Chinese Non-small Cell Lung Cancer Research Articles

169P Analysis of tumor immune microenvironment with mIHC in Chinese non-small cell lung cancer

169P Analysis of tumor immune microenvironment with mIHC in Chinese non-small cell lung cancer

Befotertinib in first-line treatment for Chinese non-small cell lung cancer patients harboring common EGFR-mutations reveals similar efficacy to other third-generation EGFR-TKIs but somewhat different safety profile.

Befotertinib in first-line treatment for Chinese non-small cell lung cancer patients harboring common EGFR-mutations reveals similar efficacy to other third-generation EGFR-TKIs but somewhat different safety profile.

Comprehensive analysis of next generation sequencing and ARMS-PCR for detecting EGFR exon 20 insertion (ex20ins) mutations in Chinese non-small cell lung cancer patients

Comprehensive analysis of next generation sequencing and ARMS-PCR for detecting EGFR exon 20 insertion (ex20ins) mutations in Chinese non-small cell lung cancer patients

A large-scale, multicenter characterization of BRAF G469V/A-mutant non-small cell lung cancer.

Mutated BRAF is identified in 1%-5% non-small cell lung cancer (NSCLC) patients, with non-V600 mutations accounting for 50%-70% of these. The most common non-V600 mutation is BRAF G469V/A. Currently, there are no targeted therapies available for non-V600 mutated patients. A recent report provided interesting preclinical evidence revealing sensitivity of BRAF G469V to epidermal growth factor receptor (EGFR) inhibitors, raising the possibility of repurposing anti-EGFR agents. It is therefore worthy to characterize the clinical and molecular features of BRAF G469V/A-mutant NSCLC to provide more insights for precision therapy. We conducted a retrospective screening of 25,694 Chinese patients with advanced or metastatic NSCLC to identify individuals with mutated BRAF. Additionally, we performed similar screenings on patients with adenocarcinoma (LUAD) from The Cancer Genome Atlas (TCGA) cohort (n = 567) and the MSKCC cohort (n = 1152). Subsequently, we characterized the clinical and molecular features of the patients carrying BRAF mutations. BRAF G469V was identified in 28 (0.1%) patients from the Chinese NSCLC cohort and 5 (0.9%) from TCGA-LUAD. Notably, none was identified in the MSKCC cohort. G469A was found in 79 (0.3%) Chinese patients, 2 (0.4%) from TCGA-LUAD, and 9 (0.8%) from the MSKCC cohort. Relative allele frequency analysis suggested most BRAF mutations as driven clones. Tumor mutation burden (median 4 mutations/Mb) was not significantly different between patients carrying G469V, G469A, V600E, or other BRAF mutations. Surprisingly, KRAS mutations were found in approximately 50% of patients with G469V mutation and about 8% of patients with G469A mutation, representing a prominent potential resistance mechanism against EGFR inhibitors. Structural modeling suggested BRAF G469V and G469A as binding partners of gefitinib. Our large-scale analysis characterized the prevalence and mutational landscape of BRAF G469V/A-mutant NSCLC and proposed gefitinib as a potential option, providing a basis for further investigations on treating BRAF-mutated NSCLC.

Survival and safety analysis of COVID-19 vaccine in Chinese patients with non-small cell lung cancer.

Severe acute respiratory syndrome coronavirus 2 disease (COVID-19) has caused a worldwide challenging and threatening pandemic. We aimed to assess the safety and efficacy of the COVID-19 vaccines in Non-Small Cell Lung Cancer (NSCLC) patients. Patient self-reported adverse events related to vaccines were recorded by follow-up through a uniform questionnaire. Survival analysis was performed by Kaplan-Meier method. A multivariate analysis was performed by the Cox proportional hazard regression model to determine the effect of each variable on the survival of lung cancer patients. A total of 860 patients with NSCLC on treatment were enrolled. Mean age was 57 years in patients with early stage group and 62 years in advanced stage group. The vaccination rate was 71.11% for early-stage patients and 19.48% for advanced-stage patients; most of them (86.5%) received the COVID-19 inactivated virus (Vero cell) vaccine (Coronavac; Sinovac). The most common systemic adverse reaction was weakness. The main reason for vaccine refusal in those unvaccinated patients was concern about the safety of vaccination in the presence of a tumor and undergoing treatment (56.9% and 53.4%). The 1-year disease-free survival (DFS) rate was 100% for vaccinated and 97.4% for unvaccinated early-stage patients. Then we compared the progression-free survival (PFS) of vaccinated (median PFS 9.0 months) and unvaccinated (median PFS 7.0 months) advanced stage patients (p = 0.815). Advanced NSCLC patients continued to be divided into groups receiving radio-chemotherapy, immunotherapy, and targeted therapy, with no statistical difference in PFS between the groups (p > 0.05). The median overall survival (OS) of vaccinated patients was 20.5 months, and that of unvaccinated patients was 19.0 months (p = 0.478) in advanced NSCLC patients. COVID-19 vaccination is safe for Chinese NSCLC patients actively receiving different antitumor treatments without increasing the incidence of adverse reactions, and vaccination does not affect cancer patient survival.

Chinese expert consensus on iruplinalkib for the treatment of locally advanced or metastatic ALK-positive non-small cell lung cancer (2024 edition)

Anaplastic lymphoma kinase (ALK) fusion gene is one of the most common driver gene in non-small cell lung cancer (NSCLC). Epidemiological data showed that ALK gene fusion is detected in 9.06% of Chinese advanced NSCLC patients. ALK-tyrosine kinase inhibitors (TKIs) have become the standard treatment for advanced NSCLC patients with ALK gene fusion. Seven different ALK-TKIs have been approved by the National Medical Products Administration (NMPA) of China, including crizotinib, ceritinib, alectinib, ensartinib, brigatinib, lorlatinib, and iruplinalkib. Iruplinalkib is a novel new-generation ALK-TKI independently developed in China. On June 27, 2023, the NMPA approved iruplinalkib for the treatment of locally advanced or metastatic ALK-positive NSCLC patients whose disease has progressed after previous treatment with crizotinib or who are intolerant to crizotinib. On January 16, 2024, the NMPA approved iruplinalkib for the first-line treatment of locally advanced or metastatic ALK-positive NSCLC patients. In order to better understand the efficacy and safety of iruplinalkib, and facilitate more rationally clinical application of iruplinalkib, the Medical Oncology Branch of China International Exchange and Promotive Association for Medical and Health Care and the Chinese Association for Clinical Oncologists co-organized experts to compile the "Chinese expert consensus on iruplinalkib for the treatment of locally advanced or metastatic ALK-positive non-small cell lung cancer (2024 edition)".

Abstract 6499: The landscape of MET exon 14 skipping mutations in non-small cell lung cancer patients identified by next-generation sequencing

Abstract Background: MET exon 14 skipping mutations (METex14) account for approximately 0.9%-4% in patients with non-small cell lung cancer (NSCLC). The primary detection methods are DNA and RNA-based next-generation sequencing (NGS). However, the effect of amplicon-based library construction (ALC) and capture-based library construction (CLC) on the detection characteristics of METex14 during the NGS process is not yet fully understood. Here we described the landscape of METex14 in NSCLC patients, as identified by NGS using two different library construction methods. Methods: A total of 6811 samples with NSCLC were enrolled in this study, including 3839 samples performed by DNA-based NGS with CLC, 64 samples performed by RNA-based NGS with CLC and 2908 samples performed by the synchronous DNA-based and RNA-based NGS with ALC. Only the pathogenic mutations and likely pathogenic mutations in clinical significance were rolled into our analysis. Results: The ranking of different methods, as determined by the positive rates for METex14, was RNA-based NGS with ALC (71/2908, 2.44%), RNA-based NGS with CLC (1/64, 1.56%), DNA-based NGS with CLC (54/3839, 1.41%) and DNA-based NGS with ALC (14/2908, 0.48%). Out of 2908 samples performed by the synchronous DNA-based and RNA-based NGS with ALC, 73 samples (2.51%) had METex14 detected at either the DNA or RNA level. METex14 were only detected at the RNA level in 59 patients, while they were only detected at the DNA level in 2 patients. This might be due to the limited probe design at DNA level and the Y1003 site which could not be detected at RNA level. As revealed by DNA-based NGS, the mutation forms causing METex14 include point mutations, indels, and large segment duplications. And the highest mutation rate is in the splice donor site (30.9%), the lowest is observed at position Y1003 (2.9%). Additionally, METex14 is more prevalent in patients over 60 years of age in Chinese NSCLC, with a statistically significant difference (P=0.0043). Conclusion: RNA-based detection of MET 14 skipping yielded a higher detection rate compared to DNA-based NGS, regardless of ALC or CLC. Combining DNA and RNA analysis is more suitable for detecting MET exon 14 skipping and increases the positive rate. Citation Format: Chen Shi, Gao Ning, Zong Qinglan. The landscape of MET exon 14 skipping mutations in non-small cell lung cancer patients identified by next-generation sequencing [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 6499.

EGFR and ERBB2 Exon 20 Insertion Mutations in Chinese Non-small Cell Lung Cancer Patients: Pathological and Molecular Characterization, and First-Line Systemic Treatment Evaluation.

Data from studies looking at both EGFR and ERBB2 exon 20 insertion mutations (-20ins) in the same cohort of patients with non-small cell lung cancer (NSCLC) are limited. The purpose of this study was to analyze EGFR/ERBB2-20ins in all-stage NSCLC patients to reveal their histological and molecular features, and to retrospectively evaluate the results of first-line real-world systemic treatments in patients with advanced-stage disease. We collected 13,920 formalin-fixed paraffin-embedded NSCLC specimens. Clinicopathological features were recorded and DNA-based next-generation sequencing was performed. First-line systemic treatment data were obtained via chart review. In total, 414 (2.97%) EGFR-20ins cases and 666 (4.78%) ERBB2-20ins cases were identified. Both were more common in women, non-smokers, and patients with adenocarcinoma. The incidence of EGFR/ERBB2-20ins in adenocarcinoma is inversely proportional to the degree of invasion; 77 and 26 variants were detected in EGFR-20ins and ERBB2-20ins cases, respectively. The most common concurrently mutated genes were TP53 and RB1. In invasive adenocarcinoma, lepidic components were more common in EGFR/ERBB2-20ins-alone cases than in those with other concurrent mutated genes. In EGFR-/ERBB2-20ins patients, there was no significant difference in progression-free survival (PFS) or treatment response to first-line systemic treatments in this study. There was no significant difference in PFS or treatment response among patients with different EGFR/ERBB2-20ins variants and those with or without concurrent mutated genes. EGFR/ERBB2-20ins is more common in early lung adenocarcinoma. EGFR-20ins had more variants. In both cohorts, the results for first-line systemic treatments showed no significant difference.

PD-L1 expression and its correlation with clinicopathological and molecular characteristics in Chinese patients with non-small cell lung cancer.

Little is known about the relationship between programmed cell death-ligand 1 (PD-L1) expression and histologic and genetic features in real-world Chinese non-small cell lung cancer patients. From November 2017 to June 2019, tumor tissues were collected from 2674 non-small cell lung cancer patients. PD-L1 expression was detected with immunohistochemistry using the 22C3 and SP263 antibodies, and patients were stratified into subgroups based on a tumor proportion score of 1%, 1% to 49%, and ≥ 50%. Genetic alterations were profiled using targeted next-generation sequencing. In the total population, 50.5% had negative PD-L1 expression (tumor proportion score < 1%), 32.0% had low-positive expression (1%-49%), and 17.5% had high-positive expression (≥50%). The PD-L1 positive rate was 39.0% in squamous cell carcinomas and 53.6% in adenocarcinomas. PD-L1 expression was higher in squamous cell carcinomas (P < .001) and lower in adenocarcinomas (P < .001). Of the overall patient population, 11.2% had Kirsten rat sarcoma viral oncogene (KRAS) mutations, 44.9% had epidermal growth factor receptor (EGFR) mutations, 2.1% had BRAF V600E mutations, 0.3% had MET exon 14 skipping mutations, 5.4% had anaplastic lymphoma kinase translocations, and 0.9% had ROS proto-oncogene 1 translocations. Patients carrying ROS proto-oncogene 1 translocations (P = .006), KRAS (P < .001), and MET (P = .023) mutations had significantly elevated expression of PD-L1, while those harboring EGFR (P < .001) mutations had lower PD-L1 expression. In our study, PD-L1 expression was significantly higher in squamous cell carcinomas and lower in adenocarcinomas, and was positively associated with MET and KRAS mutations, as well as the wild-type EGFR gene state. Nonetheless, additional studies are needed to further validate those associations and determine the clinical significance for immune checkpoint inhibitors of these factors.

China expert recommendations on anaplastic lymphoma kinase-tyrosine kinase inhibitors treatment for advanced non-small cell lung cancer (2024 edition)

Anaplastic lymphoma kinase (ALK) fusion represents one of pivotal driver genes within the realm of non-small cell lung cancer (NSCLC). ALK-tyrosine kinase inhibitors (ALK-TKI) have demonstrated remarkable therapeutic efficacy for patients afflicted with ALK-positive NSCLC. As of June 27, 2023, seven ALK-TKI, including crizotinib, ceritinib, alectinib, ensartinib, brigatinib, lorlatinib, and iruplinalkib, have garnered approval from the China National Medical Products Administration (NMPA)(ranking according to the approval time for marketing by NMPA), providing individualized treatment modalities for ALK-positive NSCLC patients. To standardize the application of ALK-TKI, the Chinese Association for Clinical Oncologists and the Medical Oncology Branch of China International Exchange and Promotive Association for Medical and Health Care has organized experts to compile the " China expert recommendations on anaplastic lymphoma kinase-tyrosine kinase inhibitors treatment for advanced non-small cell lung cancer (2024 edition)". This treatment expert recommendation provides recommendations in four aspects, encompassing ALK fusion testing, ALK-TKI targeted therapy, ALK-TKI adverse events management, and patient post-treatment follow-up, thus serving as a valuable reference for the standardized treatment of Chinese advanced ALK fusion-positive NSCLC.

Research On Befortinib: Characteristics, Role, And Development of Fourth-Generation EGFR-Tkis

Lung cancer is one of the most common cancers in terms of morbidity and mortality. Among them, non-small cell lung cancer (NSCLC) accounts for 90% of lung cancer patients. Epidermal Growth Factor Receptor (EGFR) mutations are also the most common type of driver gene mutation in advanced NSCLC. In Chinese NSCLC patients, the proportion of EGFR mutations was 28.2%, and this proportion increased to 50.2% in lung adenocarcinoma. All three generations of Epidermal Growth Factor Receptor Tyrosine Kinase Inhibitors (EGFR-TKI) are effective therapeutics for lung cancer patients carrying EGFR-sensitive mutations or T790M mutations, each of which has its own advantages and characteristics, as well as its own limitations and adverse reactions. Befortinib, which is new to the market in 2023, has better Median progression-free survival (mPFS). However, three generations of EGFR-TKI cannot completely overcome the resistance mechanism of lung cancer. In addition to the T790M mutation, there are other mutations or mechanisms that cause lung cancer to become resistant to third-generation EGFR-TKI, such as C797S mutation, MET amplification, HER2 amplification, etc. At present, the fourth-generation of EGFR-TKI is still under continuous research and development.

1238P Detecting driver mutations by AmoyDx 11-gene PCR with high concordance with next-generation sequencing in Chinese non-small cell lung cancer patients

1238P Detecting driver mutations by AmoyDx 11-gene PCR with high concordance with next-generation sequencing in Chinese non-small cell lung cancer patients

Machine Learning Study of SNPs in Noncoding Regions to Predict Non-small Cell Lung Cancer Susceptibility

Non-small cell lung cancer (NSCLC) is the most common pathological subtype of lung cancer. Both environmental and genetic factors have been reported to impact the lung cancer susceptibility. We conducted a genome-wide association study (GWAS) of 287 NSCLC patients and 467 healthy controls in a Chinese population using the Illumina Genome-Wide Asian Screening Array Chip on 712,095 SNPs (single nucleotide polymorphisms). Using logistic regression modeling, GWAS identified 17 new noncoding region SNP loci associated with the NSCLC risk, and the top three (rs80040741, rs9568547, rs6010259) were under a stringent p-value (<3.02e-6). Notably, rs80040741 and rs6010259 were annotated from the intron regions of MUC3A and MLC1, respectively. Together with another five SNPs previously reported in Chinese NSCLC patients and another four covariates (e.g., smoking status, age, low dose CT screening, sex), a predictive model by machine learning methods can separate the NSCLC from healthy controls with an accuracy of 86%. This is the first time to apply machine learning method in predicting the NSCLC susceptibility using both genetic and clinical characteristics. Our findings will provide a promising method in NSCLC early diagnosis and improve our understanding of applying machine learning methods in precision medicine.

Novel insights into molecular patterns of ROS1 fusions in a large Chinese NSCLC cohort: a multicenter study.

ROS proto-oncogene 1, receptor tyrosine kinase (ROS1) rearrangements are a crucial therapeutic target in non-small cell lung cancer (NSCLC). However, there is limited comprehensive analysis of the molecular patterns of ROS1 fusions. This study aimed to address this gap by analysing 135 ROS1 fusions from 134 Chinese NSCLC patients using next-generation sequencing (NGS). The fusions were categorized into common and uncommon based on their incidence. Our study revealed, for the first time, a unique distribution preference of breakpoints within ROS1, with common fusions occurring in introns 31-33 and uncommon fusions occurring in introns 34 and 35. Additionally, we identified previously unknown breakpoints within intron 28 of ROS1. Furthermore, we identified a close association between the distribution patterns of fusion partners and breakpoints on ROS1, providing important insights into the molecular landscape of ROS1 fusions. We also confirmed the presence of inconsistent breakpoints in ROS1 fusions between DNA-based NGS and RNA-based NGS through rigorous validation methods. These inconsistencies were attributed to alternative splicing resulting in out-of-frame or exonic ROS1 fusions. These findings significantly contribute to our understanding of the molecular characteristics of ROS1 fusions, which have implications for panel design and the treatment of NSCLC patients with ROS1 rearrangements.

Molecular profiling and prognostic biomarkers in chinese non-small cell lung cancer cohort

IntroductionComprehensive information about the genome analysis and its prognostic values of NSCLC patients in Chinese population are still needed.PatientsA total of 117 Chinese patients with NSCLC were enrolled in this study. Tumor tissues or blood were collected and sequenced by targeted next-generation sequencing of 556 cancer related genes. The associations between clinical outcomes and clinical characteristics, TMB, mutated genes, treatment therapies were analyzed using Kaplan-Meier methods and further evaluated using multivariable Cox proportional hazards regression model.ResultsA total of 899 mutations were identified by targeted NGS. The most frequently mutations included EGFR (47%), TP53 (46%), KRAS (18%), LRP1B (12%) and SPTA1 (10%). Patients with mutant TP53, PREX2, ARID1A, PTPRT and PIK3CG had lower median overall survival (OS) than those patients with wild-type (P = 0.0056, P < 0.001, P < 0.0001, P < 0.0001 and P = 0.036, respectively). Using a multivariate Cox regression model, PREX2 (P < 0.001), ARID1A (P < 0.001) and PIK3CG (P = 0.04) were independent prognostic factors in NSCLC. In the patients received chemotherapy, squamous patients had a significantly longer median OS than adenocarcinoma patients (P = 0.011). In the patients received targeted therapy, adenocarcinoma patients had a significantly longer survival period than squamous patients (P = 0.01).ConclusionsOur study provided comprehensive genomic alterations in a cohort of Chinese NSCLC. We also identified new prognostic biomarkers, which could provide potential clues for targeted therapies.

A comprehensive pan-cancer analysis of PD-L1 expression using clone E1L3N in Chinese patients with cancer.

2656 Background: Immune checkpoint inhibitors (ICIs) benefit patients with multiple cancer types, and the expression of programmed death ligand 1 (PD-L1) protein assessed by immunohistochemistry (IHC) has been correlated with response and survival benefit from anti-PD-1/PD-L1 ICI therapies in several cancer types. IHC assay with E1L3N clone is currently approved by the NMPA for PD-L1 detection in non-small cell lung cancer (NSCLC), but its performance in other cancer types needs to be further validated. Thus, we performed this study to examine the prevalence of PD-L1 expression in a wide variety of tumor types in Chinese pan-cancer patients using the E1L3N antibody clone. Methods: From 2019 to 2022, a total of 13,647 patient across multiple tumor types were analyzed. Tumor tissue samples were subjected to IHC. PD-L1 expression was tested using the E1L3N PD-L1 IHC assay (Amoy Diagnostics, Xiamen, China), and scored with the tumor proportion score (TPS) and combined positive score (CPS). PD-L1 expression status was identified as positive and negative according to TPS or CPS. For NSCLC: negative (TPS &lt; 1%), low expression (TPS 1-49%), and high expression (TPS ≥ 50%). For gastric/gastroesophageal junction carcinoma (GC/GJC): negative (CPS &lt; 1), low expression (CPS 1-5), and high expression (CPS ≥ 5). For other cancer: negative (CPS &lt; 1), low expression (CPS 1-10), and high expression (CPS ≥ 10). Results: In total, 14 cancer types were enrolled in the present study, including 68.2% NSCLC, 6.9% colorectal carcinoma (CRC), and 3.8% GC/GJC, and the remaining 21.1% include esophageal cancer (EC), breast cancer, cervical cancer (CC), biliary tract cancer (BTC), pancreatic cancer (PC), ovarian cancer, renal cancer, small cell lung cancer, urothelial carcinoma (UC), bladder cancer, head and neck squamous cell carcinoma (HNSCC), etc. PD-L1 positivity by TPS was observed in 52.5% NSCLC patients, similar to the frequency of PD-L1 expression in Chinese NSCLC patients detected using 22C3 clone. 76.0% and 36.7% of GC/GJC patients with PD-L1-positive tumors at a CPS cutoff of ≥ 1 and ≥ 5, respectively. PD-L1 positive expression frequency was higher than that in western GC/GJC patients detected using 22C3 and 28-8 clone (as reported from previous research: PD-L1 positivity with CPS ≥ 1 was 45.5% using the 22C3 assay and 49.1% using the 28-8 assay). 73.6% and 17.5% of CRC patients with PD-L1-positive tumors at a CPS cutoff of ≥ 1 and ≥ 10, respectively. In addition, 8 tumors (EC, CC, breast cancer, PC, BTC, UC, HNSCC, and bladder cancer) had the prevalence of PD-L1 CPS ≥ 1 greater than 50%. Conclusions: E1L3N can be used as a reliable alternative antibody clone to evaluate PD-L1 expression status not only in NSCLC patients but also in other cancer types.

STAT3 and STAT6 polymorphisms predict the severity of adverse reactions in Chinese NSCLC patients receiving EGFR-TKIs therapy

A total of 162 non-small cell lung cancer (NSCLC) patients were divided into discovery (N = 68) and validation (N = 94) groups. Nine Janus kinase/Signal transducer and activator of transcription (JAK/STAT) pathway-related single nucleotide polymorphisms were selected to explore the potential associations between genetic polymorphisms and adverse drug reactions (ADRs). The TT genotype of STAT6 rs324011 was significantly associated with severe ADRs in the recessive genetic model (TT vs. CC + CT, OR = 13.5, 95% CI = 2.12–86.09, p = 0.006 in the discovery group; OR = 8.41, 95% CI = 1.95–36.19, p = 0.004 in the validation group). The T allele was associated with a higher incidence of severe ADRs than was the C allele of rs324011 (OR = 3.67, 95% CI = 1.46–9.19, p = 0.006 in the discovery group; OR = 3.17, 95% CI = 1.44–6.99, p = 0.004 in the validation group). Patients with the CC genotype in STAT3 rs1053023 (and rs1053005) or the TT genotype of STAT6 rs324011 were likely to experience severe epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs) related ADRs.

Genomic profiling of NGS-based ctDNA from Chinese non-small cell lung cancer patients.

Cell-free circulating tumor DNA (ctDNA) in plasma enables rapid and repeat testing of actionable mutations. Next-generation sequencing (NGS) is an attractive platform for multiplex sequencing capabilities compared to traditional methods such as PCR. The purpose of this study is to evaluate the value of the NGS-based ctDNA assay and to identify the genomic alteration profile of ctDNA in real-world Chinese non-small cell lung (NSCLC) patients. In total, 294 Chinese patients with pathological diagnosis of Phase III-IV NSCLC were enrolled. 3-4mL peripheral blood was collected and NGS-based analysis was carried out using a 20-gene panel. The analytical sensitivity and specificity of ctDNA NGS-based assay was validated using droplet digital PCR (ddPCR). We have tested 570 sites from 286 samples using ddPCR, which included 108 positive sites and 462 negative sites from NGS results, and the concordance rate was 99.8% (418/419) for single-nucleotide variants (SNVs) and 96.7% (146/151) for insertions and deletions (InDels). The most frequent genes were TP53 (32%), EGFR (31.97%), KRAS (6.46%), PIK3CA (4.76%), and MET (4.08%). Exon 19 deletion (19del) was the most common alteration in EGFR and G12C was the most common alteration in KRAS. Furthermore, the detection rate of TP53 was higher in the male and patients with squamous cell carcinoma. We also found the prevalence of TP53 in L858R was higher than in 19del (61.29% vs. 40%; p = 0.1115). The results indicate that the results of NGS-based ctDNA assay are highly consistent with ddPCR. In Chinese NSCLC patients, TP53 mutation was more frequently associated with male and squamous cell carcinoma. The prevalence of concomitant mutations in L858R may be different from that in 19del.

Abstract 1403: Comprehensive characterization of 1038 Chinese non-small cell lung cancer patients of different PD-L1 expression levels

Abstract Background: Programmed death ligand 1 (PD-L1) is currently one of the most well-characterized markers for predicting response to immunotherapy in non-small cell lung cancer (NSCLC). Multiple clinicohistologic and genetic characteristics have been proposed as correlates of PD-L1 expression. However, few studies have examined the associations between PD-L1 expression and immune infiltration or chromosomal arm-level alterations. In this comprehensive characterization, we identified clinical features, oncogenic drivers and other genomic abnormalities, impaired biological pathways, arm-level amplifications and losses, and infiltration of immune cell populations that were associated with PD-L1 expression. Methods: We retrospectively included 1038 NSCLC patients who had both PD-L1 Tumor Proportion Score (TPS) by the 22C3 assay and genomic profiles acquired with targeted sequencing using 8-, 168-, and 520-gene panels (Burning Rock Biotech, Guangzhou, China). Multiplex immunohistochemistry (mIHC) was used to analyze immune infiltration. Association analysis was performed to identify patient characteristics associated with PD-L1 expression. Results: The negative (TPS &amp;lt;1%), low (1-49%), and high (≥50%) PD-L1 expression classes accounted for 25.2% (n = 262), 43.2% (n = 449), and 31.5% (n = 327) patients, respectively. PD-L1 expression was positively associated with advanced tumor stage, the male sex, squamous carcinoma, ALK fusions, KRAS G12/13X mutations, BRAF V600E, ROS1 fusion, MET exon 14 skipping, altered TP53, LPR1B, FAT1, PTPRD, KDR, and CD274, and altered pathways such as MAPK, RAS, DNA damage response, p53 signaling, and checkpoint factors. The negative correlates included driver-positive status, EGFR L858R, EGFR exon 19 deletions, ERBB2 exon 20 insertions, altered RMB10, STK11, RICTOR, GNAS, and PIK3C2G, and aberrant receptor tyrosine kinase, ERBB2 signaling, and non-homologous end joining. In terms of arm-level aberrations, PD-L1 positivity was associated with 3p, 3q, 7p or 7q amplification and 18p, 20p, or 20q deletion. We also found that 9p, 9q, 10p, 12p, 12q, and 19p amplifications were most frequent in high PD-L1-high patients, who were also more likely to harbor 18p, 29p, or 20q deletion when compared with compared with PD-L1-negative patients. mIHC analysis revealed that PD-L1 expression was associated with proportions of CD3+, CD3+CD8+, CD3+PD-1+, CD8+PD-1+, and PD-1+ cells in the tumor and CD3+PD-1+, CD8+PD-1+, and PD-1+ cells in the stroma, suggesting increased tumor infiltration of cytotoxic T cells associated with PD-L1 expression. Conclusions: This study provides a comprehensive analysis of the associations between PD-L1 expression and a multitude of histopathologic, genomic, and immunologic features. Further research is warranted for validation and association of these factors with clinical outcomes. Citation Format: Weiqiang Yin, Jinghao Liang, Zhihua Guo, Zixian Xie, Haonan Zhao, Fayuan Wu. Comprehensive characterization of 1038 Chinese non-small cell lung cancer patients of different PD-L1 expression levels [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 1403.

Abstract 3312: Comparison of risk factors to molecular risk stratification in Chinese early-stage non-squamous non-small cell lung cancer patients

Abstract Background: Improved risk stratification for non-small cell lung cancer (NSCLC) represents a critical unmet need. A Clinical Laboratory Improvement Amendments (CLIA)-certified, 14-gene, quantitative PCR (qPCR)-based expression assay was found to better stratify mortality risk. The association of molecular risk stratification with other clinicopathological, radiomic, and genetic risk factors have not been fully identified, especially in Chinese NSCLC patients (pts). Methods: We newly recruited 102 early-stage non-squamous NSCLC pts who had undergone complete surgical resection. RNA was extracted from tumor tissue specimens and prospective molecular risk stratification by the 14-gene prognostic assay was performed. Gene mutation status and tumor mutational burden (TMB) were evaluated. Histological sections and clinical records were reviewed for canonical prognostic indicators that have been reported to be associated with lung cancer risk. Results: Of the 102 pts, the mean age was 55 years, 66 (64.7%) were female, and 18 (17.7%) had a smoking history. The majority of pts (84, 82.4%) were stage I, with 1 atypical adenomatous hyperplasia (AAH), 6 adenocarcinomas in situ (AIS), 1 stage II, and 2 stage III. 64 pts were deemed low-risk by molecular testing, 24 were intermediate-risk, and 14 were high-risk. The pts of AAH and AIS were all in the low-risk group. The maximum tumor diameter (MTD) in the high-risk group was the highest. There were no significant differences in age, sex, smoking status, pathologic stage, NCCN risk criteria, micropapillary or solid (MP/S) pattern, or the number of lesions between the three groups. The most common driver mutations were EGFR (65%), TP53 (28%), and RBM10 (13%). The molecular risk stratification had a significant association with TP53 (p = 0.013), TP53 loss of function (LOF, p = 0.01), KRAS (p = 0.011), and APC mutation (p = 0.05), but not with EGFR mutation and co-mutational status. TMB in the low-risk pts was significantly lower than in other pts (p = 0.007). The low-risk pts had lower SUVmax (p = 0.076), significantly lower mean CT value (p = 0.023), and mean enhanced CT value (p = 0.005) compared with others. In the NCCN low-risk pts, 25 were molecular low-risk, 12 were intermediate-risk, and 9 were high-risk. The risk stratification showed a significant association with SUVmax, TP53 mutation, and TMB in the NCCN low-risk pts. Pearson correlation showed the molecular risk score was significantly associated with MTD, TMB, SUVmax, mean CT value, mean enhanced CT value, and max CT value. SUVmax showed the strongest correlation with the risk score. Conclusion: The molecular risk stratification by the 14-gene assay was associated with canonical prognostic indicators, like TP53 LOF, TP53, KRAS, APC mutation, TMB, mean CT value, and mean enhanced CT value. Our study provides more evidence of the clinical utility of the qPCR-based prognostic assay. Citation Format: Naixin Liang, Jianchao Xue, Ming Zhao, Bowen Li, Yadong Wang, Zhicheng Huang, Yankai Xia, Ruirui Li, Zhongxing Bing, Zhibo Zheng, Jianpeng Zhang, Bin Wang, Zhe Feng, Xinyu Liu, Haochen Li, Xiaoqing Yu, Yang Song. Comparison of risk factors to molecular risk stratification in Chinese early-stage non-squamous non-small cell lung cancer patients [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 3312.