Efficacy of EGFR tyrosine kinase inhibitors for non-adenocarcinoma lung cancer patients harboring EGFR-sensitizing mutations in China

Effectiveness comparison of third-generation EGFR-TKI as initial and sequential therapy in adjuvant treatment for EGFR mutation-sensitive stage IIIA non-small cell lung cancer after surgery

Introduction

Although third-generation epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs) Osimertinib has been approved as adjuvant therapy for resected stage IIIA non-small cell lung cancer (NSCLC) with EGFR-sensitive mutations, the optimal treatment sequencing of EGFR-TKIs, particularly whether Osimertinib should be the initial or sequential therapy following the first-generation EGFR-TKIs remains uncertain.

Methods

A retrospective analysis was conducted on a cohort of patients with EGFR-mutated stage IIIA NSCLC who received treatment with either first-generation EGFR-TKIs or Osimertinib (third-generation) alone, or in sequential combination, at a single institution. The data analysis involved using the Kaplan-Meier method, log-rank test, and Cox regression.

Results

Out of the total 148 patients with stage IIIA NSCLC included in the study, 76 individuals underwent treatment with either first-generation EGFR-TKIs (referred to as subgroup "1″) or exclusively Osimertinib (subgroup "0 + 3″), or a sequential combination of the two (subgroup "1 + 3″) following surgery. Both univariate and multivariate analyses demonstrated that there were no discernible disparities in terms of disease-free survival and overall survival between subgroup " 1″ and " 1 + 3," nor between subgroup " 0 + 3″ and "1 + 3".

Conclusion

The findings from this study indicate that the introduction of third-generation EGFR-TKI Osimertinib did not yield enhanced survival benefits when compared to the first-generation drug in patients with stage IIIA completely resected NSCLC who were administered EGFR-TKIs as part of their postoperative adjuvant treatment. Additionally, within the observed sample size of this cohort, the sequential use of Osimertinib alongside first-generation EGFR-TKI did not demonstrate superiority over using either the first-generation EGFR-TKI or Osimertinib alone in terms of postoperative survival.

A case of epidermal growth factor receptor tyrosine kinase inhibitor effectiveness in epidermal growth factor receptor mutation-positive squamous cell carcinoma

A 71-year-old non-smoker woman was admitted to our hospital because of left front chest pain. A computed tomography scan showed a large mass of >7.0 cm in the lower left part of the lung and multiple organ metastases in the liver, brain, bone, and left adrenal gland. Pathological analysis of a resected specimen obtained by bronchoscopy revealed keratinization. In addition, p40 was positive and thyroid transcription factor-1, synaptophysin, CD56, and chromogranin A were negative by immunohistochemistry. Programmed cell death ligand 1 expression was 1%-10%, and exon 19 deletion was detected. We diagnosed the patient with stage IVB lung squamous cell carcinoma and administered osimertinib. Osimertinib was later replaced with afatinib because of grade 3 skin rash. Overall, the size of the cancer was decreased. Furthermore, her symptoms, laboratory data, and computer tomographic findings markedly improved. In summary, we experienced a case of epidermal growth factor receptor-positive lung squamous cell carcinoma that was responsive to epidermal growth factor receptor tyrosine kinase inhibitors.

Evaluation of Clinical Outcomes of Icotinib in Patients With Clinically Diagnosed Advanced Lung Cancer With EGFR-Sensitizing Variants Assessed by Circulating Tumor DNA Testing: A Phase 2 Nonrandomized Clinical Trial

Importance

The inability to obtain a pathological diagnosis in a certain proportion of patients with clinically diagnosed advanced lung cancer impedes precision treatment in clinical practice.

Objective

To evaluate the clinical outcome of first-line icotinib in patients with clinically diagnosed advanced lung cancer with unknown pathological status and positive epidermal growth factor receptor (EGFR)-sensitizing variants assessed by circulating tumor DNA (ctDNA).

Design, Setting, and Participants

The Efficiency of Icotinib in Plasma ctDNA EGFR Mutation-Positive Patients Diagnosed With Lung Cancer (CHALLENGE) trial is a prospective, multicentered, open-label, single-arm phase 2 nonrandomized clinical trial conducted between July 1, 2017, and July 31, 2019. Patients with systemic treatment-naive, clinically diagnosed advanced peripheral lung cancer, unknown pathological status, and positive pretreatment plasma EGFR-sensitizing variants were eligible. A total of 391 potentially eligible Chinese patients from 19 centers in China were screened for ctDNA EGFR variants by 3 independent detection platforms (Super amplification refractory mutation system [SuperARMS] polymerase chain reaction, droplet digital polymerase chain reaction, and next-generation sequencing), and those with EGFR variants tested by any platform were included. Analyses were conducted from September 9 to December 31, 2021.

Interventions

Enrolled patients were treated with oral icotinib tablets (125 mg 3 times daily) until disease progression, death, or treatment discontinuation due to various reasons, such as toxic effects and withdrawing consent.

Main Outcomes and Measures

The primary end point was objective response rate (ORR). The secondary end points included progression-free survival (PFS), overall survival (OS), disease control rate (DCR), and the concordance among the 3 detection platforms.

Results

Of 116 included patients, 76 (65.5%) were female, and the median (range) age was 64 (37-85) years. The median (IQR) follow-up duration was 36.3 (30.2-40.7) months. The ORR was 52.6% (95% CI, 43.1%-61.9%). The median PFS and OS were 10.3 months (95% CI, 8.3-12.2) and 23.2 months (95% CI, 17.7-28.0), respectively, and the DCR was 84.5% (95% CI, 76.6%-90.5%). The concordance rate among the 3 detection platforms was 80.1% (313 of 391), and the clinical outcomes in patients identified as positive by any platform were comparable.

Conclusions and Relevance

This prospective phase 2 nonrandomized clinical trial suggests that for patients with clinically diagnosed advanced lung cancer with unknown pathological status, ctDNA-based EGFR genotyping could help decision-making in particular clinical situations, while still warranting future larger-scaled real-world exploration.

Trial Registration

ClinicalTrials.gov Identifier: NCT03346811.

EGFR-Mutated Squamous Cell Lung Cancer and Its Association With Outcomes

Background

The therapeutic efficacy of epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs) in advanced EGFR-mutant lung squamous cell carcinoma (SCC) patients remains uncertain. Furthermore, the factors underlying the responsiveness have not been fully investigated. We therefore investigated the link between genomic profiles and EGFR-TKI efficacy.

Material and Methods

We consecutively enrolled stage IV, EGFR-mutant, and EGFR-TKI–treated patients with SCC. Patients with EGFR wild-type lung SCC and EGFR-mutant lung adenocarcinoma were consecutively enrolled as controls, and next-generation sequencing (NGS) was performed.

Results

In total, 28 EGFR-mutant lung SCC, 41 EGFR-mutant lung adenocarcinoma, and 40 EGFR wild-type lung SCC patients were included. Among the patients with EGFR mutations, shorter progression-free survival (PFS) was observed in SCC compared to adenocarcinoma (4.6 vs. 11.0 months, P<0.001). Comparison of the genomic profiles revealed that EGFR-mutant SCC patients had similar mutation characteristics to EGFR-mutant adenocarcinoma patients, but differed from those with EGFR wild-type SCC. Further exploration of EGFR-mutant SCC revealed that mutations in CREBBP (P = 0.005), ZNF217 (P = 0.016), and the Wnt (P = 0.027) pathway were negatively associated with PFS. Mutations in GRM8 (P = 0.025) were associated with improved PFS.

Conclusions

EGFR-mutant lung SCC has a worse prognosis than EGFR-mutant adenocarcinoma. Mutations in other genes, such as CREBBP, ZNF217, GRM8, or Wnt that had implications on PFS raise the possibility of understanding mechanisms of resistance to EGFR-TKI in lung SCC, which will aid identification of potential beneficial subgroups of patients with EGFR-mutant SCCs receiving EGFR-TKIs.

Targeting histone deacetylase enhances the therapeutic effect of Erastin-induced ferroptosis in EGFR-activating mutant lung adenocarcinoma

Background

Intrinsic or acquired resistance to epidermal growth factor receptor-tyrosine kinase inhibitors (EGFR-TKIs) is common, thus strategies for the management of EGFR-TKIs resistance are urgently required. Ferroptosis is a recently discovered form of cell death that has been implicated in tumorigenesis and resistance treatment. Accumulating evidence suggests that ferroptosis can be therapeutically exploited for the treatment of solid tumors; however, whether ferroptosis can be targeted to treat EGFR mutant lung cancer and/or overcome the resistance to EGFR-TKIs is still unknown.

Methods

The effect of ferroptosis inducers on a panel of EGFR mutant lung cancer cell lines, including those with EGFR-TKI intrinsic and acquired (generated by long-term exposure to the third-generation EGFR-TKI osimertinib), was determined using cytotoxicity assays. Further, drug candidates to enhance the effect of ferroptosis inducers were screened through implementing WGCNA (weighted gene co-expression network analysis) and CMAP (connectivity map) analysis. Flow cytometry-based apoptosis and lipid hydroperoxides measurement were used to evaluate the cell fates after treatment.

Results

Compared with EGFR-TKI-sensitive cells, those with intrinsic or acquired resistance to EGFR-TKI display high sensitivity to ferroptosis inducers. In addition, Vorinostat, a clinically used inhibitor targeting histone deacetylase, can robustly enhance the efficacy of ferroptosis inducers, leading to a dramatic increase of hydroperoxides in EGFR mutant lung cancer cells with intrinsic or acquired resistance to EGFR-TKI. Mechanistically, Vorinostat promotes ferroptosis via xCT downregulation.

Conclusions

Ferroptosis-inducing therapy shows promise in EGFR-activating mutant lung cancer cells that display intrinsic or acquired resistance to EGFR-TKI. Histone deacetylase inhibitor (HDACi) Vorinostat can further promote ferroptosis by inhibiting xCT expression.

Key prognostic factors for EGFR-mutated non-adenocarcinoma lung cancer patients in the Japanese Joint Committee of Lung Cancer Registry Database

INTRODUCTION

The efficacy of epidermal growth factor receptor (EGFR)-tyrosine kinase inhibitors (TKIs) for EGFR-mutated non-adenocarcinoma (ADC) non-small cell lung cancer patients is not well established. Herein, we investigated key prognostic factors influencing the efficacy of EGFR-TKIs in these patients.

METHODS

A total of 12,320 lung cancer patients pathologically diagnosed in 2012 at teaching hospitals in Japan were retrospectively selected. The follow-up survey was closed in 2016.

RESULTS

EGFR-mutated non-ADC patients were more prone to malignant pleural effusion (MPE) and distant metastasis than ADC patients (P = 0.071 and 0.022, respectively). EGFR-mutated ADC patients were likely to have a longer median overall survival (OS) than non-ADC patients [hazard ratio (HR) 1.3 (95 % CI, 0.97-1.8, P = 0.072)-29.5 months (95 % CI, 27.9-31.1 months) versus 19.5 months (95 % CI, 10.8-28.2 months) (P = 0.068)]. There was no significant difference in median OS between EGFR-positive ADC and non-ADC patients receiving treatment with first-generation EGFR-TKI. Among EGFR-positive non-ADC patients, the median OS was significantly longer for patients receiving EGFR-TKI treatment than for those who did not [HR 4.5 (95 % CI, 2.1-9.8, P < 0.001)-25.5 months (95 % CI, 8.1-42.9 months) versus 7.5 months (95 % CI, 3.4-11.6 months) (P < 0.001)]. While there was no significant difference in the median OS for ADC patients with either 19 del or L858R mutations, the median OS was significantly longer for EGFR-mutated non-ADC patients with 19 del than for those with L858R mutation (HR 3.2 [95 % CI, 1.5-6.9, P = 0.004]; it was not reached for 19 del and was 15.5 months for L858R [95 % CI, 6.6-24.4 months], P = 0.002).

DISCUSSION

EGFR-mutated non-ADC patients were more prone to MPE and distant metastasis. Both ADC and EGFR del19-positive non-ADC patients can benefit from EGFR-TKI treatment, whereas EGFR L858R-positive non-ADC patients might require different therapeutic options.

Clinical Outcomes of Different Generations of EGFR Tyrosine Kinase Inhibitors in Advanced Lung Adenosquamous Carcinoma

OBJECTIVES

The role of targeted therapy in patients with lung adenosquamous carcinoma (ASC) has been controversial and it was unclear whether a third-generation epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor (TKI) could improve outcomes. This study was designed to evaluate the efficacy of different generations of EGFR TKI therapy in ASC patients with sensitive EGFR mutations.

METHODS

Patients with non-small cell lung cancer (NSCLC) diagnosed at the Shanghai Chest Hospital between January 2010 and December 2016 were retrospectively reviewed.

RESULTS

A total of 10,037 NSCLC patients tested for EGFR mutations were screened, with primary ASC accounting for 1.4% (139/10,037). Positive EGFR mutations were found in 51.1% (71/139) of ASC patients, including 67 sensitive mutations (19del or 21L858R) and four uncommon mutations (19del + 20T790M, 21L858R + 20T790M, 19L747P + 20Q787Q, and 21L861Q). Sensitive EGFR mutations occurred more frequently in younger (62.0 vs 65.0, p = 0.010), non-smoking (83.6% vs 57.8%, p = 0.002) women (56.7% vs 34.4%, p = 0.014). Among the 36 ASC patients with eligible survival data for the first-generation TKIs, the median progression-free survival (PFS) was 9.3 months (95% CI 6.7-11.9), which was rather similar to the data of adenocarcinoma (9.3 vs 11.4 months, p = 0.294) in our institution as opposed to squamous cell carcinoma (9.3 vs 4.9 months, p < 0.001). The objective response rate (ORR) was 37.9% (11/29), and the disease control rate (DCR) was 86.2% (25/29). After progression on the initial EGFR TKIs, 42.1% of the cases (8/19) had an EGFR T790M mutation detected. A median PFS of 10.2 months (95% CI 5.8-14.5, n = 8) was achieved with treatment using the third-generation TKI. The ORR and DCR were 37.5% (3/8) and 100% (8/8), respectively. The median overall survival reached 38.3 months (95% CI 13.7-62.9).

CONCLUSIONS

Targeted therapy showed remarkable efficacy in ASC patients harboring sensitive EGFR mutations, comparable to adenocarcinoma. The application of the third-generation TKI provided an option to prolong survival.

Clinicopathological Characteristics And EGFR-TKIs Efficacies In Lung Squamous Cell Carcinoma Patients Harboring An EGFR Sensitizing Mutation

Objective

This study analyzed the relationship between the clinicopathological features and epidermal growth factor receptor (EGFR) mutation status of squamous cell lung cancer (SqCLC) patients. Mutation status was analyzed by comparing the amplification refractory mutation system-polymerase chain reaction (ARMS-PCR) and next-generation sequencing (NGS). We also assessed the efficacies of EGFR tyrosine kinase inhibitors (TKIs).

Methods

Retrospective analysis was performed for 292 SqCLC patients treated at the Guangxi Medical University Affiliated Tumor Hospital from December 2013 to December 2018. The EGFR mutations in tumor tissues were identified by ARMS-PCR and NGS. The affiliation between EGFR mutation and clinicopathological features was analyzed. Efficacies of EGFR-TKIs and survival were evaluated using the benchmarks of response evaluation criteria in solid tumors 1.1 (RECIST 1.1) and the Kaplan–Meier method, respectively.

Results

Among the 292 SqCLC patients, 24 (8.2%) were identified to have an EGFR-sensitizing mutation. Both ARMS-PCR and NGS were equally effective in detecting EGFR mutations. Females and non-smokers had higher EGFR mutation rates than males and smokers (22.1% vs. 5.1%, P = 0.007 and 16.7% vs. 4.5%, P = 0.001, respectively). EGFR mutation was unrelated to the degree of differentiation, clinical stage, specimen type and level of serum carcino-embryonic antigen (CEA) and squamous cell carcinoma antigen (SCC) (P > 0.05). In the 14 EGFR mutant cases treated with EGFR-TKIs, the objective response rate (ORR) and disease control rate (DCR) were 28.6% and 78.6%, respectively. Median progression-free survival (mPFS) and overall survival (mOS) were 4.9 and 10.75 months, respectively, with fine tolerance and mild side-effects.

Conclusion

EGFR-sensitizing mutations are rare in SqCLC patients with females and non-smokers having a higher risk of harboring them. There was no difference in the detection rates of EGFR for both the ARMS-PCR and NGS methods. EGFR-TKIs showed modest efficacies and low toxicity profiles in EGFR mutant cases.

Characteristics and Response to Crizotinib in ALK-Rearranged, Advanced Non-Adenocarcinoma, Non-Small Cell Lung Cancer (NA-NSCLC) Patients: a Retrospective Study and Literature Review

BACKGROUND

Oncogenic fusion genes consisting of echinoderm microtubule-associated protein-like 4 (EML4) and anaplastic lymphoma kinase (ALK) can be detected in 5-7% of lung adenocarcinoma cases. The prevalence of ALK rearrangement in non-adenocarcinoma, non-small cell lung cancers (NA-NSCLC) is currently unknown. In addition, the efficacy of crizotinib in these patients has not been well established.

OBJECTIVES

The aim of this study was to investigate the prevalence of ALK rearrangement in NA-NSCLC patients and the therapeutic efficacy of crizotinib in these patients.

METHODS

We included NA-NSCLC patients who were tested for the presence of ALK rearrangement in our institution from January 2013 to May 2018. The effectiveness of crizotinib in ALK-positive patients was retrospectively analyzed. A literature review was performed and eligible previously published cases were analyzed in combination with our data.

RESULTS

A total of 4662 patients were screened and 1696 NA-NSCLC patients were tested for the presence of ALK rearrangement during the study period. Thirty-two positive patients were identified (1.9%, 95% CI, 1.2-2.5%). A statistically higher percentage of younger (58.0 vs. 63.0, p = 0.01), female patients (53.1% vs. 10.8%, p < 0.01) who were non-smokers (71.9% vs. 40.6%, p < 0.01) and whose tumors contained adenocarcinoma components (34.4% vs. 6.1%, p < 0.01) were observed in the ALK-positive group. Eighteen patients were excluded from the study and 14 eligible patients were included for survival analysis. The median duration of crizotinib treatment (MDT) as a proxy for progression-free survival of the 14 eligible patients in our institution was 6.0 months (95% CI, 1.2-10.8 months). We combined our data with sporadic cases from 16 previous publications (total n = 37) and found that the MDT was 7.0 months (95% CI, 6.0-8.0 months).

CONCLUSIONS

Our study suggests the opportunity to test ALK rearrangement in NA-NSCLC patients, especially in younger, female, non-smoking patients containing adenocarcinoma components. Crizotinib provides an option for the treatment of NA-NSCLC patients who have an ALK rearrangement.

The Japanese Lung Cancer Society Guideline for non-small cell lung cancer, stage IV

According to rapid development of chemotherapy in advanced non-small cell lung cancer (NSCLC), the Japan Lung Cancer Society has been updated its own guideline annually since 2010. In this latest version, all of the procedure was carried out in accordance with grading of recommendations assessment, development and evaluation (GRADE) system. It includes comprehensive literature search, systematic review, and determination of the recommendation by multidisciplinary expert panel which consisted of medical doctors, pharmacists, nurses, statisticians, and patients from patient advocacy group. Recently, we have had various types of chemotherapeutic drugs like kinase inhibitors or immune-checkpoint inhibitors. Thus, the guideline proposes to categorize patients into three entities: (1) driver oncogene-positive, (2) PD-L1 ≥ 50%, and (3) others. Based on this subgroup, 31 clinical questions were described. We believe that this attempt enables clinicians to choose appropriate treatment easier. Here, we report an English version of the Japan Lung Cancer Society Guidelines 2018 for NSCLC, stages IV.

Uncommon Types of Lung Carcinoma With Mixed Histology: Sarcomatoid Carcinoma, Adenosquamous Carcinoma, and Mucoepidermoid Carcinoma

CONTEXT

- Lung tumors are histologically heterogeneous, but classification of lung carcinoma has prognostic impact and increasingly, specific molecular correlates.

OBJECTIVE

- To update the gross, microscopic, and molecular pathology of unusual lung carcinomas to assure accurate classification. In entities with mixed histology, the recognition of specific features or rare patterns is critical to diagnosis. These diagnoses can identify tumors with aggressive clinical behavior, and diagnostic pitfalls can therefore result in underdiagnosis of these already rare entities. Incorrect classification of more indolent tumors into the more aggressive categories can also occur. In the area of molecular pathology, these unusual tumors have a specific spectrum of molecular alterations.

DATA SOURCES

- PubMed searches for lung and sarcomatoid carcinoma, pleomorphic carcinoma, blastoma, carcinosarcoma, and adenosquamous and mucoepidermoid carcinoma were undertaken and this information was integrated with clinical experience of the author.

CONCLUSIONS

- These uncommon carcinomas have specific clinicopathologic features, and attention to their gross and microscopic pathology leads to classification with important associated molecular findings.

Curative effectiveness and safety of osimertinib in the treatment for non-small-cell lung cancer: a meta-analysis of the experimental evidence

Background

Osimertinib is an EGFR-TKI that is selective for both EGFR-TKI-sensitizing and T790M resistance mutations in patients with non-small-cell lung cancer (NSCLC). The purpose of this study was conducting a meta-analysis to evaluate the clinical efficacy and safety of osimertinib in the treatment for NSCLC.

Methods

Using “osimertinib” as a keyword combined with “non-small-cell lung cancer” and “randomized controlled trial” as medical subject headings, the following electronic databases were searched: PubMed, EMBASE, Cochrane Library, and China National Knowledge Infrastructure. After data extraction and quality assessment of the included randomized controlled trials, the RevMan 5.3 software and R meta package were applied for meta-analysis of objective response rate (ORR), disease control rate (DCR), progression-free survival (PFS), overall survival (OS), and safety.

Results

Ten studies met our criteria and were included in the meta-analysis, with a total of 3,260 participants. The meta-analysis showed that osimertinib therapy was superior to the control therapy alone in ORR (combined RR=1.53, 95% CI: 0.87–2.71, P=0.14), DCR (combined RR=1.07, 95% CI: 0.79–1.44, P=0.66), PFS (combined RR=0.32, 95% CI: 0.24–0.44, P<0.00001), and OS (combined RR=0.57, 95% CI: 0.47–0.70, P<0.00001). In addition, osimertinib led to some toxicities, and the overall prevalence of all-grade diarrhea was 40% (95% CI: 33–47), paronychia 26% (95% CI: 20–33), rash 40% (95% CI: 34–47), dry skin 28% (95% CI: 23–33), and stomatitis 15% (95% CI: 9–23).

Conclusion

Our study showed that osimertinib demonstrated a significant improvement in the ORR, DCR, PFS, and OS with tolerable adverse effects for NSCLC patients. However, because of some clear limitations (heterogeneity and publication bias), these results should be interpreted with caution.

Lung cancer in never smokers-the East Asian experience

Approximately one third of all lung cancer patients in East Asia are never-smokers. Furthermore, the proportion of lung cancer in never smokers (LCINS) has been increasing over time. Never-smokers are more often diagnosed with adenocarcinoma in East Asia, a subtype largely defined by oncogenic drivers. In this subgroup of patients, as high as 90% of patients have been found to harbor well-known oncogenic mutations and can be successfully managed with targeted therapies inhibiting specific oncogenic mutant kinases. EGFR tyrosine kinase inhibitor (EGFR-TKI) treatment has been the most important targeted therapy in lung adenocarcinoma from East Asian never-smokers as approximately 70% of these patients have the opportunity to receive EGFR-TKI treatment. Lung squamous cell carcinoma (SQCC) and small cell lung cancer (SCLC) are two common histologic types of smoking-related non-small cell lung cancer (NSCLC). The proportion of never-smokers with SQCC and SCLC in East Asian patients seems to be higher than that in Caucasian patients. Recent studies also suggest that lung SQCC and SCLC in never-smokers may be distinct subtypes. Therefore, better understanding of the biologic characteristics of these subtypes of patients may provide new insights for the treatment. In this review, we will provide an overview of East Asian experience in the treatment of advanced, never-smoking lung cancer, focusing on etiologic factors in the development of LCINS, targeted therapy for never-smokers with adenocarcinoma, distinct characteristics of never-smokers with lung SQCC and SCLC, and the role of immunotherapy in never-smokers with NSCLC.

EGFR mutations subset in Chinese lung squamous cell carcinoma patients

Research has identified that epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs) possess large benefits for adenocarcinoma (ADC), although little benefit for squamous cell carcinoma (SCC). The aim of the present study was to investigate the percentage of patients with SCC with the EGFR mutations subset and the benefits of EGFR TKIs in SCC. In the present study, the EGFR mutations subset was detected with an amplification refractory mutation system in 1,359 clinical SCC tissues. The association of the EGFR mutations subset with clinicopathological parameters was evaluated using the Mann-Whitney U test, and Kruskal-Wallis H. Kaplan-Meier survival analysis was used to estimate the effect of the EGFR mutations subset on SCC patient survival rates. A total of 94 out of 1,359 SCC patients were identified as having EGFR mutations, an EGFR mutation rate of 6.92%. The EGFR mutations subset in the 94 cases was identified as follows: 37.2% (35/94) in exon 19; 39.4% (37/94) in L858R; 5.3% (5/94) in T790M; 4.3% (4/94) in G719X; 2.1% (2/94) in L861Q; and 11.7% (11/94) in other mutations. Kaplan-Meier survival analysis identified that the differentiation, pathological tumor, node, metastasis stage, lymph node metastasis and distant metastases were significantly associated with patients' survival (P>0.05; log-rank test), and no significant difference was observed between TKI therapy and chemotherapy in terms of patient survival rates (P>0.05). In addition, the overall discordant rate of the EGFR mutations subset in SCC patients was relatively low. Due to the non-significant difference between TKI therapy and chemotherapy in terms of patient survival and the lower discordance rate of the EGFR mutations subset in SCC patients, EGFR TKIs could be a recommended treatment for SCC.

EGFR with TKI-sensitive mutations in exon 19 is highly expressed and frequently detected in Chinese patients with lung squamous carcinoma

Recently, tyrosine kinase inhibitors (TKIs) have been recommended as a first-line treatment for advanced non-small cell lung cancer (NSCLC), significantly improving the treatment outcomes of lung adenocarcinoma patients with the EGFR mutation. However, the application of TKIs for lung squamous cell carcinoma (SCC), the second largest pathological subtype of NSCLC, remains controversial because available data for the EGFR mutation profile and frequency in SCC patients are limited. In this study, 89 bronchoscopic-biopsy specimens from Chinese SCC male patients were assayed for EGFR exon 19 mutation, using improved polymerase chain reaction-denature gel gradient electrophoresis. EGFR exon 19 mutations were detected in 77 of 89 (86.5%) patients, and included six kinds of point mutations (11.6%) and two deletions (Del_747-751 [64.9%] and Del_746-751 [23.3%]). We found that the proportion of mutated EGFR varied from 0.98% to 100% in positive specimens and increased with the development of the disease. The difference of proportion between Stage IV patients and Stage II patients or Stage III patients was significant (P<0.001). These results provided valuable clues to explain the reason why patients harboring the same mutation responded distinctly to TKI treatment. Del_747-751 and Del_746-751 were the dominant mutations in the assayed SCC patients (76.4%), and both belong to the EGFR-TKI-sensitive mutation. Recently research demonstrated that Del_746-751 patients have better response to EGFR-TKI than Del_L747-751 patients. However, our study indicated that majority of SCC patients (55.5%) carried Del_ L747-751. We suggest that the unique clinic features of SCC should be further studied to reveal the mechanism of poorer treatment outcome of EGFR-TKI therapy, and that a better treatment plan and more specific, potent targeted drugs for lung SCC need to be developed.

Efficacy of epidermal growth factor receptor (EGFR)-tyrosine kinase inhibitors (TKIs) in targeted therapy of lung squamous cell carcinoma patients with EGFR mutation: a pooled analysis

PURPOSE

This pooled analysis aims to evaluate the efficacy of epidermal growth factor receptor (EGFR)-tyrosine kinase inhibitors (TKIs) in lung squamous cell carcinoma with EGFR mutation.

METHODS

Advanced stage (IIIB/IV) lung squamous cell carcinoma patients with EGFR mutations treated with EGFR-TKIs were extracted from the publications searched from the databases of EMBASE, Medline (Ovid SP), Web of Science, Cochrane library, PubMed Publisher, ASCO meeting abstract and Google Scholar before August 2016, or identified from the database of Shanghai Chest Hospital from July 2014 to August 2016. Pooled objective response rate, disease control rate and median progression-free survival were accessed directly or by Kaplan-Meier method and combined in different studies by Comprehensive Meta Analysis software via one-group dichotomous or continuous analysis functions.

RESULTS

The combined objective response rate, disease control rate and median progression-free survival were 31.6% (95%CI, 24.1%∼40.2%), 72.0% (95% CI, 63.5%∼79.2%) and 3.08 months (95% CI, 2.31-3.84 months) in lung squamous cell carcinoma patients with EGFR mutation.

CONCLUSION

The EGFR-TKIs had a modest response for EGFR mutated lung squamous cell carcinoma patients and might be a selective option for those patients.

Clinical efficacy evaluation of tyrosine kinase inhibitors for non-adenocarcinoma lung cancer patients harboring EGFR-sensitizing mutations

Epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs) as a standard therapy have been used in EGFR-mutated adenocarcinoma of non-small-cell lung cancer (NSCLC) patients in recent years. But in current randomized prospective clinical trials, due to few cases of non-adenocarcinoma patients having been found, the efficacy of TKIs for EGFR-mutated non-adenocarcinoma and the relationship with clinicopathological characteristics remained debatable. The results of retrospective studies showed that the frequency of EGFR mutation was significantly associated with nationality, gender, smoking history, and histology type. Being female, never-smoker and adenocarcinoma had a higher mutation rate. Furthermore, the EGFR mutation rate and efficacies of TKIs in adenocarcinoma were higher than those in non-adenocarcinoma. And in non-adenocarcinoma, the EGFR mutation rate and efficacies of TKIs in adenosquamous cell carcinoma were higher than those in squamous cell carcinoma or in large-cell lung carcinoma. In conclusion, it may be necessary to conduct a large sample prospective study to understand the clinicopathological characteristics of non-adenocarcinomas and to evaluate the efficacy of EGFR TKI and/or chemotherapy for EGFR-mutated non-adenocarcinoma NSCLC. So we searched relevant articles between the year 2010 and 2016 through the major indexed literature database PubMed by searching the keywords such as EGFR mutation, Tyrosine kinase inhibitors, and Non-adenocarcinoma.

EGFR mutation in squamous cell carcinoma of the lung: does it carry the same connotation as in adenocarcinomas?

BACKGROUND

EGFR tyrosine kinase inhibitors (TKIs) have greatly improved the outcomes of EGFR mutation-positive adenocarcinomas of the lung. In contrast, the significance of EGFR mutation in metastatic squamous cell carcinoma (SCC) of the lung has been debated.

METHODS

All patients with metastatic SCC who underwent EGFR mutation testing at our center from 2010 to 2015 were included for analysis. EGFR kinase domain mutations were tested using Taqman-based real-time polymerase chain reaction (PCR). Response assessment was done using Response Evaluation Criteria In Solid Tumors (RECIST) 1.1. Kaplan-Meier method was used for calculating progression-free survival (PFS) and overall survival (OS).

RESULTS

EGFR mutation was detected in 29 out of 639 patients with SCC. Furthermore, 19 out of the 29 patients received TKIs at some point during their treatment. TKI therapy led to a partial response in 5 out of 19 patients and stable disease in 4 out of 19 patients. The median PFS of patients treated with TKIs was 5.0 months. The median OS of the whole EGFR-positive SCC cohort was 6.6 months. On univariate analysis, patients having received TKI therapy was the only factor associated with a significantly better OS of 13.48 months versus 2.58 months (P=0.000). On multivariate analysis, patients receiving TKI therapy, Eastern Cooperative Oncology Group-Performance Scale (ECOG-PS) score <2, EGFR exon 19 mutation and nonsmoking status were associated with significantly better OS.

CONCLUSION

EGFR mutation in SCC of the lung predicts a better outcome if the patient is given TKI, but it may be inferior to the outcomes seen in EGFR-positive adenocarcinomas treated with TKI.