Influence of chemotherapy on EGFR mutation status among patients with non-small-cell lung cancer

Using Vision Transformer for high robustness and generalization in predicting EGFR mutation status in lung adenocarcinoma

BACKGROUND

Lung adenocarcinoma is a common cause of cancer-related deaths worldwide, and accurate EGFR genotyping is crucial for optimal treatment outcomes. Conventional methods for identifying the EGFR genotype have several limitations. Therefore, we proposed a deep learning model using non-invasive CT images to predict EGFR mutation status with robustness and generalizability.

METHODS

A total of 525 patients were enrolled at the local hospital to serve as the internal data set for model training and validation. In addition, a cohort of 30 patients from the publicly available Cancer Imaging Archive Data Set was selected for external testing. All patients underwent plain chest CT, and their EGFR mutation status labels were categorized as either mutant or wild type. The CT images were analyzed using a self-attention-based ViT-B/16 model to predict the EGFR mutation status, and the model's performance was evaluated. To produce an attention map indicating the suspicious locations of EGFR mutations, Grad-CAM was utilized.

RESULTS

The ViT deep learning model achieved impressive results, with an accuracy of 0.848, an AUC of 0.868, a sensitivity of 0.924, and a specificity of 0.718 on the validation cohort. Furthermore, in the external test cohort, the model achieved comparable performances, with an accuracy of 0.833, an AUC of 0.885, a sensitivity of 0.900, and a specificity of 0.800.

CONCLUSIONS

The ViT model demonstrates a high level of accuracy in predicting the EGFR mutation status of lung adenocarcinoma patients. Moreover, with the aid of attention maps, the model can assist clinicians in making informed clinical decisions.

GMILT: A Novel Transformer Network That Can Noninvasively Predict EGFR Mutation Status

Noninvasively and accurately predicting the epidermal growth factor receptor (EGFR) mutation status is a clinically vital problem. Moreover, further identifying the most suspicious area related to the EGFR mutation status can guide the biopsy to avoid false negatives. Deep learning methods based on computed tomography (CT) images may improve the noninvasive prediction of EGFR mutation status and potentially help clinicians guide biopsies by visual methods. Inspired by the potential inherent links between EGFR mutation status and invasiveness information, we hypothesized that the predictive performance of a deep learning network can be improved through extra utilization of the invasiveness information. Here, we created a novel explainable transformer network for EGFR classification named gated multiple instance learning transformer (GMILT) by integrating multi-instance learning and discriminative weakly supervised feature learning. Pathological invasiveness information was first introduced into the multitask model as embeddings. GMILT was trained and validated on a total of 512 patients with adenocarcinoma and tested on three datasets (the internal test dataset, the external test dataset, and The Cancer Imaging Archive (TCIA) public dataset). The performance (area under the curve (AUC) =0.772 on the internal test dataset) of GMILT exceeded that of previously published methods and radiomics-based methods (i.e., random forest and support vector machine) and attained a preferable generalization ability (AUC =0.856 in the TCIA test dataset and AUC =0.756 in the external dataset). A diameter-based subgroup analysis further verified the efficiency of our model (most of the AUCs exceeded 0.772) to noninvasively predict EGFR mutation status from computed tomography (CT) images. In addition, because our method also identified the "core area" of the most suspicious area related to the EGFR mutation status, it has the potential ability to guide biopsies.

AI-based pipeline for early screening of lung cancer: integrating radiology, clinical, and genomics data

Background

The prognosis of lung carcinoma has changed since the discovery of molecular targets and their specific drugs. Somatic Epidermal Growth Factor Receptor (EGFR) mutations have been reported in lung carcinoma, and these mutant proteins act as substrates for targeted therapies. However, in a resource-constrained country like India, panel-based next-generation sequencing cannot be made available to the population at large. Additional challenges such as adequacy of tissue in case of lung core biopsies and locating suitable tumour tissues as a result of innate intratumoral heterogeneity indicate the necessity of an AI-based end-to-end pipeline capable of automatically detecting and learning more effective lung nodule features from CT images and predicting the probability of the EGFR-mutant. This will help the oncologists and patients in resource-limited settings to achieve near-optimal care and appropriate therapy.

Methods

The EGFR gene sequencing and CT imaging data of 2277 patients with lung carcinoma were included from three cohorts in India and a White population cohort collected from TCIA. Another cohort LIDC-IDRI was used to train the AIPS-Nodule (AIPS-N) model for automatic detection and characterisation of lung nodules. We explored the value of combining the results of the AIPS-N with the clinical factors in the AIPS-Mutation (AIPS-M) model for predicting EGFR genotype, and it was evaluated by area under the curve (AUC).

Findings

AIPS-N achieved an average AP50 of 70.19% in detecting the location of nodules within the lung region of interest during validation and predicted the score of five lung nodule properties. The AIPS-M machine learning (ML) and deep learning (DL) models achieved AUCs ranging from 0.587 to 0.910.

Interpretation

The AIPS suggests that CT imaging combined with a fully automated lung-nodule analysis AI system can predict EGFR genotype and identify patients with an EGFR mutation in a cost-effective and non-invasive manner.

Funding

This work was supported by a grant provided by Conquer Cancer Foundation of ASCO [2021IIG-5555960128] and Pfizer Products India Pvt. Ltd.

Clinical characteristics and MRI based radiomics nomograms can predict iPFS and short-term efficacy of third-generation EGFR-TKI in EGFR-mutated lung adenocarcinoma with brain metastases

BACKGROUND

Predicting short-term efficacy and intracranial progression-free survival (iPFS) in epidermal growth factor receptor gene mutated (EGFR-mutated) lung adenocarcinoma patients with brain metastases who receive third-generation epidermal growth factor receptor tyrosine kinase inhibitor (EGFR-TKI) therapy was of great significance for individualized treatment. We aimed to construct and validate nomograms based on clinical characteristics and magnetic resonance imaging (MRI) radiomics for predicting short-term efficacy and intracranial progression free survival (iPFS) of third-generation EGFR-TKI in EGFR-mutated lung adenocarcinoma patients with brain metastases.

METHODS

One hundred ninety-four EGFR-mutated lung adenocarcinoma patients with brain metastases who received third-generation EGFR-TKI treatment were included in this study from January 1, 2017 to March 1, 2023. Patients were randomly divided into training cohort and validation cohort in a ratio of 5:3. Radiomics features extracted from brain MRI were screened by least absolute shrinkage and selection operator (LASSO) regression. Logistic regression analysis and Cox proportional hazards regression analysis were used to screen clinical risk factors. Single clinical (C), single radiomics (R), and combined (C + R) nomograms were constructed in short-term efficacy predicting model and iPFS predicting model, respectively. Prediction effectiveness of nomograms were evaluated by calibration curves, Harrell's concordance index (C-index), receiver operating characteristic (ROC) curves and decision curve analysis (DCA). Kaplan-Meier analysis was used to compare the iPFS of high and low iPFS rad-score patients in the predictive iPFS R model and to compare the iPFS of high-risk and low-risk patients in the predictive iPFS C + R model.

RESULTS

Overall response rate (ORR) was 71.1%, disease control rate (DCR) was 91.8% and median iPFS was 12.67 months (7.88-20.26, interquartile range [IQR]). There were significant differences in iPFS between patients with high and low iPFS rad-scores, as well as between high-risk and low-risk patients. In short-term efficacy model, the C-indexes of C + R nomograms in training cohort and validation cohort were 0.867 (0.835-0.900, 95%CI) and 0.803 (0.753-0.854, 95%CI), while in iPFS model, the C-indexes were 0.901 (0.874-0.929, 95%CI) and 0.753 (0.713-0.793, 95%CI).

CONCLUSIONS

The third-generation EGFR-TKI showed significant efficacy in EGFR-mutated lung adenocarcinoma patients with brain metastases, and the combined line plot of C + R can be utilized to predict short-term efficacy and iPFS.

Joint analysis of mutational and transcriptional landscapes in human cancer reveals key perturbations during cancer evolution

BACKGROUND

Tumors are able to acquire new capabilities, including traits such as drug resistance and metastasis that are associated with unfavorable clinical outcomes. Single-cell technologies have made it possible to study both mutational and transcriptomic profiles, but as most studies have been conducted on model systems, little is known about cancer evolution in human patients. Hence, a better understanding of cancer evolution could have important implications for treatment strategies.

RESULTS

Here, we analyze cancer evolution and clonal selection by jointly considering mutational and transcriptomic profiles of single cells acquired from tumor biopsies from 49 lung cancer samples and 51 samples with chronic myeloid leukemia. Comparing the two profiles, we find that each clone is associated with a preferred transcriptional state. For metastasis and drug resistance, we find that the number of mutations affecting related genes increases as the clone evolves, while changes in gene expression profiles are limited. Surprisingly, we find that mutations affecting ligand-receptor interactions with the tumor microenvironment frequently emerge as clones acquire drug resistance.

CONCLUSIONS

Our results show that lung cancer and chronic myeloid leukemia maintain a high clonal and transcriptional diversity, and we find little evidence in favor of clonal sweeps. This suggests that for these cancers selection based solely on growth rate is unlikely to be the dominating driving force during cancer evolution.

Transfer learning-based PET/CT three-dimensional convolutional neural network fusion of image and clinical information for prediction of EGFR mutation in lung adenocarcinoma

BACKGROUND

To introduce a three-dimensional convolutional neural network (3D CNN) leveraging transfer learning for fusing PET/CT images and clinical data to predict EGFR mutation status in lung adenocarcinoma (LADC).

METHODS

Retrospective data from 516 LADC patients, encompassing preoperative PET/CT images, clinical information, and EGFR mutation status, were divided into training (n = 404) and test sets (n = 112). Several deep learning models were developed utilizing transfer learning, involving CT-only and PET-only models. A dual-stream model fusing PET and CT and a three-stream transfer learning model (TS_TL) integrating clinical data were also developed. Image preprocessing includes semi-automatic segmentation, resampling, and image cropping. Considering the impact of class imbalance, the performance of the model was evaluated using ROC curves and AUC values.

RESULTS

TS_TL model demonstrated promising performance in predicting the EGFR mutation status, with an AUC of 0.883 (95%CI = 0.849-0.917) in the training set and 0.730 (95%CI = 0.629-0.830) in the independent test set. Particularly in advanced LADC, the model achieved an AUC of 0.871 (95%CI = 0.823-0.919) in the training set and 0.760 (95%CI = 0.638-0.881) in the test set. The model identified distinct activation areas in solid or subsolid lesions associated with wild and mutant types. Additionally, the patterns captured by the model were significantly altered by effective tyrosine kinase inhibitors treatment, leading to notable changes in predicted mutation probabilities.

CONCLUSION

PET/CT deep learning model can act as a tool for predicting EGFR mutation in LADC. Additionally, it offers clinicians insights for treatment decisions through evaluations both before and after treatment.

Intratumoral Heterogeneity in Lung Cancer

The diagnosis and treatment of lung cancer (LC) is always a challenge. The difficulty in the decision of therapeutic schedule and diagnosis is directly related to intratumoral heterogeneity (ITH) in the progression of LC. It has been proven that most tumors emerge and evolve under the pressure of their living microenvironment, which involves genetic, immunological, metabolic, and therapeutic components. While most research on ITH revealed multiple mechanisms and characteristic, a systemic exposition of ITH in LC is still hard to find. In this review, we describe how ITH in LC develops from the perspective of space and time. We discuss elaborate details and affection of every aspect of ITH in LC and the relationship between them. Based on ITH in LC, we describe a more accurate multidisciplinary therapeutic strategy on LC and provide the newest opinion on the potential approach of LC therapy.

Predicting EGFR mutation, ALK rearrangement, and uncommon EGFR mutation in NSCLC patients by driverless artificial intelligence: a cohort study

Background

Timely identification of epidermal growth factor receptor (EGFR) mutation and anaplastic lymphoma kinase (ALK) rearrangement status in patients with non-small cell lung cancer (NSCLC) is essential for tyrosine kinase inhibitors (TKIs) administration. We aimed to use artificial intelligence (AI) models to predict EGFR mutations and ALK rearrangement status using common demographic features, pathology and serum tumor markers (STMs).

Methods

In this single-center study, demographic features, pathology, EGFR mutation status, ALK rearrangement, and levels of STMs were collected from Wuhan Union Hospital. One retrospective set (N = 1089) was used to train diagnostic performance using one deep learning model and five machine learning models, as well as the stacked ensemble model for predicting EGFR mutations, uncommon EGFR mutations, and ALK rearrangement status. A consecutive testing cohort (n = 1464) was used to validate the predictive models.

Results

The final AI model using the stacked ensemble yielded optimal diagnostic performance with areas under the curve (AUC) of 0.897 and 0.883 for predicting EGFR mutation status and 0.995 and 0.921 for predicting ALK rearrangement in the training and testing cohorts, respectively. Furthermore, an overall accuracy of 0.93 and 0.83 in the training and testing cohorts, respectively, were achieved in distinguishing common and uncommon EGFR mutations, which were key evidence in guiding TKI selection.

Conclusions

In this study, driverless AI based on robust variables could help clinicians identify EGFR mutations and ALK rearrangement status and provide vital guidance in TKI selection for targeted therapy in NSCLC patients.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12931-022-02053-2.

Field carcinogenesis and biological significance of the potential of the bystander effect: carcinogenesis, therapeutic response, and tissue regeneration

The "bystander effect" is a transmission phenomenon mediating communication from target to non-target cells, as well as cell-to-cell interactions between neighboring and distantly located cells. In this narrative review, we describe the fundamental and clinical significance of the bystander effect with respect to cell-to-cell interactions in carcinogenesis, therapeutic response, and tissue regeneration. In carcinogenesis, the bystander effect mediates communications between tumor microenvironments and non-malignant epithelial cells and has been suggested to impact heterogeneous tumorigenic cells in tumors and cancerized fields. In therapeutic response, the bystander effect mediates communications between drug-sensitive and drug-resistant cells and may transmit both drug efficacy and resistance. Therefore, control of therapeutic response transmission via the bystander effect might offer a promising future cancer treatment. Finally, in tissue regeneration, circulating cells and stromal cells may differentiate into various cells for the purpose of tissue regeneration under direction of the bystander effect arising from surrounding cells in a defective space. We hope that the findings we present will promote the development of innovative cancer therapies and tissue regeneration methodologies from the viewpoint of cell-to-cell interactions through the bystander effect.

A Review of the Correlation Between Epidermal Growth Factor Receptor Mutation Status and 18F-FDG Metabolic Activity in Non-Small Cell Lung Cancer

PET/CT with 18F-2-fluoro-2-deoxyglucose (18F-FDG) has been proposed as a promising modality for diagnosing and monitoring treatment response and evaluating prognosis for patients with non-small cell lung cancer (NSCLC). The status of epidermal growth factor receptor (EGFR) mutation is a critical signal for the treatment strategies of patients with NSCLC. Higher response rates and prolonged progression-free survival could be obtained in patients with NSCLC harboring EGFR mutations treated with tyrosine kinase inhibitors (TKIs) when compared with traditional cytotoxic chemotherapy. However, patients with EGFR mutation treated with TKIs inevitably develop drug resistance, so predicting the duration of resistance is of great importance for selecting individual treatment strategies. Several semiquantitative metabolic parameters, e.g., maximum standard uptake value (SUVmax), metabolic tumor volume (MTV), and total lesion glycolysis (TLG), measured by PET/CT to reflect 18F-FDG metabolic activity, have been demonstrated to be powerful in predicting the status of EGFR mutation, monitoring treatment response of TKIs, and assessing the outcome of patients with NSCLC. In this review, we summarize the biological and clinical correlations between EGFR mutation status and 18F-FDG metabolic activity in NSCLC. The metabolic activity of 18F-FDG, as an extrinsic manifestation of NSCLC, could reflect the mutation status of intrinsic factor EGFR. Both of them play a critical role in guiding the implementation of treatment modalities and evaluating therapy efficacy and outcome for patients with NSCLC.

The genomic landscape of metastatic clear cell renal cell carcinoma after systemic therapy

Primary clear cell renal cell carcinoma (ccRCC) has been previously characterized, but the genomic landscape of metastatic ccRCC is largely unexplored. Here, we performed whole exome sequencing (WES) in 68 samples from 44 patients with ccRCC, including 52 samples from a metastatic site. SETD2, PBRM1, APC and VHL were the most frequently mutated genes in the metastatic ccRCC cohort. RBM10 and FBXW7 were also among the 10 most frequently mutated genes in metastatic tissues. Recurrent somatic copy number variations (CNV) were observed at the previously identified regions 3p25, 9p21 and 14q25, but also at 6p21 (CDKN1A) and 13q14 (RB1). No statistically significant differences were found between samples from therapy‐naïve and pretreated patients. Clonal evolution analyses with multiple samples from 13 patients suggested that early appearance of CNVs at 3p25, 9p21 and 14q25 may be associated with rapid clinical progression. Overall, the genomic landscapes of primary and metastatic ccRCC seem to share frequent CNVs at 3p25, 9p21 and 14q25. Future work will clarify the implication of RBM10 and FBXW7 mutations and 6p21 and 13q14 CNVs in metastatic ccRCC.

Conversion from Positive to Negative EGFR Mutation due to Clonal Selection during Long-Term Treatment with Epidermal Growth Factor Receptor-Tyrosine Kinase Inhibitors: A Case Report

A 77-year-old woman with postoperative recurrent non-small cell lung adenocarcinoma, which exhibited an epidermal growth factor receptor (EGFR) L858R mutation, was treated with gefitinib and erlotinib. Seven years after the start of treatment, the patient experienced a recurrence of malignant pleural effusion. However, 3 different genetic tests revealed that the lung adenocarcinoma cells in the pleural effusion had lost EGFR L858R mutation, suggesting that long-term treatment with EGFR-tyrosine kinase inhibitors (TKIs) converted EGFR mutation from positive to negative. The negative conversion of EGFR mutation as a mechanism of acquired resistance to EGFR-TKIs is considered rare and needs to be further investigated.

Efficacy and acquired resistance of EGFR-TKI combined with chemotherapy as first-line treatment for Chinese patients with advanced non-small cell lung cancer in a real-world setting

Background

To compare the benefits and explore the cause of acquired resistance of epidermal growth factor receptor tyrosine kinase inhibitor (EGFR-TKI) and its combination with chemotherapy in advanced non-small-cell lung cancer (NSCLC) patients harboring EGFR mutation in a real-life setting.

Methods

This retrospective analysis included 117 advanced NSCLC patients with EGFR mutation who underwent next-generation sequencing (NGS) prior to treatment. The combination group included 50 patients who received the regimen of EGFR-TKI combined with chemotherapy, while the EGFR-TKI monotherapy group included 67 patients treated with TKI only. The primary endpoint of this study was progression-free survival (PFS); the secondary endpoints were overall survival (OS), response rate, and toxicity.

Results

The median PFS was significantly longer in the combination group than in the EGFR-TKI monotherapy group (19.00 months [95% CI, 14.67–23.33] vs. 11.70 months [95% CI, 10.81–12.59], p < 0.001). Subgroup analysis showed a similar trend of results. The median OS was not reached in the combination group and was 38.50 (95% CI, 35.30–41.70) months in the EGFR-TKI monotherapy group (p = 0.586). Patients in the combination group were more likely to experience adverse events, most of which showed the severity of grade 1 or 2. T790M mutation remains the main reason for acquired resistance, and the frequency of T790M mutation was similar between the two groups (p = 0.898).

Conclusions

Compared with EGFR-TKI monotherapy, EGFR-TKI combined with chemotherapy significantly improved PFS in advanced NSCLC patients with EGFR mutation, with acceptable toxicity.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12885-021-08291-9.

Artificial Intelligence in Cancer Research and Precision Medicine

Artificial intelligence (AI) is rapidly reshaping cancer research and personalized clinical care. Availability of high-dimensionality datasets coupled with advances in high-performance computing, as well as innovative deep learning architectures, has led to an explosion of AI use in various aspects of oncology research. These applications range from detection and classification of cancer, to molecular characterization of tumors and their microenvironment, to drug discovery and repurposing, to predicting treatment outcomes for patients. As these advances start penetrating the clinic, we foresee a shifting paradigm in cancer care becoming strongly driven by AI. SIGNIFICANCE: AI has the potential to dramatically affect nearly all aspects of oncology-from enhancing diagnosis to personalizing treatment and discovering novel anticancer drugs. Here, we review the recent enormous progress in the application of AI to oncology, highlight limitations and pitfalls, and chart a path for adoption of AI in the cancer clinic.

Non-invasive decision support for NSCLC treatment using PET/CT radiomics

Two major treatment strategies employed in non-small cell lung cancer, NSCLC, are tyrosine kinase inhibitors, TKIs, and immune checkpoint inhibitors, ICIs. The choice of strategy is based on heterogeneous biomarkers that can dynamically change during therapy. Thus, there is a compelling need to identify comprehensive biomarkers that can be used longitudinally to help guide therapy choice. Herein, we report a 18F-FDG-PET/CT-based deep learning model, which demonstrates high accuracy in EGFR mutation status prediction across patient cohorts from different institutions. A deep learning score (EGFR-DLS) was significantly and positively associated with longer progression free survival (PFS) in patients treated with EGFR-TKIs, while EGFR-DLS is significantly and negatively associated with higher durable clinical benefit, reduced hyperprogression, and longer PFS among patients treated with ICIs. Thus, the EGFR-DLS provides a non-invasive method for precise quantification of EGFR mutation status in NSCLC patients, which is promising to identify NSCLC patients sensitive to EGFR-TKI or ICI-treatments.

Effective Treatment With Afatinib of Lung Adenocarcinoma With Leptomeningeal Metastasis Harboring the Exon 18 p.G719A Mutation in the EGFR Gene Was Detected in Cerebrospinal Fluid: A Case Report

Background: In patients with lung adenocarcinoma and leptomeningeal metastases, it remains unknown whether non-classical mutations in the epidermal growth factor receptor (EGFR) gene can be detected in the cerebrospinal fluid (CSF) and how it may be used to design directed therapy.

Methods: On April 18, 2018, the Interventional Department of Tianjin Huanhu Hospital admitted a 34-years-old male patient with lung adenocarcinoma and leptomeningeal metastasis. An emergency lateral ventriculoperitoneal shunt was performed to relieve the clinical symptoms of intracranial hypertension. Next-generation sequencing (NGS) of the CFS specimens revealed a mutation in EGFR exon 18 p.G719A, and afatinib was administered. Follow-up showed significantly relieved headache, with significantly reduced soft leptomeningeal abnormal enhancement as revealed by enhanced magnetic resonance imaging and significantly smaller tumors in the left lung by chest computed tomography. Carcinoembryonic antigens (CEAs) in cerebrospinal fluid and peripheral blood were significantly reduced. The patient responded well to afatinib, with mild adverse complications. The patient died on October 27, 2019 from respiratory failure as a result of lung infection unrelated to cancer progression. The overall survival (OS) using afatinib was 530 days.

Conclusion: CSF can be used as a liquid biopsy for NGS gene detection in patients with lung adenocarcinoma and leptomeningeal metastases. Afatinib exhibits a beneficial effect in patients with lung adenocarcinoma and leptomeningeal metastases harboring the EGFR exon 18 p.G719A mutation.

Smoking habit and chemo-radiotherapy and/or surgery affect the sensitivity of EGFR plasma test in non-small cell lung cancer

OBJECTIVE

This study aimed to identify the influential factors for the sensitivity of epidermal growth factor receptor (EGFR) plasma test in non-small cell lung cancer (NSCLC). The mutations were detected in tumor tissue and matched plasma samples from 125 newly diagnosed adenocarcinoma, clinical-stage IIIB-IV patients, and compared the diagnostic values of EGFR plasma test between groups of clinical characteristics. The influential factors for the sensitivity were identified and assessed by logistic regression.

RESULTS

EGFR mutations were detected in 65 (52.0%) tumor tissue and 50 (40.0%) matched plasma samples (P = 0.028). Compared to the tissue method, the concordance rate, sensitivity, and specificity of the EGFR plasma test were 86.4%, 75.4%, and 98.3%, respectively. Notably, we found that sensitivity of the test is higher in non-smokers (84.1%) compared to smokers (57.1%, P = 0.018), and in treatment naïve subjects (85.7%) compared to whom undergone chemo-radiotherapy with/without surgery before testing (56.5%, P = 0.009). Furthermore, the highest sensitivity was attained in patients without these two factors (90.3%), whilst the lowest value was noted in those with both factors (40.0%, P = 0.004). The multivariable analysis confirmed that smoking habit and treatment history have independently negative impacts on sensitivity (OR = 0.24, P = 0.019, and OR = 0.36, P = 0.047, respectively).

Gefitinib Versus Gefitinib Plus Pemetrexed and Carboplatin Chemotherapy in EGFR-Mutated Lung Cancer

PURPOSE

Standard first-line therapy for EGFR-mutant advanced non-small-cell lung cancer (NSCLC) is an epidermal growth factor receptor (EGFR)-directed oral tyrosine kinase inhibitor. Adding pemetrexed and carboplatin chemotherapy to an oral tyrosine kinase inhibitor may improve outcomes.

PATIENTS AND METHODS

This was a phase III randomized trial in patients with advanced NSCLC harboring an EGFR-sensitizing mutation and a performance status of 0 to 2 who were planned to receive first-line palliative therapy. Random assignment was 1:1 to gefitinib 250 mg orally per day (Gef) or gefitinib 250 mg orally per day plus pemetrexed 500 mg/m² and carboplatin area under curve 5 intravenously every 3 weeks for four cycles, followed by maintenance pemetrexed (gefitinib plus chemotherapy [Gef+C]). The primary end point was progression-free survival (PFS); secondary end points included overall survival (OS), response rate, and toxicity.

RESULTS

Between 2016 and 2018, 350 patients were randomly assigned to Gef (n = 176) and Gef+C (n = 174). Twenty-one percent of patients had a performance status of 2, and 18% of patients had brain metastases. Median follow-up time was 17 months (range, 7 to 30 months). Radiologic response rates were 75% and 63% in the Gef+C and Gef arms, respectively (P = .01). Estimated median PFS was significantly longer with Gef+C than Gef (16 months [95% CI, 13.5 to 18.5 months] v 8 months [95% CI, 7.0 to 9.0 months], respectively; hazard ratio for disease progression or death, 0.51 [95% CI, 0.39 to 0.66]; P < .001). Estimated median OS was significantly longer with Gef+C than Gef (not reached v 17 months [95% CI, 13.5 to 20.5 months]; hazard ratio for death, 0.45 [95% CI, 0.31 to 0.65]; P < .001). Clinically relevant grade 3 or greater toxicities occurred in 51% and 25% of patients in the Gef+C and Gef arms, respectively (P < .001).

CONCLUSION

Adding pemetrexed and carboplatin chemotherapy to gefitinib significantly prolonged PFS and OS but increased toxicity in patients with NSCLC.

Saliva-derived cfDNA is applicable for EGFR mutation detection but not for quantitation analysis in non-small cell lung cancer

Background

Both quantitative and qualitative aspects of plasma cell‐free DNA (plasma cfDNA, pcfDNA) have been well‐studied as potential biomarkers in non‐small cell lung cancer (NSCLC). Accumulating evidence has proven that saliva also has the potential for the detection and analysis of circulating free DNA (saliva cfDNA, scfDNA).

Methods

In the current study, we aimed to explore the potential application of scfDNA in NSCLC diagnostics and consistency of epidermal growth factor receptor (EGFR) mutation detection in paired pcfDNA and scfDNA using droplet digital PCR (ddPCR) and analyze the relationship between EGFR mutations and clinical treatment response.

Results

In the quantitative cohort study, scfDNA concentration in NSCLC patients was no different from that in healthy donors, or in benign patients. ScfDNA concentration was significantly lower than pcfDNA concentration, yet they were not statistically significant in relevance (Spearman's rank correlation r = −0.123, P = 0.269). In the qualitative cohort study, the overall concordance rate of EGFR mutations between pcfDNA and scfDNA was 83.78% (31 of 37; k = 0.602; P < 0.001). EGFR mutation detection in paired pcfDNA and scfDNA was significantly correlated with the clinical treatment response (Spearman's rank correlation r = 0.664, P = 0.002).

Conclusions

Our results demonstrated that saliva might not be the idea material for a cfDNA quantitative test, and scfDNA concentration is not applicable for NSCLC diagnostics. Conversely, scfDNA was capable of acting as the supplement for EGFR mutations due to the coincidence rate of EGFR mutation detection between scfDNA and pcfDNA.

Detection of Plasma EGFR Mutations in NSCLC Patients with a Validated ddPCR Lung cfDNA Assay

Purpose: The clinical utility of cell-free DNA (cfDNA) to assess EGFR mutations is increasing. However, there are limited studies determining their clinical validity and utility. The value of cfDNA assays in cancer management remains controversial. Methods: In this study, we first evaluated the analytical performance of the ddPCR Lung cfDNA Assay. We next analyzed the concordance of the results with tissue amplification refractory mutation system PCR (ARMS-PCR) and plasma next-generation sequencing (NGS) genotyping. Finally, we assessed its clinical utility by exploring the association of cfDNA EGFR mutations with metastatic sites and the efficacy of EGFR-TKIs treatment. Results: The ddPCR Lung cfDNA Assay demonstrated a limit of blank of 1 droplet per reaction, an analytical specificity of 100%, and detection limit of 0.05%, 0.05%, and 0.1% for E746_A750del, L858R, and T790M, respectively. With tissue ARMS-PCR as a standard for comparison, the clinical sensitivity and specificity of ddPCR were 62.5% (15/24) and 100% (82/82) for E746_A750del, and 75.0% (15/20) and 94.2% (81/86) for L858R, respectively. The ddPCR showed high concordance with NGS in determining cfDNA EGFR mutations. Patients with bone and/or brain metastasis showed a higher detection rate and mutant abundance of cfDNA EGFR mutations compared to those with other sites of metastasis. Moreover, EGFR-TKIs treatment was effective in patients with sensitive EGFR mutations in either plasma cfDNA or tumor tissue-derived DNA. Conclusions: We validated in this study that the ddPCR Lung cfDNA Assay is reliable for detection of EGFR mutations in lung cancers, in terms of analytical performance, clinical validity and utility.

Liquid biopsy for lung cancer immunotherapy

The recent successful use of the immune checkpoint inhibitors (CPIs) anti-programmed death receptor-1 (PD-1)/PD-1 ligand 1 in clinical trials indicates their crucial role in obtaining an effective cancer immune therapy. These CPIs have been identified to have an effective therapeutic response, particularly in tumors with high tumor mutation burden. Targeting private somatic mutations encoding immunogenic neoantigens (neo-Ags) has been developed as an autologous gene therapy. T-cell receptor-engineered T cells targeting neo-Ags are a novel option for adoptive cell therapy used for the treatment of lung cancer. However, not all patients experience an effective response from immunotherapy. Although the resistance mechanism of CPIs has been reported, its association with other treatment methods during systemic anticancer therapy remains unclear, particularly the treatment options following the emergence of drug resistance in lung cancer. The potential biomarkers used for liquid biopsy may assist in the identification of patients who would benefit the most from immunotherapy. Attempts to identify potential biomarkers for predicting clinical response to immunotherapy are underway. With regard to liquid biopsy, the present review summarizes and discusses the lung cancer management of immunotherapy for precision medicine by reviewing recent literature and associated clinical trials.

Tumour biomarkers-Tracing the molecular function and clinical implication

In recent years, with the increase in cancer mortality caused by metastasis, and with the development of individualized and precise medical treatment, early diagnosis with precision becomes the key to decrease the death rate. Since detecting tumour biomarkers in body fluids is the most non‐invasive way to identify the status of tumour development, it has been widely investigated for the usage in clinic. These biomarkers include different expression or mutation in microRNAs (miRNAs), circulating tumour DNAs (ctDNAs), proteins, exosomes and circulating tumour cells (CTCs). In the present article, we summarized and discussed some updated research on these biomarkers. We overviewed their biological functions and evaluated their multiple roles in human and small animal clinical treatment, including diagnosis of cancers, classification of cancers, prognostic and predictive values for therapy response, monitors for therapy efficacy, and anti‐cancer therapeutics. Biomarkers including different expression or mutation in miRNAs, ctDNAs, proteins, exosomes and CTCs provide more choice for early diagnosis of tumour detection at early stage before metastasis. Combination detection of these tumour biomarkers may provide higher accuracy at the lowest molecule combination number for tumour early detection. Moreover, tumour biomarkers can provide valuable suggestions for clinical anti‐cancer treatment and execute monitoring of treatment efficiency.

Dynamic molecular analysis and clinical correlates of tumor evolution within a phase II trial of panitumumab-based therapy in metastatic colorectal cancer

Background

Mutations in rat sarcoma (RAS) genes may be a mechanism of secondary resistance in epidermal growth factor receptor inhibitor-treated patients. Tumor-tissue biopsy testing has been the standard for evaluating mutational status; however, plasma testing of cell-free DNA has been shown to be a more sensitive method for detecting clonal evolution.

Materials and methods

Archival pre- and post-treatment tumor biopsy samples from a phase II study of panitumumab in combination with irinotecan in patients with metastatic colorectal cancer (mCRC) that also collected plasma samples before, during, and after treatment were analyzed for emergence of mutations during/post-treatment by next-generation sequencing and BEAMing.

Results

The rate of emergence of tumor tissue RAS mutations was 9.5% by next-generation sequencing (n = 21) and 6.3% by BEAMing (n = 16). Plasma testing of cell-free DNA by BEAMing revealed a mutant RAS emergence rate of 36.7% (n = 39). Exploratory outcomes analysis of plasma samples indicated that patients who had emergent RAS mutations at progression had similar median progression-free survival to those patients who remained wild-type at progression. Serial analysis of plasma samples showed that the first detected emergence of RAS mutations preceded progression by a median of 3.6 months (range, −0.3 to 7.5 months) and that there did not appear to be a mutant RAS allele frequency threshold that could predict near-term outcomes.

Conclusions

This first prospective analysis in mCRC showed that serial plasma biopsies are more inclusive than tissue biopsies for evaluating global tumor heterogeneity; however, the clinical utility of plasma testing in mCRC remains to be further explored.

ClinicalTrials.gov Identifier

NCT00891930

The emerging role of cell-free DNA as a molecular marker for cancer management

An increasing number of studies demonstrate the potential use of cell-free DNA (cfDNA) as a surrogate marker for multiple indications in cancer, including diagnosis, prognosis, and monitoring. However, harnessing the full potential of cfDNA requires (i) the optimization and standardization of preanalytical steps, (ii) refinement of current analysis strategies, and, perhaps most importantly, (iii) significant improvements in our understanding of its origin, physical properties, and dynamics in circulation. The latter knowledge is crucial for interpreting the associations between changes in the baseline characteristics of cfDNA and the clinical manifestations of cancer. In this review we explore recent advancements and highlight the current gaps in our knowledge concerning each point of contact between cfDNA analysis and the different stages of cancer management.

First-line tyrosine kinase inhibitors in EGFR mutation-positive non-small-cell lung cancer: a network meta-analysis

BACKGROUND

EGFR-tyrosine kinase inhibitors (EGFR-TKIs) including afatinib, dacomitinib, erlotinib, gefitinib, and osimertinib have proven efficacy in terms of progression-free survival (PFS) in patients with non-small-cell lung cancer (NSCLC) harboring EGFR mutations. However, an overall view for comparing efficacy and toxicity on a meta-level is lacking. This study compared efficacy and toxicity of first-line treatment with five different EGFR-TKIs by conducting a network meta-analysis (NMA).

METHODS

A systematic review was performed, aiming to find eligible literature. Data of PFS, overall survival (OS), objective response rate (ORR), and adverse events were extracted. An NMA based on Bayesian statistics was established to synthesize the efficacy and toxicity of all treatments.

RESULTS

Thirteen randomized controlled trials, including data from 3,539 patients with EGFR-mutated NSCLC, were analyzed. Rank probabilities showed that osimertinib had a potentially better efficacy in terms of PFS and OS compared to all other TKIs. For ORR, afatinib and osimertinib showed a trend of superiority compared to the other four TKIs. Furthermore, there was a high risk of diarrhea and rash for patients treated with afatinib or dacomitinib as well as a moderate risk for treatment with erlotinib, gefitinib, and osimertinib.

CONCLUSION

Our study showed a favorable efficacy of osimertinib in terms of PFS and OS compared to all other EGFR-TKIs in patients with NSCLC harboring activating EGFR mutations. Furthermore, gefitinib, erlotinib, and osimertinib were associated with fewer toxicities compared to the other TKIs. Therefore, osimertinib is indicated as a preferable first-line TKI in patients with activating EGFR-mutated NSCLC.

Technical and Regulatory Considerations for Taking Liquid Biopsy to the Clinic: Validation of the JAX PlasmaMonitorTM Assay

The standard of care in oncology has been genomic profiling of tumor tissue biopsies for the treatment and management of disease, which can prove to be quite challenging in terms of cost, invasiveness of procedure, and potential risk for the patient. As the number of available drugs in oncology continues to increase, so too does the demand for technologies and testing applications that can identify genomic alterations targetable by these new therapies. Liquid biopsies that use a blood draw from the diseased patient may offset the many disadvantages of the invasive procedure. However, as with any new technology or finding in the clinical field, the clinical utility of an analytical test such as that of the liquid biopsy has to be established. Here, we review the clinical testing space for liquid biopsy offerings and elucidate the technical and regulatory considerations to develop such an assay, using our recently validated PlasmaMonitor^TM test.

Elevation of tumor mutation burden in ROS1-fusion lung adenocarcinoma resistant to crizotinib: A case report

RATIONALE

Although most of non-small cell lung cancer (NSCLC) patients with ROS1-fusions respond to crizotinb, acquired resistance eventually develop. The next-generations of ROS1 inhibitors have made some achievements, but the effects of immunotherapy have not been explored.

PATIENT CONCERNS

A 44-year-old Chinese women presented with cough and dyspnea with a history of advanced lung adenocarcinoma.

DIAGNOSIS

A PET/CT scan revealed primary tumors in bilateral lung lobes and multiple metastases in lymph nodes and bones. And ultrasound-guided left cervical lymph node biopsy revealed the pathological diagnosis was poor differentiated lung adenocarcinoma.

INTERVENTIONS

The patients was started to be treated with 4 cycles of pemetrexed, carboplatin and bevacizumab, followed by one cycle of docetaxel, cisplatin and bevacizumab. As the ROS1-fusion was found by next generation sequencing, the patient received crizotinib treatment about 3 months.

OUTCOMES

After 5 cycles of chemotherapy, CT scans revealed increased size of bilateral lobe nodules indicative of progressive disease (PD). Then the patient received treatment of crizotinib and his progression-free survival reached 3 months. Due to uncontrollable disease progression, the patient expired.

LESSONS

The genetic profile of NSCLC patients might be altered in various therapeutic processes. Thus, repeated genetic testing might be important at each progression. Moreover, immunotherapy might be a powerful weapon to overcome the resistance to Tyrosine kinase inhibitors (TKIs) in future.

[Disparities of EGFR mutations between Biopsy and Rebiopsy in Non-small Cell Lung Cancer Patients]

背景与目的

表皮生长因子受体(epidermal growth factor receptor, EGFR)靶向治疗能够显著提高EGFR突变的晚期肺腺癌患者预后生存，但治疗及异质性等因素可导致初次和疾病进展时EGFR基因状态发生改变。为了探讨真实世界中EGFR基因突变在疾病进展和基线时的差异，我们开展了此项研究。

方法

收集2015年1月-2017年12月在吉林省肿瘤医院进行EGFR基因检测的61例配对标本数据并进行分析。标本取材时间为治疗前和疾病进展时，所有标本均经病理学或细胞学证实，标本来源为肿瘤组织﹑恶性胸腔积液和血浆，患者为初治，一线接受化疗或靶向治疗，采用扩增阻滞突变系统法(Amplification Refractory Mutation System, ARMS)对29种EGFR基因突变进行检测。

结果

初次和再次活检相比(n=61)，肿瘤组织、恶性胸腔积液和血浆标本所占的比例分别为90.2% vs 88.5%、6.6% vs 6.6%和3.2% vs 4.9%，其中标本类型前后一致的患者(n=50)EGFR突变差异率为72.0%，标本类型不一致患者(n=11)为36.3%；治疗前EGFR突变率为95.1%，治疗后为91.8%，二者的差异率为63.9%；化疗患者(n=13)治疗前EGFR突变率为69.2%，治疗后为92.3%，二者差异率为46.1%；靶向治疗患者(n=48)治疗前EGFR突变率为100%，治疗后为91.7%，二者差异率为70.8%。EGFR基因变化类型有4类：野生型变为突变型(4.9%)、突变消失(8.2%)、敏感突变类型互变(1.6%)和突变种类增加(49.1%)。

结论

临床实践中，晚期非小细胞肺癌(non-small cell lung cancer, NSCLC)患者由于标本取材部位和类型及治疗的影响，治疗前后EGFR基因突变具有较大差异性，动态检测并明确EGFR基因状态，可以为临床医生选择精准的后续靶向治疗方案提供参考。

Therapeutic bronchoscopy in the era of genotype directed lung cancer management

Lung cancer is the leading cause of cancer related deaths. Non-small cell lung cancer (NSCLC) accounts for ~85% of lung cancers. Our understanding of driver mutations and genotype directed therapy has revolutionized the management of advanced NSCLC. Commonly described mutations include mutations in epidermal growth factor (EGFR) & BRAF and translocations in anaplastic lymphoma kinase (ALK) & rat osteosarcoma (ROS1). Drugs directed against these translocations have significantly improved progression free survival individually and have shown a survival benefit when studied in the Lung Cancer Mutation Consortium (median survival 3.5 vs. 2.4 years compared to standard therapy). In a related yet parallel universe, the number of bronchoscopic ablative modalities available for management of cancer related airway obstruction have increased exponentially over the past decade. A wealth of literature has given us a better understanding of the technical aspects, benefits and risks associated with these procedures. While they all show benefits in terms of relieving airway obstruction, symptom control, quality of life and lung function testing, their complication rates vary based on the modality. The overall complication rate was ~4% in the AQuIRE registry. Bronchoscopic therapeutic modalities include rigid bronchoscopy with mechanical debulking, laser, thermo-coagulation [electrocautery & argon plasma coagulation (APC)], cryotherapy, endobronchial brachytherapy (EBT), photodynamic therapy (PDT), intratumoral chemotherapy (ITC) and transbronchial needle injection (TBNI) of chemotherapy. Intuitively, one would assume that the science of driver mutations would crisscross with the science of bronchoscopic ablation as they overlap in the same patient population. Sadly, this is not the case and there is a paucity of literature looking at these fields together. This results in several unanswered questions about the interplay between these two therapies.

Transbronchoscopic patient biopsy-derived xenografts as a preclinical model to explore chemorefractory-associated pathways and biomarkers for small-cell lung cancer

Insufficient tumor tissue is a major barrier for cancer biology research in small-cell lung cancer (SCLC) and has driven the development of patient-derived xenografts (PDXs) from biopsy tumor tissues. Here, we utilized transbronchoscopic biopsy specimens from SCLC tumors to establish PDXs and evaluated the genomic profile using next-generation sequencing and an RNA sequencing platform. The PDX establishment rate was 54.1% (40/74). PDXs largely recapitulated the major characteristics of their corresponding primary tumors, such as histopathology, genetic profile, and chemo-responsiveness. Compared with chemosensitive (chemo-S) PDXs, chemorefractory (chemo-R) PDXs demonstrated significant gene aberrances in the mitogen-activated protein kinase (MAPK) pathway and a higher frequency of receptor tyrosine kinase (RTK)-related genes. Phosphorylated ERK (pERK) was associated with chemo-R status. Patients with positive pERK expression demonstrated significantly inferior progression-free survival after first-line chemotherapy compared with that of patients who were negative for pERK (p < 0.001). Collectively, transbronchoscopic biopsy SCLC PDXs can serve as a model for genomic profiling and identifying biomarkers predictive of chemo-R status. Using PDXs, RTK-related gene aberrances and pERK expression were found to be associated with chemo-R SCLC.

Expression of PD-1 and PD-L1 increase in consecutive biopsies in patients with classical Hodgkin lymphoma

High expression of programmed death receptor 1 (PD-1) and its ligand (PD-L1) by leukocytes in primary classical Hodgkin lymphoma (cHL) is associated with inferior outcome. However, it is unclear how expression varies during disease progression, and in the event of relapse. Our aim was to study PD-1 and PD-L1 in consecutive biopsies from untreated and treated cHL patients. We screened pathology registries from 3500 cHL patients. Eleven patients had a diagnostic cHL biopsy and a previous benign lymph node biopsy reclassified as cHL when reviewed and designated as the untreated. Thirty patients had a primary and a relapse biopsy, designated as the treated. Biopsies were immunostained to detect PD-1+ and PD-L1+ leukocytes, and PD-L1+ tumor cells. In the untreated, none of the markers were statistically significantly different when biopsies 1 and 2 were compared. In the treated, 19, 22, and 18 of 30 cases had increased proportions of PD-1+ leukocytes, PD-L1+ leukocytes and PD-L1+ tumor cells, respectively, and were all statistically significantly increased when primary and relapse biopsies were compared. PD-1 and PD-L1 most likely increase due to primary treatment with chemotherapy and radiotherapy, which could have implications regarding treatment with PD-1 inhibitors.

[Influence of Different Therapies on EGFR Mutants by Circulating Cell-free DNA of Lung Adenocarcinoma and Prognosis]

背景与目的

表皮生长因子受体（epidermal growth factor receptor, EGFR）基因突变与肺腺癌患者TKI靶向治疗疗效和预后密切相关，常规组织分析其突变状态有诸多局限。本研究旨在探讨非小细胞肺癌（non-small cell lung cancer, NSCLC）患者血液循环游离DNA（cell-free DNA, cfDNA）检测EGFR基因突变在治疗前、传统化疗以及靶向治疗后的表达差异。分析血液cfDNA是否能准确检测EGFR基因突变并监测耐药基因T790M的变化，以及TKI在靶向治疗患者中的预后价值。

方法

应用ARMS（amplification refractory mutation system）法检测107例（50例治疗前、29例传统化疗和28例靶向治疗）肺癌患者配对血液和肿瘤组织样本的EGFR基因突变并比较其表达差异；计算检测的一致性、敏感性和特异性；分析血检对靶向治疗患者的预后价值。

结果

血浆cfDNA检测EGFR总突变率在107例肺癌患者中为56%（60例），而配对肿瘤组织样本检出率为77.6%（83例）。一一配对比较发现两者总体一致率为68.2%。血检的敏感性是72.3%，特异性为100%。依据治疗状态分组后发现治疗前组患者血液和肿瘤组织样本的检测一致率最高（74%, 37/50），而靶向组一致率最低（57.1%, 16/28），提示靶向治疗改变血浆cfDNA中EGFR基因状态。具体分析靶向组不一致病例发现50%新检出含T790M的双突变，提示靶向治疗后耐药基因出现。生存分析证实血检含T790M双突变组的无进展生存期（progression-free survival, PFS）和总生存期（overall survival, OS）均显著低于无T790M突变组。

结论

应用ARMS法检测血液循环游离DNA（circulating cell-free DNA, cfDNA）的EGFR基因突变是一种特异性高、敏感性好的检测方法。适用于治疗前晚期肺癌患者的EGFR基因突变状态检测。同时，适用于靶向治疗后监测T790M耐药突变状态及预测患者预后。

Cumulative smoking dose affects the clinical outcomes of EGFR-mutated lung adenocarcinoma patients treated with EGFR-TKIs: a retrospective study

Background

Although lung adenocarcinoma with activating epidermal growth factor receptor (EGFR) mutations is common in never smokers, one-third of the patients are ever-smokers. We aimed to investigate the effect of cumulative smoking dose(CSD) on clinical outcomes, including progression-free survival (PFS) and overall survival (OS), in patients with EGFR-mutated lung adenocarcinoma receiving EGFR-tyrosine kinase inhibitors (TKIs).

Methods

We retrospectively analyzed 142 patients with EGFR-mutation positive advanced or recurrent lung adenocarcinoma who were administered gefitinib, erlotinib, afatinib, and osimertinib. These patients were classified based on their CSD as never smokers, light smokers (≤10 pack-years [PYs]), moderate smokers (11–30 PYs), and heavy smokers (> 30 PYs). PFS and OS were analyzed according to smoking subgroups via Kaplan-Meier curves.

Results

Among the 142 patients, 91 (64.1%), 12 (8.5%), 22 (15.5%), and 17 (12%) were never, light, moderate, and heavy smokers, respectively. CSD was inversely associated with median PFS in a statistically significant dose-dependent manner (11.8 months (mo), 11.0 mo, 7.4 mo, and 3.9 mo; p < 0.001). Statistically significant negative association was observed between CSD and median OS (33.6 mo, 26.3 mo, 20 mo, and 8.9 mo; p < 0.001). In the multivariate analysis adjusted for age, sex, performance status, stage, and timing of EGFR-TKIs, CSD was an independent predictive factor for disease progression (hazard ratio [HR], 4.00; 95% confidence interval [CI], 1.95–8.23; p = 0.012) and OS (HR, 3.9; 95% CI, 1.84–8.28; p < 0.001).

Conclusion

CSD is an important predictive and prognostic factor in patients with EGFR-mutated lung adenocarcinoma, and associated smoking-related gene signatures might affect the outcomes.

Electronic supplementary material

The online version of this article (10.1186/s12885-018-4691-0) contains supplementary material, which is available to authorized users.

Efficacy of combined icotinib and pemetrexed in EGFR mutant lung adenocarcinoma cell line xenografts

Background

The combination of EGFR tyrosine kinase inhibitors (TKIs) and chemotherapy is thought to increase treatment efficacy in non‐small‐cell lung cancer (NSCLC). This study investigated the efficacy and potential mechanisms of different combined modes of icotinib plus pemetrexed in EGFR‐mutant lung adenocarcinoma cell line xenograft models.

Methods

Nude mice were subcutaneously injected with EGFR‐mutant human lung adenocarcinoma cells (HCC827) and randomized into six treatment groups. Tumor xenograft volumes were monitored and recorded. Microvessel density (MVD) and proliferation and apoptosis rates were evaluated with CD34 positive cell counting, and Ki‐67 and caspase‐3 scores, respectively, and determined via immunohistochemistry. Thymidylate synthase (TS), EGFR, and downstream signaling molecule expression was detected by Western blotting.

Results

The volume and weight of tumor xenografts in the sequential pemetrexed followed by icotinib (Pem‐Ico) group and the concurrent icotinib and pemetrexed (Ico + Pem) group were significantly smaller than those in the control, pemetrexed (Pem), icotinib (Ico), and sequential icotinib followed by pemetrexed (Ico‐Pem) groups. Compared to other groups, a decrease in the MVD and proliferation rate and an increase in the apoptosis rate were observed in the Pem‐Ico and Ico + Pem groups. TS expression and EGFR, AKT, and MAPK phosphorylation were significantly reduced in the Pem‐Ico or Ico + Pem groups.

Conclusions

Pem‐Ico had additive antitumor activity in vivo, similar to Ico + Pem, both of which are suggested as potentially optimized strategies for treating EGFR‐mutant lung adenocarcinoma.

Circulating tumor DNA (ctDNA) in the era of personalized cancer therapy

The heterogeneity of tumor is considered as a major difficulty to victorious personalized cancer medicine. There is an extremeneed of consistent response evaluation for in vivo tumor heterogeneity anditscoupledconflict mechanisms. In this occasion researchers will be able to keep pace withpredictive, preventive, personalized, and Participatory (P4) medicine for cancer managements. In fact tumor heterogeneity is a central part of cancer evolution,soin order to progress in understanding of the dynamics within a tumor some diagnostic apparatus should be improved. Latest molecular techniques like Next generation Sequencing (NGS) and ultra-deep sequencing could disclose some clones within a liquid tumor biopsy which mainly responsible of treatment resistance. Circulating tumor DNA (ctDNA) as a main component of liquid biopsy is agifted biomarker for cancer mutation tracking as well as profiling. Personalized medicine facilitate learning regarding to genetic pools of tumor and their possible respond to treatment which could be much easier by using of ctDNA.With this information, cliniciansarelooking forward to find the best strategies for prevention, screening, and treatment in the way of precision medicine. Currently, numerous clinical efficacy of such informative improved treatment are in hand. Here we represent the review of plasma-derived ctDNA studies use in personalized cancer managements.

Mutation abundance affects the therapeutic efficacy of EGFR-TKI in patients with advanced lung adenocarcinoma: A retrospective analysis

PURPOSE

To investigate the influence of mutation abundance and sites of epidermal growth factor receptor (EGFR) on therapeutic efficacies of EGFR-tyrosine kinase inhibitor (EGFR-TKIs) treatments of patients with advanced non-small cell lung carcinoma (NSCLC).

METHODS

EGFR mutational sites and mutation abundance were analyzed by amplification refractory mutation system (ARMS) in paraffin-embedded tissue sections taken from primary or metastatic tumors of 194 NSCLC patients.

RESULTS

The median progression-free survival (PFS) time of the enrolled patients was 9.3 months (95% CI, 8.2-10.8 months). The PFS was significantly different with EGFR gene mutation abundance after EGFR-TKI therapy (P = 0.014). The median PFS was significantly longer when the cut-off value of EGFR mutation abundance of exon 19 or exon 21, and solely exon 19 was > 26.7% and 61.8%, respectively. For patients who received EGFR-TKI as first-line treatment, the median PFS was significantly longer in the high mutation abundance group than in the low mutation abundance group (12.7 vs 8.7 months, P = 0.002).

CONCLUSION

The PFS benefits were greater in patients with a higher abundance of exon 19 deletion mutations in the EGFR gene after EGFR-TKI treatment and first line EGFR-TKI treatment led to improved PFS in high mutation abundance patients.

Clinically significant sub-clonality for common drivers can be detected in 26% of KRAS/EGFR mutated lung adenocarcinomas

Genetic sub-clonality has been described in multiple malignancies, however the presence of sub-clonality for major drivers in lung adenocarcinoma and its clinical significance is a subject under debate. Using molecular and morphometric approach, 347 lung adenocarcinoma samples were analyzed for KRAS and EGFR sub-clonality, which was further correlated with clinical and pathological variables.KRAS and EGFR mutations were identified in 100 (29%) and 82 (23%) cases, respectively. One hundred and forty four KRAS or EGFR positive cases were also available for morphometric analysis, among which 37 (26%) were defined as sub-clonal. The presence of sub-clonality was associated with shorter survival time (p=0.02). Interestingly, cases with sub-clonality were also associated with earlier disease stage (89% vs 66% stage I disease in sub-clonal vs clonal cases, respectively, p=0.01) and less lymph node involvement (8% vs 25% in sub-clonal vs clonal cases, respectively, p=0.02). Our findings demonstrate the presence of sub-clonality for mutations in common drivers in lung adenocarcinoma and link it both to earlier disease stage and to poor survival. These findings are in line with the different evolutionary models that can present with genetic sub-clonality.

The emerging treatment landscape of advanced non-small cell lung cancer

Lung cancer remains the leading cause of cancer related death worldwide. Despite broad advances in diagnostics and therapy, the five-year overall survival for patients with advanced non-small cell lung cancer (NSCLC) has not significantly changed over the past few years. Following the decoding of human cancer genome and the advent of therapies targeting driver mutations, the selection of systemic therapy changed from "one size fits all" approach to a more precise selection of biologic therapies targeting distinct genetic profiles. Molecular alterations can be targeted by specific drugs that are administered orally, have higher response rates and a better toxicity profile compared to standard chemotherapy. More recently, better understanding of the interactions between tumor cells and the immune system has led to the development of new therapeutic strategies that enhance the body's own immune response towards antitumor immunity. Robust data on these new drugs have been generated not only in the second-line setting, but also as first line therapy and in combination with standard therapies. In this review, we aim to illustrate a comprehensive up-to-date within the newest advances in the field of NSCLC, with the view to educate new practitioners and stimulate new thoughts for clinical trials.

Multiple single cell screening and DNA MDA amplification chip for oncogenic mutation profiling

The oncogenic mutation heterogeneity of the cancer cell population has been proven to be essential for predicting both drug-response and drug-resistance of targeted therapies, such as tyrosine kinase inhibitors. It is necessary to accurately evaluate the mutation heterogeneity, oncogenic mutation and resistant mutation profiling at a single cell level. However, there are two major hurdles in the process. First, majority of the cells in tumor tissue are non-cancer cells, which cause background noise. Second, the work load and cost of next generation sequencing on dozens of single cells are prohibitive. To address both these issues, we developed a microfluidic chip for profiling of dozens of selected cells. With the help of a novel tri-states valve structure, which performs precise controlling of the cell/reagent movement, as well as active mixing of different reagents, trapping/identification/lysis and in situ MDA amplification was achieved at a single cell level on the same chip. Using a proof-of-concept assay mimicking EGFR targeting drug Gefitinib treatment of lung cancer cells, the new method was validated as capable of not only detecting the existence of multiple mutations, but also providing complete information of the mutation scenario at the single cell level by using cost-effective Sanger's sequencing.

Quantitative image variables reflect the intratumoral pathologic heterogeneity of lung adenocarcinoma

We aimed to compare quantitative radiomic parameters from dual-energy computed tomography (DECT) of lung adenocarcinoma and pathologic complexity.

A total 89 tumors with clinical stage I/II lung adenocarcinoma were prospectively included. Fifty one radiomic features were assessed both from iodine images and non-contrast images of DECT datasets. Comprehensive histologic subtyping was evaluated with all surgically resected tumors. The degree of pathologic heterogeneity was assessed using pathologic index and the number of mixture histologic subtypes in a tumor. Radiomic parameters were correlated with pathologic index. Tumors were classified as three groups according to the number of mixture histologic subtypes and radiomic parameters were compared between the three groups.

Tumor density and 50^th through 97.5^th percentile Hounsfield units (HU) of histogram on non-contrast images showed strong correlation with the pathologic heterogeneity. Radiomic parameters including 75^th and 97.5^th percentile HU of histogram, entropy, and inertia on 1-, 2- and 3 voxel distance on non-contrast images showed incremental changes while homogeneity showed detrimental change according to the number of mixture histologic subtypes (all Ps < 0.05).

Radiomic variables from DECT of lung adenocarcinoma reflect pathologic intratumoral heterogeneity, which may help in the prediction of intratumoral heterogeneity of the whole tumor.

Heterogeneity-based, multiple mechanisms in the resistance to osimertinib (AZD9291): A case report

Osimertinib is a novel, irreversible, mutant‐selective epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor targeting EGFR mutations and the EGFR T790 mutation. Here, we report a woman with EGFR‐mutated lung adenocarcinoma who, after 23‐month treatment with gefitinib, developed the EGFR T790M mutation, which converted the T790M status from positive to negative before osimertinib treatment and developed MET amplification, leading to rapid progression on osimertinib in two months. Subsequent treatment with crizotinib and c‐Met inhibitor plus gefitinib also failed to improve the clinical outcome, suggesting the potential existence of another resistance mechanism. Our findings revealed the underlying multiple and heterogeneous mechanisms in resistance to osimertinib, suggesting combination strategies should be considered post‐osimertinib progression.

Clinical value of ALU concentration and integrity index for the early diagnosis of ovarian cancer: A retrospective cohort trial

CA125 amounts have a large overlap in ovarian cancer and benign diseases. We conducted a retrospective cohort trial to assess the clinical value of circulating cell-free DNA concentration and integrity index for the diagnosis of ovarian cancer. A total of 150 patients were recruited. Plasma samples of 24 ovarian cancer patients, 12 benign ovarian cysts, and 12 healthy controls were assessed. By amplifying short ALU-115 repeat and long ALU-219 fragments, circulating cell-free DNA concentrations and integrity index were measured. Plasma ALU-219 fragment levels and integrity index were significantly higher in the ovarian cancer group compared with the benign disease and healthy control groups (p = 0.023 and p = 0.004, respectively). These findings indicated that plasma ALU-219 levels and integrity may have a clinical value in the early diagnosis of ovarian cancer.

Identification of EGFR mutations in cytological specimens of non-small cell lung carcinoma from a single institute

Epidermal growth factor receptor (EGFR) mutation testing is pivotal for the precise treatment of non-small cell lung carcinoma (NSCLC). Generally, detection of EGFR mutations in surgical specimens is the most accurate and the most reliable. However, some NSCLC patients in advanced stages are inoperable. Therefore, other specimens such as cytological samples are alternative options for EGFR mutation detection. In this study, cytological samples from 291 NSCLC patients were tested for EGFR mutations using the amplification-refractory mutation system (ARMS). The results showed that the EGFR mutation rate was 45.3%, and the most common mutation type was deletion in exon 19 (19del), followed by L858R mutation in exon 21. The results were consistent with that of the large cohort histological samples. This study demonstrates that using cell block for EGFR mutation detection has a high success rate and can yield reliable results. It also solidifies that the use of cytological samples possesses relatively high clinical practicability, so that cytological samples may substitute histological samples. In addition, an assessment of the tumor cell quantity prior to detection could improve the positive rate. Considering tumor heterogeneity, both histological and cytological samples are suggested to be collected for testing, if possible.

Retreatment with icotinib in a patient with metastatic lung adenocarcinoma

A patient with advanced non-small cell lung cancer (NSCLC) was successfully treated with icotinib. The tumor relapsed after a partial response and the patient was retreated with icotinib after temporary cessation. Surprisingly we found that the tumor responded to icotinib again. The exact mechanism of this phenomenon is still unclear. A better understanding of the biological basis of involved events will help us to improve treatment of advanced NSCLC.

Quantification of mutant alleles in circulating tumor DNA can predict survival in lung cancer

Purpose

We aimed to investigate the feasibility of droplet digital PCR (ddPCR) for the quantitative and dynamic detection of EGFR mutations and next generation sequencing (NGS) for screening EGFR-tyrosine kinase inhibitors (EGFR-TKIs) resistance-relevant mutations in circulating tumor DNA (ctDNA) from advanced lung adenocarcinoma (ADC) patients.

Results

Detection limit of EGFR mutation in ctDNA by ddPCR was 0.04%. Taking the EGFR mutation in tumor tissue as the golden standard, the concordance of EGFR mutations detected in ctDNA was 74% (54/73). Patients with EGFR mutation in ctDNA (n = 54) superior progression-free survival (PFS, median, 12.6 vs. 6.7 months, P < 0.001) and overall survival (OS, median, 35.6 vs. 23.8 months, P = 0.028) compared to those with EGFR wild type in ctDNA (n = 19). Patients with high EGFR-mutated abundance in ctDNA (> 5.15%) showed better PFS compared to those with low EGFR mutated abundance (≤ 5.15%) (PFS, median, 15.4 vs. 11.1 months, P = 0.021). NGS results showed that 66.6% (8/12) total mutational copy number were elevated and 76.5% (26/34) mutual mutation frequency increased after disease progression.

Methods

Seventy-three advanced ADC patients with tumor tissues carrying EGFR mutations and their matched pre- and post-EGFR-TKIs plasma samples were enrolled in this study. Absolute quantities of plasma EGFR mutant and wild-type alleles were measured by ddPCR. Multi-genes testing was performed using NGS in 12 patients.

Conclusions

Dynamic and quantitative analysis of EGFR mutation in ctDNA could guide personalized therapy for advanced ADC. NGS shows good performance in multiple genes testing especially novel and uncommon genes.

Circulating cell-free DNA has a high degree of specificity to detect exon 19 deletions and the single-point substitution mutation L858R in non-small cell lung cancer

Detection of an epidermal growth factor receptor (EGFR) mutation in circulating cell-free DNA (cfDNA) is a noninvasive method to collect genetic information to guide treatment of lung cancer with tyrosine-kinase inhibitors (TKIs). However, the association between cfDNA and detection of EGFR mutations in tumor tissue remains unclear. Here, a meta-analysis was performed to determine whether cfDNA could serve as a substitute for tissue specimens for the detection of EGFR mutations. The pooled sensitivity, specificity, and areas under the curve of cfDNA were 0.60, 0.94, and 0.9208 for the detection of EGFR mutations, 0.64, 0.99, and 0.9583 for detection of the exon 19 deletion, and 0.57, 0.99, and 0.9605 for the detection of the L858R mutation, respectively. Our results showed that cfDNA has a high degree of specificity to detect exon 19 deletions and L858R mutation. Due to its high specificity and noninvasive characteristics, cfDNA analysis presents a promising method to screen for mutations in NSCLC and predict patient response to EGFR-TKI treatment, dynamically assess treatment outcome, and facilitate early detection of resistance mutations.

Mixed Responses to Systemic Therapy Revealed Potential Genetic Heterogeneity and Poor Survival in Patients with Non-Small Cell Lung Cancer

BACKGROUND

A subset of patients with non-small cell lung cancer (NSCLC) fosters mixed responses (MRs) to epidermal growth factor receptor (EGFR)-tyrosine kinase inhibitors (TKIs) or chemotherapy. However, little is known about the clinical and molecular features or the prognostic significance and potential mechanisms.

METHODS

The records of 246 consecutive patients with NSCLC receiving single-line chemotherapy or TKI treatment and who were assessed by baseline and interim positron emission tomography/computed tomography scans were collected retrospectively. The clinicopathological correlations of the MR were analyzed, and a multivariate analysis was performed to explore the prognostic significance of MR.

RESULTS

The overall incidence of MR to systemic therapy was 21.5% (53/246) and predominated in patients with stage IIIB-IV, EGFR mutations and those who received TKI therapy (p < .05). Subgroup analyses based on MR classification (efficacious versus inefficacious) showed significant differences in subsequent treatment between the two groups (p < .001) and preferable progression-free survival (PFS) and overall survival (OS) in the efficacious MR group. Multivariate analyses demonstrated that the presence of MR was an independent unfavorable prognostic factor for PFS (hazard ratio [HR], 1.474; 95% confidence interval [CI], 1.018-2.134; p = .040) and OS (HR, 1.849; 95% CI, 1.190-2.871; p = .006) in patients with NSCLC. Induced by former systemic therapy, there were more T790M (18%), concomitant EGFR mutations (15%), and changes to EGFR wild type (19%) in the MR group among patients with EGFR mutations, which indicated higher incidence of genetic heterogeneity.

CONCLUSION

MR was not a rare event in patients with NSCLC and tended to occur in those with advanced lung adenocarcinoma treated with a TKI. MR may result from genetic heterogeneity and is an unfavorable prognostic factor for survival. Further studies are imperative to explore subsequent treatment strategies. The Oncologist 2017;22:61-69Implications for Practice: Tumor heterogeneity tends to produce mixed responses (MR) to systemic therapy, including TKI and chemotherapy; however, the clinical significance and potential mechanisms are not fully understood, and the subsequent treatment after MR is also a clinical concern. The present study systemically assessed patients by PET/CT and differentiated MR and therapies. The study identified a relatively high incidence of MR in patients with advanced NSCLC, particularly those treated with targeted therapies. An MR may be an unfavorable prognostic factor and originate from genetic heterogeneity. Further studies are imperative to explore subsequent treatment strategies.