The relationship between EGFR mutation status and clinic-pathologic features in pulmonary adenocarcinoma

Prognostic implications, genomic and immune characteristics of lung adenocarcinoma with lepidic growth pattern

AIMS

Conflicting data were provided regarding the prognostic impact and genomic features of lung adenocarcinoma (LUAD) with lepidic growth pattern (LP+A). Delineation of the genomic and immune characteristics of LP+A could provide deeper insights into its prognostic implications and treatment determination.

METHODS

We conducted a search of articles in PubMed, EMBASE and the Cochrane Library from inception to January 2024. A domestic cohort consisting of 52 LUAD samples was subjected to whole-exome sequencing as internal validation. Data from The Cancer Genomic Atlas and the Gene Expression Omnibus datasets were obtained to characterise the genomic and immune profiles of LP+A. Pooled HRs and rates were calculated.

RESULTS

The pooled results indicated that lepidic growth pattern was either predominant (0.35, 95% CI 0.22 to 0.56, p<0.01) or minor (HR 0.50, 95% CI 0.36 to 0.70, p<0.01) histological subtype was associated with favourable disease-free survival. Pooled gene mutation rates suggested higher EGFR mutation (0.55, 95% CI 0.46 to 0.64, p<0.01) and lower KRAS mutation (0.14, 95% CI 0.02 to 0.25, p=0.02) in lepidic-predominant LUAD. Lepidic-predominant LUAD had lower tumour mutation burden and pooled positive rate of PD-L1 expression compared with other subtypes. LP+A was characterised by abundance in resting CD4+memory T cells, monocytes and γδ T cells, as well as scarcity of cancer-associated fibroblasts.

CONCLUSIONS

LP+A was a unique histological subtype with a higher EGFR mutation rate, lower tumour mutation burden and immune checkpoint expression levels. Our findings suggested potential benefits from targeted therapy over immunotherapy in LP+A.

Clinical Pathological Characteristics and Prognosis of Multigene Co-Mutations in Elderly Patients With Non-Small Cell Lung Cancer: A Retrospective Analysis

Background

With the development and wide application of next-generation sequencing (NGS), multiple-gene mutations related to lung cancer are detected using this technology. Notably, even multigene concomitant mutations (co-mutations), which occur at a relatively low incidence, can be detected more effectively using NGS. It is well-known that the percentages of non-small cell lung cancer (NSCLC) in the elderly lung cancer population are also gradually increasing, while its prognosis is hard and the quality of long-term survival is poor. This study aimed at investigating the common clinicopathologic features of multigene co-mutations for better evaluating the prognosis of elderly NSCLC patients.

Methods

A total of 464 NSCLC patients were divided into 3 groups according to the types of gene mutation, whose clinical data were retrospectively analyzed.

Results

In total, 38.36% (178/464) of NSCLC patients were in the nonmutation group, 50% in the single-gene mutation group, and 11.64% in the multigene co-mutation group. Nonmutation, single-gene mutation, and co-mutation groups were all prone to occur in male adenocarcinoma patients (P < .05). EGFR gene mutation rates were the highest in the single-gene mutation and co-mutation groups (54.31% and 24.35%). In the co-mutation group, the incidence of EGFR/PIK3CA, LK/KRAS, and EGFR/MET co-mutations was the highest (16.67%, 11.11%, and 7.41%). ALK/HER2/MET, EGFR/HER2/MET, and EGFR/HER2/MET/ROS1 multiple-gene co-mutations were, respectively, found in 1 case, and the multigene co-mutation patients commonly had a worse median progression-free survival (PFS) than that of single-gene mutation (7.13 vs 12.34 months, P = .013).

Conclusion

With the application of NGS, the detectable rates of gene co-mutation are increasingly high in elderly patients with NSCLC, which mainly occurs in male adenocarcinoma patients commonly with poor PFS. It will be critically necessary to conduct multigene detections by NGS for directing targeted therapy of elderly NSCLC patients.

Development and Validation of a Concise Prediction Scoring System for Asian Lung Cancer Patients with EGFR Mutation Before Treatment

Purpose We aimed to determine the epidermal growth factor receptor (EGFR) genetic profile of lung cancer in Asians, and develop and validate a non-invasive prediction scoring system for EGFR mutation before treatment. Methods This was a single-center retrospective cohort study using data of patients with lung cancer who underwent EGFR detection (n = 1450) from December 2014 to October 2020. Independent predictors were filtered using univariate and multivariate logistic regression analyses. According to the weight of each factor, a prediction scoring system for EGFR mutation was constructed. The model was internally validated using bootstrapping techniques and temporally validated using prospectively collected data (n = 210) between November 2020 and June 2021.Results In 1450 patients with lung cancer, 723 single mutations and 51 compound mutations were observed in EGFR. Thirty-nine cases had two or more synchronous gene mutations. We developed a scoring system according to the independent clinical predictors and stratified patients into risk groups according to their scores: low-risk (score <4), moderate-risk (score 4-8), and high-risk (score >8) groups. The C-statistics of the scoring system model was 0.754 (95% CI 0.729-0.778). The factors in the validation group were introduced into the prediction model to test the predictive power of the model. The results showed that the C-statistics was 0.710 (95% CI 0.638-0.782). The Hosmer–Lemeshow goodness-of-fit showed that χ² = 6.733, P = 0.566. Conclusions The scoring system constructed in our study may be a non-invasive tool to initially predict the EGFR mutation status for those who are not available for gene detection in clinical practice.

Predictive value of EGFR mutation in non-small-cell lung cancer patients treated with platinum doublet postoperative chemotherapy

The mutation status of tumor tissue DNA (n = 389) of resected stage II‐III non‐squamous non–small‐cell lung cancer (Ns‐NSCLC) was analyzed using targeted deep sequencing as an exploratory biomarker study (JIPANG‐TR) for the JIPANG study, a randomized phase III study of pemetrexed/cisplatin (Pem/Cis) vs vinorelbine/cisplatin (Vnr/Cis). The TP53 mutation, common EGFR mutations (exon 19 deletion and L858R), and KRAS mutations were frequently detected. The frequency of the EGFR mutation was significant among female patients. Patients with an EGFR mutation‐positive status had a significantly shorter recurrence‐free survival (RFS) time (24 mo vs not reached) (HR, 1.64; 95% CI, 1.22‐2.21; P = .0011 for EGFR mutation status). Multivariable analysis identified both the pathological stage and EGFR mutation status as independent prognostic factors for RFS (HR, 1.78; 95% CI, 1.30‐2.44; P = .0003 for disease stage; and HR, 1.57; 95% CI, 1.15‐2.16; P = .0050 for EGFR mutation status). This study demonstrated that the EGFR mutation has either a poor prognostic or predictive impact on a poor response to postoperative chemotherapy with platinum doublet chemotherapy for stage II‐III Ns‐NSCLC patients. This result supports a role for mandatory molecular diagnosis of early‐stage Ns‐NSCLC for precision oncology and signifies the importance of adjuvant for the 3rd generation tyrosine kinase inhibitor rather than platinum‐based chemotherapy. This study is registered with the UMIN Clinical Trial Registry (UMIN 000012237).