). However, most patients experience disease recurrences, approximately half of which are T790M-mediated. Monitoring EGFR status with re-biopsy has spatiotemporal limitations. PATIENTS AND METHODS EGFR circulating tumor DNA (ctDNA) in serial plasma samples was amplified and 10(5) of them were sequenced with a next-generation sequencer. Plasma mutation (PM) score was defined as the number of reads containing deletions/substitutions in 10(5)EGFR cell free DNA (cfDNA). RESULTS PM scores of various EGFR mutations showed dynamic, case-specific changes during EGFR-TKI treatments in 52 patients. The effects of the treatment on EGFR ctDNA were evaluated in 38 patients with elevated pre-treatment PM scores. The ctDNA responses correlated well with radiologic responses in radiologic good responders, whereas correlation was poor in non-responders. In addition to the peaks for the most prevalent ctDNA, small peaks of ctDNA with different types of activating EGFR mutations or the T790M mutation (early T790M ctDNA) appeared transiently in 10.5% and 26.3%, respectively. Early T790M ctDNA disappeared in all patients, including 7 who eventually developed acquired resistance accompanied by elevated levels of T790M ctDNA. CONCLUSIONS Monitoring ctDNA is useful in evaluating treatment responses and monitoring driver oncogene status in NSCLC. ctDNA revealed clonal heterogeneity and genetic processes of cancer evolution in individual patients. The simple presence of the T790M mutation may be insufficient to confer EGFR-TKI resistance to tumor cells.

Analysis of ERBB ligand-induced resistance mechanism to crizotinib by primary culture of lung adenocarcinoma with EML4-ALK fusion gene.

Introduction: Using cell line-based assays, the secretion of erythroblastic leukemia viral oncogene homologue (ERBB) ligands has been reported to contribute to resistance against crizotinib in lung cancer with the echinoderm microtubule-associated protein-like 4 and anaplastic lymphoma kinase fusion gene. However, it is difficult to predict the role of the ligands in each patient. Here, we report an analysis of the mechanism of resistance behind crizotinib resistance using a primary culture of cancer cells from pleural effusion of an anaplastic lymphoma kinase-positive lung cancer patient who was clinically resistant to crizotinib. Methods: Primary cancer cells were prepared as cancer tissue-originated spheroids (CTOSs) according to previously described methods. CTOSs were maintained in StemPro medium, and a sensitivity assay was performed under growth factor-free conditions, or under stimulation with epidermal growth factor (EGF) or neuregulin-1/heregulin. The effect of treatment with crizotinib alone or a combination of crizotinib and erlotinib was examined. Results: Cancer cells (LB53) were established to be CTOSs from a patient who was clinically resistant to crizotinib. The CTOSs were sensitive to crizotinib under growth factor-free conditions in vitro, whereas resistant under stimulation with EGF or neuregulin-1. These ligands rescued the inhibition of intracellular signaling by crizotinib. Pleural effusion from the patient also activated EGF receptor signaling to the similar extent of EGF stimulation. The resistance to crizotinib by EGF was reversed by blocking EGF receptor signaling by erlotinib in vitro. Conclusion: Stimulation by ERBB ligands is suggested to be responsible for resistance to crizotinib in this patient. The CTOS method may enable analysis of resistance mechanism for targeted therapy in individual patients.

Multiplexed Molecular Profiling of Lung Cancer Using Pleural Effusion

Introduction: Pleural effusion is frequently observed in patients with advanced lung cancer. Although effusion can be obtained less invasively and repeatedly, its use in multiplexed molecular profiling has not been fully investigated. Methods: Between July 2011 and April 2013, pleural effusion samples were obtained from patients with lung cancer at Shizuoka Cancer Center. They were analyzed for EGFR, KRAS, BRAF, PIK3CA, NRAS, MEK1, AKT1, PTEN, and HER2 mutations, EGFR, MET, FGFR1, FGFR2, and PIK3CA amplifications, and ALK, ROS1, and RET fusion genes using pyrosequensing and/or capillary electrophoresis, quantitative reverse-transcriptase polymerase chain reaction, and reverse-transcriptase polymerase chain reaction, respectively. Results: One hundred and two samples from 84 patients were analyzed. Adenocarcinoma was the most common histological subtype (82%). Genetic abnormalities were detected in 42% of patients. The most common abnormality was EGFR mutation (29%), followed by EML4-ALK rearrangement (5%), KRAS mutation, and EGFR amplification (4%, each). Concordance rates between pleural effusion and matched formalin-fixed, paraffin-embedded samples were 88%. Among 11 patients who provided samples at multiple time points, changes in molecular profile over the course of treatment were observed in five patients. Conclusions: The use of pleural effusion for multiplexed molecular testing and real-time monitoring in lung cancer was demonstrated.

Dynamics of circulating tumor DNA represented by the activating and resistant mutations in epidermal growth factor receptor tyrosine kinase inhibitor treatment.

Circulating tumor DNA (ctDNA) is an emerging field of cancer research. For lung cancer, non‐invasive genotyping of EGFR is the foremost application. The activating mutations represent the ctDNA from all cancer cells, and the T790M‐resistant mutation represents that from resistant cells. We examined the ctDNA dynamics of EGFR mutations by using deep sequencing with a massively parallel DNA sequencer. We obtained 190 plasma samples from 57 patients at various times during the treatment course and classified them according to treatment status. The mutation detection rate of exon 19 deletion/L858R in plasma was high at the initiation of treatment with epidermal growth factor receptor tyrosine kinase inhibitor (EGFR‐TKI; P = 0.001), suppressed during EGFR‐TKI treatment before disease progression, and elevated after the onset of disease progression (P = 0.023). The mutation detection rate of T790M was low until the onset of disease progression and elevated thereafter (P = 0.01). Samples across the development of disease progression were obtained from 10 patients and showed a correlation between increased ctDNA level and disease progression. Decreased ctDNA level in response to the initiation of EGFR‐TKI was observed in 4 of 6 eligible patients. In two patients, the ctDNA dynamics suggested the presence of cancer cell populations only with the T790M mutation. In another patient, the T790M ctDNA represented cell subpopulations that respond to cytotoxic agents differently from the major population. Considering the high incidence, ctDNA could be a clinical parameter to complement information from image analyses.

Numerical indices based on circulating tumor DNA for the evaluation of therapeutic response and disease progression in lung cancer patients.

Monitoring of disease/therapeutic conditions is an important application of circulating tumor DNA (ctDNA). We devised numerical indices, based on ctDNA dynamics, for therapeutic response and disease progression. 52 lung cancer patients subjected to the EGFR-TKI treatment were prospectively collected, and ctDNA levels represented by the activating and T790M mutations were measured using deep sequencing. Typically, ctDNA levels decreased sharply upon initiation of EGFR-TKI, however this did not occur in progressive disease (PD) cases. All 3 PD cases at initiation of EGFR-TKI were separated from other 27 cases in a two-dimensional space generated by the ratio of the ctDNA levels before and after therapy initiation (mutation allele ratio in therapy, MART) and the average ctDNA level. For responses to various agents after disease progression, PD/stable disease cases were separated from partial response cases using MART (accuracy, 94.7%; 95% CI, 73.5–100). For disease progression, the initiation of ctDNA elevation (initial positive point) was compared with the onset of objective disease progression. In 11 out of 28 eligible patients, both occurred within ±100 day range, suggesting a detection of the same change in disease condition. Our numerical indices have potential applicability in clinical practice, pending confirmation with designed prospective studies.

Early responses of EGFR circulating tumor DNA to EGFR tyrosine kinase inhibitors in lung cancer treatment

Objectives Early evaluation of the effect of treatment is helpful in the management of cancer patients. Circulating biomarkers are an ideal tool for this if they are highly specific to tumors and respond rapidly to tumor volume changes. Circulating tumor DNA (ctDNA) is one such candidate. We conducted a prospective study to test the utility of EGFR ctDNA in early evaluation of EGFR-TKI effects. Results Twenty-one patients with EGFR-mutant lung cancer who were naïve to EGFR-TKI were enrolled. PM scores of EGFR ctDNA with activating mutations decreased rapidly in response to EGFR-TKI. Of the 14 patients with positive pretreatment PM scores, complete disappearance of major EGFR ctDNA was observed in 14.3%, 42.9%, and 57.1% on days 2 – 4, 8, and 15, respectively. These responses of EGFR ctDNA were most prominent among the measures used to evaluate responses, and correlated with early radiologic responses evaluated by chest X-rays. Materials and methods EGFR ctDNA in serial plasma samples was amplified and 105 copies were sequenced with a next-generation sequencer. Plasma mutation (PM) score was defined as the number of reads containing deletions/substitutions in 105 EGFR cell free DNA (cfDNA). When EGFR mutation in ctDNA was the same as that detected in cancer tissue, the ctDNA was defined as major EGFR ctDNA. Conclusions The results indicate the usefulness of ctDNA as a highly specific biomarker for prediction of early response to treatment and that it can be applied to various types of cancer.

Delayed pseudoprogression of lung adenocarcinoma accompanied with interstitial lung disease during chemotherapy after nivolumab treatment

A 62‐year‐old Japanese female with primary lung adenocarcinoma received seven cycles of nivolumab as an eighth line of chemotherapy until she presented with hemoptysis. After transcatheter arterial embolization therapy, she received subsequent chemotherapy with paclitaxel and S−1. Four weeks later, a chest computed tomography examination revealed infiltrative shadows mainly in the right lung field, in addition to enlargement of the lung metastasis in the right middle lung lobe. Bronchofiberscopic examination revealed infiltration of lymphocytes without any malignant cells in the right segment 1 of the lung, which suggested interstitial lung disease. Corticosteroid therapy not only improved the infiltrative shadows but also reduced the lung metastasis. Even after the infiltrative shadows improved, the lung metastasis reduced further. This phenomenon resembles manifestation of pseudoprogression during treatments with immune checkpoint inhibitors, such as nivolumab.

HER3 expression is enhanced during progression of lung adenocarcinoma without EGFR mutation from stage 0 to IA1: Enhanced HER3 in stage IA1 lung ADC

Activating EGFR mutations, HER2, and HER3 are implicated in lung cancer; however, with the exception of EGFR gene amplification in lung adenocarcinoma harboring EGFR mutations, their involvement in disease progression during the early stages is poorly understood. In this paper, we focused on which receptor is correlated with lung adenocarcinoma progression in the presence or absence of EGFR mutation from stage 0 to IA1.