Outcomes of research biopsies in clinical trials of EGFR mutation-positive non-small cell lung cancer patients pretreated with EGFR-tyrosine kinase inhibitors

Safety of image guided research biopsies in patients with thoracic malignancies

OBJECTIVE

A common opportunity to collect research samples is during image-guided percutaneous core needle biopsies (CNBs) performed when clinically indicated or for assessing clinical trial eligibility. The relative safety of extra CNBs collected for research is undefined.

MATERIALS AND METHODS

Patients who underwent CNB for research purposes only [RO], as clinically indicated [CI], or as part of a clinical trial [CT] were identified. 30-day post-procedure adverse events (AEs) among the cohorts were examined and compared to the 2020 Society of Interventional Radiology QI guidelines.

RESULTS

236 patients with thoracic cancers (90 % NSCLC, 5 % SCLC, 4 % mesothelioma, and 1 % thymic) had 292 CNBs (63 RO, 229 CI + CT). AEs occurred in 13 % of both the RO and CI + CT groups. Compared to the CI + CT group, the RO group did not have a higher pneumothorax incidence (RO: 5/29 [17 %], CI + CT: 18/114 [16 %], p = 0.79); both were below the suggested QI threshold of 45 % for pneumothorax. There was a negative association between number of cores obtained and risk of AE (AE vs no AE mean cores = 3.5 vs 4.8). After adjusting for the number of cores and smoking history, RO vs CI + CT lung biopsies had a higher risk of AEs (adjusted relative risk [aRR] = 2.44, 1.08-5.55, p = 0.03 vs non-lung aRR = 0.86, 0.10-7.09, p = 0.89).

CONCLUSION

CNBs performed for research purposes do not have a significantly increased risk of AEs when compared to those performed for clinical trials and/or when clinically indicated. However, AEs were most frequent in lung biopsies. When performing research biopsies, a target other than lung may be preferred when clinically appropriate.

Cone-Beam Computed Tomography-Derived Augmented Fluoroscopy Improves the Diagnostic Yield of Endobronchial Ultrasound-Guided Transbronchial Biopsy for Peripheral Pulmonary Lesions

Background: Endobronchial ultrasound-guided transbronchial biopsy (EBUS-TBB) is used for the diagnosis of peripheral pulmonary lesions (PPLs), but the diagnostic yield is not adequate. Cone-beam computed tomography-derived augmented fluoroscopy (CBCT-AF) can be utilized to assess the location of PPLs and biopsy devices, and has the potential to improve the diagnostic accuracy of bronchoscopic techniques. The purpose of this study was to verify the contribution of CBCT-AF to EBUS-TBB. Methods: Patients who underwent EBUS-TBB for diagnosis of PPLs were enrolled. The navigation success rate and diagnostic yield were used to evaluate the effectiveness of CBCT-AF in EBUS-TBB. Results: In this study, 236 patients who underwent EBUS-TBB for PPL diagnosis were enrolled. One hundred fifteen patients were in CBCT-AF group and 121 were in non-AF group. The navigation success rate was significantly higher in the CBCT-AF group (96.5% vs. 86.8%, p = 0.006). The diagnostic yield was even better in the CBCT-AF group when the target lesion was small in size (68.8% vs. 0%, p = 0.026 for lesions ≤10 mm and 77.5% vs. 46.4%, p = 0.016 for lesions 10–20 mm, respectively). The diagnostic yield of the two study groups became similar when the procedures with a failure of navigation were excluded. The procedure-related complication rate was similar between the two study groups. Conclusion: CBCT-AF is safe, and effectively enhances the navigation success rate, thereby increasing the diagnostic yield of EBUS-TBB for PPLs.

Post-Progression Survival in Secondary EGFR T790M-Mutated Non-Small-Cell Lung Cancer Patients With and Without Osimertinib After Failure of a Previous EGFR TKI

BACKGROUND

Osimertinib is effective in non-small-cell lung cancer (NSCLC) with an acquired epidermal growth factor receptor (EGFR) T790M mutation, the most common resistance mechanism to first- and second-generation EGFR tyrosine kinase inhibitors (TKIs).

OBJECTIVES

We aimed to evaluate survival outcome of patients with EGFR-mutant NSCLC who have progressed on previous EGFR TKI therapy.

PATIENTS AND METHODS

Advanced NSCLC patients with EGFR mutation after acquired resistance to first- or second-generation EGFR TKI who received tumor rebiopsy after EGFR TKI failure from 1 January 2012 to 31 December 2017 were reviewed. Patient clinical characteristics, T790M mutation status, and post-progression survival (PPS) were recorded by chart review.

RESULTS

We included 240 patients and the percentage of secondary T790M mutations in first time tissue rebiopsy was 52.9%. 38 of the initial T790M-negative patients received second rebiopsies and 14 (36.8%) of these were T790M positive. The duration between first and second rebiopsy tended to be longer in patients who had T790M mutation in the second biopsy (11.5 vs. 6.9 months, p = 0.043). After EGFR TKI failure, the median PPS of patients who had the T790M mutation and history of osimertinib use was 42.6 months (95% CI 34.6-50.5), compared to 18.0 (95% CI 9.6-26.4) months in T790M-positive patients without a history of osimertinib use, and 18.8 (95% CI 9.3-28.4) months in patients with no T790M mutation (p < 0.0001). Multivariate analysis showed that history of osimertinib use was correlated with improved survival.

CONCLUSIONS

These data further emphasize that osimertinib should be a standard of care in patients with pretreated EGFR T790M-positive NSCLC.

Second-line treatment of EGFR T790M-negative non-small cell lung cancer patients

Epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs) are the currently recommended treatment for advanced EGFR mutation-positive non-small cell lung cancer (NSCLC). Acquired resistance inevitably develops, with the EGFR T790M mutation comprising approximately 55% of the mechanisms of resistance following first- or second-generation EGFR-TKI therapy (e.g. gefitinib, erlotinib, afatinib, and dacomitinib). Patients without T790M are a heterogeneous group for whom platinum-based chemotherapy is currently recommended as a second-line treatment. In addition to secondary mutations in EGFR (e.g. T790M), the currently known resistance mechanisms can be classified into the following three categories: bypass pathways, downstream signaling pathways, and histologic transformations. Given the evolving knowledge and convenience of diagnosing acquired resistance mechanisms by next-generation sequencing and liquid biopsy, exploratory studies targeting these resistance mechanisms and incorporating immunotherapy into the treatment paradigm have become the mainstream of future development. This review focuses on acquired resistance mechanisms other than T790M that develop after first- or second-generation EGFR-TKI therapy. Exploratory second-line treatments targeting resistance mechanisms as well as combination immunotherapy and chemotherapy in ongoing clinical trials are reviewed here. We also highlight the recent development of next-generation sequencing and liquid biopsy in this field.

The Factors Predicting Concordant Epidermal Growth Factor Receptor (EGFR) Mutation Detected in Liquid/Tissue Biopsy and the Related Clinical Outcomes in Patients of Advanced Lung Adenocarcinoma with EGFR Mutations

Liquid biopsy to identify epidermal growth factor receptor (EGFR) gene mutations from circulating tumor DNA (ctDNA) for lung adenocarcinoma is less invasive than traditional tissue biopsy. Most patients have concordant results in liquid/tissue biopsy, while the clinical significance of concordant results remains unclear. Our study aimed to evaluate the predicting factors and clinical outcomes associated with concordant results in liquid/tissue biopsy in newly diagnosed lung adenocarcinoma patients with EGFR mutations. In the 80 patients of stage III or IV lung adenocarcinoma, 51 patients had EGFR mutations detected in tissue samples, while 33 (65%) of them had concordant results shown in liquid biopsy. Multivariable regression analysis showed that lymph node involvement (adjusted odds ratio (95% CI): 8.71 (1.88–40.35), p = 0.0057) and bone metastasis (adjusted odds ratio (95% CI): 9.65 (1.72–54.05), p = 0.0099) were the independent predicting factors for concordant results. Forty of these 51 patients were stage IV and were treated with EGFR tyrosine kinase inhibitors (TKIs). The concordant results in liquid/tissue samples were associated with significantly poorer progression-free survival (PFS) in univariate analysis. However, multivariable analysis showed that lymph node involvement was the only independent predicting factor for poorer PFS, while concordant results in liquid/tissue samples were excluded during variable selection. The concordant results in liquid/tissue samples might indicate a larger tumor burden, which actually contributes to poorer PFS.

Increasing Numbers and Reported Adverse Events in Patients with Lung Cancer Undergoing Inpatient Lung Biopsies: A Population-Based Analysis

INTRODUCTION

The use of molecular biomarkers to guide lung cancer management has led to increasing frequency and amounts of tissue required for repeat lung biopsies. While patient safety and reporting of adverse events has been increasingly emphasized in recent decades, the safety of lung biopsies in patients with lung cancer has only been studied in small cohorts. We therefore analyzed adverse events in patients with lung cancer undergoing lung biopsies in the National Hospital Discharge Survey (NHDS) database.

METHODS

Data were abstracted using ICD-9 lung cancer diagnosis (162.X) and lung biopsy procedure codes (33.20, 33.24, 33.25, 33.26, 33.27, 33.28) from 2001 to 2010. Agency for Healthcare Research and Quality (AHRQ) Patient-Safety Indicators (PSI) were used to identify hospital-acquired adverse events. Weighted analyses were performed using SAS version 9.4.

RESULTS

A total of 540,747 patients were included for analysis. The number of biopsies increased over time, from 51,221 in 2001, to 63,239 in 2010 (P < 0.001). Overall, 159,683 (30%) patients suffered ≥ 1-PSI event during their hospitalization. Incidence of PSI varied by biopsy type: bronchoscopic (26%), percutaneous (34%), surgical (39%). The proportion of patients with ≥ 1 PSI event increased from 24% in 2001 to 38% in 2010 (P < 0.001). Patients with ≥ 1 PSI had longer length of stay (mean, 11.6 vs 8.1 days; P < 0.001) and higher in-hospital mortality (adjusted odds ratio, 5.9, 95% CI 3.9-8.9; P < 0.001).

CONCLUSIONS

The frequency of lung biopsies performed and rate of documented adverse events in hospitalized lung cancer patients have increased. These findings have policy, funding, research, and practice implications.

Management of acquired resistance to EGFR TKI-targeted therapy in advanced non-small cell lung cancer

Recent advances in diagnosis and treatment are enabling a more targeted approach to treating lung cancers. Therapy targeting the specific oncogenic driver mutation could inhibit tumor progression and provide a favorable prognosis in clinical practice. Activating mutations of epidermal growth factor receptor (EGFR) in non-small cell lung cancer (NSCLC) are a favorable predictive factor for EGFR tyrosine kinase inhibitors (TKIs) treatment. For lung cancer patients with EGFR-exon 19 deletions or an exon 21 Leu858Arg mutation, the standard first-line treatment is first-generation (gefitinib, erlotinib), or second-generation (afatinib) TKIs. EGFR TKIs improve response rates, time to progression, and overall survival. Unfortunately, patients with EGFR mutant lung cancer develop disease progression after a median of 10 to 14 months on EGFR TKI. Different mechanisms of acquired resistance to first-generation and second-generation EGFR TKIs have been reported. Optimal treatment for the various mechanisms of acquired resistance is not yet clearly defined, except for the T790M mutation. Repeated tissue biopsy is important to explore resistance mechanisms, but it has limitations and risks. Liquid biopsy is a valid alternative to tissue re-biopsy. Osimertinib has been approved for patients with T790M-positive NSCLC with acquired resistance to EGFR TKI. For other TKI-resistant mechanisms, combination therapy may be considered. In addition, the use of immunotherapy in lung cancer treatment has evolved rapidly. Understanding and clarifying the biology of the resistance mechanisms of EGFR-mutant NSCLC could guide future drug development, leading to more precise therapy and advances in treatment.

Optimal management of EGFR-mutant non-small cell lung cancer with disease progression on first-line tyrosine kinase inhibitor therapy

The first-generation epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs), gefitinib and erlotinib, and the second-generation EGFR-TKI, afatinib, have all been approved as standard first-line treatments for advanced EGFR-mutant non-small cell lung cancer (NSCLC) based on superior progression-free survival results compared to platinum doublet chemotherapy regimens. Acquired resistance to an EGFR-TKI inevitably develops after a period of effective drug treatment. After tumor progression, many combination therapy regimens that include an EGFR-TKI, or EGFR-TKI monotherapy, have been tested in prospective trials with the aim of extending survival. Third-generation EGFR-TKIs such as osimertinib have been developed with the aim of overcoming the effects of EGFR T790M resistance mutation, which occurs in half of the patients with disease progression on EGFR-TKI therapy. Osimertinib has become the standard treatment in patients for whom tumor re-biopsy reveals an acquired EGFR T790M mutation following EGFR-TKI therapy. Other third-generation EGFR-TKIs, such as olmutinib, EGF816, and ASP8273, are still in the trial phase.