Analysis of the Relationship Between the Quality of Small Biopsy Specimens of Non-small Cell Lung Cancer and the Mutation Rate of EGFR Gene / 中国肺癌杂志

BACKGROUND@#Epidermal growth factor receptor (EGFR) is the gene with the highest mutation rate in non-small cell lung cancer (NSCLC) patients, and the accurate evaluation of its mutational status can facilitate patients receiving targeted drug therapy and thereby prolong patients' survival. The gene testing platform has adequacy requirements for the specimen quality in order to obtain accurate examination results. It has been reported that the number and proportion of tumor cells in samples will affect the detection rate of EGFR gene mutation. The present study aims to analyze the relationship between the quality of small biopsy specimens of NSCLC and the mutation rate of EGFR gene with amplification refractory mutation system (ARSM) test.@*METHODS@#After collecting the clinical characteristics of 299 cases small biopsy of lung adenocarcinoma, DNA concentration of the specimens and the mutational status of EGFR gene, the number and proportion of tumor cells in HE stained sections evaluated using light microscopy, the relationship between specimen quality and the mutation rate of EGFR gene were analyzed.@*RESULTS@#The mutation rates of EGFR for the groups with tumor cell number ≤500 and >500 were 40.7% (11/27) and 43.8% (119/272) respectively, without significant difference (P=0.764). The mutation rates for the groups with DNA concentration ≤20.4 ng/μL and >20.4 ng/μL were 42.7% (64/150) and 44.3% (66/149) respectively, without significant difference (P=0.776). The mutation rates for the groups with tumor cells proportion ≤30% and >30% were 29.4% (20/68) and 47.6% (110/231) respectively, demonstrating significant difference (P=0.008). Multivariate Logistic analysis showed that male, thyroid transcription factor-1 (TTF-1) negative, smoking history and tumor cell proportion less than 30% were main factors that contributes to the low detection rate of EGFR gene mutation.@*CONCLUSIONS@#After meeting the minimum requirements for detection, the EGFR mutation rate is affected by the proportion of tumor cells in the sample. Therefore, it is necessary to re-evaluate the tumor cell proportion in the last section after the genetic test section. For samples with lower tumor cell proportion, enriching tumor cells through microdissection and other methods is recommended for a more accurate detection result. For specimens that cannot be enriched with tumor cells, circulating tumor DNA (ctDNA) test can be performed as a supplement. If the result is still negative, another biopsy should be considered to obtain enough tumor specimens for molecular testing.

Which Tyrosine Kinase Inhibitor Must We Apply Before? A Case Report of Crizotinib-resistant Patient with Concomitant EGFR and EML4-ALK Gene Mutations

ABSTRACT The concomitant epidermal growth factor receptor (EGFR) mutation and anaplastic lymphoma kinase (ALK) translocations in lung adenocancers are very rare scenarios. Until now, 42 cases described in the literature have all been treated by different drugs. There is no overall consensus regarding the treatment for this adenocarcinoma subgroup. We report here a case of lung adenocarcinoma with concomitant EGFR mutation in exon 21 (L858R) and ALK rearrangement in primary tumour, EGFR mutation in exon 21 (L858R) and no ALK rearrangement in its synchronous metastasis. We treated this patient with crizotinib as the second-line therapy (after the first line docetaxel-cisplatin chemotherapy), but no response was obtained. The therapeutic choice for the lung adenocancer patients with concomitant EGFR mutation and ALK rearrangement is unclear. Examination of c-ros oncogene 1 mutation can be used as an indicator in the prediction of the crizotinib treatment success. The ALK mutation may not responsible for the resistance to EGFR-tyrosine kinase inhibitors (TKI), and EGFR-TKI can be initiated to EGFR and ALK dual mutant patients as the first treatment.

Rare mutations of epidermal growth factor receptor in epidermal growth factor receptor-tyrosine kinase inhibitor-naive non-small cell lung carcinoma and the response to erlotinib therapy

Context: Epidermal growth factor receptor-tyrosine kinase inhibitors (EGFR-TKIs) are considered to be effective treatments for advanced NSCLC patients with sensitizing EGFR mutations. There are many complex and rare mutations in the EGFR gene. The efficacy of the first-generation EGFR-TKI (erlotinib) is unknown for tumors harboring rare EGFR mutations. Aims: The purpose of this study was to investigate the clinical significance of rare EGFR mutations in EGFR-TKI-naive patients and the efficacy of erlotinib. Settings and Design: Istanbul University, Istanbul Medical Faculty, Department of Medical Oncology, Istanbul/Turkey, and retrospective observational study. Subjects and Methods: We retrospectively analyzed 117 non-small cell lung cancer (NSCLC) patients with EGFR mutations who had not previously used EGFR-TKIs. Exons 18–21 of EGFR were analyzed by polymerase chain reaction and subjected to direct sequencing methods. Statistical Analysis Used: Survival estimates were calculated by the Kaplan–Meier method using SPSS 25 software (IBM SPSS, Chicago, USA). Results: Of 117 patients who had EGFR mutations, 23 patients had rare and complex EGFR mutations. Only 9 of them were treated with erlotinib. Three patients (3.5%) with exon 20 mutations received erlotinib. Two with EGFR-p. Q787Q (SNP ID, rs10251977; c.2361G>A) synonymous mutation in exon 20 were responsive to erlotinib therapy in the second-line setting after first-line chemotherapy. To the best of our knowledge, the present two cases are the first to be reported with lung adenocarcinoma with EGFR-p. Q787Q synonymous mutation responding to erlotinib. Conclusion: NSCLC patients harboring rare EGFR mutations generally did not show consistent or favorable responses to EGFR-TKI. We suggest that this rare synonymous mutation (EGFR-p. Q787Q) is a sensitive EGFR mutation in NSCLC

Efficacy and adverse effects of immune checkpoint inhibitor for advanced epidermal growth factor receptor tyrosine kinase-resistant non-small cell lung cancer / 中国肿瘤临床

Objective: To investigate the efficacy and adverse effects of immune checkpoint inhibitor (ICI) for advanced non-small cell lung cancer (NSCLC) resistant to epidermal growth factor receptor tyrosine kinase inhibitor (EGFR-TKI). Methods: The clinical data of 49 patients with advanced NSCLC who received ICI treatment after EGFR-TKI resistance in the Chinese People's Liberation Army General Hospital from January 2015 to March 2019 were collected. Statistical methods were used to analyze the efficacy and adverse effects of immunotherapy in patients with EGFR TKI-resistant NSCLC, and to clarify the relationship between clinical characteristics and the curative efficacy and prognosis of patients. Results: The objective response rate was significantly higher in patients with combination therapy than those with monotherapy (28.6% vs. 7.1%, P60 years had longer progression free survival than those with moderate differentiation (5.1 vs. 2.8 months, P=0.03), monotherapy (6.8 vs. 2.3 months, P60 years and combination therapy were independent protective factors for PFS (P<0.001). Although combination therapy group had higher overall adverse event rate than monotherapy group, there was no significant difference in the adverse reaction rate of grade 3 and above between both groups (P= 0.28). Conclusions:The efficacy of monotherapy with ICI was poor in EGFR TKI-resistant patients with late-stage NSCLC, while combination therapy could significantly improve the curative efficacy and prognosis of patients. Although the overall rate of adverse events

Results of EGFR Mutations Detected in Pleural Effusion and Its Clinical Significance in 132 Patients with Advanced Non-small Cell Lung Cancer: A Retrospective Study in A Single Center / 中国肺癌杂志

BACKGROUND@#The lack of pathological quality control standard in detecting epidermal growth factor receptor (EGFR) gene mutation in malignant pleural effusion leads to confusion in the interpretation of detection results and the clinical use of EGFR-tyrosine kinase inhibitor (TKI). Therefore, it is very important to propose quality control standards and guide the detection of EGFR mutation in pleural effusion. The aim of this study is to retrospectively analyze the results of EGFR gene mutation in pleural effusion sediment section according to strict pathological quality control standards, and the therapeutic effect of EGFR-TKIs guided by this detection results.@*METHODS@#From January 2012 to June 2018, the clinical data of patients with pleural effusion collected from Department of Pathology of Peking Union Medical College Hospital were analyzed retrospectively. Among them, 132 patients with relatively complete clinical data and with EGFR gene mutation detection of paraffin-embedded pleural effusion sediment section according to the established quality control standard were included. According to the results of EGFR gene mutation, it was divided into positive group and negative group, and the efficacy of EGFR-TKIs in different groups was compared.@*RESULTS@#After the centrifugation of pleural effusion, the sediment was embedded in paraffin, sectioned, and observed under the microscope after HE staining. If the number of tumor cells ≥100, it met the pathological quality control standard, and it could be used for subsequent EGFR gene mutation detection. EGFR gene mutations were detected in 72 (54.5%) of 132 patients. EGFR-TKIs were used in 69 of 72 mutation positive patients. Of 60 EGFR mutation negative patients, only 15 used EGFR-TKIs. In EGFR mutation positive group, the disease control rate (DCR) was 95.8%, and the median progression-free survival (PFS) was 11 months. In EGFR mutation negative group, the DCR was 0%, and the median PFS was 1 month. The DCR and PFS were significantly different between the two groups (P<0.05).@*CONCLUSIONS@#According to the pathological quality control standards, the embedded section of pleural fluid sediment can be used to detect EGFR gene mutation, and the results can be used to guide the clinical use of EGFR-TKIs.

The Association of Acquired T790M Mutation with Clinical Characteristics after Resistance to First-Line Epidermal Growth Factor Receptor Tyrosine Kinase Inhibitor in Lung Adenocarcinoma / Journal of the Korean Cancer Association, 대한암학회지

PURPOSE: The main objective of this study was to investigate the relationship among the clinical characteristics and the frequency of T790M mutation in advanced epidermal growth factor receptor (EGFR)–mutant lung adenocarcinoma patients with acquired resistance after firstline EGFR–tyrosine kinase inhibitor (TKI) treatment. MATERIALS AND METHODS: We enrolled EGFR-mutant stage IIIB-IV lung adenocarcinoma patients, who had progressed to prior EGFR-TKI therapy, and evaluated their rebiopsy EGFR mutation status. RESULTS: A total of 205 patients were enrolled for analysis. The overall T790M mutation rate of rebiopsy was 46.3%. The T790M mutation rates among patients with exon 19 deletion mutation, exon 21 L858R point mutation, and other mutations were 55.0%, 37.3%, and 27.3%, respectively. Baseline exon 19 deletion was associated with a significantly higher frequency of T790M mutation (adjusted odds ratio, 2.14; 95% confidence interval [CI], 1.20 to 3.83; p=0.010). In the exon 19 deletion subgroup, there was a greater prevalence of T790M mutation than other exon 19 deletion subtypes in patients with the Del E746-A750 mutation (61.6% vs. 40.6%; odds ratio, 2.35; 95% CI, 1.01 to 5.49; p=0.049). The progression-free survival (PFS) of first-line TKI treatment > 11 months was also associated with a higher T790M mutation rate (54.1% vs. 39.3%; adjusted odds ratio, 1.82; 95% CI, 1.02 to 3.25; p=0.044). Patients who underwent rebiopsy at metastatic sites had more chance to harbor T790M mutation (52.6% vs. 33.8%; adjusted odds ratio, 1.97; 95% CI, 1.06 to 3.67; p=0.032). CONCLUSION: PFS of first-line EGFR-TKI, rebiopsy site, EGFR exon 19 deletion and its subtype Del E746-A750 mutation are associated with the frequency of T790M mutation.

Dual surrogate markers for rapid prediction of epidermal growth factor receptor mutation status in advanced adenocarcinoma of the lung: A novel approach in resource‑limited setting.

INTRODUCTION: Tyrosine kinase inhibitors have revolutionized the treatment of metastatic lung cancer in patients with epidermal growth factor receptor (EGFR) mutations. Amplified refractory mutation system (ARMS)‑reverse transcription‑polymerase chain reaction (RT‑PCR), the current standard for detecting EGFR mutation status is time‑consuming and highly expensive. Consequently any surrogate test which are cheaper, faster and as accurate as the PCR method will help in early diagnosis and management of patients with lung cancer, especially in resource‑limited settings. MATERIALS AND METHODS: Eighty‑five patients, all of South Indian origin, with adenocarcinoma of lung, registered between October 2009 and January 2013, were evaluated for EGFR mutation status by using scorpion probe based ARMS RT‑PCR method. Immunohistochemical (IHC) was performed using the phosphorylated AKT (P‑AKT) and thyroid transcription factor‑1 (TTF‑1) on above patient’s sample, and the results were compared with EGFR mutation tests. RESULTS: EGFR mutation was positive in 34 of 85 patients (40%). P‑AKT and TTF‑1 were positive in 50 (58.8%) and 68 (80%) patients respectively. Both P‑AKT and TTF‑1 had statistically significant correlation with EGFR mutation status. Positive and negative predictive value of P‑AKT in diagnosing EGFR mutation was 58% and 85.5% and that for TTF‑1 was 48.5% and 94.1%, respectively. The problem of low positive predictive value can partly be overcome by testing P‑AKT and TTF‑1 simultaneously. CONCLUSION: P‑AKT and TTF‑1 using IHC had statistically significant correlation with EGFR mutation with high negative predictive value. In the case of urgency of starting treatment, EGFR mutation testing may be avoided in those patients who are negative for these IHC markers and can be started on chemotherapy.

Genomic profiling in a homogeneous molecular subtype of non‑small cell lung cancer: An effort to explore new drug targets.

BACKGROUND: Patients’ who are positive for kinase domain activating mutations in epidermal growth factor receptor (EGFR) gene, constitute 30–40% of non‑small cell lung cancer (NSCLC), and are suitable candidates for Tyrosine Kinase Inhibitor based targeted/personalized therapy. In EGFR non‑mutated subset, 8–10% that show molecular abnormalities such as EML4‑ALK, ROS1‑ALK, KIP4‑ALK, may also derive the benefit of targeted therapy. However, 40% of NSCLC belong to a grey zone of tumours that are negative for the clinically approved biomarkers for personalized therapy. This pilot study aims to identify and classify molecular subtypes of this group to address the un‑met need for new drug targets in this category. Here we screened for known/novel oncogenic driver mutations using a 46 gene Ampliseq Panel V1.0 that includes Ser/Thr/ Tyr kinases, transcription factors and tumor suppressors. METHODS: NSCLC with tumor burden of at least 40% on histopathology were screened for 29 somatic mutations in the EGFR kinase domain by real‑time polymerase chain reaction methods. 20 cases which were EGFR non‑mutated for TK domain mutations were included in this study. DNA Quality was verified from each of the 20 cases by fluorimeter, pooled and subjected to targeted re‑sequencing in the Ion Torrent platform. Torrent Suite software was used for next generation sequencing raw data processing and variant calling. RESULTS: The clinical relevance and pathological role of all the mutations/variants that include SNPs and Indels was assessed using polyphen‑2/SIFT/PROVEAN/mutation assessor structure function prediction programs. There were 10 pathogenic mutations in six different oncogenes for which annotation was available in the COSMIC database; C420R mutation in PIK3CA, Q472H mutation in vascular endothelial growth factor receptor 2 (VEGFR2) (KDR), C630W and C634R in RET, K367M mutation in fibroblast growth factor receptor 2 (FGFR2), G12C in KRAS and 4 pathogenic mutations in TP53 in the DNA binding domain (E285K, R213L, R175H, V173G). CONCLUSION: Results suggest, a potential role for PIK3CA, VEGFR2, RET and FGFR2 as therapeutic targets in EGFR non‑mutated NSCLC that requires further clinical validation.

Treatment after acquired resistance to EGFR-TKI of non-small cell lung cancer / 中国肿瘤临床

Epidermal growth factor receptor tyrosine-kinase inhibitors (EGFR-TKIs) have elicited curative effects on patients with advanced non-small celllung cancer and with activating mutations in the EGFR gene. However, acquired resistance to EGFR-TKIs is eventually developed after an initial response is induced;as such, patients with acquired resistance must be treated with more ef-fective strategies to delay or possibly overcome the resistance. This article reviews available data on the treatment of patients who have failed to respond to EGFR-TKI.

Relationship between EGFR protein phosphorylation,EGFR mutation and EGFR-TKI efifcacy in advanced non-small cell lung cancer / 中国癌症杂志

Background and purpose:EGFR-TKI (EGFR-tyrosine kinase inhibitors), represented by geiftinib and erlotinib, have exhibited signiifcant antiproliferative effects against non-small cell lung cancer (NSCLC) with low toxicity.EGFR gene mutation was discovered to be a predictive biomarker for EGFR-TKI treatment. Although the efifcacy of EGFR-TKI is limited toEGFR wild-type patients, it is still noticeable suggesting that some other mechanisms are responsible for it. The current study is aimed at evaluating the expression of phosphorylated EGFR in advanced NSCLC, investigating its relationship withEGFR mutations and EGFR-TKI efifcacy.Methods:EGFR gene mutations were detected by denaturing high performance liquid chromatography (DHPLC) in 205 stageⅢB-ⅣNSCLC patients. The expressions of phosphorylated tyrosine 1068 (pTyr1068) and 1173 (pTyr1173) were detected by immunohistochemistry.Results:The positive expressions of pTyr1068 and pTyr1173 were 80.0% (164/205) and 57.6% (95/165) respectively. None of them were related to clinical pathological characteristics (age, gender, pathological type, smoking status, disease stage).EGFR gene mutation rate was 44.9% (92/205), which was only related to smoking status (P=0.024) compared to other clinical pathological characteristics.EGFR gene mutations were poorly related to pTyr1068 expression (P<0.001) and not related to pTyr1173 expression (P=0.297). The objective response rate (ORR),disease control rate (DCR), and progressive free survival (PFS) of EGFR-TKI treatment in patients withEGFR mutations were 48.3% (43/89), 80.9% (72/89) and 8 months (95%CI: 6.11-11.42) respectively, which were signiifcantly higher than that ofEGFR wild-type patients [ORR=16.2% (17/105,P<0.001); DCR=56.2%(59/105,P<0.001); Median PFS: 2.1 months, (95%CI: 0.89-3.24;P=0.001)]. Superior ORR: DCR and PFS appeared in patients with pTyr1068 positive expression compared to negative [ORR: 37.7% (58/154)vs 5.0% (2/40,P<0.001); DCR: 74.7% (115/154)vs 40.0% (16/40,P<0.001); Median PFS: 7.0 monthsvs 1.2 months,P<0.001)]. Inversely, the patients with pTyr1173 positive expression had lower ORR, DCR and shorter PFS [ORR: 27.8% (25/90)vs 37.9%(25/66,P=0.123); DCR: 64.4% (58/90)vs 83.3% (55/66,P=0.007); Median PFS: 4.8 monthsvs 7.7 months (P=0.016)]. In subgroup ofEGFR wild-type patients, positive expression of pTyr1068 was 69.0% (69/100).EGFR wild-type patients with pTyr1068 positive expression had a prolonged PFS and elevated ORR and DCR compared to negative [median PFS: 3.6 monthsvs 1.2 months (P<0.001); ORR: 23.2%vs 3.2% (P=0.010); DCR: 69.6%vs 35.5% (P=0.001)]. Sixteen patients with pTyr1068 positive expression who responded to EGFR-TKI treatment in this subgroup had a remarkable PFS [median PFS: 15.6 months (95%CI:7.28-23.9)]. Multiple factor analysis showed that the expression of pTyr1068 was an independence predictor factor for EGFR-TKI treatment (OR=0.24, 95%CI: 0.16~0.37,P<0.001). Conclusion:Phosphorylation at Tyr1068 of EGFR might be a potential predictive factor for clinical response and survival of EGFR-TKI treatment in patients with advanced NSCLC, especially inEGFR wild-type patients.

A Case of Gefitinib (Iressa(R))-associated Tumor Lysis Syndrome in Adenocarcinoma of the Lung / 영남의대학술지

The tumor lysis syndrome has been described as biochemical disturbances associated with rapid destruction of tumor cells and subsequent synchronized massive release of cellular breakdown products sufficient to overwhelm excretory mechanisms and the body's normal reutilization capacity. The cardinal signs of the tumor lysis syndrome are hyperkalemia, hyperphosphatemia, hypocalcemia and hyperuricemia. Gefitinib (Iressa) is an oral, selective epidermal growth factor receptor (EGFR) inhibitor that has activity in female, non-smoker and non-small cell lung cancer with an EGFR mutation. Gefitinib is a well tolerated drug with few side effects. It has been associated with skin rash, diarrhea, nausea, a decrease in liver function and interstitial lung disease. However, there is no prior report of the tumor lysis syndrome associated with gefitinib. We report a case of a 54 year-old woman who developed tumor lysis syndrome that might have been induced by gefitinib after the treatment of adenocarcinoma of lung with an EGFR mutation.