First-SIGNAL: first-line single-agent iressa versus gemcitabine and cisplatin trial in never-smokers with adenocarcinoma of the lung

A network meta-analysis of nonsmall-cell lung cancer patients with an activating EGFR mutation: Should osimertinib be the first-line treatment?

BACKGROUND

Epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs) are the preferred first-line treatment for nonsmall-cell lung cancer (NSCLC) patients with an activating EGFR mutation. Osimertinib, compared with erlotinib or gefitinib, showed an improvement in progression-free survival (PFS) in a recent trial. The authors compared EGFR TKIs in terms of PFS in a network meta-analysis.

METHODS

The PubMed and Embase databases and meeting abstracts were screened for relevant studies between January 2009 and November 2017. A random-effect frequentist network meta-analysis model was conducted to assess PFS. P-score was used to rank treatment effects.

RESULTS

Eleven trials with 3145 patients and 5 TKIs (gefitinib, erlotinib, afatinib, dacomitinib, and osimertinib) were included. Heterogeneity and inconsistency existed in the network analysis. Gefitinib and erlotinib had similar effects (hazard ratio [HR] 0.94, 95% confidence interval [CI] 0.76-1.15). For all patients, the 3 TKIs with the highest probability of benefit were osimertinib, dacomitinib, and afatinib, with P-scores of 91%, 78%, and 46%, respectively. Compared with erlotinib or gefitinib, osimertinib was associated with improvement in men (HR = 0.79, 95% CI, 0.68-0.92), non-Asians (HR = 0.63, 95% CI, 0.40-0.98), smokers (HR = 0.73, 95% CI, 0.56-0.95), and those with a Del19 mutation (HR = 0.69, 95% CI, 0.54-0.90); dacomitinib and afatinib showed no improvement. Toxicity profiles mostly overlapped in all the EGFR TKIs. Toxicity-related death was rare.

CONCLUSIONS

Osimertinib was shown to be the best agent to achieve the longest PFS in NSCLC patients with an activating EGFR mutation. However, the benefit of osimertinib might be restricted to certain subgroups.

Pneumonitis in advanced non-small-cell lung cancer patients treated with EGFR tyrosine kinase inhibitor: Meta-analysis of 153 cohorts with 15,713 patients: Meta-analysis of incidence and risk factors of EGFR-TKI pneumonitis in NSCLC

PURPOSE

Pneumonitis is a significant toxicity of EGFR tyrosine kinase inhibitors (EGFR-TKI) in non-small-cell lung cancer (NSCLC) patients. We studied the incidence of pneumonitis in clinical trials of EGFR-TKI published in 2003-2017, and performed subgroups analyses to identity predisposing factors.

METHODS

Ovid-MEDLINE and EMBASE search up to 4/17/17 using the keywords, "erlotinib", "gefitinib", "afatinib", "osimertinib", and "lung cancer", resulted in a total of 153 eligible trial cohorts with 15,713 advanced NSCLC patients treated with EGFR-TKI. The pooled incidence of all-grade, high-grade, and grade 5 pneumonitis was obtained. Subgroup analyses were performed with meta-regression using study-level covariates.

RESULTS

Among the patients without prior exposure to EGFR-TKI, the overall incidence was 1.12% (95% CI:0.79-1.58%) for all-grade, 0.61% (95% CI:0.40-0.93%) for high-grade, and 0.20% (95% CI:0.11-0.38%) for grade 5 pneumonitis. The incidence was significantly higher in Japanese studies compared to studies of non-Japan origin, for all-grade (4.77% vs. 0.55%, p < 0.001), high grade (2.49% vs. 0.37%, p < 0.001), and grade 5 pneumonitis (1.00% vs. 0.18%, p < 0.001). Multivariate analyses demonstrated higher odds of pneumonitis in Japanese studies for all-grade (odds ratio [OR]: 5.04; 95% CI:3.14-8.11, p < 0.001), high-grade (OR: 4.45; 95% CI:2.50-7.93, p < 0.001), and grade 5 pneumonitis (OR: 4.55; 95% CI:2.20-9.44, p < 0.001) compared to others, after adjusting for types of EGFR-TKI and lines of therapy. In patients with EGFR retreatment analyzed separately, the pooled incidence was 1.13% (95% CI:0.40-3.15%) for all-grade, 0.49% (95% CI:0.21-1.11%) for high-grade, and 0.16% (95% CI:0.04-0.65%) for grade 5 pneumonitis.

CONCLUSIONS

The overall incidence of EGFR-TKI pneumonitis was 1.12% in patients without prior exposure to EGFR-TKI, and 1.13% in EGFR-TKI retreatment group. The cohorts from Japan had significantly higher incidence of pneumonitis, providing insights for further mechanistic studies.

Factors that Predict Clinical Benefit of EGFR TKI Therapy in Patients with EGFR Wild-Type Lung Adenocarcinoma

Background

Epidermal growth factor receptor (EGFR) mutations in non-small cell lung cancers have emerged as key predictive biomarkers in EGFR tyrosine kinase inhibitor (TKI) treatment. However, a few patients with wild-type EGFR also respond to EGFR TKIs. This study investigated the factors predicting successful EGFR TKI treatment in lung adenocarcinoma patients with wild-type EGFR.

Methods

We examined 66 patients diagnosed with lung adenocarcinoma carrying wide-type EGFR who were treated with EGFR TKIs. The EGFR gene copy number was assessed by silver in situ hybridization (SISH). We evaluated the clinical factors and EGFR gene copy numbers that are associated with a favorable clinical response to EGFR TKIs.

Results

The objective response rate was 12.1%, while the disease control rate was 40.9%. EGFR SISH analysis was feasible in 23 cases. Twelve patients tested EGFR SISH-positive, and 11 were EGFR SISH-negative, with no significant difference in tumor response and survival between EGFR SISH-positive and -negative patients. The overall median progression-free survival (PFS) and overall survival (OS) of 66 patients were 2.1 months and 9.7 months, respectively. Female sex and Eastern Cooperative Oncology Group (ECOG) performance status (PS) of 0–1 were independent predictors of PFS. ECOG PS 0–1 and a low tumor burden of extrathoracic metastasis were independent predictors of good OS.

Conclusion

Factors such as good PS, female sex, and low tumor burden may predict favorable outcomes following EGFR TKI therapy in patients with EGFR wild-type lung adenocarcinoma. However, EGFR gene copy number was not predictive of survival.

Irreversible tyrosine kinase inhibition of epidermal growth factor receptor with afatinib in EGFR activating mutation-positive advanced non-small-cell lung cancer

Despite recent advances in the systemic therapy of non-small-cell lung cancer (nsclc), the prognosis for stage iv disease remains poor. The discovery of targetable mutations has led to new treatment options. The most common mutations, the EGFR activating mutations, are present in about 50% of Asian patients and up to 15% of white patients. First-generation reversible epidermal growth factor receptor (egfr) tyrosine kinase inhibitors (tkis) have led to improved survival in patients positive for EGFR activating mutations, but resistance eventually leads to disease progression. The irreversible egfr tki afatinib was developed to counter such resistance. The clinical efficacy of afatinib has been shown in first-line studies comparing it with both cytotoxic chemotherapy and first-generation egfr tkis. Afatinib has also shown continued benefit beyond progression while a patient is taking an egfr inhibitor. Furthermore, its toxicity profile is both predictable and manageable. The results of the principal clinical trials assessing afatinib are reviewed here.

Resistance to epidermal growth factor receptor tyrosine kinase inhibitors, T790M, and clinical trials

Tumours with sensitizing mutations in the EGFR gene constitute a distinct molecular subgroup of non-small-cell lung cancers (nsclcs) that benefit from precision medicine. First- and second-generation epidermal growth factor receptor (egfr) tyrosine kinase inhibitors (tkis) are recommended as upfront therapy for EGFR-mutated advanced nsclc and, compared with chemotherapy, have resulted in superior progression-free survival, improved tumour response rates, and improved quality of life. However, resistance inevitably develops, and the third-generation tki osimertinib has been approved to target the gatekeeper EGFR mutation T790M, which is responsible for resistance in 60% of cases. Multiple drivers of tki resistance have now been identified, and many new drugs are in development. With respect to this rapidly evolving field, our review highlights the current status of treatment options for patients with EGFR-mutated advanced nsclc, focusing especially on identified causes of resistance, challenges, and clinical trials aiming to improve outcomes in this patient population.

Methodological comparison of the allele refractory mutation system and direct sequencing for detecting EGFR mutations in NSCLC, and the association of EGFR mutations with patient characteristics

Gefitinib is effective for patients with non-small cell lung cancer (NSCLC) with a mutation in the epidermal growth factor receptor (EGFR) gene, which makes the detection of EGFR mutations a critical step prior to determining a treatment schedule. Therefore, the present study determined the EGFR mutation status in patients with NSCLC using an allele refractory mutation system (ARMS) and analyzed the detection ratio for different specimen types. A total of 1,596 NSCLS samples were collected and EGFR gene mutations were detected on exons 18-21 using ARMS and direct sequencing. The concordance of two methods reached 89.21%, with a total mutation rate of 45.55% (727/1,596), in which the mutation rate in lung adenocarcinoma samples was markedly increased compared with squamous cell carcinoma (51.77 vs. 8.68%). In patients with lung adenocarcinoma, EGFR mutations were more frequent in female patients than male patients (65.53 vs. 39.80%, P<0.01); there was no observable difference depending on age. Similar results were obtained for squamous cell carcinoma. In the present study, certain rare mutations were also identified; these may be subjects for further study. The impact of different sample types on the consistency between the methods was determined to be insignificant. ARMS is a more applicable approach for large-scale clinical detection than direct sequencing, and we hypothesize that ARMS may replace direct sequencing if the drawbacks of ARMS, including its narrow detection range, can be amended.

Oncogene-addicted non-small cell lung cancer and immunotherapy

A majority of non-small cell lung cancer (NSCLC), especially adenocarcinomas, harbour at least one oncogenic driver mutation that can potentially be a target for therapy. The treatment of these oncogene-addicted tumors has dramatically changed the outcome of these patients, where tyrosine kinase inhibitors (TKIs) of mutated epidermal growth factor receptor (EGFR) and rearranged anaplastic lymphoma kinase (ALK) have paved the way for a new era of precision cancer medicine. Another paradigm shift in the treatment of NSCLC, as well as numerous other tumor types, has been the introduction of immunotherapy (IO) with immune checkpoint inhibitors targeting mainly programmed cell death-1 (PD-1) or its ligand PDL-L1, where studies have demonstrated an increased survival versus standard treatment with chemotherapy, both in the first- and second-line setting. However, the role of IO in oncogene-addicted NSCLC is still unclear where most clinical data come from subgroup analyses with low number of patients in larger randomized trials, and these data do not support the use of IO after TKI in this category of NSCLC patients. The purpose of this review is to summarize the existing evidence about the use of IO in oncogenic-addicted NSCLC and highlight the issues that should be addressed in the future in order to define the role of IO for these patients.

Value of 18F-FDG PET/CT for predicting EGFR mutations and positive ALK expression in patients with non-small cell lung cancer: a retrospective analysis of 849 Chinese patients

PURPOSE

Epidermal growth factor receptor (EGFR) mutations and the anaplastic lymphoma kinase (ALK) rearrangement are the two most common druggable targets in non-small cell lung cancer (NSCLC). However, genetic testing is sometimes unavailable. Previous studies regarding the predictive role of 18F-FDG PET/CT for EGFR mutations in NSCLC patients are conflicting. We investigated whether or not 18F-FDG PET could be a valuable noninvasive method to predict EGFR mutations and ALK positivity in NSCLC using the largest patient cohort to date.

METHODS

We retrospectively reviewed and included 849 NSCLC patients who were tested for EGFR mutations or ALK status and subjected to 18F-FDG PET/CT prior to treatment. The differences in several clinical characteristics and three parameters based on 18F-FDG PET/CT, including the maximal standard uptake value (SUVmax) of the primary tumor (pSUVmax), lymph node (nSUVmax) and distant metastasis (mSUVmax), between the different subgroups were analyzed. Multivariate logistic regression analysis was performed to identify predictors of EGFR mutations and ALK positivity.

RESULTS

EGFR mutations were identified in 371 patients (45.9%). EGFR mutations were found more frequently in females, non-smokers, adenocarcinomas and stage I disease. Low pSUVmax, nSUVmax and mSUVmax were significantly associated with EGFR mutations. Multivariate analysis demonstrated that pSUVmax < 7.0, female sex, non-smoker status and adenocarcinoma were predictors of EGFR mutations. The receiver operating characteristic (ROC) curve yielded area under the curve (AUC) values of 0.557 and 0.697 for low pSUVmax alone and the combination of the four factors, respectively. ALK-positive patients tended to have a high nSUVmax. Younger age and distant metastasis were the only two independent predictors of ALK positivity.

CONCLUSION

We demonstrated that low pSUVmax is associated with mutant EGFR status and could be integrated with other clinical factors to enhance the discriminability on the EGFR mutation status in some NSCLC patients whose EGFR testing is unavailable.

Higher expression of miR-133b is associated with better efficacy of erlotinib as the second or third line in non-small cell lung cancer patients

Epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (gefitinib, erlotinib and afatinib) are indicated as first-line therapy in patients with non-small cell lung cancer (NSCLC) whose tumors harbor activating mutations in the EGFR gene. Erlotinib is also used in second and third-line therapy for patients whose tumors have wild type EGFR but to date there are no validated biomarkers useful to identify which patients may benefit from this treatment. The expression level of four miRNAs: miR-133b, -146a, -7 and -21 which target EGFR was investigated by real-time PCR in tumor specimens from NSCLC patients treated with erlotinib administered as the second or third line. We found that miR-133b expression level better discriminated responder from non-responder patients to erlotinib. Higher levels of miR-133b in NSCLCs were associated with longer progression-free survival time of patients. Functional analyses on miR-133b through transfection of a miR-133b mimic in A549 and H1299 NSCLC cell lines indicated that increasing miR-133b expression level led to a decreased cell growth and altered morphology but did not affect sensitivity to erlotinib. The detection of miR-133b expression levels in tumors help in the identification of NSCLC patients with a better prognosis and who are likely to benefit from second and third-line therapy with erlotinib.

[Observation - An Favorable Option Forthoracic Dissemination Patients with Lung Adenocarcinoma or Squamous Carcinoma]

背景与目的

手术非晚期期患者治疗的标准治疗，但是大量的回顾性研究显示胸腔内播散型肺癌接受主病灶切除后获益明显。非标准治疗之后患者该选择何种治疗策略？本研究通过回顾性数据去探究接受了主病灶切除的胸腔内播散型肺癌患者接下来何总治疗方式更优。

方法

回顾性收集早期肺腺癌或肺鳞癌且复发模式为胸腔内播散型患者；或拟行肺癌根治术，但术中胸腔探查发现胸腔内播散，接受主病灶切除的肺腺癌或肺鳞癌患者的一般资料、病理、淋巴结状态、基因突变状态、初始治疗方式等，随访至进展、死亡或失访，记录患者无进展生存时间、总生存时间、从确诊到开始治疗的时间。通过Kaplan-Meier绘制生存曲线，Log-rank检验比较组间生存差异，Cox比例回归风险模型分析无进展生存期（progression-free survival, PFS）和总生存期（overall survival, OS）相关预后因子。

结果

研究共纳入141例患者，70例r-M1a和71例s-M1a1患者。化疗组、靶向组、随访观察组患者中位PFS分别是14.7个月、41.0个月和31.0个月（95%CI: 19.01-26.01; P < 0.001），靶向治疗组和随访观察组患者PFS差异无统计学意义（P=0.600）。中位OS分别为39.0个月、42.6个月和38.1个月（95%CI: 32.47-45.33; P=0.478）。TTI < 3个月组和TTI≥3个月组患者的中位PFS分别是15.2个月和31.0个月（95%CI: 19.01-26.06; P<0.001），中位OS分别是41.7个月和38.7个月（95%CI: 32.47-45.33; P=0.714）。多因素分析显示性别（P=0.027）、淋巴结状态（P=0.036）、初始治疗方式（P<0.001）是PFS独立预后因子。

结论

随访观察不会缩短胸腔内播散腺癌和鳞癌患者的生存时间，是一种可选的治疗策略。

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

PURPOSE

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

METHODS

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

RESULTS

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

CONCLUSION

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

Hepatotoxicity in Advanced Lung Adenocarcinoma: A Retrospective Study of 2108 Cases

The study aimed to identify the risk factors and frequency of hepatotoxicity in patients with advanced lung adenocarcinoma. Liver function tests were documented in 2108 patients with advanced (IIIB/IV) lung adenocarcinoma at a single institution who received first line platinum-based doublet chemotherapy. Hepatotoxicity was graded according to the Common Terminology Criteria for Adverse Events (CTCAE), version 4.0. Risk factors for hepatotoxicity were assessed using logistic regression analysis. Differences in hepatotoxicity between pemetrexed and non-pemetrexed regimens were evaluated after propensity score matching. After accounting for hepatic dysfunction during the first-line treatment, 892 patients receiving beyond first-line treatment were included in the subsequent analyses. Hepatotoxicity in beyond first-line treatment was compared between patients having epidermal growth factor receptor-tyrosine kinase inhibitors (EGFR-TKIs) and chemotherapy alone. In the first-line analysis, 316 (15.0%) patients developed liver dysfunction. Younger age (Odds Ratio [OR] 2.398, 95% Confidence Interval [95% CI] 1.755-3.275), pretreatment liver impairment (OR 2.285, 95% CI 1.622-3.220), and pemetrexed-contained chemotherapy (OR 1.835, 95% CI 1.408-2.393) were risk factors of hepatotoxicity (all P<0.001). Significant differences were observed for patients with all grades of hepatotoxicity while no differences were found concerning grade ¾ hepatotoxicity between 844 pemetrexed and 844 non-pemetrexed regimen matched cases (P<0.0001 and P=0.4220, respectively). After first-line treatment, the presence of hepatitis virus (OR 2.905, 95% CI 1.487-5.675; P=0.002) and TKI therapy (OR 2.621, 95% CI 1.809-3.798; P<0.001) were additionally associated with increased hepatotoxicity. Patients with advanced lung adenocarcinoma with younger age, pretreatment liver injury, and presence of hepatitis virus were at high risk for hepatotoxicity following chemotherapy. Pemetrexed-contained chemotherapy and TKIs should be used cautiously in patients who are susceptible to liver damage.

The Efficacy and Toxicity of Gefitinib in Treating Non-small Cell Lung Cancer: A Meta-analysis of 19 Randomized Clinical Trials

Background: This meta-analysis evaluated the efficacy and toxicity of gefitinib with other commonly used drugs in different treatment settings and epidermal growth factor receptor (EGFR) mutation status.

Methods: Nineteen randomize clinical trials (RCTs) of 6,554 patients with NSCLC were pooled in this meta-analysis by random-effects or fixed-effects model, whichever is proper.

Results: In first-line therapy, gefitinib showed higher odds than chemotherapy (OR = 2.19, 95% CI: 1.20-4.01), but less than other targeted therapies (OR = 0.58, 95% CI: 0.38-0.88). As non-first-line therapy, the overall survival (OS) and progression-free survival (PFS) were similar between gefitinib and controls (HR = 1.00, 95% CI: 0.93-1.08; HR = 0.91, 95% CI: 0.72-1.15), respectively. With the regard to toxicity, the incidences of dry skin, rash and pruritus were higher in gefitinib compared with controls, while gefitinib significantly reduced the incidence of hematologic toxicity.

Conclusion: Gefitinib might be more efficient than chemotherapy, but less efficient than other targeted therapies in ORR, especially in EGFR mutation-positive patients. Gefitinib can decrease the odds of hematologic toxicity compared to controls. Future studies, especially those with EGFR mutation-positive patients, will be needed to confirm our findings.

Making progress in epidermal growth factor receptor (EGFR)-mutant non-small cell lung cancer by surpassing resistance: third-generation EGFR tyrosine kinase inhibitors (EGFR-TKIs)

Epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs) represent the standard of care for advanced non-small cell lung cancer (NSCLC) patients whose tumours harbor an activating EGFR mutation. Unfortunately, resistance to first- and second-generation EGFR-TKIs inevitably occurs in all patients with EGFR-mutant disease approximately within a year of treatment. At least half of these cases are attributed to the emergence of a secondary mutation in exon 20 of the EGFR gene, namely the T790M mutation. Third-generation EGFR-TKIs, including osimertinib and rociletinib, target this epigenic mutation, thus re-sensitizing cancer cells to EGFR-TKI inhibition. Osimertinib to date represents the standard of care in EGFR-mutant tumors after failure of first-line EGFR-TKIs by over-performing platinum-based chemotherapy in the recently reported AURA-3 randomized phase III clinical trial. The aim of this review is to describe the different treatment strategies that have been developed to reverse resistance to first- and second-line EGFR-TKIs, the corresponding mechanisms of resistance and the development of novel-generation EGFR-TKIs. We also discuss the challenge posed by the implementation of third-generation EGFR-TKIs earlier in the course of the disease in first-line treatment of EGFR-mutant NSCLC.

Characteristics of progression to tyrosine kinase inhibitors predict overall survival in patients with advanced non-small cell lung cancer harboring an EGFR mutation

Background

Non-small cell lung cancer (NSCLC) harboring EGFR-sensitizing mutations has a distinct biology and heterogeneous clinical behavior. We evaluated the characteristics to progression such as clinical patterns of progression (dramatic, gradual, and local) with the prognosis of NSCLC patients treated with tyrosine kinase inhibitors (TKIs).

Methods

We reviewed 123 advanced-NSCLC patients with an EGFR-sensitizing mutation treated with TKIs (gefitinib, erlotinib and afatinib). We assessed patients according to clinical factors and progression pattern to TKIs at three centers.

Results

For all patients, 58.5%, 31.7% and 9.8% harbored exon19 deletion, exon21 L858R mutation and other-sensitivity mutations, respectively. Median progression-free survival (PFS) was 8.8 months (95% CI: 7.9-9.7). Sixty percent of patients were asymptomatic. Dramatic-progression was the most frequent pattern (50.4%), followed by gradual-progression (32.5%), and local-progression (17.1%). Median overall survival (OS) was 23.1 months (95% CI: 17.4-28.9). In the univariate analysis, factors associated to a longer OS included pattern [gradual-progression (32.1), dramatic (19.5) and local (18.8 months), P=0.008], and the time to progression to TKI [>12 months (38.5), 6-12 months (19.1), <6 months (9.6), P<0.001]. Multivariate analysis showed that only time to progression to TKI was independently associated to OS and PFS.

Conclusions

Factors at TKI progression associated to a longer OS can define a subset of patients who may benefit from continued TKI therapy, as well as from local-ablative therapy in progression sites, especially in patients without T790M or who lack access to third-generation TKI.

Cost effectiveness analysis of afatinib versus pemetrexed-cisplatin for first-line treatment of locally advanced or metastatic EGFR mutation positive non-small-cell lung cancer from the Singapore healthcare payer's perspective

Background

Non-small-cell lung cancer (NSCLC) accounts for 85% of all lung cancers and is associated with a poor prognosis. Afatinib is an irreversible ErbB family blocker recommended in clinical guidelines as a first-line treatment for NSCLC which harbours an epidermal growth factor receptor (EGFR) mutation. The objective of this study was to evaluate the cost-effectiveness of afatinib versus pemetrexed-cisplatin for first-line treatment of locally advanced or metastatic EGFR mutation positive NSCLC in Singapore.

Methods

A partitioned survival model with three health states (progression-free, progressive disease and death) was developed from a healthcare payer perspective. Survival curves from the LUX-Lung 3 trial (afatinib versus pemetrexed-cisplatin chemotherapy) were extrapolated beyond the trial period to estimate the underlying progression-free survival and overall survival parametric distributions. Rates of adverse reactions were also estimated from LUX-Lung 3 while health utilities from overseas were derived from the literature in the absence of local estimates. Direct costs were sourced from public healthcare institutions in Singapore. Incremental cost-effectiveness ratios (ICERs) were calculated over a 5 year time horizon. Deterministic and probabilistic sensitivity analyses and additional scenario analyses were conducted to explore the impact of uncertainties and assumptions on the cost-effectiveness results.

Results

In the base-case analysis, the ICER for afatinib versus pemetrexed-cisplatin was SG$137,648 per quality-adjusted life year (QALY) gained and SG$109,172 per life-year gained. One-way sensitivity analysis showed the ICER was most sensitive to variations in the utility values, the cost of afatinib and time horizon. Scenario analyses showed that even reducing the cost of afatinib by 50% led to a high ICER which was unlikely to represent a cost-effective use of healthcare resources.

Conclusions

Compared with pemetrexed-cisplatin, afatinib is not cost-effective as a first-line treatment for advanced EGFR mutation-positive NSCLC in Singapore. The findings from our study will be useful to inform local healthcare decision-making and resource allocations for NSCLC treatments, together with other considerations such as clinical effectiveness, safety and affordability of TKIs.

Efatutazone and T0901317 exert synergistically therapeutic effects in acquired gefitinib-resistant lung adenocarcinoma cells

The development of acquired EGFR‐TKI therapeutic resistance is still a serious clinical problem in the management of lung adenocarcinoma. Peroxisome proliferator activated receptor gamma (PPARγ) agonists may exhibit anti‐tumor activity by transactivating genes which are closely associated with cell proliferation, apoptosis, and differentiation. However, it remains not clear whether efatutazone has similar roles in lung adenocarcinoma cells of gefitinib resistant such as HCC827‐GR and PC9‐GR. It has been demonstrated by us that efatutazone prominently increased the mRNA and protein expression of PPARγ, liver X receptor alpha (LXRα),as well as ATP binding cassette subfamily A member 1 (ABCA1). In the presence of GW9662 (a specific antagonist of PPARγ) or GGPP (a specific antagonist of LXRα), efatutazone (40 μmol/L) restored the proliferation of both HCC827‐GR and PC9‐GR cells and obviously inhibited the increased protein and mRNA expression of PPAR‐gamma, LXR‐alpha, and ABCA1 induced by efatutazone. LXRα knockdown by siRNA (si‐LXRα) significantly promoted the HCC827‐GR and PC9‐GR cells proliferation, whereas incubation efatutazone with si‐LXRα restored the proliferation ability compared with the control group. In addition, combination of efatutazone and LXRα agonist T0901317 showed a synergistic therapeutic effect on lung adenocarcinoma cell proliferation and PPAR gamma, LXR A and ABCA1 protein expression. These results indicate that efatutazone could inhibit the cells proliferation of HCC827‐GR and PC9‐GR through PPARγ/LXRα/ABCA1 pathway, and synergistic therapeutic effect is achieved when combined with T0901317.

Adverse kidney effects of epidermal growth factor receptor inhibitors

The epidermal growth factor receptor (EGFR) is implicated in various malignancies. The past decade has seen the development and widespread use of EGFR inhibitors for the successful treatment of such cancers. Available EGFR inhibitors include small molecule tyrosine-kinase inhibitors and monoclonal antibodies. Class-related renal adverse events result in dual toxicity including tubular/electrolyte disorders and glomerulopathies. Tubular injury is common and mainly due to monoclonal antibodies while glomerulopathy is rare and related to various anti-EGFR agents. The exact pathogenesis of anti-EGFR agents associated with kidney disorders remains to be elucidated.

A New Approach to Predict Progression-free Survival in Stage IV EGFR-mutant NSCLC Patients with EGFR-TKI Therapy

Purpose: We established a CT-derived approach to achieve accurate progression-free survival (PFS) prediction to EGFR tyrosine kinase inhibitors (TKI) therapy in multicenter, stage IV EGFR-mutated non-small cell lung cancer (NSCLC) patients.Experimental Design: A total of 1,032 CT-based phenotypic characteristics were extracted according to the intensity, shape, and texture of NSCLC pretherapy images. On the basis of these CT features extracted from 117 stage IV EGFR-mutant NSCLC patients, a CT-based phenotypic signature was proposed using a Cox regression model with LASSO penalty for the survival risk stratification of EGFR-TKI therapy. The signature was validated using two independent cohorts (101 and 96 patients, respectively). The benefit of EGFR-TKIs in stratified patients was then compared with another stage-IV EGFR-mutant NSCLC cohort only treated with standard chemotherapy (56 patients). Furthermore, an individualized prediction model incorporating the phenotypic signature and clinicopathologic risk characteristics was proposed for PFS prediction, and also validated by multicenter cohorts.Results: The signature consisted of 12 CT features demonstrated good accuracy for discriminating patients with rapid and slow progression to EGFR-TKI therapy in three cohorts (HR: 3.61, 3.77, and 3.67, respectively). Rapid progression patients received EGFR TKIs did not show significant difference with patients underwent chemotherapy for progression-free survival benefit (P = 0.682). Decision curve analysis revealed that the proposed model significantly improved the clinical benefit compared with the clinicopathologic-based characteristics model (P < 0.0001).Conclusions: The proposed CT-based predictive strategy can achieve individualized prediction of PFS probability to EGFR-TKI therapy in NSCLCs, which holds promise of improving the pretherapy personalized management of TKIs. Clin Cancer Res; 24(15); 3583-92. ©2018 AACR.

Construction of diagnosis system and gene regulatory networks based on microarray analysis

A microarray analysis generally contains expression data of thousands of genes, but most of them are irrelevant to the disease of interest, making analyzing the genes concerning specific diseases complicated. Therefore, filtering out a few essential genes as well as their regulatory networks is critical, and a disease can be easily diagnosed just depending on the expression profiles of a few critical genes. In this study, a target gene screening (TGS) system, which is a microarray-based information system that integrates F-statistics, pattern recognition matching, a two-layer K-means classifier, a Parameter Detection Genetic Algorithm (PDGA), a genetic-based gene selector (GBG selector) and the association rule, was developed to screen out a small subset of genes that can discriminate malignant stages of cancers. During the first stage, F-statistic, pattern recognition matching, and a two-layer K-means classifier were applied in the system to filter out the 20 critical genes most relevant to ovarian cancer from 9600 genes, and the PDGA was used to decide the fittest values of the parameters for these critical genes. Among the 20 critical genes, 15 are associated with cancer progression. In the second stage, we further employed a GBG selector and the association rule to screen out seven target gene sets, each with only four to six genes, and each of which can precisely identify the malignancy stage of ovarian cancer based on their expression profiles. We further deduced the gene regulatory networks of the 20 critical genes by applying the Pearson correlation coefficient to evaluate the correlationship between the expression of each gene at the same stages and at different stages. Correlationships between gene pairs were calculated, and then, three regulatory networks were deduced. Their correlationships were further confirmed by the Ingenuity pathway analysis. The prognostic significances of the genes identified via regulatory networks were examined using online tools, and most represented biomarker candidates. In summary, our proposed system provides a new strategy to identify critical genes or biomarkers, as well as their regulatory networks, from microarray data.

Prediction of sensitivity to gefitinib/erlotinib for EGFR mutations in NSCLC based on structural interaction fingerprints and multilinear principal component analysis

Background

Non-small cell lung cancer (NSCLC) with activating EGFR mutations, especially exon 19 deletions and the L858R point mutation, is particularly responsive to gefitinib and erlotinib. However, the sensitivity varies for less common and rare EGFR mutations. There are various explanations for the low sensitivity of EGFR exon 20 insertions and the exon 20 T790 M point mutation to gefitinib/erlotinib. However, few studies discuss, from a structural perspective, why less common mutations, like G719X and L861Q, have moderate sensitivity to gefitinib/erlotinib.

Results

To decode the drug sensitivity/selectivity of EGFR mutants, it is important to analyze the interaction between EGFR mutants and EGFR inhibitors. In this paper, the 30 most common EGFR mutants were selected and the technique of protein-ligand interaction fingerprint (IFP) was applied to analyze and compare the binding modes of EGFR mutant-gefitinib/erlotinib complexes. Molecular dynamics simulations were employed to obtain the dynamic trajectory and a matrix of IFPs for each EGFR mutant-inhibitor complex. Multilinear Principal Component Analysis (MPCA) was applied for dimensionality reduction and feature selection. The selected features were further analyzed for use as a drug sensitivity predictor. The results showed that the accuracy of prediction of drug sensitivity was very high for both gefitinib and erlotinib. Targeted Projection Pursuit (TPP) was used to show that the data points can be easily separated based on their sensitivities to gefetinib/erlotinib.

Conclusions

We can conclude that the IFP features of EGFR mutant-TKI complexes and the MPCA-based tensor object feature extraction are useful to predict the drug sensitivity of EGFR mutants. The findings provide new insights for studying and predicting drug resistance/sensitivity of EGFR mutations in NSCLC and can be beneficial to the design of future targeted therapies and innovative drug discovery.

Electronic supplementary material

The online version of this article (10.1186/s12859-018-2093-6) contains supplementary material, which is available to authorized users.

Afatinib in heavily pretreated advanced NSCLC patients who progressed following prior gefitinib or erlotinib: Compassionate use program in Korea

INTRODUCTION

Afatinib, an irreversible ErbB family blocker, approved for first-line treatment of epidermal growth factor receptor (EGFR) mutated advanced non-small cell lung cancer (NSCLC). This study investigated experience of afatinib within a compassionate use program (CUP).

METHODS

The afatinib CUP was an open-label, multicenter, single-arm program in Korea. We enrolled patients with stage IV NSCLC and who had received at least one line of previous cytotoxic chemotherapy and previous EGFR TKI treatment with either an EGFR mutation or documented clinical benefit. The starting dose of afatinib was 50 mg once daily.

RESULTS

From August 2011 to September 2014, 332 patients received at least one dose of afatinib. Most patients were registered in the CUP for fourth- or fifth-line treatment with afatinib. Adverse events (AEs) occurred in 98.1% of patients, including 29.8% with serious AEs. The most common AEs (all grades) were diarrhea (90.1%) and skin rash (62.0%). Dose reductions occurred in 60.5% of patients and discontinuations due to AEs were reported in 11.1% of patients. The response rate and median time to treatment failure (TTF) were 27.4% and 3.3 months (CI 95%, 2.8-3.8 months), respectively, in this highly pretreated population. In subgroup analysis, ECOG PS 0 or 1 and immediate pretreatment with pemetrexed monotherapy or a platinum doublet were associated with a longer TTF for afatinib.

CONCLUSIONS

No additional or unexpected safety concerns were observed, and afatinib demonstrated moderate antitumor activity in advanced NSCLC patients with acquired resistance to gefitinib or erlotinib in a real-world setting.

Concurrent gene alterations with EGFR mutation and treatment efficacy of EGFR-TKIs in Chinese patients with non-small cell lung cancer

PURPOSE

We investigated the frequency of concurrent genes in EGFR-mutant non-small cell lung cancer patients and determined its value in predicting the efficacy of EGFR-TKIs treatment.

METHODS

Three hundred and twenty patients, who harbored EGFR activating mutations and received EGFR-TKIs treatment, were examined for another eight genes including KRAS, NRAS, PIK3CA, BRAF, and HER2 mutations and ALK, ROS1, and RET fusion genes based on reverse transcription PCR. Progression-free survival and overall survival with EGFR-TKIs treatment were evaluated using Kaplan-Meier methods and compared between different patients using log-rank tests.

RESULTS

Twenty-one (6.6%) of 320 EGFR mutant samples with additional gene alterations were identified. The most common concurrent gene was PIK3CA mutation (n = 9), followed by EML4-ALK rearrangement (n = 6), HER2 mutation (n = 3), RET rearrangement (n = 1), ROS1 rearrangement (n = 1) and KRAS mutation (n = 1). Patients with single EGFR mutation had a significantly longer progression-free survival than those with concurrent genes (10.9 vs. 6.0 months, P = 0.002). Among the 21 cases, patients with PIK3CA mutation had the longest median progression-free survival (7.6 months), followed by ALK rearrangement (5.0 months) and other gene types (1.2 months). No overall survival difference was found between patients with single EGFR mutation and concurrent gene alterations (21.0 vs.17.6 months, P = 0.17).

CONCLUSION

We demonstrated that concurrent gene alterations occurred in some patients with EGFR mutations. Concurrent gene alterations decreased the efficacy of EGFR-TKIs.

Early radiological response as predictor of overall survival in non-small cell lung cancer (NSCLC) patients with epidermal growth factor receptor mutations

Background

Epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKI) are the standard treatment of advanced, EGFR-mutant non-small-cell lung cancer (NSCLC). Usually, radiographic assessment of response to chemotherapy is performed after the patient completes the second course of treatment. The optimal timing of response evaluation for patients receiving EGFR-TKIs is, however, not well-defined. The purpose of this study is to evaluate the association of an early radiological response (ERR) to TKIs by computed tomography (CT) with progression-free survival (PFS) and overall survival (OS) in advanced NSCLC patients with EGFR mutations.

Methods

EGFR mutation status was analyzed retrospectively in a cohort of 360 NSCLC patients' between January 2009 and November 2014. Forty of them received treatment with TKI and therefore were included in the study. Response to TKI therapy was defined according to Response Evaluation Criteria in Solid Tumors (RECIST) v1.1. ERR was defined as complete response (CR) or partial response (PR) at the first radiographic evaluation performed within 6-8 weeks after the beginning of the treatment.

Results

Activating mutations in the tyrosine kinase domain of the EGFR gene were mainly exon 19 deletions. Thirty patients (75%) had ERR, 4 of those patients (10%) showed a PR on early CT achieving a CR in the long-term monitoring. Median PFS was longer in patients experiencing an ERR (10.9 vs. 2.4 months; HR: 0.42; 95% CI: 0.19-0.93; P=0.033) than those that did not [stable disease (SD) or progressive disease (PD)]. Median overall survival OS was also significantly increased in patients experiencing ERR (23.2 vs. 11.9 months; HR: 0.3; 95% CI: 0.15-0.85; P=0.021).

Conclusions

ERR in patients treated with EGFR TKI therapy is associated with statistically significant PFS and OS, and could be a surrogate marker of efficacy in these patients. Moreover, ERR provides an early identification of patients not benefitting from TKI, despite the presence of activating EGFR mutations in which further efforts are needed to improve their prognosis.

The impact of EGFR mutations on the incidence and survival of stages I to III NSCLC patients with subsequent brain metastasis

Previous studies have demonstrated the association between EGFR mutations and distant metastasis. However, the association for subsequent brain metastasis (BM) in stages I-III non-small cell lung cancer (NSCLC) patients remains inconclusive. We conducted a retrospective analysis to clarify the impact of EGFR mutations on the incidence of BM and associated survival in patients with stage I-III NSCLC. A total of 491 patients screened for EGFR mutations were retrospectively enrolled. Brain MRI or CT was used to detect the BM. Cumulative incidence of subsequent BM and overall survival (OS) after diagnosis of BM were estimated by the Kaplan-Meier method and compared using log-rank test. We performed Cox proportional hazard regression for predictors of subsequent BM and determinants of OS after BM. The cumulative incidence of BM seemed higher in patients harboring EGFR mutations than those without EGFR mutations although it did not reach statistical significance (hazard ratio [HR] = 1.75, 95% confidence interval [CI] = 0.73~1.81). After adjusting possible confounders, including age, smoking, stage, and tumor size, EGFR mutation became one of the predictors for subsequent BM (HR = 1.89, 95% CI = 1.12~3.17, p = 0.017). Though there was no statistical difference in survival after BM between patients with EGFR mutations and wild-type EGFR (median survival: 17.8 vs. 12.2 months, HR = 0.79, 95% CI = 0.45–1.40), patients with EGFR 19 deletion (Del) tended to have a longer survival after BM than the non-EGFR 19 Del group (median survival: 29.4 vs. 14.3 months, HR 0.58, 95% CI = 0.32–1.09, p = 0.089). In conclusion, our data suggested EGFR mutation to be one of the predictors for subsequent BM in stage I-III patients. Given the small sample size, more studies are warranted to corroborate our results.

The prevalence of EGFR mutation in patients with non-small cell lung cancer: a systematic review and meta-analysis

OBJECTIVES

Estimate the epidermal growth factor receptor (EGFR) mutation prevalence in all non-small cell lung cancer (NSCLC) patients and patient subgroups.

RESULTS

A total of 456 studies were included, reporting 30,466 patients with EGFR mutation among 115,815 NSCLC patients. The overall pooled prevalence for EGFR mutations was 32.3% (95% CI 30.9% to 33.7%), ranging from 38.4% (95% CI: 36.5% to 40.3%) in China to 14.1% (95% CI: 12.7% to 15.5%) in Europe. The pooled prevalence of EGFR mutation was higher in females (females vs. males: 43.7% vs. 24.0%; OR: 2.7, 95% CI: 2.5 to 2.9), non-smokers (non-smokers vs. past or current smokers: 49.3% vs. 21.5%; OR: 3.7, 95% CI: 3.4 to 4.0), and patients with adenocarcinoma (adenocarcinoma vs. non-adenocarcinoma: 38.0% vs. 11.7%; OR: 4.1, 95% CI: 3.6 to 4.8).

MATERIALS AND METHODS

PubMed, EMBASE, and the Cochrane Library were searched to June 2013. Eligible studies reported EGFR mutation prevalence and the association with at least one of the following factors: gender, smoking status and histology. Random-effects models were used to pool EGFR mutation prevalence data.

CONCLUSION

This study provides the exact prevalence of EGFR mutations in different countries and NSCLC patient subgroups.

Turning EGFR mutation-positive non-small-cell lung cancer into a chronic disease: optimal sequential therapy with EGFR tyrosine kinase inhibitors

Four epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs), erlotinib, gefitinib, afatinib and osimertinib, are currently available for the management of EGFR mutation-positive non-small-cell lung cancer (NSCLC), with others in development. Although tumors are exquisitely sensitive to these agents, acquired resistance is inevitable. Furthermore, emerging data indicate that first- (erlotinib and gefitinib), second- (afatinib) and third-generation (osimertinib) EGFR TKIs differ in terms of efficacy and tolerability profiles. Therefore, there is a strong imperative to optimize the sequence of TKIs in order to maximize their clinical benefit. Osimertinib has demonstrated striking efficacy as a second-line treatment option in patients with T790M-positive tumors, and also confers efficacy and tolerability advantages over first-generation TKIs in the first-line setting. However, while accrual of T790M is the most predominant mechanism of resistance to erlotinib, gefitinib and afatinib, resistance mechanisms to osimertinib have not been clearly elucidated, meaning that possible therapy options after osimertinib failure are not clear. At present, few data comparing sequential regimens in patients with EGFR mutation-positive NSCLC are available and prospective clinical trials are required. This article reviews the similarities and differences between EGFR TKIs, and discusses key considerations when assessing optimal sequential therapy with these agents for the treatment of EGFR mutation-positive NSCLC.

[Clinical Observation of Gefitinib with Pericardial Perfusion for Advanced Non-small Cell Lung Cancer]

BACKGROUND

Epidermal growth factor receptor (EGFR) mutation non-small cell lung cancer (NSCLC) is an important subtype of lung cancer. The incidence of malignant pericardial effusion (MPCE) in EGFR-mutant NSCLC patients is high. However, there are few researches on the treatmentof this type of patients.

METHODS

We collected data on clinical characteristics and treatment of advanced NSCLC patients who harboring EGFR mutants and MPCE between January 2010 and December 2016. The treatments were divided into three groups: oral gefitinib combined with pericardial perfusion of hydroxycamptotheci (HCPT) group (gefitinib/HCPT); intravenous chemotherapy combined with pericardial perfusion of HCPT group (chemotherapy/HCPT) and gefitinib monotherapy group. And we retrospectively analyzed patients' outcomes in three groups.

RESULTS

In 273 advanced NSCLC patients with EGFR mutations, 29 cases had pericardial effusion, among which 6 patients with small amount of pericardial effusion were excluded, and 23 patients were analyzed. Median pericardium progression free survival (PFS) was 247 days. PFS for gefitinib/HCPT group (460 days) was superior to PFS for chemotherapy/HCPT group (94 days, P=0.008) and gefitinib monotherapy group (131 days, P=0.032). As for the efficacy of primary pulmonary lesions, the efficacy in gefitinib/ HCPT group was superior to chemotherapy/HCPT group [objective response rate (ORR): 33.3% vs 12.5%; disease control rate (DCR): 86.7% vs 62.5%]. There is no difference of ORR and DCR between gefitinib/HCPT group and gefitinib monotherapy group. No obvious adverse reaction was observed in all three groups.

CONCLUSIONS

First-line gefitinib therapy combined with pericardial perfusion of HCPT can improve pericardium PFS for advanced NSCLC patients who harboring EGFR mutants andmalignantpericardial effusion. This finding should be confirmed further through multicenter, prospective clinical trials with large sample size.

Optimized selection of three major EGFR-TKIs in advanced EGFR-positive non-small cell lung cancer: a network meta-analysis

BACKGROUND

To answer which epidermal growth factor receptor-tyrosine kinase inhibitor (EGFR-TKI) is the best choice for advanced non-small cell lung cancer (NSCLC) EGFR mutants.

RESULTS

16 phase III randomized trials involving 2962 advanced NSCLC EGFR mutants were enrolled. Multiple treatment comparisons showed different EGFR-TKIs shared equivalent curative effect in terms of all outcome measures among the overall, chemo-naïve and previously treated patients. Rank probabilities showed that erlotinib and afatinib had potentially better efficacy compared with gefitinib in both of the overall and chemo-naïve patients. Potentially survival benefit of erlotinib was also observed in previously treated patients compared with gefitinib. Additionally, EGFR-TKI showed numerically greater survival benefit in 19 Del compared with chemotherapy, while it was opposite in 21 L858R. Furthermore, afatinib, erlotinib and gefitinib had high, moderate and low risk of rash & diarrhea, respectively, while the occurrence of elevated liver transaminase was more common in gefitinib.

METHODS

Data of objective response rate (ORR), disease control rate (DCR), progression-free survival (PFS), overall survival (OS) and adverse events were extracted from included studies. Efficacy and toxicity of all included treatments were integrated by network meta-analyses.

CONCLUSION

Our study indicated a high efficacy-high toxicity pattern of afatinib, a high efficacy-moderate toxicity pattern of erlotinib and a medium efficacy-moderate toxicity pattern of gefitinib. Recommended EGFR-TKI should be suggested according to patients' tolerability and therapeutic efficacy in clinical practice. Moreover, the treatment for advanced EGFR-positive NSCLC might be different between 19 Del and 21 L858R.

Gefitinib for advanced non-small cell lung cancer

BACKGROUND

The role of gefitinib for the treatment of advanced non-small cell lung cancer (NSCLC) is evolving. We undertook a systematic review to evaluate the available evidence from all randomised trials.

OBJECTIVES

To determine the effectiveness and safety of gefitinib as first-line, second-line or maintenance treatment for advanced NSCLC.

SEARCH METHODS

We performed searches in CENTRAL, MEDLINE and Embase from inception to 17 February 2017. We handsearched relevant conference proceedings, clinical trial registries and references lists of retrieved articles.

SELECTION CRITERIA

We included trials assessing gefitinib, alone or in combination with other treatment, compared to placebo or other treatments in the first- or successive-line treatment of patients with NSCLC, excluding compassionate use.

DATA COLLECTION AND ANALYSIS

We used the standard Cochrane methodology. Two authors independently assessed the search results to select those with sound methodological quality. We carried out all analyses on an intention-to-treat basis. We recorded the following outcome data: overall survival, progression-free survival, toxicity, tumour response and quality of life. We also collected data for the following subgroups: Asian ethnicity and positive epidermal growth factor receptor (EGFR) mutation.

MAIN RESULTS

We included 35 eligible randomised controlled trials (RCTs), which examined 12,089 patients.General populationGefitinib did not statistically improve overall survival when compared with placebo or chemotherapy in either first- or second-line settings. Second-line gefitinib prolonged time to treatment failure (TTF) (hazard ratio (HR) 0.82, 95% confidence interval (CI) 0.75 to 0.90, P < 0.0001) when compared with placebo. Maintenance gefitinib improved progression-free survival (HR 0.70, 95% CI 0.53 to 0.91, P = 0.007) after first-line therapy.Studies in patients of Asian ethnicity or that conducted subgroup analysesSecond-line gefitinib prolonged overall survival over placebo (HR 0.66, 95% CI 0.48 to 0.91, P = 0.01). In the first-line setting, progression-free survival was improved with gefitinib over chemotherapy alone (HR 0.65, 95% CI 0.43 to 0.98, P = 0.04, moderate quality of evidence). Gefitinib given in combination with a chemotherapy regimen improved progression-free survival versus either gefitinib alone or chemotherapy alone (HR 0.69, 95% CI 0.49 to 0.96, P = 0.03; HR 0.69, 95% CI 0.62 to 0.77, P < 0.00001, respectively). In the second-line setting, progression-free survival was superior in patients given gefitinib over placebo or chemotherapy (HR 0.69, 95% CI 0.52 to 0.91, P = 0.009; HR 0.71, 95% CI 0.57 to 0.88, P = 0.002; moderate quality of evidence, respectively). Combining gefitinib with chemotherapy in the second-line setting was superior to gefitinib alone (HR 0.65, 95% CI 0.43 to 0.97, P = 0.04). As maintenance therapy, gefitinib improved progression-free survival when compared with placebo (HR 0.42, 95% CI 0.33 to 0.54, P < 0.00001).Patients with EGFR mutation-positive tumoursStudies in patients with EGFR mutation-positive tumours showed an improvement in progression-free survival in favour of gefitinib over first-line and second-line chemotherapy (HR 0.47, 95% CI 0.36 to 0.61, P < 0.00001; HR 0.24, 95% CI 0.12 to 0.47, P < 0.0001, respectively). Gefitinib as maintenance therapy following chemotherapy improved overall and progression-free survival (HR 0.39, 95% CI 0.15 to 0.98, P = 0.05; HR 0.17, 95% CI 0.07 to 0.41, P < 0.0001, respectively) in one phase III study when compared to placebo.Toxicities from gefitinib included skin rash, diarrhoea and liver transaminase derangements. Toxicities from chemotherapy included anaemia, neutropenia and neurotoxicity.In terms of quality of life, gefitinib improved Functional Assessment of Cancer Therapy-Lung (FACT-L) (standardised mean difference (SMD) 10.50, 95% CI 9.55 to 11.45, P < 0.000001), lung cancer subscale (SMD 3.63, 95% CI 3.08 to 4.19, P < 0.00001) and Trial Outcome Index (SMD 9.87, 95% CI 1.26 to 18.48, P < 0.00001) scores when compared with chemotherapy.

AUTHORS' CONCLUSIONS

This systematic review shows that gefitinib, when compared with standard first- or second-line chemotherapy or maintenance therapy, probably has a beneficial effect on progression-free survival and quality of life in selected patient populations, particularly those with tumours bearing sensitising EGFR mutations.Patients with EGFR mutations lived longer when given maintenance gefitinib than those given placebo.One study conducted subgroup analysis and showed that gefitinib improved overall survival over placebo in the second-line setting in patients of Asian ethnicity. All other studies did not detect any benefit on overall survival. The data analysed in this review were very heterogenous. We were limited in the amount of data that could be pooled, largely due to variations in study design. The risk of bias in most studies was moderate, with some studies not adequately addressing potential selection, attrition and reporting bias. This heterogeneity may have an impact on the applicability of the resultsCombining gefitinib with chemotherapy appears to be superior in improving progression-free survival to either gefitinib or chemotherapy alone, however further data and phase III studies in these settings are required.Gefitinib has a favourable toxicity profile when compared with current chemotherapy regimens. Although there is no improvement in overall survival, gefitinib compares favourably with cytotoxic chemotherapy in patients with EGFR mutations with a prolongation of progression-free survival and a lesser side effect profile.

Octogenarians with EGFR-mutated non-small cell lung cancer treated by tyrosine-kinase inhibitor: a multicentric real-world study assessing tolerance and efficacy (OCTOMUT study)

Objective

To assess efficacy and tolerance of EGFR tyrosine-kinase inhibitors (TKIs) for advanced EGFR-mutated non-small cell lung cancer (NSCLC) in octogenarians.

Patients and methods

Patients aged 80 years or older with EGFR-mutated NSCLC treated by EGFR TKI between January 2011 and March 2015 whatever the line of treatment were retrospectively selected.

Results

20 centers retrospectively included 114 patients (women, 77.2%; Caucasians, 98.3%; mean age, 83.9 years). A performance status of 0-1 or 2-3 at diagnosis was reported for 71.6% and 28.4% of patients, respectively. Overall, 95.6% of patients had adenocarcinomas and histological stage at diagnosis was stage IV for 79.8% of patients. EGFR mutations were identified mainly on exon 19 (46.5%) and exon 21 (40.4%). A geriatric assessment was performed in 35.1% of patients. TKI treatment was administered to 97.3% of patients as first or second line of treatment. Overall response rate and disease control rate were 63.3% (69/109) and 78.9% (86/109), respectively. Median progression-free survival was 11.9 months (95% confidence interval [CI], 8.6-14.7) and median overall survival was 20.9 months (95% CI, 14.3-27.1). After progression, 36/95 (37.9%) patients received a new line of chemotherapy. Main toxicities were cutaneous for 66.7% of patients (grade 3-4, 10%), diarrhea for 56.0% (grade 3-4, 15%; grade 5, 2%) and others for 25.7% (grade 3-4, 41%).

Conclusions

Octogenarians with EGFR-mutated NSCLC treated by EGFR TKI had clinical outcomes and toxicity profile comparable to younger patients. Geriatric assessment appeared to be underused in this population.

Gefitinib

Gefitinib is an orally active selective inhibitor epidermal growth factor receptor (EGFR). The large randomised phase III IPASS study (gefitinib 250 mg, daily vs carboplatin and paclitaxel) showed a beneficial effect on progression-free survival (PFS) and quality of life in selected patient populations under the treatment with gefitinib (HR for TKI 0.74; 95% CI: 0.65-0.85). In the subgroup of patients with EGFR mutation the effect of gefitinib on PFS was notably, PFS HR 0.48; 95% CI: 0.36-0.64, p < 0.001) and the objective response rate (RR) was 71.2% with gefitinib versus 47.3% with chemotherapy. However no significant difference of overall survival was found. Based on this study gefitinib was approved for the first-line treatment of the patients with non-small cell lung cancer (NSCLC) with sensitising EGFR mutations (exon 19 deletion or L858R point mutation). Gefitinib is metabolized in the liver. Most of the adverse effects of gefitinib, such as rash, dry skin and diarrhoe, are mild to moderate in severity and are reversible.

The impact of intermittent versus continuous exposure to EGFR tyrosine kinase inhibitor on selection of EGFR T790M-mutant drug-resistant clones in a lung cancer cell line carrying activating EGFR mutation

Drug-resistant cell lines are essential tools for investigating the mechanisms of resistance to molecular-targeted anti-cancer drugs. However, little is known about how to establish clinically relevant drug-resistant cell lines. Our study examined the impact of a drug-free period on the establishment of a cell line with clinically relevant resistance to molecular-targeted drugs. We used PC9 cells, a lung cancer cell line carrying EGFR mutation, because this is a validated target for EGFR tyrosine kinase inhibitors (TKI). PC9 cells were intermittently or continuously exposed to increasing concentrations of gefitinib (0.01 μM to 1.0 μM) and the emergence of the most common acquired resistance mutation in EGFR, T790M, was determined. T790M was detected at a 25-fold lower drug concentration in cells continuously exposed to gefitinib (PC9/GRc) than in cells intermittently exposed to gefitinib (PC9/GRi) (0.04 μM vs 1.0 μM, respectively). The mutation frequencies at those drug concentrations were 19.8% and 8.0% in PC9/GRc and PC9/GRi cells, respectively. After drug-free culture for 8 weeks, resistance to gefitinib decreased in the PC9/GRi cells but not in the PC9/GRc cells. In the PC9/GRc cells, the frequency of the T790M mutation was consistently about 20% from 0.04 μM to 1.0 μM of gefitinib. In the PC9/GRc cells, the T790M mutation was detected in all single-cell clones, at frequencies ranging from 7.0% to 37.0%, with a median of 19.5% (95% confidence interval, 17.3%–20.9%). In conclusion, compared with intermittent drug exposure, continuous exposure might select better minor drug-resistant clones when creating cell lines resistant to molecular-targeted drugs.

Comparative outcome assessment of epidermal growth factor receptor tyrosine kinase inhibitors for the treatment of advanced non-small-cell lung cancer: a network meta-analysis

Introduction

Tyrosine kinase inhibition of the epidermal growth factor receptor (EGFR) is the standard in the first line treatment of patients with advanced non-small–cell lung cancer (NSCLC) harbouring EGFR activating mutations. Here we aim to discern efficacy and toxicity measures through a meta-analysis of published studies that could aid treatment selection.

Materials And Methods

We performed a meta-analysis of the main randomized clinical trials evaluating the currently approved EGFR-TKIs in first-line of treatment of EGFR-positive advanced NSCLC. Cochrane guidelines were used for statistical analysis.

Results

3,179 patients were included. All EGFR TKIs showed improved outcomes with respect to ORR and PFS when compared to standard platinum-doublet chemotherapy. Comparative ORR for gefitinib, erlotinib and afatinib were 52.1%, 67.3% and 61.6% respectively. HRs for PFS were 0.62 (95% CI, 0.38–1.00) for gefitinib, 0.28 (95% CI, 0.17–0.45) for erlotinib and 0.40 (95% CI, 0.20–0.83) for afatinib. HRs for OS were not statistically significant for any agent.

Conclusions

Our results suggest similar clinical efficacy and higher toxicity of Afatinib treatment. As this still remains the agent with best CSF penetration, we suggest its use is limited to patients presenting with brain metastasis. We suggest the use of Gefitinib in patients without CNS involvement. Faced with the impossibility to dose-reduce Gefitinib, Erlotinib represents a tolerable and effective alternative to Afatinib and Gefitinib if response to EGFR inhibition is considered still effective.

[Current Status and Progress in Molecular Imaging of Non-small Cell Lung Cancer for Molecular Targeted EGFR-TKI Treatment Sensitivity and Treatment Tolerance Prediction]

肺癌80%以上为非小细胞肺癌（non-small cell lung cancer, NSCLC），表皮生长因子受体（epidermal growth factor receptor, EGFR）介导的信号通路与NSCLC发生发展密切相关。针对EGFR的小分子EGFR赖氨酸激酶抑制剂（EGFR-tyrosine kinase inhibitor, EGFR-TKI）被应用于NSCLC的临床治疗，正电子发射计算机断层显像（positron emission tomography/computed tomgraphy, PET/CT）能够无创地对NSCLC患者全身EGFR表达及突变状况进行连续动态监测。¹⁸F-FDG PET/CT显像对于EGFR活化突变、EGFR-TKI治疗疗效具有预测价值，并且能够在体直接观察到药物与全身肿瘤病灶EGFR靶向结合的具体情况，通过治疗前后的PET-CT显像，实现治疗前高敏人群筛选和治疗全过程的动态监测、治疗策略指导，对实现NSCLC的EGFR-TKI精准治疗至关重要。

Survival analysis of patients with advanced non-small cell lung cancer receiving tyrosine kinase inhibitor (TKI) treatment: A multi-center retrospective study

Background

The study was conducted to assess differences in overall survival (OS) in patients with non‐small cell lung cancer (NSCLC) receiving different treatment modalities of tyrosine kinase inhibitors (TKIs).

Methods

A total of 463 NSCLC patients receiving TKI treatment were included. OS was compared according to treatment timing in all patients, the elderly, and patients positive for EGFR mutations.

Results

One hundred and seventy two patients received TKIs as first‐line treatment, 220 as second‐line, and 67 as third‐line. The results between the three groups were not statistically significant: the one, two, and three‐year OS rates were: 55.3%, 22.3%, and 11.3% (first‐line); 59.6%, 27.8%, and 14.9% (second‐line); and 53.8%, 41.3%, and 29.5% (third‐line), respectively (P = 0.095). Results between the three groups of elderly patients were also not statistically significant (P = 0.469). The one and two‐year OS rates in EGFR mutation‐positive patients receiving first‐line treatment were 48% and 17.5%, respectively. The one, two, and three‐year OS rates of patients receiving second‐line treatment were: 54.2%, 30.3%, and 20.2%, respectively. There were no statistically significant differences between the groups with EGFR mutations receiving first‐line or second‐line treatment. Thirteen EGFR mutation‐positive patients received third‐line TKI treatment for a median duration of 7 months. Their one and two‐year OS rates were 69.8% and 58.2%, respectively, which were higher than in the other two groups (P = 0.015).

Conclusion

Three lines of TKI therapy can prolong survival in NSCLC patients. Elderly patients can benefit from TKI therapy. EGFR mutation‐positive patients can benefit from second‐line or third‐line TKI therapy.

Calcein-acetoxymethy ester enhances the antitumor effects of doxorubicin in nonsmall cell lung cancer by regulating the TopBP1/p53RR pathway

Calcein acetoxymethyl ester (calcein-AM) treatment has been reported to exert antitumor effects in certain cancer cells; however, the detailed mechanism of action of calcein-AM in cancers remains unclear, especially in nonsmall cell lung cancer (NSCLC). This study focused on the function and mechanism of action of calcein-AM in NSCLC. We used cell viability assays, western blotting, and EdU proliferation assay combined with calcein-AM treatment or siRNA interference to investigate the role of topoisomerase IIβ binding protein 1 (TopBP1) and p53 in NSCLC chemotherapy. We found that calcein-AM has antitumor effects in lung cancer and enhances the antitumor effects of doxorubicin in NSCLC. Furthermore, we found that TopBP1, which we previously showed was involved in doxorubicin resistance through upregulation of aberrant p53, was involved in calcein-AM-mediated increased doxorubicin sensitivity. Doxorubicin upregulated the expression of aberrant p53. Calcein-AM repressed the expression of TopBP1, which resulted in reduced expression of aberrant p53 and disrupted the antiapoptotic activity mediated by the TopBP1/mutp53 pathway in NSCLC. Together, our findings show that calcein-AM, the cell-permeable derivative of calcein, exerts significant antitumor effects in NSCLC, and can enhance the antitumor effect of doxorubicin by regulating the TopBP1/mutp53 pathway. These findings provide novel insight into lung cancer treatment.

A meta-analysis: Evaluation of safety and efficacy of the epidermal growth factor receptor-tyrosine kinase inhibitor monotherapy versus platinum-based doublets chemotherapy in East Asia

OBJECTIVE

Several clinical trials have shown that advanced nonsmall cell lung cancer (NSCLC) patients can benefit from treatment with epidermal growth factor receptor-tyrosine kinase inhibitor (EGFR-TKI) monotherapy than receiving platinum-based doublets chemotherapy in the first-line treatment of advanced NSCLC; the objective of this study was to evaluate whether patients could be treated with EGFR-TKI for advanced NSCLC in the first-line setting.

PATIENTS AND METHODS

A literature search was conducted on the Cochrane Controlled Trials Register Databases, MEDLINE, EMBASE, Web of Science databases, and Chinese Biomedical Literature Database without exclusion of material published in any language. We performed a meta-analysis of five randomized studies that compared EGFR-TKI with platinum-based doublets chemotherapy for the patients of advanced NSCLC in the first-line setting. The primary end-point was the progression-free survival (PFS) of each treatment arm. The secondary end-points were overall survival (OS), objective response rate (ORR), adverse effects, and quality of life (qol).

RESULTS

Five randomized controlled trials totaling 2080 patients were included in the review. Meta-analysis results are as follows: There were statistically significant differences in overall PFS (hazard ratio [HR] =0.47; 95% confidence interval [CI]: [0.27, 0.83], P = 0.009) and the PFS of the EGFR-M + subgroup (HR = 0.29; 95% CI: [0.17-0.51], P < 0.0001). Compared with patients receiving the platinum-based doublets chemotherapy group, there were no statistically significant differences between the two groups with regard to overall OS (HR = 0.92; 95% CI: [0.80-1.06], P = 0.25).

CONCLUSION

Compared with the platinum-based doublets chemotherapy, EGFR-TKI significantly prolonged PFS, increased ORR, improved qol, not significantly increased the nonhematologic toxicity and at the same time decreased the nonhematologic toxicity but not significantly increased the transaminase toxicity for advanced NSCLC patients in East Asia. Although there is convincing evidence to confirm the results mentioned herein, they still need to be confirmed by large-sample trials.

Clinical management of epidermal growth factor receptor mutation-positive non-small cell lung cancer patients after progression on previous epidermal growth factor receptor tyrosine kinase inhibitors: the necessity of repeated molecular analysis

One of the most important advances in the treatment of non-small cell lung cancer (NSCLC) has been the identification of molecular alterations vulnerable to targeted inhibition, such as mutations in the epidermal growth factor receptor (EGFR) gene. EGFR tyrosine kinase inhibitors (EGFR-TKIs) are targeted agents used to treat EGFR mutation-positive advanced NSCLC showing significant improvements in terms of response rate (RR) and progression-free survival (PFS) compared to conventional chemotherapy. However, all patients eventually develop resistance to first-line EGFR-TKIs. The most common mechanism of acquired resistance is the secondary acquisition of a single missense mutation within exon 20 in the EGFR gene, known as the T790M mutation (49-60%). New agents targeting the T790M mutation have undergone clinical development, and among these, osimertinib has shown significant activity in relapsing EGFR mutation positive patients harbouring the T790M mutation. Although precision medicine is a reality for NSCLC, obtaining relevant tissue for repeated molecular analysis from these patients remains a challenge. In this article, a group of experts from the Spanish Society of Medical Oncology (SEOM) and the Spanish Lung Cancer Group (GECP) evaluated the role of rebiopsy and the potential application of plasma-testing methodologies in advanced EGFR mutation patients progressing after EGFR-TKI.

Targeting RET-driven cancers: lessons from evolving preclinical and clinical landscapes

The gene encoding the receptor-tyrosine kinase RET was first discovered more than three decades ago, and activating RET rearrangements and mutations have since been identified as actionable drivers of oncogenesis. Several multikinase inhibitors with activity against RET have been explored in the clinic, and confirmed responses to targeted therapy with these agents have been observed in patients with RET-rearranged lung cancers or RET-mutant thyroid cancers. Nevertheless, response rates to RET-directed therapy are modest compared with those achieved using targeted therapies matched to other oncogenic drivers of solid tumours, such as sensitizing EGFR or BRAF^V600E mutations, or ALK or ROS1 rearrangements. To date, no RET-directed targeted therapeutic has received regulatory approval for the treatment of molecularly defined populations of patients with RET-mutant or RET-rearranged solid tumours. In this Review, we discuss how emerging data have informed the debate over whether the limited success of multikinase inhibitors with activity against RET can be attributed to the tractability of RET as a drug target or to the lack, until 2017, of highly specific inhibitors of this oncoprotein in the clinic. We emphasize that novel approaches to targeting RET-dependent tumours are necessary to improve the clinical efficacy of single-agent multikinase inhibition and, thus, hasten approvals of RET-directed targeted therapies.

A comprehensive review of uncommon EGFR mutations in patients with non-small cell lung cancer

INTRODUCTION

Patients with non-small cell lung cancer (NSCLC) harboring uncommon epidermal growth factor receptor (EGFR) mutations are a heterogeneous group exhibiting differential responses to EGFR inhibitors. This retrospective study reviews the prevalence of uncommon EGFR mutations in a Chinese NSCLC cohort and the clinical characteristics and efficacy of EGFR tyrosine kinase inhibitors (TKIs) associated with these patients.

MATERIALS ANDMETHODS

A total of 5363 lung cancer patients were screened and underwent EGFR genotyping at the Guangdong Lung Cancer Institute. Of those with uncommon EGFR mutations, the clinical characteristics and responses to EGFR-TKIs were reviewed retrospectively.

RESULTS

Uncommon EGFR mutations were observed in 218 patients, comprising 11.9% of all patients with documented EGFR mutations. More smokers (30.7% vs. 24.3%, P=0.039) and males (54.1% vs. 44.4%, P=0.007) were among the patients with uncommon mutations compared with common mutations. The most frequent uncommon mutations were exon 20 insertions (30.7%, n=67), followed by G719X mutations (21.1%, n=46) and compound L858R mutations (17.0%, n=37). Favorable efficacy was observed in patients harboring compound L858R or G719X mutations, with a median progression-free survival (PFS) of 15.2 (95% CI: 8.7-21.7) or 11.6 (95% CI: 3.6-19.6) months, respectively. The median PFS of those with the T790M mutation or an exon 20 insertion was 1.0 (95% CI: 0.0-2.2) and 3.0 (95% CI: 1.3-4.7) months, respectively.

CONCLUSION

This study reviewed the prevalence of uncommon EGFR mutations and their sensitivity to EGFR-TKIs. Favorable responses were observed in patients with G719X and compound L858R mutations, indicating that they may benefit from EGFR-TKIs as a first-line therapy.

Adverse Prognostic CT Findings for Patients With Advanced Lung Adenocarcinoma Receiving First-Line Epidermal Growth Factor Receptor-Tyrosine Kinase Inhibitor Therapy

OBJECTIVE

The purpose of this study is to investigate adverse prognostic CT findings in patients with advanced-stage lung adenocarcinoma who are receiving epidermal growth factor receptor (EGFR)-tyrosine kinase inhibitor (TKI) therapy as first-line therapy.

MATERIALS AND METHODS

We included 199 patients (71 men and 128 women; mean ± SD age, 64.3 ± 11.2 years) with stage IIIB or IV lung adenocarcinoma who received first-line EGFR-TKI therapy between January 2009 and December 2015. Clinical findings and imaging parameters on CT images obtained before TKI therapy were analyzed, including tumor size, TNM category according to the seventh edition of the American Joint Committee on Cancer lung cancer TNM staging system, tumor type, the presence of cavity or necrosis, pleural effusion, and metastasis to pleura, lung, and distant organs. Response evaluation was performed according to the Response Evaluation Criteria in Solid Tumor version 1.1 guidelines. Correlation of clinical and radiologic findings with durations of progression-free survival (PFS) and overall survival (OS) was evaluated using a Cox proportional hazard model.

RESULTS

Pleural effusion (hazard ratio [HR], 2.095; 95% CI, 1.394-3.147; p < 0.001) and an N2 or N3 tumor category (HR, 2.145; 95% CI, 1.280-3.594; p = 0.004) were significantly associated with a short PFS duration in multivariate analysis. Older age (HR, 1.040; 95% CI, 1.014-1.067; p = 0.002), an N2 or N3 tumor category (HR, 2.427; 95% CI, 1.068-5.518; p = 0.034), pleural effusion (HR, 1.903; 95% CI, 1.105-3.276; p = 0.020), and distant metastasis (HR, 2.795; 95% CI, 1.356-5.765; p = 0.005) were associated with a short OS duration in multivariate analysis.

CONCLUSION

Pre-TKI therapy CT findings of pleural effusion and high N-category tumors are associated with short durations of PFS and OS in patients with lung adenocarcinoma who are receiving EGFR-TKI therapy.

Clinical and molecular characteristics of non-small-cell lung cancer (NSCLC) harboring EGFR mutation: results of the nationwide French Cooperative Thoracic Intergroup (IFCT) program

BACKGROUND

EGFR mutations cause inconsistent response to EGFR tyrosine-kinase inhibitors (TKI). To better understand these features, we reviewed all cases of EGFR-mutated non-small-cell lung cancer collected in the Biomarkers France database.

PATIENTS AND METHODS

Of 17 664 patients, 1837 (11%) with EGFR-mutated non-small-cell lung cancer were retrospectively analyzed for clinical and molecular characteristics. Results were correlated with survival and treatment response for the 848 stage IV patients.

RESULTS

EGFR exon 18, 19, 20 and 21 mutations were found in 102 (5.5%), 931 (51%), 102 (5.5%) and 702 (38%) patients, respectively. Over 50% of exon 18 and 20 mutated patients were smokers. The median follow-up was 51.7 months. EGFR mutation type was prognostic of overall survival (OS) versus wild-type {exon 19: hazard ratio (HR)=0.51 [95% confidence interval (CI): 0.41-0.64], P < 0.0001; exon 21: HR = 0.76 (95% CI: 0.61-0.95), P = 0.002; exon 20: HR = 1.56 (95% CI: 1.02-2.38), P = 0.004}. EGFR mutation type was prognostic of progression-free survival versus wild-type [exon 19: HR = 0.62 (95% CI: 0.49-0.78), P < 0.0001; exon 20: HR = 1.46 (95% CI: 0.96-2.21), P = 0.07]. First-line treatment choice did not influence OS in multivariate analysis. First-line TKI predicted improved progression-free survival versus chemotherapy [HR = 0.67 (95% CI: 0.53-0.85), P = 0.001]. OS was longer for del19 versus L858R, which was associated with better OS compared with other exon 21 mutations, including L861Q. TKI improved survival in patients with exon 18 mutations, while chemotherapy was more beneficial for exon 20-mutated patients.

CONCLUSION

EGFR mutation type can inform the most appropriate treatment. Therapeutic schedule had no impact on OS in our study, although TKI should be prescribed in first-line considering the risk of missing the opportunity to use this treatment.

PPARγ agonist efatutazone and gefitinib synergistically inhibit the proliferation of EGFR-TKI-resistant lung adenocarcinoma cells via the PPARγ/PTEN/Akt pathway

Development of acquired resistance to EGFR-TKI therapy continues to be a serious clinical problem in Lung adenocarcinoma management. Peroxisome proliferator-activated receptor gamma (PPARγ) agonists demonstrate anti-tumor activity likely via transactivating genes that regulate cell proliferation, differentiation and apoptosis. Efatutazone, a novel later generation PPARγ agonist, selectively activates PPARγ target genes and has antiproliferative effects in a range of malignancies. However, the exact function and molecular mechanism of PPARγ agonists efatutazone in EGFR-TKI gefitinib-resistance of Lung adenocarcinoma has not been determined. In this study, we studied the development of acquired resistance to an EGFR-TKI gefitinib in lung adenocarcinoma cells and investigated the antiproliferative effects of efatutazone in the acquired resistant cells. The treatment of gefitinib-resistant cells with efatutazone reduced the growth of gefitinib-resistant cells in a dose- and time-dependent manner, and facilitated the anti-proliferative effects of gefitinib. Mechanistic investigations suggested that efatutazone acted by upregulating protein expression of PPARγ, phosphatase and tensin homolog (PTEN), inactivating the Akt pathway, followed by dephosphorylation of p21Cip1 at Thr145 without affecting the transcriptional levels. Our results suggested that efatutazone, alone or in combination with gefitinib, might offer therapeutic effects in lung adenocarcinoma.