Clinical outcomes and secondary epidermal growth factor receptor (EGFR) T790M mutation among first-line gefitinib, erlotinib and afatinib-treated non-small cell lung cancer patients with activating EGFR mutations

Real-world analysis of survival outcomes in advanced EGFR-mutant NSCLC patients treated with platinum-pemetrexed after EGFR-TKI treatment failure

INTRODUCTION

EGFR tyrosine kinase inhibitors (TKIs) are the standard therapy for non-small-cell lung cancer (NSCLC) patients with EGFR-activating mutations in the first-line setting. Despite initial efficacy, resistance to EGFR-TKIs often develops, and platinum-based chemotherapy is the predominant subsequent treatment. For this study, we aimed to identify prognostic factors for overall survival (OS) and progression-free survival (PFS) among advanced EGFR-mutant NSCLC patients receiving platinum-pemetrexed after progression on EGFR-TKIs. Our analysis specifically focuses on 1st-line treatments limited to 1st- or 2nd-generation EGFR-TKIs, while not restricting later-line treatments involving osimertinib prior to chemotherapy.

MATERIALS AND METHODS

From 2012 to 2017, 363 patients who received first-line treatment with first- or second-generation EGFR-TKIs, including gefitinib, erlotinib, and afatinib were enrolled. Some patients received different EGFR-TKIs, including osimertinib, as later-line treatment before platinum-pemetrexed.

RESULTS

Median OS from the initiation of platinum-pemetrexed was 22.0 months and median PFS with platinum-pemetrexed was 6.2 months. In the multivariate Cox model, we identified three independent prognostic factors for better OS: postoperative recurrence (HR: 0.34, p = 0.004), first-line EGFR-TKI PFS ≥12 months (HR: 0.54, p = 0.002), and osimertinib treatment after platinum-pemetrexed (HR: 0.56, p = 0.005) while BMI <18.5 indicated poor prognosis (HR:1.76, p = 0.049). No statistically significant independent prognostic factors for PFS were found. Receiving osimertinib before platinum-pemetrexed treatment did not impact PFS with platinum-pemetrexed treatment (HR: 1.11, p = 0.64).

CONCLUSION

Postoperative recurrence, first-line EGFR-TKI PFS ≥12 months and osimertinib treatment after platinum-pemetrexed predicted better OS, while BMI <18.5 predicted worse OS. Osimertinib treatment before platinum-pemetrexed treatment did not affect the efficacy of platinum-pemetrexed.

Efficacy of Epidermal Growth Factor Receptor-Tyrosine Kinase Inhibitors in Metastatic Non-Small Cell Lung Cancer Patients with Poor Performance Status and Epidermal Growth Factor Receptor Mutations: Findings from the Japanese Lung Cancer Registry Database

BACKGROUND

In advanced non-small cell lung cancer (NSCLC) patients harboring epidermal growth factor receptor (EGFR) mutations, those with impaired performance status (PS) treated with EGFR-tyrosine kinase inhibitors (TKIs) have demonstrated comparable activities to good-PS patients. Due to the limited sample size and inclusion of older adult patients with good PS, these findings may not accurately depict the efficacy of EGFR-TKI in poor-PS patients. We investigated the benefit of EGFR-TKIs in this population and identified relevant prognostic factors.

PATIENTS AND METHODS

This nationwide prospective registry study included 9872 patients with local or advanced NSCLC. Outcomes were compared between poor- and good-PS patients treated with EGFR-mutated lung cancer therapies.

RESULTS

Of 9872 NSCLC patients, 1965 (19.9%) had EGFR mutations, with 1846 (93.9%) presenting common EGFR mutations. Poor PS (PS score ≥ 3) was noted in 171 patients (8.7%) and identified as an independent prognostic factor; those with poor PS had a significantly lower 1-year survival rate. The median overall survival (OS) for EGFR-TKI-treated good-PS patients was 31.5 (95% confidence interval, 29.6-33.4) months. Among poor-PS patients with EGFR mutations, 135 (78.9%) of whom were treated with EGFR-TKI had an OS of 15.5 (12.7-18.3) months, while those receiving only supportive care had an OS of 2.5 (1.4-3.6) months (P < .001). Hypoalbuminemia (< 3.5 g/dL), liver metastasis, and uncommon EGFR mutations were associated with poor prognosis.

CONCLUSION

Poor PS at diagnosis was rare and associated with limited EGFR-TKI efficacy and a dismal prognosis. Liver metastasis and hypoalbuminemia may reduce EGFR-TKI efficacy in these patients.

YES1 as a potential target to overcome drug resistance in EGFR-deregulated non-small cell lung cancer

Epidermal growth factor receptor (EGFR)-tyrosine kinase inhibitors (TKIs) such as gefitinib and osimertinib have primarily been used as first-line treatments for patients with EGFR-activating mutations in non-small cell lung cancer (NSCLC). Novel biomarkers are required to distinguish patients with lung cancer who are resistant to EGFR-TKIs. The aim of the study is to investigate the expression and functional role of YES1, one of the Src-family kinases, in EGFR-TKI-resistant NSCLC. YES1 expression was elevated in gefitinib-resistant HCC827 (HCC827/GR) cells, harboring EGFR mutations. Moreover, HCC827/GR cells exhibited increased reactive oxygen species (ROS) levels compared to those of the parent cells, resulting in the phosphorylation/activation of YES1 due to oxidation of the cysteine residue. HCC827/GR cells showed elevated expression levels of YES1-associated protein 1 (YAP1), NF-E2-related factor 2 (Nrf2), cancer stemness-related markers, and antioxidant proteins compared to those of the parent cells. Knockdown of YES1 in HCC827/GR cells suppressed YAP1 phosphorylation, leading to the inhibition of Bcl-2, Bcl-xL, and Cyclin D1 expression. Silencing YES1 markedly attenuated the proliferation, migration, and tumorigenicity of HCC827/GR cells. Dasatinib inhibited the proliferation of HCC827/GR cells by targeting YES1-mediated signaling pathways. Furthermore, the combination of gefitinib and dasatinib demonstrated a synergistic effect in suppressing the proliferation of HCC827/GR cells. Notably, YES1- and Nrf2-regulated genes showed a positive regulatory relationship in patients with lung cancer and in TKI-resistant NSCLC cell lines. Taken together, these findings suggest that modulation of YES1 expression and activity may be an attractive therapeutic strategy for the treatment of drug-resistant NSCLC.

Differential prognostic value of tumor and plasma T790M mutations in EGFR TKI-treated advanced NSCLC

Background

Substitution of methionine for threonine at codon 790 (T790M) of epidermal growth factor receptor (EGFR) represents the major mechanism of resistance to EGFR tyrosine kinase inhibitors (TKIs) in EGFR-mutant non-small-cell lung cancer. We determined the prognostic impact and association of secondary T790M mutations with the outcomes of osimertinib and chemotherapy.

Methods

Patients (n = 460) progressing from first-line EGFR-TKI treatment were assessed. Tissue and/or liquid biopsies were used to determine T790M status; post-progression overall survival (OS) was analyzed.

Results

Overall, 143 (31.1%) patients were T790M positive, 95 (20.7%) were T790M negative, and 222 (48.2%) had unknown T790M status. T790M status [T790M positive versus T790M negative: hazard ratio (HR) 0.48 (95% confidence interval (CI), 0.32-0.70); p < 0.001, T790M unknown versus T790M negative: HR 1.97 (95% CI, 1.47-2.64); p < 0.001] was significantly associated with post-progression OS. T790M positivity rates were similar for tissue (90/168, 53.6%) and liquid (53/90, 58.9%) biopsies (Fisher's exact test, p = 0.433). Tumor T790M-positive patients had significantly longer post-progression OS than tumor T790M-negative patients (34.1 versus 17.1 months; log-rank test, p = 8 × 10-5). Post-progression OS was similar between plasma T790M-positive and -negative patients (17.4 versus not reached; log-rank test, p = 0.600). In tumor T790M-positive patients, post-progression OS was similar after osimertinib and chemotherapy [34.1 versus 29.1 months; log-rank test, p = 0.900; HR 1.06 (95% CI, 0.44-2.57); p = 0.897].

Conclusion

T790M positivity predicts better post-progression OS than T790M negativity; tumor T790M positivity has a stronger prognostic impact than plasma T790M positivity. Osimertinib and chemotherapy provide similar OS benefits in patients with T790M-positive tumors.

Tissue or liquid rebiopsy? A prospective study for simultaneous tissue and liquid NGS after first-line EGFR inhibitor resistance in lung cancer

INTRODUCTION

According to current International Association for the Study of Lung Cancer guideline, physicians may first use plasma cell-free DNA (cfDNA) methods to identify epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor (TKI)-resistant mechanisms (liquid rebiopsy) for lung cancer. Tissue rebiopsy is recommended if the plasma result is negative. However, this approach has not been evaluated prospectively using next-generation sequencing (NGS).

METHODS

We prospectively enrolled patients with lung cancer with first-line EGFR-TKI resistance who underwent tissue rebiopsy. The rebiopsied tissues and cfDNA were sequenced using targeted NGS, ACTDrug®+, and ACTMonitor®Lung simultaneously. The clinicopathological characteristics and treatment outcomes were analyzed.

RESULTS

Totally, 86 patients were enrolled. Twenty-six (30%) underwent tissue biopsy but the specimens were inadequate for NGS. Among the 60 patients with paired tissue and liquid rebiopsies, two-thirds (40/60) may still be targetable. T790M mutations were found in 29, including 14 (48%) only from tissue and 5 (17%) only from cfDNA. Twenty-four of them were treated with osimertinib, and progression-free survival was longer in patients without detectable T790M in cfDNA than in patients with detectable T790M in cfDNA (p = 0.02). For the 31 T790M-negative patients, there were six with mesenchymal-epithelial transition factor (MET) amplifications, four with ERBB2 amplifications, and one with CCDC6-RET fusion. One with MET amplification and one with ERBB2 amplification responded to subsequent MET and ERBB2 targeting agents respectively.

CONCLUSIONS

NGS after EGFR-TKI resistance may detect targetable drivers besides T790M. To do either liquid or tissue NGS only could miss patients with T790M. To do tissue and liquid NGS in parallel after EGFR-TKI resistance may find more patients with targetable cancers.

Brain metastasis, EGFR mutation subtype and generation of EGFR-TKI jointly influence the treatment outcome of patient with EGFR-mutant NSCLC

Non-small cell lung cancer (NSCLC) with epidermal growth factor receptor (EGFR) mutation is brain metastasis (BM)-prone. We determined the impact of this hallmark, along with EGFR subtype and generation of tyrosine kinase inhibitor (TKI) treatment, on patients' outcome. 553 metastatic EGFR-mutant NSCLC patients received front-line EGFR-TKI treatment. Progression-free survival (PFS), overall survival (OS) and secondary T790M rate were analysed. BM was observed in 211 (38.2%) patients. BM (HR 1.20 [95% CI 0.99-1.48]; p = 0.053), ECOG PS 0-1 (HR 0.71 [95% CI 0.54-0.93]; p = 0.014) and afatinib treatment (HR 0.81 [95% CI 0.66-0.99]; p = 0.045) were associated with PFS. Afatinib-treated patients without BM demonstrated a significantly longer PFS (16.3 months) compared to afatinib-treated patients with BM (13.7 months) and to gefitinib/erlotinib-treated patients with (11.1 months) or without BM (14.2 months; p < 0.001). CNS-only progression trended higher in afatinib-treated patients. ECOG PS 0-1 (HR 0.41 [95% CI 0.31-0.56]; p < 0.001) and EGFR L858R mutation (HR 1.46 [95% CI 1.13-1.88]; p = 0.003), but not BM, were the predictors for OS. BM (OR 2.02 [95% CI 1.02-4.08]; p = 0.040), afatinib treatment (OR 0.26 [95% CI 0.12-0.50]; p < 0.001) and EGFR L858R mutation (OR 0.55 [95% CI 0.28-1.05]; p = 0.070) were associated with secondary T790M rate. In BM patients, gefitinib/erlotinib-treated ones with 19 deletion mutation and afatinib-treated ones with L858R mutation had the highest and the lowest T790M rate (94.4% vs. 27.3%, p < 0.001), respectively. BM and generation of EGFR-TKI jointly impact PFS and secondary T790M rate in patients with EGFR-mutant NSCLC, whereas OS was mainly associated with EGFR subtype.

Sequential treatment in advanced epidermal growth factor receptor-mutated lung adenocarcinoma patients receiving first-line bevacizumab combined with 1st/2nd-generation EGFR-tyrosine kinase inhibitors

Introduction

The clinical outcomes of sequential treatment of advanced epidermal growth factor receptor (EGFR)-mutated non-small cell lung cancer (NSCLC) patients with first-line bevacizumab combined with 1st/2nd-generation EGFR-TKIs are unclear. Thus, we aimed to analyze the outcomes of these patients.

Methods

Between January 2015 and December 2020, data for 102 advanced EGFR-mutated lung adenocarcinoma patients receiving first-line bevacizumab combined with erlotinib or afatinib followed by treatments at multiple institutions were retrospectively analyzed. All patients with progressive disease (PD) after first-line therapy underwent secondary T790M mutation detection.

Results

The secondary T790M mutation positive rate of all study patients was 57.9%. First-line erlotinib use and progression-free survival (PFS) after first-line therapy > 12 months were positively associated with the T790M mutation (P <0.05). The response rates (RRs) to second-line treatments were 51.7% and 22.7% for the osimertinib and nonosimertinib groups, respectively (P = 0.001). The median PFS associated with second-line osimertinib and nonosimertinib therapy was 13.7 and 7.1 months, respectively (hazard ratio (HR) = 0.38; 95% confidence interval (CI), 0.23-0.63; P< 0.001). Patients with a secondary T790M mutation receiving second-line osimertinib treatment had a median overall survival (OS) of 54.3 months, and the median OS was 31.9 months for non-T790M-mutated patients receiving second-line nonosimertinib treatments (HR = 0.36; CI: 0.21-0.62, P < 0.001).

Conclusion

The majority of acquired resistance to first-line bevacizumab combined with 1st/2nd-generation EGFR-TKIs is associated with the T790M mutation. Sequential osimertinib treatment in patients with positive secondary T790M mutation is associated with better outcomes among these patients.

Decoding the key compounds and mechanism of Shashen Maidong decoction in the treatment of lung cancer

BACKGROUND

Lung cancer is a malignant tumour with the fastest increase in morbidity and mortality around the world. The clinical treatments available have significant side effects, thus it is desirable to identify alternative modalities to treat lung cancer. Shashen Maidong decoction (SMD) is a commonly used traditional Chinese medicine (TCM) formula for treating lung cancer in the clinic. While the key functional components (KFC) and the underlying mechanisms of SMD treating lung cancer are still unclear.

METHODS

We propose a new integrated pharmacology model, which combines a novel node-importance calculation method and the contribution decision rate (CDR) model, to identify the KFC of SMD and to deduce their mechanisms in the treatment of lung cancer.

RESULTS

The enriched effective Gene Ontology (GO) terms selected from our proposed node importance detection method could cover 97.66% of enriched GO terms of reference targets. After calculating CDR of active components in key functional network, the first 82 components covered 90.25% of the network information, which were defined as KFC. 82 KFC were subjected to functional analysis and experimental validation. 5-40 μM protocatechuic acid, 100-400 μM paeonol or caffeic acid exerted significant inhibitory activity on the proliferation of A549 cells. The results show that KFC play an important therapeutic role in the treatment of lung cancer by targeting Ras, AKT, IKK, Raf1, MEK, and NF-κB in the PI3K-Akt, MAPK, SCLC, and NSCLC signaling pathways active in lung cancer.

CONCLUSIONS

This study provides a methodological reference for the optimization and secondary development of TCM formulas. The strategy proposed in this study can be used to identify key compounds in the complex network and provides an operable test range for subsequent experimental verification, which greatly reduces the experimental workload.

Monitoring of T790M in plasma ctDNA of advanced EGFR-mutant NSCLC patients on first- or second-generation tyrosine kinase inhibitors

BACKGROUND

The T790M mutation is the major resistance mechanism to first- and second-generation TKIs in EGFR-mutant NSCLC. This study aimed to investigate the utility of droplet digital PCR (ddPCR) for detection of T790M in plasma circulating tumor DNA (ctDNA), and explore its impact on prognosis.

METHODS

This prospective study enrolled 80 advanced lung adenocarcinoma patients treated with gefitinib, erlotinib, or afatinib for TKI-sensitizing mutations between 2015 and 2019. Plasma samples were collected before TKI therapy and at tri-monthly intervals thereafter. Genotyping of ctDNA for T790M was performed using a ddPCR EGFR Mutation Assay. Patients were followed up until the date of death or to the end of 2021.

RESULTS

Seventy-five of 80 patients experienced progressive disease. Fifty-three (71%) of 75 patients underwent rebiopsy, and T790M mutation was identified in 53% (28/53) of samples. Meanwhile, plasma ddPCR detected T790M mutation in 23 (43%) of 53 patients. The concordance rate of T790M between ddPCR and rebiopsy was 76%, and ddPCR identified 4 additional T790M-positive patients. Ten (45%) of 22 patients who did not receive rebiopsy tested positive for T790M by ddPCR. Serial ddPCR analysis showed the time interval from detection of plasma T790M to objective progression was 1.1 (0-4.1) months. Compared to 28 patients with rebiopsy showing T790M, the overall survival of 14 patients with T790M detected solely by ddPCR was shorter(41.3 [95% CI, 36.6-46.0] vs. 26.6 months [95% CI, 9.9-43.3], respectively).

CONCLUSION

Plasma ddPCR-based genotyping is a useful technology for detection and monitoring of the key actionable genomic alteration, namely, T790M, in patients treated with gefitinib, erlotinib, or afatinib for activating mutations, to achieve better patient care and outcome.

Biomarkers involved in the proliferation of the odontogenic keratocyst, glandular odontogenic cyst and botryoid odontogenic cyst

INTRODUCTION

Odontogenic cysts are a heterogeneous group of lesions with varied clinical behavior.

OBJECTIVE

To analyze the expression of the epidermal growth factor receptor (EGFR), Cyclin D1, and transcription factor SOX2 in the odontogenic epithelium evaluating the cell cycle control and cystic expansion.

METHODS

This was a cross-sectional study including 40 cases, 20 odontogenic keratocysts (OKC), 10 botryoid odontogenic cysts (BOC), and 10 glandular odontogenic cysts (GOC).

RESULTS

All cases of OKC, BOC, and GOC were positive for EGFR in all layers of the cyst lining. The highest expression of nuclear Cyclin D1 was observed in the suprabasal layer of OKCs and in the basal and suprabasal layers of GOC and BOC (p < 0.001). In addition, SOX2 was only expressed in the suprabasal layer of OKCs.

CONCLUSION

The high expression of EGFR in the cyst membrane suggests that EGF stimulates epithelial proliferation in BOCs, and the high expression of SOX2 in OKCs may be related to the presence of stem cells in the lesion. Cyclin D1 is related to cell cycle disruption in G1-S contributing to stimulates epithelial proliferation of OKCs and GOCs and BOCs.

Afatinib and Dacomitinib Efficacy, Safety, Progression Patterns, and Resistance Mechanisms in Patients with Non-Small Cell Lung Cancer Carrying Uncommon EGFR Mutations: A Comparative Cohort Study in China (AFANDA Study)

(1) Background: Afatinib has been approved for patients with non-small cell lung cancer (NSCLC) carrying major uncommon epidermal growth factor receptor gene (EGFR) mutations. Dacomitinib, another second-generation tyrosine kinase inhibitor, has also shown promising potential for uncommon EGFR mutations. However, no comparative study has been conducted. (2) Methods: Two cohorts were employed: the AFANDA cohort, an ambispective cohort including 121 patients with uncommon EGFR mutations admitted to two tertiary hospitals in China, and an external validation afatinib cohort (ex-AC), extracted from the Afatinib Uncommon EGFR Mutations Database (N = 1140). The AFANDA cohort was divided into an afatinib cohort (AC) and a dacomitinib cohort (DC) for internal exploration. Objective response rate (ORR), progression-free survival (PFS), and adverse events (AEs) were assessed for comparison. Progression patterns and resistance mechanisms were explored. (3) Results: In total, 286 patients with advanced NSCLC carrying uncommon EGFR mutations treated with afatinib or dacomitinib were enrolled, including 79 in the AFANDA cohort (44 in the DC, 35 in the AC) and 207 in the ex-AC. In internal exploration, the ORR of the DC was significantly higher than that of the AC (60.5 vs. 26.7%, p = 0.008), but there was no significant difference in median PFS between the DC and the AC (12.0 months vs. 10.0 months, p = 0.305). Multivariate analysis confirmed an independent favorable effect of dacomitinib on PFS (hazard ratio (HR), 1.909; p = 0.047). In external validation, multivariate analysis confirmed the independent prognostic role of dacomitinib in PFS (HR, 1.953; p = 0.029). Propensity score matching analysis confirmed the superiority of dacomitinib over afatinib in terms of PFS in both univariate and multivariate analyses. Toxicity profiling analysis suggested more G1 (p = 0.006), but fewer G3 (p = 0.036) AEs in the DC than in the AC. Progression patterns revealed that the incidence of intracranial progression in the AC was significantly higher than that in the DC (50 vs. 21.1%, p = 0.002). Drug resistance analysis indicated no significant difference in the occurrence of T790M between the AC and the DC (11.8 vs. 15.4%, p = 0.772). (4) Conclusions: Compared with afatinib, dacomitinib demonstrated a more favorable activity with manageable toxicity and different progression patterns in patients with NSCLC carrying uncommon EGFR mutations.

Real-world treatment patterns and outcomes among patients with advanced non-small-cell lung cancer with spindle cell and/or giant cell carcinoma

Objectives

A definitive diagnosis of pulmonary sarcomatoid carcinoma cannot be made with small biopsies. In clinical practice, a diagnosis of advanced non-small-cell lung cancer with spindle cell and/or giant cell carcinoma (NSCLCsg), or possible sarcomatoid carcinoma, is acceptable. Therefore, we aimed to investigate the treatment patterns and outcomes of advanced NSCLCsg.

Materials and methods

Between 01 January 2012 and 01 April 2021, patients with pathologically proven advanced NSCLCsg were enrolled. The choice of treatment was based on clinician discretion.

Results

In all, 101 patients with advanced NSCLCsg were enrolled. In total, 77 (76.2%) patients received at least one line of systemic therapy; 44 patients (43.1%) had received platinum doublet chemotherapy; 27 (26.7%) patients had been treated with targeted therapies; and 23 patients (22.8%) had been given an immune checkpoint inhibitor (ICI). The median overall survival (OS) was 6.3 months [95% confidence interval (CI): 3.6-9.0 months]. Excluding patients without systemic therapy, patients who had received an ICI had better OS (median: 18.2 months) than those who had not (median 3.8 months, log-rank test p = 0.002). No significant difference in OS was detected between patients who had or had not received platinum doublet chemotherapy (log-rank test p = 0.279), or targeted therapy (log-rank test p = 0.416). Having received any systemic therapy [hazard ratio (HR): 0.33, 95% CI: 0.18-0.61, p < 0.0001) and ICI (HR: 0.38, 95% CI: 0.19-0.78, p = 0.008) were independent factors for better OS. Patients with programmed death ligand-1 (PD-L1) expression ⩾50% had better OS than those with PD-L1 expression <50% (HR: 0.51, 95%: 0.30-0.86, p = 0.012).

Conclusion

Although advanced NSCLCsg has a poor survival outcome, our results showed that ICI may prolong OS in patients with advanced NSCLCsg. Further prospective studies are warranted to gain more understanding of the role of ICI in this specific patient population.

Efficacy and potential resistance mechanisms of afatinib in advanced non-small cell lung cancer patients with EGFR G719X/L861Q/S768I

BACKGROUND

Afatinib is the only currently approved EGFR-tyrosine kinase inhibitors for advanced non-small cell lung cancer (NSCLC) patients with EGFR G719X/L861Q/S768I. However, there are limited real-world data concerning the benefits and resistance mechanisms of afatinib in patients with these nonclassical mutations. To fill this gap, the present study was conducted.

METHODS

All NSCLC patients treated with afatinib were screened, and patients with EGFR G719X/L861Q/S768I were enrolled into the analysis. Either tumor tissue or blood specimens were detected by the commercial next-generation sequencing (NGS) panels or amplification-refractory mutation system (ARMS)-polymerase chain reaction (PCR) to figure out the mutation genotype.

RESULTS

A total of 106 advanced NSCLC patients with EGFR G719X/L861Q/S768I received afatinib treatment. The benefits of afatinib exhibited heterogeneity in different mutation genotypes. Notably, at baseline, NGS testing was performed in 59 patients, and TP53 was the most frequently coexisting mutation. Patients with TP53 mutations obtained fewer survival benefits than those with TP53 wild-type. A total of 68 patients ultimately experienced progression, and 27 patients received NGS testing to clarify the potential resistance mechanisms. EGFR-T790M, CDK4 amplification, FGFR1 amplification, PIK3CA, MET amplification, RET fusions, HER2, and BRAF mutations were identified in three (11.1%), three (11.1%), three (11.1%), three (11.1%), three (11.1%), one (3.7%), one (3.7%), and one (3.7%) of the cases, respectively. Five patients underwent ARMS-PCR testing for detecting EGFR-T790M mutation, and only one patient was T790M-positive.

CONCLUSIONS

The present study elucidated the differential benefits of afatinib within different mutation genotypes and first revealed the spectrum of potential resistance mechanisms in patients with EGFR G719X/L861Q/S768I. The results of this study may provide practical clinical information that can guide optimal treatment in this setting.

Real-world efficacy of osimertinib in previously EGFR-TKI treated NSCLC patients without identification of T790M mutation

BACKGROUND

The efficacy of osimertinib in previously EGFR-TKI-treated NSCLC without identification of T790M mutational status remains unclear in real-world practice.

PATIENTS AND METHODS

417 patients had stage III-IV NSCLC harboring EGFR mutation and 154 out of 417 patients receiving osimertinib as ≥ second-line EGFR-TKI were identified. The time to treatment failure and risk of death were analyzed.

RESULTS

Higher risk of death was found in EGFR-mutant patients with age ≥ 65 years, non-adenocarcinoma, no surgery or radiation, non-exon 19 deletion/exon 21 L858R, higher ECOG PS (2-4), PD-L1 expression ≥ 50%, and bone/liver/adrenal metastasis (all p < 0.05). Osimertinib as ≥ second-line TKI in patients with/without identification of T790M revealed lower risk of death compared to first-line first/second generation TKI without subsequent osimertinib (p = 0.0002; 0.0232, respectively). However, osimertinib-treated patients with T790M did not have superior survival than those without (p = 0.2803). A higher risk of treatment failure for osimertinib was found in males, patients with first-line TKI duration ≤ 12 months, BMI drop > 10%, and PD-L1 expression ≥ 50% (All p < 0.05). Nonetheless, osimertinib as ≥ second-line TKI in patients without identification of 790 M did not have higher risk of treatment failure than those with T790M (p = 0.1236).

CONCLUSIONS

This study demonstrates that osimertinib as second line or subsequent TKI in EGFR-TKI-treated patients without identification of T790M revealed lower risk of death compared to first-line first/second generation TKI without subsequent osimertinib, in real-world practice. Additionally, EGFR-mutant patients with PD-L1 expression ≥ 50% had a higher risk of treatment failure for osimertinib and worse overall survival than those with PD-L1 expression < 50%. These results suggest that osimertinib as second line or subsequent TKI may be a potential alternative option for the treatment of patients without identification of T790M and PD-L1 expression ≥ 50% is associated with a significantly poor outcome in patients receiving osimertinib.

Resistance to TKIs in EGFR-Mutated Non-Small Cell Lung Cancer: From Mechanisms to New Therapeutic Strategies

Resistance to tyrosine kinase inhibitors (TKIs) of the epidermal growth factor receptor (EGFR) in advanced mutant Non-Small Cell Lung Cancer (NSCLC) constitutes a therapeutic challenge. This review intends to summarize the existing knowledge about the mechanisms of resistance to TKIs in the context of EGFR mutant NSCLC and discuss its clinical and therapeutic implications. EGFR-dependent and independent molecular pathways have the potential to overcome or circumvent the activity of EGFR-targeted agents including the third-generation TKI, osimertinib, negatively impacting clinical outcomes. CNS metastases occur frequently in patients on EGFR-TKIs, due to the inability of first and second-generation agents to overcome both the BBB and the acquired resistance of cancer cells in the CNS. Newer-generation TKIs, TKIs targeting EGFR-independent resistance mechanisms, bispecific antibodies and antibody-drug conjugates or combinations of TKIs with other TKIs or chemotherapy, immunotherapy and Anti-Vascular Endothelial Growth Factors (anti-VEGFs) are currently in use or under investigation in EGFR mutant NSCLC. Liquid biopsies detecting mutant cell-free DNA (cfDNA) provide a window of opportunity to attack mutant clones before they become clinically apparent. Overall, EGFR TKIs-resistant NSCLC constitutes a multifaceted therapeutic challenge. Mapping its underlying mutational landscape, accelerating the detection of resistance mechanisms and diversifying treatment strategies are essential for the management of the disease.

Review of epidermal growth factor receptor-tyrosine kinase inhibitors administration to non-small-cell lung cancer patients undergoing hemodialysis

Non-small-cell lung cancer (NSCLC) causes significant mortality worldwide. Patients with chronic renal failure have an increased risk of developing lung cancer. NSCLC Patients with chronic renal failure undergoing hemodialysis (HD) often exhibit poor performance, and chemotherapy is generally contraindicated. Oral epidermal growth factor receptor (EGFR)-tyrosine kinase inhibitors (TKIs) are effective treatment agents for NSCLC patients. However, the benefits and adverse effects of EGFR-TKIs in NSCLC undergoing HD are known. There are no clinical studies on the effects of EGFR-TKIs on NSCLC patients undergoing HD. We reviewed all previous case reports about EGFR-TKIs in NSCLC patients undergoing HD. It is difficult to design studies about the effects of EGFR-TKIs in patients undergoing HD, and this review is quite important. EGFR-TKIs are well tolerated in patients undergoing HD. The main routes of elimination of EGFR-TKIs are metabolism via the liver, and renal elimination is minor. The recommended doses and pharmacokinetics of these EGFR-TKIs for patients undergoing HD are similar to those for patients with normal renal function. The plasma protein binding of EGFR-TKIs is very high, and it is not necessary to adjust the dose after HD. In conclusion, EGFR-TKIs are effective and well tolerated in patients undergoing HD.

Optimizing Patient Outcomes Through Sequential EGFR TKI Treatment in Asian Patients With EGFR Mutation-Positive NSCLC

Patients from Asia with non-small-cell lung cancer (NSCLC) often have mutations in the epidermal growth factor receptor (EGFR) gene. While an increasing number of EGFR tyrosine kinase inhibitors (TKIs) are now available for patients with EGFR mutation-positive NSCLC, most patients inevitably develop resistance to the treatment. Evidence from clinical studies suggests that treatment outcomes and resistance mechanisms vary depending on the choice of TKI therapy in the first-line setting. Hence, it is important to develop optimal treatment sequencing strategies that can provide maximum survival benefit for the patient. In this review we present clinical evidence in Asian patients with NSCLC for various EGFR TKIs, with the goal of supporting the optimization of treatment sequencing.

Comparison of T790M Acquisition After Treatment With First- and Second-Generation Tyrosine-Kinase Inhibitors: A Systematic Review and Network Meta-Analysis

Background

Lung adenocarcinoma is a common disease with a high mortality rate. Epidermal growth factor receptor (EGFR) mutations are found in adenocarcinomas, and oral EGFR-tyrosine kinase inhibitors (EGFR-TKIs) show good responses. EGFR-TKI therapy eventually results in resistance, with the most common being T790M. T790M is also a biomarker for predicting resistance to first- and second-generation EGFR-TKIs and is sensitive to osimertinib. The prognosis was better for patients with acquired T790M who were treated with osimertinib than for those treated with chemotherapy. Therefore, T790M mutation is important for deciding further treatment and prognosis. Previous studies based on small sample sizes have reported very different T790 mutation rates. We conducted a meta-analysis to evaluate the T790M mutation rate after EGFR-TKI treatment.

Methods

We systematic reviewed the electronic databases to evaluate the T790M mutation rate after treatment with first-generation (gefitinib, erlotinib, and icotinib) and second-generation (afatinib and dacomitinib) EGFR-TKIs. Random-effects network meta-analysis and single-arm meta-analysis were conducted to estimate the T790M mutation rate of the target EGFR-TKIs.

Results

A total of 518 studies were identified, of which 29 were included. Compared with afatinib, a higher odds ratio (OR) of the T790M mutation rate was observed after erlotinib [OR = 1.48; 95% confidence interval (CI):1.09–2.00] and gefitinib (OR = 1.45; 95% CI: 1.11–1.90) treatments. An even OR of the T790M mutation rate was noted after icotinib treatment (OR = 0.91, 95% CI: 0.46–1.79) compared with that after afatinib. The T790M mutation rate was significantly lower with afatinib (33%) than that with gefitinib (49%) and erlotinib treatments (47%) (p < 0.001). The acquired T790M mutation rate in all participants was slightly lower in Asians (43%) than that in Caucasians (47%).

Conclusions

Erlotinib and gefitinib had a higher OR for the T790M mutation than afatinib. The T790M mutation rate was significantly lower in afatinib than in gefitinib and erlotinib. T790M is of great significance because osimertinib shows a good prognosis in patients with T790M mutation.

Systematic Review Registration

PROSPERO, identifier CRD42021257824.

State-of-the-Art Molecular Oncology of Lung Cancer in Taiwan

Lung cancers are life-threatening malignancies that cause great healthcare burdens in Taiwan and worldwide. The 5-year survival rate for Taiwanese patients with lung cancer is approximately 29%, an unsatisfactorily low number that remains to be improved. We first reviewed the molecular epidemiology derived from a deep proteogenomic resource in Taiwan. The nuclear factor erythroid 2-related factor 2 (NRF2)antioxidant mechanism was discovered to mediate the oncogenesis and tumor progression of lung adenocarcinoma. Additionally, DNA replication, glycolysis and stress response are positively associated with tumor stages, while cell-to-cell communication, signaling, integrin, G protein coupled receptors, ion channels and adaptive immunity are negatively associated with tumor stages. Three patient subgroups were discovered based on the clustering analysis of protein abundance in tumors. The first subgroup is associated with more advanced cancer stages and visceral pleural invasion, as well as higher mutation burdens. The second subgroup is associated with EGFR L858R mutations. The third subgroup is associated with PI3K/AKT pathways and cell cycles. Both EGFR and PI3K/AKT signaling pathways have been shown to induce NRF2 activation and tumor cell proliferation. We also reviewed the clinical evidence of patient outcomes in Taiwan given various approved targeted therapies, such as EGFR-tyrosine kinase inhibitors and anaplastic lymphoma kinase (ALK)inhibitors, in accordance with the patients’ characteristics. Somatic mutations occurred in EGFR, KRAS, HER2 and BRAF genes, and these mutations have been detected in 55.7%, 5.2%, 2.0% and 0.7% patients, respectively. The EGFR mutation is the most prevalent targetable mutation in Taiwan. EML4-ALK translocations have been found in 9.8% of patients with wild-type EGFR. The molecular profiling of advanced NSCLC is critical to optimal therapeutic decision-making. The patient characteristics, such as mutation profiles, protein expression profiles, drug-resistance profiles, molecular oncogenic mechanisms and patient subgroup systems together offer new strategies for personalized treatments and patient care.

Risk Stratification Using a Novel Nomogram for 2190 EGFR-Mutant NSCLC Patients Receiving the First or Second Generation EGFR-TKI

Simple Summary

No comprehensive and simple prognostic model based on pretreatment factors exists for patients with epidermal growth factor receptor mutation-positive (EGFRm+) non-small cell lung cancer (NSCLC) undergoing EGFR-tyrosine kinase inhibitors (EGFR-TKIs). A total of 11 independent prognostic factors were identified by multivariate analysis, including performance status, morphology, mutation, stage, EGFR-TKIs, and metastasis to liver, brain, bone, pleura, adrenal gland, and distant lymph nodes. We established a nomogram based on independent pretreatment factors and used it to stratify EGFRm+ NSCLC patients undergoing EGFR-TKI treatment into five different risk groups for survival using recursive partitioning analysis. The performance of this nomogram was good and feasible, providing clinicians and patients with additional information for evaluating therapeutic options.

Abstract

Epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs) are the standard treatment for EGFR mutation-positive (EGFRm+) non-small cell lung cancer (NSCLC). This study aimed to create a novel nomogram to help physicians suggest the optimal treatment for patients with EGFRm+ NSCLC. Records of 2190 patients with EGFRm+ NSCLC cancer who were treated with EGFR-TKIs (including gefitinib, erlotinib, and afatinib) at the branches of a hospital group between 2011 and 2018 were retrospectively reviewed. Their clinicopathological characteristics, clinical tumor response, progression-free survival (PFS), and overall survival (OS) data were collected. Univariate and multivariate analyses were performed to identify potential prognostic factors to create a nomogram for risk stratification. Univariate analysis identified 14 prognostic factors, and multivariate analysis confirmed the pretreatment independent factors, including Eastern Cooperative Oncology Group performance status, morphology, mutation, stage, EGFR-TKIs (gefitinib, erlotinib, or afatinib), and metastasis to liver, brain, bone, pleura, adrenal gland, and distant lymph nodes. Based on these factors, a novel nomogram was created and used to stratify the patients into five different risk groups for PFS and OS using recursive partitioning analysis. This risk stratification can provide additional information to clinicians and patients when determining the optimal therapeutic options for EGFRm+ NSCLC.

Comparison of Different Tyrosine Kinase Inhibitors for Treatment of Poor Performance Status Patients with EGFR-Mutated Lung Adenocarcinoma

Simple Summary

Epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs) are standard treatments in patients with EGFR-mutated lung adenocarcinoma. However, the clinical data regarding EGFR-TKI efficacy in patients with poor performance status (PS ≥ 2) are limited. We reviewed the clinical outcomes and safety of EFGR-TKI use in patients with poor PS and identified the independent and favorable prognostic factors for progression-free survival and overall survival. We found that patients treated with 40 mg afatinib had better survival results, although only a non-significant trend toward superiority was observed in the multivariable analysis. Dose adjustment was an independent prognostic factor for PFS and OS. This study provided evidence of the use of EGFR-TKIs for patients with poor PS.

Abstract

The aim of this retrospective study was to investigate the tolerability and survival outcomes of epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs) treatment in patients with a performance status ≥ 2. The data for 517 patients treated with EGFR-TKIs between January 2011 and January 2018 at a regional hospital in northern Taiwan were analyzed. Clinical and pathological features were collected, and univariate as well as multivariable analyses were undertaken to identify potential prognostic factors. The overall objective response rate, median progression-free survival (PFS), and median overall survival (OS) were 56.3%, 11.4 months, and 15.3 months, respectively. The mutation status (exon 19 deletion), locally advanced disease, dose adjustment, and the lack of liver and pleural metastasis were independent and favorable prognostic factors for PFS. Age < 60 years, mutation status (exon 19 deletion), dose adjustment, and lack of lung, liver, and no pleural metastasis were independent and favorable prognostic factors for OS. GFR-TKIs demonstrated acceptable efficacy and safety in the current cohort. Dose adjustment was identified as an independent prognostic factor for both PFS and OS, regardless of which EGFR-TKIs were used. The current research provided novel evidence of the clinical prescription of frontline EGFR-TKIs for EGFR-mutated lung adenocarcinoma patients with a PS score ≥2.

A Phase IIIb Open-Label, Single-Arm Study of Afatinib in EGFR TKI-Naïve Patients with EGFRm+ NSCLC: Final Analysis, with a Focus on Patients Enrolled at Sites in China

BACKGROUND

Afatinib has been shown as a suitable option for the treatment of epidermal growth factor receptor mutation-positive (EGFRm+) non-small-cell lung cancer (NSCLC) in randomized controlled trials. However, patients treated in real-world clinical practice, including elderly patients, and those with brain metastases or poor Eastern Cooperative Oncology Group (ECOG) performance statuses, are often excluded from these studies.

OBJECTIVE

To report the final results, with a particular focus on patients enrolled in China, from a prospective phase IIIb, "near real-world" study of afatinib in tyrosine kinase inhibitor (TKI)-naïve Asian patients with EGFRm+ NSCLC.

PATIENTS AND METHODS

NCT01953913 was conducted at 34 centers across Asia. Entry criteria were broad to reflect real-world settings. Patients received afatinib 40 mg/day until tumor progression, lack of clinical benefit, or poor tolerability. Assessments included safety, time to symptomatic progression (TTSP), and progression-free survival (PFS).

RESULTS

541 patients were treated, of whom 412 were enrolled in China. Dose reductions were implemented in 28.7% of patients overall, and 17.7% of patients from China. Safety findings were consistent with phase III studies of afatinib. Median TTSP in all patients was 14.0 months (95% CI 12.9-15.9), and median PFS was 12.1 months (95% CI 11.0-13.6). Median TTSP (13.8 months, 95% CI 12.7-16.1) and PFS (11.4 months, 95% CI 10.9-13.7) were similar in patients from China to the overall population. Among patients from China who had dose reductions, TTSP was numerically longer than in those who did not (16.4 vs. 13.8 months; P = 0.0703), while PFS was significantly longer (13.9 vs. 11.1 months; P = 0.0275). Among patients from China with brain metastases, TTSP was numerically shorter than in those without (11.0 vs. 14.4 months; P = 0.0869), whereas PFS was significantly shorter (9.2 vs. 12.9 months; P = 0.0075).

CONCLUSIONS

Safety data for afatinib when used in a "near real-world" setting in patients with EGFRm+ NSCLC was consistent with the known safety profile of afatinib. Supporting efficacy data of afatinib were provided in all patients, and in those enrolled in China. Tolerability-guided afatinib dose reduction allowed patients to remain on treatment and continue to experience clinical benefit.

TRIAL REGISTRATION NUMBER AND DATE OF REGISTRATION

NCT01953913 (1 October 2013).

Integration of Genomic Profiling and Organoid Development in Precision Oncology

Precision oncology involves an innovative personalized treatment strategy for each cancer patient that provides strategies and options for cancer treatment. Currently, personalized cancer medicine is primarily based on molecular matching. Next-generation sequencing and related technologies, such as single-cell whole-transcriptome sequencing, enable the accurate elucidation of the genetic landscape in individual cancer patients and consequently provide clinical benefits. Furthermore, advances in cancer organoid models that represent genetic variations and mutations in individual cancer patients have direct and important clinical implications in precision oncology. This review aimed to discuss recent advances, clinical potential, and limitations of genomic profiling and the use of organoids in breast and ovarian cancer. We also discuss the integration of genomic profiling and organoid models for applications in cancer precision medicine.

Uncommon EGFR mutations in non-small-cell lung cancer: A systematic literature review of prevalence and clinical outcomes

Mutations in exons 18-21 of the epidermal growth factor receptor gene (EGFR) can confer sensitivity to EGFR-tyrosine kinase inhibitors (EGFR-TKIs) in patients with non-small-cell lung cancer (NSCLC). Deletions in exon 19 or the exon 21 L858R substitution comprise approximately 85% of mutations, but comparatively few data are available on the remaining "uncommon" mutations. We conducted a systematic literature review to identify evidence on uncommon EGFR mutations in locally advanced/metastatic NSCLC (PROSPERO registration number: CRD42019126583). Electronic screening and congress searches identified studies published in 2012-2020 including patients with locally advanced/metastatic NSCLC and uncommon EGFR mutations (excluding T790M). We assessed the prevalence of uncommon mutations (in studies using direct sequencing of exons 18-21), and compared response to treatment and progression-free survival (PFS) in patients with common versus uncommon mutations and in those with exon 20 mutations versus other uncommon mutations. We identified 64 relevant studies. Uncommon mutations constituted 1.0-18.2% of all EGFR mutations, across 10 studies. The most frequently reported uncommon mutations were G719X (0.9-4.8% of all EGFR mutations), exon 20 insertions (Ex20ins; 0.8-4.2%), L861X (0.5-3.5%), and S768I (0.5-2.5%). Patients with common mutations typically experienced better treatment response and longer PFS on EGFR-TKIs than patients with uncommon mutations; Ex20ins mutations were associated with less favourable outcomes than other uncommon mutations. This review shows that uncommon mutations may comprise a clinically significant proportion of the EGFR mutations occurring in NSCLC, and highlights disparities in EGFR-TKI sensitivity between different uncommon mutations.

Multicellular Effects of STAT3 in Non-small Cell Lung Cancer: Mechanistic Insights and Therapeutic Opportunities

Non-small cell lung cancer (NSCLC) is the most common type of lung cancer and accounts for 85% of lung cancer cases. Aberrant activation of the Signal Transducer and Activator of Transcription 3 (STAT3) is frequently observed in NSCLC and is associated with a poor prognosis. Pre-clinical studies have revealed an unequivocal role for tumor cell-intrinsic and extrinsic STAT3 signaling in NSCLC by promoting angiogenesis, cell survival, cancer cell stemness, drug resistance, and evasion of anti-tumor immunity. Several STAT3-targeting strategies have also been investigated in pre-clinical models, and include preventing upstream receptor/ligand interactions, promoting the degradation of STAT3 mRNA, and interfering with STAT3 DNA binding. In this review, we discuss the molecular and immunological mechanisms by which persistent STAT3 activation promotes NSCLC development, and the utility of STAT3 as a prognostic and predictive biomarker in NSCLC. We also provide a comprehensive update of STAT3-targeting therapies that are currently undergoing clinical evaluation, and discuss the challenges associated with these treatment modalities in human patients.

High Incidence of C797S Mutation in Patients With Long Treatment History of EGFR Tyrosine Kinase Inhibitors Including Osimertinib

Introduction

Although treatment with osimertinib confers survival benefits in patients with lung cancer with the EGFR T790M mutation, the mechanism of acquired resistance to osimertinib remains poorly understood. We conducted a prospective observational study to identify the mechanism on the basis of repeated tissue biopsies.

Methods

Patients with EGFR-mutated advanced lung cancer with a T790M mutation detected on a tissue biopsy underwent a rebiopsy after developing acquired resistance to osimertinib. Nucleic acids extracted from the biopsy samples were subjected to targeted resequencing (Oncomine Comprehensive Assay), and circulating cell-free DNA (ccfDNA) was analyzed by CAncer Personalized Profiling by deep Sequencing (AVENIO ctDNA Surveillance Kit).

Results

Between November 2016 and March 2020, a total of 87 patients were screened. Among them, 44 developed acquired resistance. Of these, 19 samples from rebiopsies and 12 from preosimertinib biopsies were able to be analyzed by an Oncomine Comprehensive Assay. A ccfDNA analysis was performed in 16 patients. Regarding the mechanisms of acquired resistance, structural change in EGFR, namely, C797S, G796S, or L792V, was the most frequent alteration, being observed in 57.9% of the cases. MET gain was observed in 31.6% of the cases, and gains in cell cycle genes were observed in 26.3% of the cases. In addition, we identified GAS6 gain and an ATM mutation in a patient with small-cell transformation and a BRAF V600E mutation in a patient with oligoprogressive disease.

Conclusions

A repeated tissue biopsy and a ccfDNA analysis were useful in analyzing the mechanisms underlying acquired resistance. A long treatment history of EGFR TKIs may result in a high percentage of EGFR structural change.

Association of EGFR Tyrosine Kinase Inhibitor Treatment With Progression-Free Survival Among Taiwanese Patients With Advanced Lung Adenocarcinoma and EGFR Mutation

Background: There is limited data on the relative survival rate of first-line therapy of gefitinib, erlotinib (first-generation epidermal growth factor receptor-tyrosine kinase inhibitor [EGFR-TKI]), and afatinib (second-generation EGFR-TKI) in patients with EGFR-mutated advanced lung adenocarcinoma in real-world data, especially in the Asian population. This study aimed to compare the relative survival rate of gefitinib, erlotinib, and afatinib in patients with EGFR-mutated advanced lung adenocarcinoma by real-world data in Taiwan. Methods: This retrospective cohort population-based study included untreated adult patients diagnosed with advanced lung adenocarcinoma who were identified in the Taiwan National Health Insurance Research Database between 2014 and 2017. The date of EGFR-mutated advanced lung adenocarcinoma diagnosis was referred as index date. This outcome evaluated overall survival (OS) and time to treatment failure (TTF) between gefitinib, erlotinib, and afatinib. Switching EGFR-TKIs or chemotherapy and new development of brain metastases were proxies of TTF. Estimated relative treatment effects on OS and TTF among EGFR-TKIs were adjusted by inverse probability of treatment weighting (IPTW) in Cox proportional hazards model. Propensity score (PS) matched pair analyses were performed as sensitivity analyses. Results: The study cohort included 3,695 patients initiated with gefitinib, 3,310 with erlotinib, and 3,041 with afatinib. The mean age among the three treatment groups was 70.4 (±11.6), 66.8 (±11.6), and 64.3 (±11.4) years, and the female percentage was 70.4, 58.6, and 57.7%, respectively. Afatinib showed longer median OS than gefitinib (23.9 vs. 21.3 months; adjusted hazard ratio (aHR), 0.87; p < 0.001) and erlotinib (23.9 vs. 21.8 months; aHR, 0.87; p = 0.001). Consistent results were observed with TTF outcomes. For patients with brain metastases at diagnosis, afatinib showed similar OS with erlotinib (p = 0.917) but superior to gefitinib (p = 0.028). PS matching had similar results with IPTW adjustment in the study population. Conclusion: Afatinib as first-line therapy had better survival outcomes for EGFR-mutated advanced lung adenocarcinoma than gefitinib and erlotinib in the Taiwan population. Both erlotinib and afatinib demonstrated superior treatment effect in patients with initial brain metastases than gefitinib.

First- or second-generation epidermal growth factor receptor tyrosine kinase inhibitors in a large, real-world cohort of patients with non-small cell lung cancer

Background

There are limited comparisons of first- and second-generation EGFR tyrosine kinase inhibitors (TKIs) in large, real-world cohorts of non-small cell lung cancer (NSCLC) patients with epidermal growth factor receptor (EGFR) mutations.

Methods

Patients with advanced NSCLC (N = 612) with common EGFR mutations receiving first-line gefitinib/erlotinib and afatinib were grouped and propensity-score matched. Progression-free survival (PFS), overall survival (OS) and secondary T790M mutations were analyzed.

Results

The gefitinib/erlotinib and afatinib groups each contained 206 patients after matching. Compared with gefitinib/erlotinib, patients receiving afatinib achieved longer median PFS (16.3 versus 14.2 months; log-rank test p = 0.020) and had a lower risk of progression [hazard ratio (HR) 0.73 (95% confidence interval (CI), 0.57-0.94); p = 0.017]. Median OS (37.3 versus 34.2 months; log-rank test p = 0.500) and reduction in risk of death [HR 0.89 (95% CI, 0.65-1.23); p = 0.476] did not differ significantly between groups. T790M positivity was significantly higher in the gefitinib/erlotinib than afatinib group (70.9% versus 44.6%, p < 0.001). Multivariate analysis demonstrated that afatinib was independently associated with lower T790M positivity [odds ratio (OR) 0.27 (95% CI, 0.14-0.53); p < 0.001], whereas ⩾12 months PFS after EGFR-TKI treatment [OR 3.00 (95% CI, 1.56-5.98); p = 0.001] and brain metastasis [OR 2.12 (95% CI, 1.08-4.26); p = 0.030] were associated with higher T790M positivity. Sequential third-generation EGFR-TKI treatment was administered to 63 patients, in whom median OS after the second-third-generation and first-third-generation EGFR-TKI sequences were 38.8 and 29.1 months, respectively.

Conclusion

Compared with gefitinib/erlotinib, afatinib had a higher treatment efficacy and a lower secondary T790M positivity in a large, real-world cohort of Asian patients with EGFR-mutated NSCLC.

Feasibility and effectiveness of afatinib for poor performance status patients with EGFR-mutation-positive non-small-cell lung cancer: a retrospective cohort study

Background

Afatinib is one of the standard treatments for patients with epidermal growth factor receptor (EGFR)-mutated non-small-cell lung cancer (NSCLC). However, data on the use of afatinib in patients with poor performance status (PS ≥ 2) are limited. This study aimed to retrospectively review the clinical outcomes and safety of afatinib treatment in EGFR-mutation-positive (EGFRm+) NSCLC patients with PS ≥ 2.

Methods

The data for 62 patients who were treated at Linkou Chang Gung Memorial Hospital from January 2010 to August 2019 were retrospectively reviewed. Patients’ clinicopathological features were obtained, and univariate and multivariate analyses were performed to identify possible prognostic factors. Data on adverse events were collected to evaluate general tolerance for afatinib therapy.

Results

Until February 2020, the objective response rate, disease control rate, median progression-free survival (PFS), and overall survival (OS) were 58.1% (36/62), 69.4% (43/62), 8.8 months, and 12.9 months, respectively. The absence of liver metastasis (PFS: p = 0.044; OS: p = 0.061) and good disease control (p < 0.001 for PFS and OS) were independent favorable prognostic factors for PFS and OS. Bone metastasis (p = 0.036) and dose modification (reduction/interruption, p = 0.021) were predictors of disease control.

Conclusion

Afatinib demonstrated acceptable efficacy and safety in the current cohort. This study provided evidence to support the use of afatinib as a first-line treatment in EGFRm+ NSCLC patients with poor PS.

Sequential treatment of afatinib and osimertinib or other regimens in patients with advanced non-small-cell lung cancer harboring EGFR mutations: Results from a real-world study in South Korea

OBJECTIVES

The optimal sequence for the administration of epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs) for treating non-small cell lung cancer (NSCLC) is still unclear. This study aimed to evaluate the efficacy of sequential afatinib and osimertinib treatment in patients with NSCLC harboring EGFR mutations.

MATERIALS AND METHODS

Electronic records of patients with EGFR-mutated NSCLC, who were administered afatinib and osimertinib (group A) or other chemotherapy (group B) between October 2014 and 2019, across 16 hospitals in South Korea were reviewed. The primary outcome, time on treatment (TOT), secondary outcome, and overall survival (OS) were estimated using the Kaplan-Meier method and log-rank test. Multivariate analyses were performed using the Cox proportional hazards model.

RESULTS

Of the 737 patients who received frontline afatinib treatment, 324 with complete records were selected (group A: 126, group B: 198). All patients in group A were T790M positive after afatinib, while patients in group B were all negative or unknown. The median TOT was 35.4 months (95% confidence interval [CI]: 27.7-45.6) in group A and 20.8 months (95% CI: 19.4-24.0) in group B. The median TOT with afatinib was 13.0 months (95% CI: 12.0-13.9) overall and 15.7 months (95% CI: 13.9-17.3) in group A. The 2- and 3-year survival rates were 86.0 and 69.3% in group A and 75.9 and 55.3% in group B, respectively.

CONCLUSION

Sequential afatinib and osimertinib treatment resulted in better survival rates than treatment with afatinib followed by other chemotherapies.

Erlotinib as a salvage treatment after gefitinib failure for advanced non-small-cell lung cancer patients with brain metastasis: A successful case report and review

RATIONALE

The guidelines recommended gefitinib as a first-line targeted treatment for stage IV non-small-cell lung cancer (NSCLC) patients with EGFR mutations. However, resistance to gefitinib ensues invariably and there is little evidence as for the effectiveness of subsequent salvage treatment for patients without T790m mutation. The case is to evaluate the efficacy of erlotinib, another EGFR-TKI, after failed first-line use of gefitinib.

PATIENT CONCERNS

We described a 55-year-old man with good performance status (PS).

DIAGNOSES

He was histopathologically diagnosed stage IV lung adenocarcinoma with EGFR mutations in November 2018.

INTERVENTIONS

He was administrated with gefitinib daily (250 mg) for activating epidermal growth factor receptor (EGFR) mutations (exon 19 deletions,19del), and combined with platinum-based dual-drug chemotherapy. During the target treatments, the optimal efficacy evaluation was partial remission (PR) with a 12-month progression-free survival (PFS) time. Later, the intracranial progression of the patient rendered the treatment change to erlotinib.

OUTCOMES

It is surprising that the tumor lesion in brain as well as lung relieved obviously. His progression-free survival (PFS)was nearly 11 months, and the overall survival (OS)was>36 months up to now. The adverse events were tolerable.

LESSIONS

This case manifests that re-biopsy of advanced or recurrent NSCLC is beneficial to make a better therapeutic regimen, and erlotinib can be used as a salvage treatment after gefitinib failure.

The impact of different first-line EGFR-TKIs on the clinical outcome of sequential osimertinib treatment in advanced NSCLC with secondary T790M

The impact of different first-line epidermal growth factor receptor (EGFR)-tyrosine kinase inhibitor (TKI)s to the clinical efficacy of osimertinib in EGFR-mutant non-small-cell lung cancer (NSCLC) patients with acquired T790M was still unclear. We enrolled 733 advanced EGFR-mutant NSCLC patients with gefitinib, erlotinib or afatinib as first-line EGFR-TKIs treatment for analysis. 373 patients received re-biopsies after progressive disease to first-line EGFR-TKIs treatment, and the total positive rate of T790M was 51.7%. 151 patients who harbored T790M received osimertinib as subsequent treatment. Among them, the median progression-free survival (PFS) of first-line EGFR-TKI (PFS1) was 14.0 months, and the median PFS of osimertinib (PFS2) was 10.1 months. The median PFS1 + PFS2 was 27.5 months, and the median overall survival from first-line EGFR-TKI was 61.3 months. Concerning different first-line EGFR-TKIs, the median PFS2 was 10.9 months in the gefitinib group, 10.0 months in the erlotinib group, and 6.7 months in the afatinib group (p = 0.534). The median PFS1 + PFS2 was 27.7 months, 26.8 months and 24.0 months in the gefitinib, erlotinib, and afatinib group, respectively (p = 0.575). In conclusion, both first-generation and second-generation EGFR-TKIs sequential osimertinib treatment provided good clinical efficacy in advanced EGFR-mutant NSCLC patients with acquired T790M mutation.

Targeting STAT3 signaling overcomes gefitinib resistance in non-small cell lung cancer

Lung cancer is one of the most aggressive cancers with poor prognosis and high resistance rate. The family of signal transducer and activator of transcriptions (STATs) appears to modulate resistance in non-small cell lung cancer (NSCLC). In this work, we demonstrated that STAT3/ZEB1 is a critical axis in gefitinib resistance. STAT3-targeted inhibition therefore is a new potential therapeutic strategy for gefitinib resistance in lung cancer. Our small molecule screening identified a relatively specific STAT3-targeted inhibitor, LL1. Pharmacological and biochemical studies indicated that LL1 block the activation of STAT3 via inhibiting its phosphorylation. Further in vitro and in vivo studies elucidated that LL1 sensitizes the resistance cells to gefitinib through depleting STAT3 activity and blocking STAT3/ZEB1 signaling pathways. Little toxicity of LL1 was observed in animal models. All these favorable results indicated that LL1 is a chemotherapeutic adjuvant for gefitinib resistance in NSCLC.

Osimertinib versus afatinib in patients with T790M-positive, non-small-cell lung cancer and multiple central nervous system metastases after failure of initial EGFR-TKI treatment

Background

The purpose of this study was to compare the efficacy of osimertinib (OSI) versus afatinib (AFA) in patients with T790M-positive, non-small-cell lung cancer (NSCLC) and multiple central nervous system (CNS) metastases after failure of initial epidermal growth factor receptor tyrosine kinase inhibitor (EGFR-TKI) treatment.

Methods

Consecutive patients with T790M-positive NSCLC and multiple CNS metastases after failure of initial EGFR-TKI treatment were retrospectively identified from our medical institution during 2016–2018 and underwent either oral 80 daily OSI or oral 40 daily AFA every 3 weeks for up to 6 cycles, until disease progression, intolerable adverse events (AEs), or death. The co-primary endpoints were overall survival (OS) and progression-free survival (PFS).

Results

The cohort consisted of 124 patients (OSI: n = 60, mean age = 64.24 years [SD: 12.33]; AFA: n = 64, mean age = 64.13 years [SD: 13.72]). After a median follow-up of 24 months (range, 3 to 28), a significant improvement in OS was detected (hazard ratio [HR] 0.59, 95% confidence interval [CI], 0.39–0.91; p = 0.0160; median, 13.7 months [95% CI, 11.1–14.8] for OSI vs 9.6 months [95% CI, 8.4–10.2] for AFA). The median duration of PFS was significantly longer with OSI than with AFA (HR 0.62; 95% CI, 0.41–0.91; p = 0.014; median, 4.5 months [95% CI, 3.5–5.7] vs 3.9 months [95% CI, 3.1–4.8]). The proportion of grade 3 or higher adverse events (AEs) was lower with OSI (22.4%) than with AFA (39.4%).

Conclusions

In patients with T790M-positive NSCLC and multiple CNS metastases after failure of initial EGFR-TKI treatment, OSI may be associated with significantly improved survival benefit compared with AFA, with a controllable tolerability profile.

Afatinib as First-Line Treatment in Asian Patients with EGFR Mutation-Positive NSCLC: A Narrative Review of Real-World Evidence

Epidermal growth factor receptor tyrosine kinase inhibitors (EGFR TKIs) are a standard of care in the first-line treatment of patients with EGFR mutation-positive metastatic non-small-cell lung cancer (NSCLC). EGFR mutations are relatively common in Asian patients with NSCLC, and there is an increasing number of studies supporting the effectiveness of the second-generation TKI afatinib in routine clinical practice in Asia. This article reviews these real-world studies investigating afatinib as first-line treatment for EGFR mutation-positive NSCLC in Asian patients. Evidence from real-world studies with afatinib in this patient population supports findings from randomized controlled trials (RCTs) showing that afatinib is associated with more favorable outcomes compared with the first-generation EGFR TKIs. The effectiveness of afatinib has also been shown in real-world studies in Asian patients with poor prognostic factors, who are often under-represented or excluded from RCTs, such as those with uncommon EGFR mutations, brain metastases, or poor performance status, and elderly patients. The tolerability profile of afatinib in the real-world setting reflects that seen in RCTs, with no new safety signals reported in real-world studies in Asian patients with EGFR mutation-positive NSCLC. Dose-modification strategies also seem to be effective in the real world, with results of the RealGido study, which included 44% Asian patients, confirming findings from prospective clinical trials showing that tolerability-guided afatinib dose modifications can reduce the incidence of adverse events without adversely affecting clinical outcomes. While further research, including clinical trial data, is needed, real-world data have also demonstrated the feasibility of sequential afatinib followed by the third-generation TKI osimertinib in T790M-positive EGFR mutation-positive patients, which showed longer overall survival. Together, these real-world results demonstrate the real-world clinical effectiveness of afatinib as first-line treatment for patients with EGFR mutation-positive NSCLC.

EGFR tyrosine kinase inhibitors for EGFR mutation-positive non-small-cell lung cancer: outcomes in Asian populations

Few data are available that have compared outcomes with different EGFR tyrosine kinase inhibitors (TKIs) specifically in Asian patients with EGFR mutation-positive non-small-cell lung cancer. In this narrative review, we have collated available data from prospective studies that have assessed first-, second- and third-generation EGFR TKIs in Asian populations, including subanalyses in individual countries (China and Japan). These data indicate that outcomes with first- and second-generation TKIs are broadly similar in Asian and non-Asian populations. However, while the third-generation EGFR TKI, osimertinib, confers significant overall survival benefit over erlotinib/gefitinib in non-Asians, this is not apparent in Asians, particularly in countries like Japan with well-resourced healthcare. Head-to-head comparisons of second- and third-generation EGFR TKIs, with OS as a primary end point, should be considered in Asia.

Factors affecting treatment selection and overall survival for first-line EGFR-tyrosine kinase inhibitor therapy in non-small-cell lung cancer

Aim: To investigate the factors associated with treatment selection and overall survival for first-line EGFR-tyrosine kinase inhibitors (EGFR-TKIs) therapy among patients with non-small-cell lung cancer. Materials & methods: We conducted a retrospective cohort study of linked administrative health databases in Ontario, Canada. Results: A total of 1011 patients received an EGFR-TKI as first-line therapy. Treatment selection and overall survival associated with these treatments were affected by age, sex, geographical residency, comorbidities and different sites of metastasis. Conclusion: Though recent approval of osimertinib offers a potential new standard of care in the first-line setting, earlier generation TKIs remain pillars in treatment of non-small-cell lung cancer therapeutic armamentarium. Our findings may contribute to optimizing treatment sequencing of EGFR-TKIs to maximize clinical benefits.

Treatment Options of First-Line Tyrosine Kinase Inhibitors and Subsequent Systemic Chemotherapy Agents for Advanced EGFR Mutant Lung Adenocarcinoma Patients: Implications From Taiwan Cancer Registry Cohort

Objectives

Large-scale, population-based real-world studies on the treatment outcomes of first-line tyrosine kinase inhibitors (TKIs) and subsequent systemic chemotherapy agents for lung adenocarcinoma (with activating epidermal growth factor receptor [EGFR] mutations) remain limited.

Materials and Methods

From March 2014 to December 2016, patients with advanced lung adenocarcinoma, identified from the Taiwan Cancer Registry were included in this study if they received any of the three TKIs as first-line treatment. The primary outcome was overall survival (OS). The secondary outcome was time-to-treatment discontinuation (TTD).

Results

A total of 4,889 patients (median age: 67 years and two-thirds with distant metastasis) were recruited (1,778 gefitinib, 1,599 erlotinib, and 1,512 afatinib users). A 1:1 propensity score (PS)-matched cohorts of 1,228 afatinib/erlotinib and 1054 afatinib/gefitinib was created. After PS matching, it was found that afatinib was not associated with better OS (afatinib vs. erlotinib, HR: 0.96, 95% CI: 0.86–1.07; afatinib vs. gefitinib, HR: 0.91, 95% CI: 0.81–1.02). In the subgroup analysis, afatinib demonstrated a survival benefit in patients with active smoking (afatinib vs. erlotinib, HR: 0.69, 95% CI: 0.51–0.93; afatinib vs. gefitinib, HR: 0.67, 95% CI: 0.48–0.94) and ECOG > 1 (afatinib vs. erlotinib, HR: 0.79, 95% CI: 0.63–0.99; afatinib vs. gefitinib, HR: 0.78, 95% CI: 0.62–0.98). A total of 41.1% (n = 1992) of first-line TKI users received subsequent chemotherapy. Among the three TKI groups, pemetrexed usage was associated with better OS compared with other chemotherapy agents, with the exception of gemcitabine in the afatinib and gefitinib groups. Pemetrexed and gemcitabine had the longest TTD of 3–4 months.

Conclusions

Among patients with EGFR mutant lung adenocarcinoma, afatinib use may not provide longer OS compared with first-generation TKIs. Afatinib may be preferably considered among patients with active smoking and should not be withheld among those with worse performance status. With 40% of patients receiving subsequent chemotherapy, pemetrexed may be the preferred agent, while gemcitabine can be a reasonable alternative.

The Impact of Acquired EGFR T790M Mutation and EGFR Circulating Cell-Free DNA on Survival in Patients with Lung Adenocarcinoma Following EGFR-TKI Therapy

Objective

To utilize liquid biopsy to investigate the potential clinical factors influencing the incidence of the acquired epidermal growth factor receptor (EGFR) T790M mutation, and the impact of EGFR circulating cell-free DNA (CfDNA) on overall survival for patients with advanced EGFR-mutated adenocarcinoma resistant to first-line EGFR-tyrosine kinase inhibitor (TKI).

Methods

A retrospective study was conducted to analyze EGFR-mutated stage IIIB-IV adenocarcinoma patients who received an EGFR-TKI (gefitinib, erlotinib, or afatinib) as first-line therapy and then underwent a liquid biopsy exam at disease progression.

Results

A total of 135 patients were included, and the T790M mutation was detected in 51 patients (37.7%). The incidence of T790M mutation increased with the number of initial metastatic sites (p = 0.015). Liver metastasis (odds ratio [OR], 3.373; p = 0.017) and other metastasis (OR, 3.063; p = 0.023) were also independently correlated with T790M mutation incidence. T790M mutation was also associated with more than two progressive sites (OR, 3.382; p = 0.006), liver progression (OR, 6.204; p = 0.002), and bone progression (OR, 3.366; p = 0.004). However, central nervous system progression was inversely correlated with T790M mutation (OR, 0.183; p = 0.027). Overall survival was the longest among the patients without CfDNA, followed by those shedding T790M mutation and those shedding Del 19/L858R mutations (p = 0.005).

Conclusion

Initial metastasis to the liver and other sites may be independent factors for secondary EGFR T790M mutation. T790M-positive lung adenocarcinoma has specific progression patterns. Moreover, not having EGFR CfDNA, being positive for Del19/L858R mutations, and being positive for T790M mutation have differing impacts on overall survival for patients with advanced EGFR-mutated adenocarcinoma resistant to first-line EGFR-TKI.

Phase I study of afatinib plus bevacizumab in patients with advanced non-squamous non-small cell lung cancer harboring EGFR mutations

Background

Afatinib is a second-generation epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor (TKI). Combination therapies with first-generation EGFR-TKIs and bevacizumab have been reported to prolong progression-free survival (PFS). However, there are few data on the combination of afatinib and bevacizumab.

Methods

In this phase I trial, we evaluated the safety of afatinib plus bevacizumab in patients with advanced non-squamous non-small cell lung cancer (NSCLC) harboring EGFR mutations. This study consisted of two cohorts. In the dose-finding cohort, enrolled patients were treated with afatinib at a dose of 20, 30, or 40 mg/day (days 1-21) plus bevacizumab at a dose of 15 mg/kg (day 1) in 21-day cycles. This cohort was performed according to a 3 + 3 manner. In the expansion cohort, enrolled patients received the recommended dose (RD) based on the results of the dose-finding cohort. The serum trough concentration of afatinib was determined at the steady state.

Results

Seventeen patients were enrolled in this study (6 patients in the dose-finding cohort and 11 patients in the expansion cohort). There were no dose-limiting toxicities (DLTs) with afatinib at a dose of 30 mg/day. With afatinib at a dose of 40 mg/day, two of two patients experienced DLTs (grade 3 diarrhea) in cycle 1. With these results, afatinib at a dose of 30 mg/day plus bevacizumab at a dose of 15 mg/kg was determined as the RD. Eleven patients in the expansion cohort were treated with the RD. Common treatment-related adverse events (AEs) with the RD were diarrhea (79%), rash (71%), perionychia (64%), and stomatitis (50%). Grade 3 AEs with the RD were diarrhea (7%), perionychia (7%), and hypertension (7%). There were no grade 4/5 AEs or cases of interstitial lung disease. Dose-proportional increases in serum afatinib trough concentrations at steady state were not observed. The response rates (RRs) and disease control rates were 55% and 100% in EGFR-TKI-naïve patients. Re-biopsy was performed in eight patients after progressive disease following the study treatment, and three patients acquired a T790M mutation.

Conclusions

Afatinib at a dose of 30 mg/day plus bevacizumab at a dose of 15 mg/kg q3w is well tolerated.

First-line treatment with irreversible tyrosine kinase inhibitors associated with longer OS in EGFR mutation-positive non-small cell lung cancer

Background

Few studies have compared the efficacy of the irreversible epidermal growth factor receptor tyrosine kinase inhibitor (EGFR‐TKI), afatinib, with that of reversible EGFR‐TKIs. Therefore, this study assessed the effectiveness of afatinib, erlotinib, and gefitinib in terms of OS (overall survival) and progression‐free survival (PFS) in EGFR mutation‐positive advanced non‐small cell lung cancer (NSCLC) patients.

Methods

Patients with EGFR mutation‐positive advanced NSCLC who sought treatment from December 2013 to June 2018, at a tertiary referral center were retrospectively analyzed. These patients were treated with afatinib or a reversible EGFR‐TKI (erlotinib or gefitinib) until disease progression, intolerable adverse events, or death. The Kaplan‐Meier and log‐rank tests were then used to compare the OS and PFS of the patients. We further analyzed the survival differences among the subgroup of patients without brain metastases.

Results

Of the 363 patients enrolled, 134 and 229 received first‐line afatinib and first‐line reversible EGFR‐TKI, respectively. Those given afatinib had better OS (39.3 vs. 26.0 months; HR 0.65, P = 0.033) and PFS (14.1 vs.11.2 months; HR 0.58, P < 0.001). Of the 246 patients without brain metastases, 93 and 153 received first‐line afatinib and a first‐line reversible EGFR‐TKI, respectively. Those given afatinib had a better OS (52.6 vs. 24.9 months; HR 0.62, P = 0.0030) and PFS (17.7 vs. 11.1 months; HR 0.51, P < 0.001). The survival benefit was more significant in the subgroup of patients with L858R substitutions.

Conclusions

The results indicated that afatnib resulted in significantly better OS and PFS than gefitnib and erlotinib for EGFR mutation‐positive advanced NSCLC patients without brain metastases.

Key points

Significant findings of the study

Afatnib resulted in significantly better overall survival and progression‐free survival than gefitnib and erlotinib for EGFR mutation‐positive advanced non‐small cell lung cancer patients without brain metastases.

What this study adds

This study helps fill the gap in our limited understanding of the differences in the efficacy of the irreversible epidermal growth factor receptor tyrosine kinase inhibitor (EGFR‐TKI), afatinib, with that of reversible EGFR‐TKIs.

Afatinib for the first-line treatment of EGFR mutation-positive NSCLC in China: a review of clinical data

Mutations in the EGFR gene are particularly prevalent among Chinese patients with non-small-cell lung carcinoma. Six EGFR tyrosine kinase inhibitors are approved for the first-line treatment of EGFR mutation-positive non-small-cell lung carcinoma in China, which poses questions about which agent is most suitable for a particular patient. In this article, we review available clinical trial and real-world data with afatinib in Chinese patients. We assess its efficacy and safety in key patient subgroups such as those with uncommon mutations or brain metastases. We also consider possible subsequent therapies following afatinib. Encouragingly, available data suggest that sequential afatinib and osimertinib confer prolonged overall time to failure of almost 4 years in Asian patients, and represents a viable option in this setting.

An Observational Study of Acquired EGFR T790M-Dependent Resistance to EGFR-TKI Treatment in Lung Adenocarcinoma Patients in Taiwan

In Taiwan, epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (EGFR-TKIs), gefitinib, erlotinib, and afatinib are served as first-line therapy for non-small lung cell cancer (NSCLC) patients with EGFR sensitizing mutations. However, the majority of patients who initially respond to EGFR-TKIs, progress through acquiring EGFR T790M mutations (T790M), which is the most common resistant mechanism. Patients with T790M gain the opportunity of subsequent treatment with third-generation EGFR-TKI, osimertinib. This study aimed to evaluate the association between prior EGFR-TKI therapy and incidence of acquired T790M resistance in lung adenocarcinoma patients who have progressed on first/second-generation EGFR-TKI therapy. This retrospective study included lung adenocarcinoma patients who had a radiographically-confirmed progressive disease under EGFR-TKI treatment and had re-biopsy samples for T790M testing from seven medical centers in Taiwan from June 2013 to December 2018. Patients harboring de novo T790M or using more than one EGFR-TKI were excluded. Of the 407 patients enrolled, the overall T790M acquisition rate was 52.8%. The patients treated with gefitinib, erlotinib or afatinib had a statistically significant difference in the T790M rates (59.9, 45.5, and 52.7%, respectively; p = 0.037) after disease progression. Patients with common baseline EGFR mutations (Del-19 and L858R) (p = 0.005) and longer treatment duration with EGFR-TKIs (p < 0.001) had higher chances of T790M acquisition. Multivariate logistic regression analysis further showed that patients with common baseline EGFR mutations, gefitinib (compared to erlotinib) administration, and longer treatment duration with EGFR-TKIs had higher T790M incidence. There was no significant difference in the incidence of acquired T790M between different re-biopsy tissue samples or complications. In conclusion, this study showed that patients who progressed from gefitinib treatment, bearing common EGFR mutations, and with longer EGFR-TKI treatment duration had increased incidence of T790M acquisition and, therefore, were suitable for subsequent osimertinib treatment.

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.

Advances in targeting acquired resistance mechanisms to epidermal growth factor receptor tyrosine kinase inhibitors

Next-generation sequencing (NGS) of tumor samples and circulating tumor DNA has revolutionized diagnostic and therapeutic strategies in lung cancer. The identification of the epidermal growth factor receptor (EGFR) oncogenic driver has translated into successful therapy of advanced lung cancer using EGFR tyrosine kinase inhibitors (TKI). Unfortunately, responses are limited by acquired mechanisms of resistance. We review herein the current landscape of acquired resistance mechanisms to EGFR-TKI therapy and recent advances in therapeutic strategies to overcome acquired resistance.

Complex EGFR mutations with secondary T790M mutation confer shorter osimertinib progression-free survival and overall survival in advanced non-small cell lung cancer

OBJECTIVES

Osimertinib is active against epidermal growth factor receptor (EGFR) T790M-mutated non-small cell lung cancer (NSCLC). However, its efficacy against complex EGFR mutations with T790M has not been evaluated.

MATERIALS AND METHODS

In order to detect complex EGFR mutations, we consecutively sequenced cancer tissues by RNA reverse transcription polymerase chain reaction. Patients with advanced NSCLC with activating EGFR mutation and secondary T790M who received osimertinib were enrolled. Patients' clinicopathologic characteristics, prior treatment details, and osimertinib treatment outcomes were analyzed.

RESULTS

Totally, 165 sequenced patients were analyzed. Eleven (7%) of them had complex EGFR mutations with T790M. The osimertinib response rate was 27%. They had a shorter progression-free survival (PFS) (median, 2.9 and 9.7 months, p < 0.001) and overall survival (OS) (median, 17.8 and 31.0 months, p = 0.01) than patients with a single EGFR mutation with T790M. After osimertinib failure, seven patients received rebiopsy with molecular analysis. Four lost the T790M, two transformed to small cell and one acquired C797S. Moreover, taking the median as the demarcation, patients received shorter prior EGFR tyrosine kinase inhibitor (TKI) treatment duration had a shorter osimertinib PFS (median, 7.3 and 13.8 months, p < 0.001) and OS (median, 21.5 and 36.7 months, p = 0.003). Multivariate Cox regression analysis confirmed complex EGFR mutations and prior EGFR TKI treatment duration were independent factors for osimertinib PFS and OS.

CONCLUSIONS

Complex EGFR mutations and shorter prior EGFR TKI treatment duration may confer shorter osimertinib PFS and OS in advanced NSCLC with secondary T790M mutation.

Prior EGFR-TKI Treatment in EGFR-Mutated NSCLC Affects the Allele Frequency Fraction of Acquired T790M and the Subsequent Efficacy of Osimertinib

BACKGROUND

The first (1G) and second (2G) generations of epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs) show differential inhibitory capacities towards EGFR T790M-mutated non-small-cell lung cancer (NSCLC) cells.

OBJECTIVE

To assess the ratio of the allele fractions of T790M (AF_T790M) to EGFR-activating mutations (AF_mEGFR) in patients treated with 1G and 2G EGFR TKIs who acquired T790M-mediated resistance and to determine the relationship between AF and the later efficacy of osimertinib.

PATIENTS AND METHODS

The efficacy of osimertinib was reviewed for 54 T790M-positive EGFR-mutated NSCLC patients grouped by the generation of prior EGFR TKI use (1G vs. 2G). AF_mEGFR and AF_T790M were determined by QuantStudio digital PCR using tissues obtained upon acquired resistance.

RESULTS

The progression-free survival (PFS; 20.3 vs. 11.6 months, p = 0.031) and the 1-year PFS rate (63.2 vs. 37.5%, p = 0.029) for osimertinib were significantly better for group 1G compared to group 2G. The ratio of AF_T790M to AF_mEGFR in group 1G was significantly higher than in group 2G (46.16 ± 5.40% vs. 25.86 ± 4.25%, p = 0.009). An unbiased analysis revealed three AF-associated clusters (ARCs) suggesting the ratio of AF_T790M to AF_mEGFR correlates with the efficacy of osimertinib. We found all patients in ARC2 having the highest ratio of AF_T790M to AF_mEGFR to have previously been treated with a 1G EGFR TKI and to show the longest osimertinib PFS compared to ARC3 (NR vs. 11.9 months, p = 0.060) and ARC1 (NR vs. 12.4 month, p = 0.045).

CONCLUSIONS

Acquired T790M fraction of EGFR-mutated NSCLC is linked to different generations of prior EGFR TKI use and the later efficacy of osimertinib.

FGFR1 Induces Acquired Resistance Against Gefitinib By Activating AKT/mTOR Pathway In NSCLC

Objective

As an epidermal growth factor, receptor-tyrosine kinase inhibitor (EGFR-TKI), gefitinib demonstrates a good therapeutic effect in patients with EGFR-mutant non-small-cell lung cancer (NSCLC). However, an overwhelming majority of these patients inevitably develop resistance against gefitinib. Unfortunately, the mechanism underlying this phenomenon is still not fully understood. Here we aim to reveal the mechanism of gefitinib resistance in NSCLC induced by FGFR1.

Materials and methods

We used high-throughput sequencing to compare the mRNA expression profiles of PC9 and PC9-GR (gefitinib-resistant) cells. The clinical significance of fibroblast growth factor receptor 1 (FGFR1) in NSCLC was also investigated using immunohistochemistry and Kaplan-Meier survival analysis. Finally, the in vitro molecular mechanisms were analyzed using confocal laser microscopy, Western blotting, transwell assay, colony formation assay, CCK-8 assay, and apoptosis assay.

Results

We observed that FGFR1 was highly expressed in NSCLC tissues and was closely associated with poor prognosis. Cytological experiments showed that FGFR1 promoted the proliferation and migration of PC9-GR cells and mediated their resistance to gefitinib. Furthermore, studies aimed at unraveling this mechanism revealed that FGFR1 activated the AKT/mTOR signaling pathway. These findings show that the FGFR1/AKT/mTOR signaling pathway plays a vital role in acquired resistance against gefitinib in NSCLC.

Conclusion

This work provides new evidence that FGFR1 functions as a key regulator of gefitinib resistance, thereby demonstrating its potential as a novel biomarker and therapeutic target for NSCLC.