Detection of EGFR mutations in plasma circulating tumour DNA as a selection criterion for first-line gefitinib treatment in patients with advanced lung adenocarcinoma (BENEFIT): a phase 2, single-arm, multicentre clinical trial

Donor-derived cell-free DNA predicts allograft failure and mortality after lung transplantation

Background

Allograft failure is common in lung-transplant recipients and leads to poor outcomes including early death. No reliable clinical tools exist to identify patients at high risk for allograft failure. This study tested the use of donor-derived cell-free DNA (%ddcfDNA) as a sensitive marker of early graft injury to predict impending allograft failure.

Methods

This multicenter, prospective cohort study enrolled 106 subjects who underwent lung transplantation and monitored them after transplantation for the development of allograft failure (defined as severe chronic lung allograft dysfunction [CLAD], retransplantation, and/or death from respiratory failure). Plasma samples were collected serially in the first three months following transplantation and assayed for %ddcfDNA by shotgun sequencing. We computed the average levels of ddcfDNA over three months for each patient (avddDNA) and determined its relationship to allograft failure using Cox-regression analysis.

Findings

avddDNA was highly variable among subjects: median values were 3·6%, 1·6% and 0·7% for the upper, middle, and low tertiles, respectively (range 0·1%–9·9%). Compared to subjects in the low and middle tertiles, those with avddDNA in the upper tertile had a 6·6-fold higher risk of developing allograft failure (95% confidence interval 1·6–19·9, p = 0·007), lower peak FEV1 values, and more frequent %ddcfDNA elevations that were not clinically detectable.

Interpretation

Lung transplant patients with early unresolving allograft injury measured via %ddcfDNA are at risk of subsequent allograft injury, which is often clinically silent, and progresses to allograft failure.

Fund

National Institutes of Health.

Mutation tracking of a patient with EGFR-mutant lung cancer harboring de novo MET amplification: Successful treatment with gefitinib and crizotinib

OBJECTIVE

De novo mesenchymal-epithelial transition (MET) amplification is believed to promote primary resistance to epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors in the non-squamous non-small cell lung cancer (NSCLC). We sought to seek the treatment of a patient with EGFR-mutant NSCLC harboring de novo MET amplification.

MATERIALS AND METHODS

After clinical diagnosis, tissue and plasma samples were obtained from the patient and subjected to next-generation sequencing to identify and dynamic monitor the mutations.

RESULTS

The patient was treated with gefitinib monotherapy in the beginning and experienced primary resistance to gefitinib but achieved a good response to the combination therapy of gefitinib and crizotinib. He achieved a 16.8-month progress free survival with the combination therapy. NGS of plasma circulating cell-free tumor DNA shown that L858R mutation was no longer detectable and the copy number of MET dropped when the patient got remission.

CONCLUSIONS

The combination of EGFR- and MET- tyrosine kinase inhibitors may be an effective treatment for the rare mutations.

[Molecular Mechanism and Progression of Primary Resistance to EGFR-TKI - Analysis of 2 Cases]

酪氨酸激酶抑制剂(tyrosine-kinase inhibitor, TKI)类药物已经被证实对表皮生长因子受体(epidermal growth factor receptor, EGFR)敏感突变的晚期非小细胞肺癌(non-small cell lung cancer, NSCLC)患者有很好的疗效，优于化疗。但仍有部分敏感突变的患者出现原发性耐药。耐药的原因尚不明确，可能与EGFR基因的敏感突变与耐药突变共存、EGFR通路下游基因突变、MET扩增、BIM缺失多态性等因素相关。本文分享了2例原发性耐药病历并进行了原因分析。

EGFR plasma mutation in prediction models for resistance with EGFR TKI and survival of non-small cell lung cancer

Background

This study aims to clarify the prognostic role of epidermal growth factor receptor (EGFR) mutations in plasma of non-small cell lung cancer (NSCLC) for resistance to tyrosine kinase inhibitor (TKI), in correlation with clinical characteristics. A total of 94 Adenocarcinoma, clinical stage IV NSCLC patients with either E19del or L858R mutation were admitted to the prospective study from Jan-2016 to Jul-2018. EGFR mutations in plasma were detected by scorpions ARMS method. The Kaplan–Meier and Cox regression methods were used to estimate and test the difference of progression-free survival (PFS) and overall survival (OS) between groups. The prognostic power of each factor was appraised by the Bayesian Model Averaging (BMA) method.

Results

Among 94 patients, 28 cases still are good responses according to the RECIST criteria and negative for EGFR mutations in plasma. Of 66 resistant patients, EGFR mutations were positive in plasma of 57 cases (86.4%) which was higher than the value of pre-treatment (48.5%). Of which, 17 patients (25.8%) have the occurrence of EGFR mutations in plasma earlier than progression 2.1 (0.6–7.9) months. The secondary T790M mutation was found in the plasma of 32 cases (48.5%). Median PFS and OS for the study subjects were 12.9 (11.0–14.2) and 29.5 (25.2–41.3) months, respectively. The post-treatment EGFR plasma test with brain and new metastasis were detected as independent prognostic factors for worse PFS (P = 0.008, 0.016 and 0.028, respectively). While EGFR plasma (P = 0.044) with bone metastasis at baseline (P = 0.012), new metastasis (P = 0.003), and high cfDNA concentration (P = 0.004) serve as the worse survival factors, surgery treatment helps to prolong OS in NSCLC treated with EGFR TKI (P = 0.012). BMA analysis identified EGFR plasma test as the strongest prognostic factor for both PFS and OS (possibility of 100% and 99.7%, respectively).

Conclusions

EGFR plasma test is the powerfully prognostic factor for early resistance with EGFR TKI and worse survival in NSCLC regardless of clinical characteristics.