Exon-level TP53 alterations and PD-L1 expression identified by pretreatment NGS stratify survival in EGFR-mutant non-small cell lung cancer treated with first-line osimertinib
Original Article

Exon-level TP53 alterations and PD-L1 expression identified by pretreatment NGS stratify survival in EGFR-mutant non-small cell lung cancer treated with first-line osimertinib

Seong-Eun Kim1# ORCID logo, Yongjae Kim2#, Do Kyung Yoon2, Hwan Park2, Kang-Seo Park1, Deokhoon Kim3, Hee Sang Hwang3, Bokyung Ahn3, Ji Eun Park4, Sang-We Kim1, Se Jin Jang3, Shinkyo Yoon1, Ho-Su Lee2, Dae Ho Lee1

1Department of Oncology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea; 2Department of Biochemistry and Molecular Biology, Asan Medical Center, Brain Korea 21 Project, University of Ulsan College of Medicine, Seoul, Korea; 3Department of Pathology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea; 4Department of Radiology and Research Institute of Radiology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea

Contributions: (I) Conception and design: All authors; (II) Administrative support: S Yoon, HS Lee, DH Lee; (III) Provision of study materials or patients: D Kim, HS Hwang, B Ahn, JE Park, SW Kim, SJ Jang, S Yoon, DH Lee; (IV) Collection and assembly of data: D Kim, HS Hwang, B Ahn, JE Park, SW Kim, SJ Jang, S Yoon, DH Lee; (V) Data analysis and interpretation: SE Kim, Y Kim, DK Yoon, H Park, S Yoon, HS Lee; (VI) Manuscript writing: All authors; (VII) Final approval of manuscript: All authors.

#These authors contributed equally to this work as co-first authors.

Correspondence to: Ho-Su Lee, MD, PhD. Associate Professor, Department of Biochemistry and Molecular Biology, Asan Medical Center, Brain Korea 21 Project, University of Ulsan College of Medicine, 88, Olympic-ro 43-gil, Songpa-gu, Seoul, 05505, Korea. Email: ho-su@amc.seoul.kr; Prof. Dae Ho Lee, MD, PhD. Department of Oncology, Asan Medical Center, University of Ulsan College of Medicine, 88, Olympic-ro 43-gil, Songpa-gu, Seoul 05505, Korea. Email: leedaeho@amc.seoul.kr.

Background: Osimertinib is the standard first-line treatment for non-small cell lung cancer (NSCLC) patients with epidermal growth factor receptor (EGFR) sensitizing mutations. However, the response duration varies among patients, meaning predictive biomarkers are needed. Therefore, this study explores the role of co-occurring genomic alterations in predicting survival outcomes.

Methods: Clinical data were extracted from electronic medical records. We retrospectively analyzed next-generation sequencing (NGS) data for EGFR-mutant NSCLC patients treated with first-line osimertinib treatment.

Results: Among the patients who underwent first-line osimertinib treatment, baseline NGS data were analyzed from treatment-naïve tissue for 48 patients. Alterations in TP53 were the most common co-mutation event (62.5%). Patients with mutations in TP53 exon 5, which encodes a critical region in the DNA-binding domain, exhibited a reduced treatment period [hazard ratio (HR) =7.67; 95% confidence interval (CI): 1.77–33.32; P=0.007] and overall survival (OS) (HR =9.29; 95% CI: 2.06–41.86; P=0.004) compared to EGFR-mutant NSCLC patients possessing the wild-type TP53. In particular, co-expression of programmed death-ligand 1 (PD-L1) with TP53 exon 5 mutation showed worse time to treatment discontinuation (TTD) (HR =9.27; 95% CI: 1.42–60.34; P=0.02) and OS (HR =14.54; 95% CI: 2.03–104.32; P=0.008).

Conclusions: Mutations in TP53 exon 5 are associated with a shorter first-line osimertinib treatment duration and OS. These findings might provide insight into a combination strategy for the first-line treatment of EGFR mutant NSCLC patients or a patient selection strategy for adjuvant osimertinib.

Keywords: Epidermal growth factor; non-small cell lung cancer (NSCLC); osimertinib


Submitted Jul 30, 2025. Accepted for publication Oct 31, 2025. Published online Dec 29, 2025.

doi: 10.21037/tlcr-2025-880


Highlight box

Key findings

TP53 exon 5 alterations were linked to poor clinical outcomes with first-line osimertinib treatment in non-small cell lung cancer (NSCLC). Especially, patients harboring a TP53 exon 5 mutation and programmed death-ligand 1 (PD-L1) 22C3 expression ≥50% exhibited the worst treatment duration and overall survival (OS) compared to those with TP53 wild-type and low PD-L1 expression.

What is known and what is new?

• Despite a significant progression-free survival benefit, duration of response to osimertinib varies among patients, but predictive markers remain unclear.

• This study investigated the application of targeted next-generation sequencing (NGS) in epidermal growth factor receptor (EGFR)-mutant NSCLC patients treated with first-line osimertinib and demonstrated the predictive and prognostic significance of co-mutations on treatment duration of osimertinib and OS.

What is the implication, and what should change now?

• Our analysis further indicates that patients harboring both TP53 exon 5 alterations and PD-L1 expression may experience particularly poor outcomes and may benefit from more intensive combination strategies. The results could help guide combination strategies for first-line treatment in EGFR-mutant NSCLC or inform patient selection for adjuvant osimertinib.


Introduction

Non-small cell lung cancer (NSCLC) remains one of the leading causes of cancer-related deaths. Epidermal growth factor receptor (EGFR)-activating mutations are the most common driver oncogene detected in 30–40% of NSCLC patients (1). Tyrosine kinase inhibitors (TKIs) targeting EGFR sensitizing, T790M, and uncommon EGFR mutations have caused a pivotal change in the treatment landscape of NSCLC (2-4). Indeed, the FLAURA trial, a randomized phase III trial comparing osimertinib and standard first-line EGFR TKIs (erlotinib or gefitinib), demonstrated superior progression-free survival (PFS) and overall survival (OS) benefits following first-line osimertinib treatment (5). Subsequently, osimertinib has become the standard first-line treatment for patients with EGFR-sensitizing mutations. However, despite notable PFS benefits, individual patients have exhibited variable response durations to osimertinib (from 13.8 to 22.0 months) (5). Moreover, predictive biomarkers related to the response duration have yet to be elucidated.

Next-generation sequencing (NGS) in clinical oncology can be implemented to address various co-occurring genetic alterations in patients with documented driver oncogenes. Previous studies have suggested a potential association between TP53 mutations, RB1 mutations, and MDM2 amplification and poor survival outcomes in EGFR mutant NSCLC patients, which was detected by targeted panel sequencing (6,7). However, a comprehensive co-occurring genetic landscape profile in EGFR mutant patients treated with first-line osimertinib remains limited. Hence, this study aimed to investigate the co-occurring genetic alteration profiles assessed by NGS for patients treated using first-line osimertinib and the significance of the duration of response to osimertinib. We present this article in accordance with the REMARK reporting checklist (available at https://tlcr.amegroups.com/article/view/10.21037/tlcr-2025-880/rc).


Methods

Study population and specimens

A total of 48 patients with advanced NSCLC were tested for clinically relevant genes by targeted NGS using tumor tissue samples acquired before administering Osimertinib between 2018 and 2022. Patient information, including sex, age, baseline EGFR mutation types, histological diagnoses, treatment histories, and treatment and survival outcomes, was retrieved from electronic medical records. Time to treatment discontinuation (TTD) and OS were examined. The study was conducted in accordance with the Declaration of Helsinki and its subsequent amendments. This study was conducted retrospectively and was approved by the Institutional Review Board of Asan Medical Center (IRB No. 2020-1204), with informed consent waived due to the retrospective nature.

Targeted NGS

DNA was extracted from previously collected formalin-fixed, paraffin-embedded (FFPE) tissue specimens. To determine the frequency of co-occurring genes in NSCLC patients with EGFR mutations and the predictive effect of co-mutations on the efficacy of osimertinib, genetic sequencing and mutation calling were performed using an in-house panel of the AMC, Seoul, Korea (OncoPanel AMC, versions 3 and 4), as previously described (8,9). The OncoPanel AMC version 3 (OP AMC v3) and version 4 (OP AMC v4) were conducted using the MiSeq platform (Illumina, San Diego, CA, USA) and captured 383 and 322 cancer-related genes, respectively (OP AMC v3: 199 genes for entire exons, 8 genes for partial introns, and 184 genes for hotspots; OP AMC v4: 225 genes for entire exons, 6 genes for partial introns, and 99 for hotspots).

The sequence mapping steps for OP AMC v3 and v4 were performed in accordance with a previously described method (10,11). Somatic variant calling for single-nucleotide variants and short indels was conducted using VarDict (12). Germline variants in candidates relating to somatic variants (found in ≥1% of samples) were filtered out using a common germline variants database (dbSNP build 141, gnomAD; common germline variants from 1,100 healthy Korean participants) (13). The normal panel was also used for variant calling. Tumor mutational burden (TMB) was calculated as the number of nonsynonymous alterations per megabase (Mb) in the examined genome.

Immunohistochemistry (IHC)

For the programmed death-ligand 1 (PD-L1) assay, FFPE tissue sections (4 µm thick) were dried at 60 ℃ for 30 minutes. The PharmDx assay (Dako, Carpinteria, CA, USA) involved staining using an anti-PD-L1 22C3 mouse monoclonal primary antibody. For the mesenchymal-epithelial transition factor (MET) assay, the 4 µm thick FFPE tissue sections were deparaffinized and rehydrated, and antigen retrieval was performed in citrate buffer (pH 6.1) at 95 ℃ for 40 minutes. The CONFIRM anti-total c-MET SP44 antibody (Ventana Medical Systems) was used for MET IHC staining. IHC data were categorized according to the following staining scores: 0, negative (no staining, or <50% of the tumor cells with any intensity); 1, weak (≥50% of the tumor cells with weak or higher staining, but <50% with moderate or higher intensity); 2, moderate (≥50% of the tumor cells with moderate or higher staining, but <50% with strong intensity); 3, strong (≥50% of the tumor cells staining with strong intensity) (14).

cBioPortal (RRID:SCR_014555) database analysis

Information regarding TP53 and EGFR alterations, the survival time, and live/dead status at the 5-year follow-up in NSCLC patients was downloaded from the cBioPortal (RRID:SCR_014555) using the cgdsr package (version 1.3.0) (15,16). The Memorial Sloan Kettering Cancer Center - Integrated Mutation Profiling of Actionable Cancer Targets (MSKCC-IMPACT) 2021 (17), Oncology Singapore (OncoSG) (18), The Cancer Genome Atlas (TCGA) (19), and National Cancer Institute (NCI) (20) datasets were selected. Among a total of 1,196 NSCLC samples, we identified 579 samples derived from 379 patients harboring EGFR mutations. For survival analysis, we excluded patients with mutations affecting multiple TP53 exons or those lacking either OS duration or survival status data. Consequently, a total of 359 EGFR-mutated patients were analyzed.

Statistical analysis

The Fisher’s exact test, or Wilcoxon rank-sum test, was performed as appropriate. TTD was defined as the date of osimertinib treatment started and the date of treatment discontinuation or death from any cause. OS was defined as the time from the start of osimertinib treatment to death from any cause. TTD and OS were evaluated using Kaplan-Meier methods and compared using the log-rank test. For analyses involving biomarkers with missing data (PD-L1 and MET IHC), patients were excluded only from the specific analyses requiring those markers but were included in all other analyses. Missing data were handled using complete-case analysis for each specific comparison. Multivariable Cox regression analyses were not performed due to the limited sample size and low number of events, which would risk model overfitting and unreliable estimates. Stratified analyses were conducted to examine the combined effects of TP53 mutations and PD-L1 expression. A P value <0.05 was considered statistically significant, and R (version 4.1.0) was used for all statistical analyses.


Results

Patient characteristics

We retrospectively identified 48 patients with EGFR-mutated NSCLC whose pretreatment tumors had been assessed using targeted gene panel NGS and who had undergone first-line osimertinib treatment for recurrent or initially metastatic lung adenocarcinoma between 2018 and 2022 (Table 1). Among these 48 patients, 22 (45.8%) were male, 34 (70.8%) were non-smokers, and osimertinib treatment was initiated at a median age of 62 years. At the time of data cutoff (31 March 2022), 14 (29.2%) patients had died; the median follow-up was 19.7 months. The median duration of osimertinib treatment was 11.1 months (range, 0.9–38.7 months). Detailed clinicopathological characteristics are shown in Table 1.

Table 1

Baseline characteristics of all included patients

Characteristics Values (n=48)
Demographics
   Age, years 62 [35–81]
   Sex
    Male 22 (45.8)
    Female 26 (54.2)
   Smoking status
    Never smoker 34 (70.8)
    Smoker 14 (29.2)
   ECOG
    0 4 (8.3)
    1 30 (62.5)
    2 5 (10.4)
    3 5 (10.4)
    4 1 (2.1)
    Unknown 3 (6.3)
Disease status
   Stage
    I 8 (16.7)
    II 1 (2.1)
    IV 38 (79.2)
    Unknown 1 (2.1)
   Brain metastasis
    Yes 17 (35.4)
    No 31 (64.6)
Molecular features
   EGFR mutation type
    L858R 23 (47.9)
    Exon 19 deletion 22 (45.8)
    Other 3 (6.3)
   Tumor mutational burden, mut/Mb 12.5 [3.1–25.0]
Biomarker
   PD-L1 tumor proportion score
    <1% 14 (29.2)
    ≥1% 28 (58.3)
    1–49% 23 (47.9)
    ≥50% 5 (10.4)
    Not done 6 (12.5)
   MET immunohistochemistry
    <3 18 (37.5)
    3 8 (16.7)
    Not done 22 (45.8)

Data are presented as median [range] or n (%). ECOG, Eastern Cooperative Oncology Group; EGFR, epidermal growth factor receptor; IHC, immunohistochemistry; Mb, megabase; MET, mesenchymal-epithelial transition factor; PD-L1, programmed death-ligand 1.

Landscape of genomic alterations

Regarding the founder EGFR mutation, 23 patients (47.9%) possessed the L858R point mutation, 22 (45.8%) patients harbored an exon 19 deletion, and three patients carried atypical mutations, such as L861Q, G719A/T790M, and L694_T698delinsQ/K754E (Figure 1 and Figure S1). T790M mutations that occurred de novo were detected in four patients: two patients with the L858R mutation, one patient with the exon 19 deletion, and one patient with the G719A mutation. A comparison was performed between the patients with the exon 19 deletion and those with the L858R mutation and identified a numerical trend that favored the exon 19 deletion compared with the L858R mutation in the TTD and OS {TTD: HR =2.31 [95% confidence interval (CI): 0.69–7.70]; P=0.17; OS: HR =2.39 (95% CI: 0.72–7.94); P=0.16} (Figure S2A,S2B).

Figure 1 Classification of EGFR driver mutations. del, deletion; EGFR, epidermal growth factor receptor; indel, insertion–deletion.

In total, 47 patients (47/48, 97.9%) were found to have co-occurring genetic alterations (Figure 2). The median TMB was 12.5 mutations/Mb (range, 3.1–25.0 mutations/Mb). The most common co-mutated genes were TP53 (62.5%, 30/48), ATM (16.7%, 8/48), FLT1 (16.7%, 8/48), SLX4 (12.5%, 6/48), CTNNB1 (12.5%, 6/48), and BARD1 (12.5%, 6/48). A total of 31 TP53 alterations in 30 patients were evaluated in parallel with data analysis from TCGA database (21,22). In total, 26 mutations were identified in TP53 that affected the DNA-binding domain, and two mutations affected the proline-rich domain. Additionally, one truncating mutation (Q317*) and two splicing mutations (c.560-1G>T and c.920-1G>T) were observed (Figure 3). Baseline brain metastasis was present in 17 patients (35.4%), and the frequency of TP53 mutations (76.5% vs. 54.8%, P=0.21) and TP53 exon 5 mutations (35.3% vs. 9.7%, P=0.051) did not differ significantly between patients with and without brain metastasis. Among the four patients who had a post-treatment biopsy, one had the C797S mutation in the post-osimertinib specimens. The evident on-target or off-target resistance profiles were not identified in the remaining three patients.

Figure 2 Mutation spectrum and landscape. The plot was created using the JavaScript library jsComut (https://github.com/pearcetm/jscomut; last accessed September 2022). IHC, immunohistochemistry; MET, mesenchymal-epithelial transition factor; MT, mutant type; PD-L1, programmed death-ligand 1; TMB, tumor mutational burden; TTD, time to treatment discontinuation; WT, wild-type.
Figure 3 Mutation maps of TP53 protein. A lollipop plot of the variants found in the TP53 gene. CTD, carboxy-terminal domain; DBD, DNA-binding domain; del, deletion; fs, frameshift; OD, oligomerization domain; PR, proline-rich domain; TA, transactivation domain.

Of the 48 patients, 6 patients had insufficient tissue samples for the PD-L1 assay, 28 (28/41, 68.3%) showed PD-L1 ≥1%, and 14 (14/41, 34.1%) had PD-L1 negative tumors. Furthermore, 5 of the 28 patients with PD-L1 ≥1% were strongly positive for PD-L1 (≥50%). In the MET IHC analysis, 22 patients had insufficient tissue for MET IHC, eight patients (8/25, 32.0%) were MET IHC 3+, and 18 patients (18/25, 72%) were MET IHC 0–2+ (Table 1). Analysis of NGS data revealed MET gene amplification in 3 patients (6.3%) at baseline. There was poor concordance between MET amplification detected by NGS and MET protein overexpression detected by IHC (concordance rate: 12.5%, 1 out of 8 MET IHC 3+ cases showed amplification).

Predictive and prognostic value of TP53 co-mutation and other genomic alterations

Analysis of pre-osimertinib alterations associated with TTD and OS revealed a trend towards worse outcomes in patients with TP53 alterations (Figure 4A,4B). Given that different types of TP53 genetic mutations tend to have different effects on the functionality of the protein (7,21-25), we classified TP53 mutations in other sites. The various TP53 mutations detected in our study and their distribution are shown in Figure 3 and Table S1. We speculated that mutations on different TP53 exons might show distinct prognostic or predictive effects (21,23,26,27); each mutation was analyzed separately according to the exon. TP53 exon 5 mutations (18.8%, 9/48) showed an association with a shorter TTD when compared with TP53 wild-type (WT) controls (HR =7.67; 95% CI: 1.77–33.32; P=0.007; Figure 4C). Other TP53 exon mutations (including exons 4, 6, 7, 8, and 9; n=21, 43.8%) did not show significant associations with TTD compared to TP53 WT (HR =1.87; 95% CI: 0.47–7.48; P=0.38; Figure 4C). Similarly, in the prognostic analysis, we found that TP53 exon 5 mutations were significantly associated with poor survival (HR =9.29; 95% CI: 2.06–41.86; P=0.004; Figure 4D), while other TP53 exon mutations showed no significant association with OS (HR =1.63; 95% CI: 0.41–6.60; P=0.49; Figure 4D).

Figure 4 Association between TP53 alterations and clinical outcomes in patients treated with osimertinib. (A,B) Kaplan-Meier curves of the TTD and OS, respectively, stratified by TP53 co-alteration status. (C,D) TTD and OS were stratified by TP53 exon 5 alteration status. (E,F) TTD and OS were stratified by combined TP53 exon 5 alteration and PD-L1 expression statuses. HRs, 95% CIs, P values, and median survival ranges (months) are provided in the tables below each plot. CI, confidence interval; HR, hazard ratio; m, months; MT, mutant type; NA, not applicable; OS, overall survival; PD-L1, programmed death-ligand 1; TTD, time to treatment discontinuation; WT, wild-type.

We next sought to understand how TP53 alterations promote resistance by evaluating whether TP53 alterations are associated with specific mutagenesis patterns or increased genomic instability, as these processes might act as potential mechanisms in osimertinib resistance. The TTD for patients with TP53 exon 5 mutations and PD-L1 expression remained on osimertinib treatment for a significantly shorter time than for those without TP53 exon 5 mutations and PD-L1 expression (HR =9.27; 95% CI: 1.42–60.34; P=0.02; Figure 4E). Furthermore, patients with TP53 exon 5 mutations and elevated PD-L1 expression showed a significantly reduced OS compared to those lacking these mutations and PD-L1 expression (HR =14.54; 95% CI: 2.03–104.32; P=0.008; Figure 4F). Predictive and prognostic values of various alterations were also analyzed, including MET overexpression, TMB status and PD-L1. As demonstrated in Figure S3, MET overexpression, TMB and PD-L1 expression alone did not exhibit significant predictive and prognostic values.

Validation of clinical value of TP53 exon 5 co-mutations in patients with EGFR mutations

We analyzed a publicly available database to validate the prognostic value of TP53 exon 5 mutations identified from the current analysis in independent cohorts. NSCLC sequencing and clinical metadata from four cohorts were obtained from cBioPortal (15,16), MSKCC-IMPACT 2021 (17), OncoSG (18), TCGA (19), and NCI (20). Among 359 NSCLC patients with a mutation in EGFR, TP53 mutations were discovered in 49.6% (178/359) of the patients, of which 41.8% (150/359) possessed mutations in the DNA-binding domain (exons 5–8). Thus, based on the data collected from these four cohorts, mutations in TP53 presented poor prognostic value (HR =2.20; 95% CI: 1.54–3.13; P<0.001; Figure 5A). Then, we subdivided TP53 mutations into exons. The common TP53 mutation site was in exon 5, accounting for about 13.1% (47/359) of the observed mutations. Consistent with our findings, the patients with the TP53 exon 5 mutations had the worst 5-year survival compared with those possessing the WT TP53 (HR =3.18; 95% CI: 1.97–5.12; P<0.001; Figure 5B).

Figure 5 The Kaplan-Meier survival analysis for TP53 alteration using cBioPortal data: MSKCC-IMPACT 2021 (n=90), OncoSG (n=143), TCGA (n=66), and NCI (n=60). (A) OS by TP53 status. (B) OS stratified by TP53 exon 5 alteration status. HRs, 95% CIs, P values, and median survival times (months) are shown in the tables below each plot. CI, confidence interval; HR, hazard ratio; MSKCC-IMPACT, Memorial Sloan Kettering Cancer Center - Integrated Mutation Profiling of Actionable Cancer Targets; m, months; MT, mutant type; NA, not applicable; NCI, National Cancer Institute; OncoSG, Oncology Singapore; OS, overall survival; TCGA, The Cancer Genome Atlas; WT, wild-type.

Discussion

We explored the use of targeted NGS in NSCLC patients with EGFR mutations who had received first-line osimertinib treatment in a clinical setting. TP53 co-mutations were the most commonly associated finding with inferior TTD and OS in contrast to TP53 WT in EGFR-mutant NSCLC patients; in particular, mutations in exon 5 of the TP53 gene, which encodes a critical region of the DNA-binding domain. In addition, patients with a TP53 exon 5 mutation and PD-L1 22C3 ≥50% showed the worst TTD and OS compared with TP53 WT and low PD-L1 expression. Considering that first-line osimertinib is the standard treatment in patients with EGFR mutants and NGS is an essential test in stage IV NSCLC patients, our results suggest that TP53 exon 5 mutations alone or in combination with PD-L1 expression might be a stratifying risk factor for predicting the response and survival durations.

TP53 alterations have been suggested to contribute to poor outcomes in EGFR TKI-treated patients (6,23-25,28-31). Although an underlying prognostic effect cannot be excluded, we observed the poor predictive effects of TP53 exon 5 alterations, whereby TP53 exon 5 alterations were associated with decreased TTD. Concurrent TP53 exon 5 mutations may alter clinical outcomes; however, the mechanism through which TP53 mutations are associated with worse outcomes remains largely unknown. We observed that TP53 alterations were associated with increased TMB (mean: 14.01 vs. 10.15; Wilcoxon: P=0.006; Figure S4A), suggesting increased genomic instability. Exon-level analysis demonstrated that TP53 exon 5 mutations were associated with a greater increase in TMB compared with mutations in other TP53 exons (Figure S4B). Overall, tumors with concomitant mutations in EGFR and TP53 may bypass EGFR as a target and activate alternative pathways. Thus, there is a need for combination therapeutic strategies to prolong the duration of initial benefit from EGFR-targeted therapy. Further studies are needed to determine whether comprehensive co-occurring profiling adds clinically relevant information to patients treated with osimertinib.

The varied prognostic effects of TP53 mutations in NSCLC patients have also been reported previously (7), and those conflicting findings were probably due to the heterogeneity of TP53. Moreover, findings remain ambiguous as to whether co-mutations in exon levels within the TP53 gene, and the observed consequences of these mutations are associated with the clinical outcomes. In contrast to previous reports of poor clinical outcomes for mutations in exon 8 of TP53 (21,32-34), no associations between TP53 exon 8 alterations and outcome were observed (Figure S5A,S5B). Instead, consistent with Liu et al. (27), we observed that TP53 mutations in exon 5 were associated with a worse outcome than those in TP53 WT. To validate these findings, we further explored the association of exon-level events with OS using data from the cBioPortal database (n=359). In this larger independent cohort, alterations in DNA-binding domain exons (exons 5–8, analyzed collectively) showed reduced OS compared to TP53 WT (Figure 5A). Among the modifications in exon 5–8 (Figure 5A,5B), Importantly, among DNA-binding domain mutations, alterations in exon 5, presented the worse outcomes (HR =3.18; 95% CI: 1.97–5.12; P<0.001, Figure 5B), suggesting a possible relationship between TP53 exon 5 alterations and outcome (Figures 4C,4D,5A,5B). Particularly, we observed that a combination of TP53 exon 5 alterations and PD-L1 expression was associated with decreased TTD and OS (Figure 4E,4F). Given the potential impacts of specific TP53 alterations on the osimertinib therapeutic response, future studies are needed to determine the effect of exon-level mutations on the outcomes of patients. Also, functional studies investigating the molecular mechanisms by which TP53 exon 5 mutations confer resistance to osimertinib would provide valuable insights for developing combination therapeutic strategies targeting these specific alterations. Although pretreatment PD-L1 expression and MET overexpression per se did not provide any predictive value in patients with EGFR mutants treated using osimertinib, their potential as predictive biomarkers warrants renewed focus in the era of first-line osimertinib therapy. Previous literature has also reported that PD-L1 expression did not affect the osimertinib treatment outcome (35). However, this study did not consider the impact of PD-L1 expression in the context of coexisting genetic alterations, nor did it stratify patients based on strong PD-L1 expression (≥50%). Other studies have demonstrated that high PD-L1 expression is associated with poor outcomes in patients treated with EGFR-TKIs (36-38), including osimertinib (39). Furthermore, a strong association between high PD-L1 expression and TP53 mutations has been reported (40,41). In this study, while PD-L1 expression alone did not significantly impact treatment outcomes, the coexistence of a TP53 mutation and high PD-L1 expression was associated with worse TTD and OS. These findings suggest that patients harboring both TP53 mutations and high PD-L1 expression may represent a subgroup with suboptimal PFS, underscoring the need for alternative therapeutic strategies in the context of EGFR-sensitizing mutations. Moreover, secondary EGFR mutations, such as C797X and G724S—“on-target resistance”—were commonly acquired resistance mechanisms of second-line osimertinib treatment, which was administered only to patients with an acquired EGFR T790M mutation. In contrast, “off-target resistance” accounts for up to 30–50% of cases in which first-line osimertinib was administered. Among off-target resistance, MET amplification is the most common mechanism (42). With the TATTON trial and the upcoming interim analysis of the SAFFRON trial, combining osimertinib and MET targeting agents can be considered a treatment option for patients who experienced disease progression following the first-line osimertinib treatment (43). In the TATTON trial, the combination treatment of savolitinib and osimertinib demonstrated meaningful antitumor activity in patients with EGFR mutants, MET-amplified, or overexpressed NSCLCs that had progressed after prior EGFR-TKI therapy, showing objective response rates up to 67% and a median PFS of up to 11.1 months.

Our study highlights the additional prognostic value of NGS beyond solely performing PCR analysis for EGFR, even when EGFR activating mutations are identified through PCR. A secondary analysis from the MARIPOSA trial demonstrated that TP53 mutations were associated with worse PFS. However, amivantamab treatment in combination with lazertinib significantly improved PFS compared to osimertinb (HR =0.72; 95% CI: 0.58–0.90; P=0.004). These findings suggest that NGS results provide further benefits in guiding treatment decisions (44). Furthermore, upfront platinum combination therapy could be a viable consideration for patients with EGFR and TP53 co-mutations, as explored by FLAURA2. Recently, FLAURA2 showed that the addition of a platinum-pemetrexed alongside osimertinib treatment promoted significantly increased PFS than osimertinib alone (HR for disease progression or death =0.62; 95% CI: 0.49–0.79; P<0.001) (45). Notably, following the FLAURA2 results, the FDA approved osimertinib treatment in combination with platinum-pemetrexed; however, the clinical question of who would benefit from adding intravenous chemotherapy every three weeks will be raised. Furthermore, given that adjuvant osimertinib treatment for patients with an EGFR-sensitizing mutation has become the standard of care based on the ADAURA trial, post-hoc analyses or real-world evidence studies are necessary to evaluate the predictive value of TP53 mutations in this setting.

These findings should be interpreted in the context of the study’s exploratory nature and potential limitations. First, we retrospectively extracted patient-level data. The clinical status of enrolled patients was heterogeneous, and the results of this study may have limited generalizability to all patients. Second, the small sample size precluded drawing firm conclusions. Given that PCR analysis is widely used in routine molecular diagnostics in NSCLC and that additional NGS is rarely implemented when activating mutations are confirmed by EGFR PCR, a pragmatic number of patients was included in this study Also, patients were selected from a consecutive cohort of EGFR-mutant NSCLC patients who received NGS testing at our center, thereby minimizing potential selection bias. Additionally, considering the turnaround time for NGS results is typically 4 to 6 weeks, prospectively collecting a comparable number of NGS data in patients with EGFR mutations is likely to remain challenging. Third, the relatively small sample size and limited number of events precluded us from performing multivariable analyses, which made it challenging to fully adjust for potential confounders. However, to mitigate this limitation, we provided stratified analyses examining the combined impact of TP53 mutations and PD-L1 expression, and validated our findings in independent, publicly available cohorts with larger sample sizes.


Conclusions

In conclusion, TP53 exon 5 alterations were associated with poor clinical outcomes of first-line osimertinib treatment of NSCLC. Our analyses further suggest that the patients possessing combined TP53 exon 5 alterations and PD-L1 expression may result in highly unfavorable outcomes and require intensified combination strategies. Additional studies with larger sample sizes are essential to validate these findings.


Acknowledgments

None.


Footnote

Reporting Checklist: The authors have completed the REMARK reporting checklist. Available at https://tlcr.amegroups.com/article/view/10.21037/tlcr-2025-880/rc

Data Sharing Statement: Available at https://tlcr.amegroups.com/article/view/10.21037/tlcr-2025-880/dss

Peer Review File: Available at https://tlcr.amegroups.com/article/view/10.21037/tlcr-2025-880/prf

Funding: This study was supported by a grant from the Asan Institute for Life Sciences, Asan Medical Center, Seoul, Korea (No. 2022IP0861 to S.Y.). This study was also supported by a grant from the National Research Foundation of Korea (No. NRF-RS-2023-00211481 to H.S.L.), funded by the Ministry of Science and ICT, the Republic of Korea.

Conflicts of Interest: All authors have completed the ICMJE uniform disclosure form (available at https://tlcr.amegroups.com/article/view/10.21037/tlcr-2025-880/coif). S.Y. reports that this study was supported by a grant from the Asan Institute for Life Sciences, Asan Medical Center, Seoul, Korea (No. 2022IP0861). H.S.L. reports that this study was supported by a grant from the National Research Foundation of Korea (No. NRF-RS-2023-00211481), funded by the Ministry of Science and ICT, the Republic of Korea. D.H.L. received consulting fees from Abion, STCube; received payment or honoraria for lectures, presentations, speakers bureaus, manuscript writing or educational events from AstraZeneca/MedImmune, Lilly, Boehringer Ingelheim, MSD, Bristol-Myers Squibb, Novartis, Ono Pharmaceutical, Pfizer, Roche/Genentech, Takeda, Abbvie, Yuhan and Janssen; and received support for attending meetings and/or travel from Abion. The other authors have no conflicts of interest to declare.

Ethical Statement: The authors are accountable for all aspects of the work in ensuring that questions related to the accuracy or integrity of any part of the work are appropriately investigated and resolved. The study was conducted in accordance with the Declaration of Helsinki and its subsequent amendments. The study was approved by the Institutional Review Board of Asan Medical Center (IRB No. 2020-1204), with informed consent waived due to the retrospective nature.

Open Access Statement: This is an Open Access article distributed in accordance with the Creative Commons Attribution-NonCommercial-NoDerivs 4.0 International License (CC BY-NC-ND 4.0), which permits the non-commercial replication and distribution of the article with the strict proviso that no changes or edits are made and the original work is properly cited (including links to both the formal publication through the relevant DOI and the license). See: https://creativecommons.org/licenses/by-nc-nd/4.0/.


References

  1. Passaro A, Leighl N, Blackhall F, et al. ESMO expert consensus statements on the management of EGFR mutant non-small-cell lung cancer. Ann Oncol 2022;33:466-87. [Crossref] [PubMed]
  2. Mok TS, Wu YL, Thongprasert S, et al. Gefitinib or carboplatin-paclitaxel in pulmonary adenocarcinoma. N Engl J Med 2009;361:947-57. [Crossref] [PubMed]
  3. Mok TS, Wu YL, Ahn MJ, et al. Osimertinib or Platinum-Pemetrexed in EGFR T790M-Positive Lung Cancer. N Engl J Med 2017;376:629-40. [Crossref] [PubMed]
  4. Yang JC, Sequist LV, Geater SL, et al. Clinical activity of afatinib in patients with advanced non-small-cell lung cancer harbouring uncommon EGFR mutations: a combined post-hoc analysis of LUX-Lung 2, LUX-Lung 3, and LUX-Lung 6. Lancet Oncol 2015;16:830-8. [Crossref] [PubMed]
  5. Soria JC, Ohe Y, Vansteenkiste J, et al. Osimertinib in Untreated EGFR-Mutated Advanced Non-Small-Cell Lung Cancer. N Engl J Med 2018;378:113-25. [Crossref] [PubMed]
  6. Kim Y, Lee B, Shim JH, et al. Concurrent Genetic Alterations Predict the Progression to Target Therapy in EGFR-Mutated Advanced NSCLC. J Thorac Oncol 2019;14:193-202. [Crossref] [PubMed]
  7. Scoccianti C, Vesin A, Martel G, et al. Prognostic value of TP53, KRAS and EGFR mutations in nonsmall cell lung cancer: the EUELC cohort. Eur Respir J 2012;40:177-84. [Crossref] [PubMed]
  8. Lee K, Kim D, Yoon S, et al. Exploring the resistance mechanisms of second-line osimertinib and their prognostic implications using next-generation sequencing in patients with non-small-cell lung cancer. Eur J Cancer 2021;148:202-10. [Crossref] [PubMed]
  9. Chae H, Kim D, Yoo C, et al. Therapeutic relevance of targeted sequencing in management of patients with advanced biliary tract cancer: DNA damage repair gene mutations as a predictive biomarker. Eur J Cancer 2019;120:31-9. [Crossref] [PubMed]
  10. Kim JE, Chun SM, Hong YS, et al. Mutation Burden and I Index for Detection of Microsatellite Instability in Colorectal Cancer by Targeted Next-Generation Sequencing. J Mol Diagn 2019;21:241-50. [Crossref] [PubMed]
  11. Hwang JA, Kim D, Chun SM, et al. Genomic profiles of lung cancer associated with idiopathic pulmonary fibrosis. J Pathol 2018;244:25-35. [Crossref] [PubMed]
  12. Lai Z, Markovets A, Ahdesmaki M, et al. VarDict: a novel and versatile variant caller for next-generation sequencing in cancer research. Nucleic Acids Res 2016;44:e108. [Crossref] [PubMed]
  13. Sherry ST, Ward MH, Kholodov M, et al. dbSNP: the NCBI database of genetic variation. Nucleic Acids Res 2001;29:308-11. [Crossref] [PubMed]
  14. Spigel DR, Ervin TJ, Ramlau RA, et al. Randomized phase II trial of Onartuzumab in combination with erlotinib in patients with advanced non-small-cell lung cancer. J Clin Oncol 2013;31:4105-14. [Crossref] [PubMed]
  15. Cerami E, Gao J, Dogrusoz U, et al. The cBio cancer genomics portal: an open platform for exploring multidimensional cancer genomics data. Cancer Discov 2012;2:401-4. [Crossref] [PubMed]
  16. Gao J, Aksoy BA, Dogrusoz U, et al. Integrative analysis of complex cancer genomics and clinical profiles using the cBioPortal. Sci Signal 2013;6:pl1. [Crossref] [PubMed]
  17. Cheng DT, Mitchell TN, Zehir A, et al. Memorial Sloan Kettering-Integrated Mutation Profiling of Actionable Cancer Targets (MSK-IMPACT): A Hybridization Capture-Based Next-Generation Sequencing Clinical Assay for Solid Tumor Molecular Oncology. J Mol Diagn 2015;17:251-64. [Crossref] [PubMed]
  18. Chen J, Yang H, Teo ASM, et al. Genomic landscape of lung adenocarcinoma in East Asians. Nat Genet 2020;52:177-86. [Crossref] [PubMed]
  19. Weinstein JN, Collisson EA, et al. The Cancer Genome Atlas Pan-Cancer analysis project. Nat Genet 2013;45:1113-20. [Crossref] [PubMed]
  20. Zhang T, Joubert P, Ansari-Pour N, et al. Genomic and evolutionary classification of lung cancer in never smokers. Nat Genet 2021;53:1348-59. [Crossref] [PubMed]
  21. Canale M, Andrikou K, Priano I, et al. The Role of TP53 Mutations in EGFR-Mutated Non-Small-Cell Lung Cancer: Clinical Significance and Implications for Therapy. Cancers (Basel) 2022;14:1143. [Crossref] [PubMed]
  22. Jiao XD, Qin BD, You P, et al. The prognostic value of TP53 and its correlation with EGFR mutation in advanced non-small cell lung cancer, an analysis based on cBioPortal data base. Lung Cancer 2018;123:70-5. [Crossref] [PubMed]
  23. Molina-Vila MA, Bertran-Alamillo J, Gascó A, et al. Nondisruptive p53 mutations are associated with shorter survival in patients with advanced non-small cell lung cancer. Clin Cancer Res 2014;20:4647-59. [Crossref] [PubMed]
  24. Canale M, Petracci E, Delmonte A, et al. Impact of TP53 Mutations on Outcome in EGFR-Mutated Patients Treated with First-Line Tyrosine Kinase Inhibitors. Clin Cancer Res 2017;23:2195-202. [Crossref] [PubMed]
  25. Labbé C, Cabanero M, Korpanty GJ, et al. Prognostic and predictive effects of TP53 co-mutation in patients with EGFR-mutated non-small cell lung cancer (NSCLC). Lung Cancer 2017;111:23-9. [Crossref] [PubMed]
  26. Hou H, Qin K, Liang Y, et al. Concurrent TP53 mutations predict poor outcomes of EGFR-TKI treatments in Chinese patients with advanced NSCLC. Cancer Manag Res 2019;11:5665-75. [Crossref] [PubMed]
  27. Liu SY, Bao H, Wang Q, et al. Genomic signatures define three subtypes of EGFR-mutant stage II-III non-small-cell lung cancer with distinct adjuvant therapy outcomes. Nat Commun 2021;12:6450. [Crossref] [PubMed]
  28. VanderLaan PA, Rangachari D, Mockus SM, et al. Mutations in TP53, PIK3CA, PTEN and other genes in EGFR mutated lung cancers: Correlation with clinical outcomes. Lung Cancer 2017;106:17-21. [Crossref] [PubMed]
  29. Yu HA, Suzawa K, Jordan E, et al. Concurrent Alterations in EGFR-Mutant Lung Cancers Associated with Resistance to EGFR Kinase Inhibitors and Characterization of MTOR as a Mediator of Resistance. Clin Cancer Res 2018;24:3108-18. [Crossref] [PubMed]
  30. Tsui DWY, Murtaza M, Wong ASC, et al. Dynamics of multiple resistance mechanisms in plasma DNA during EGFR-targeted therapies in non-small cell lung cancer. EMBO Mol Med 2018;10:e7945. [Crossref] [PubMed]
  31. Vokes NI, Chambers E, Nguyen T, et al. Concurrent TP53 Mutations Facilitate Resistance Evolution in EGFR-Mutant Lung Adenocarcinoma. J Thorac Oncol 2022;17:779-92. [Crossref] [PubMed]
  32. Ma X, Rousseau V, Sun H, et al. Significance of TP53 mutations as predictive markers of adjuvant cisplatin-based chemotherapy in completely resected non-small-cell lung cancer. Mol Oncol 2014;8:555-64. [Crossref] [PubMed]
  33. Ma X, Le Teuff G, Lacas B, et al. Prognostic and Predictive Effect of TP53 Mutations in Patients with Non-Small Cell Lung Cancer from Adjuvant Cisplatin-Based Therapy Randomized Trials: A LACE-Bio Pooled Analysis. J Thorac Oncol 2016;11:850-61. [Crossref] [PubMed]
  34. Wei Y, Shen K, Lv T, et al. Three new disease-progression modes in NSCLC patients after EGFR-TKI treatment by next-generation sequencing analysis. Lung Cancer 2018;125:43-50. [Crossref] [PubMed]
  35. Brown H, Vansteenkiste J, Nakagawa K, et al. Programmed Cell Death Ligand 1 Expression in Untreated EGFR Mutated Advanced NSCLC and Response to Osimertinib Versus Comparator in FLAURA. J Thorac Oncol 2020;15:138-43. [Crossref] [PubMed]
  36. Su S, Dong ZY, Xie Z, et al. Strong Programmed Death Ligand 1 Expression Predicts Poor Response and De Novo Resistance to EGFR Tyrosine Kinase Inhibitors Among NSCLC Patients With EGFR Mutation. J Thorac Oncol 2018;13:1668-75. [Crossref] [PubMed]
  37. Hsu KH, Huang YH, Tseng JS, et al. High PD-L1 expression correlates with primary resistance to EGFR-TKIs in treatment naïve advanced EGFR-mutant lung adenocarcinoma patients. Lung Cancer 2019;127:37-43. [Crossref] [PubMed]
  38. Kang M, Park C, Kim SH, et al. Programmed death-ligand 1 expression level as a predictor of EGFR tyrosine kinase inhibitor efficacy in lung adenocarcinoma. Transl Lung Cancer Res 2021;10:699-711. [Crossref] [PubMed]
  39. Hsu KH, Tseng JS, Yang TY, et al. PD-L1 strong expressions affect the clinical outcomes of osimertinib in treatment naïve advanced EGFR-mutant non-small cell lung cancer patients. Sci Rep 2022;12:9753. [Crossref] [PubMed]
  40. Cha YJ, Kim HR, Lee CY, et al. Clinicopathological and prognostic significance of programmed cell death ligand-1 expression in lung adenocarcinoma and its relationship with p53 status. Lung Cancer 2016;97:73-80. [Crossref] [PubMed]
  41. Jin Y, Xue Q, Shen X, et al. PD-L1 Expression and Comprehensive Molecular Profiling Predict Survival in Nonsmall Cell Lung Cancer: A Real-World Study of a Large Chinese Cohort. Clin Lung Cancer 2022;23:43-51. [Crossref] [PubMed]
  42. Schmid S, Li JJN, Leighl NB. Mechanisms of osimertinib resistance and emerging treatment options. Lung Cancer 2020;147:123-9. [Crossref] [PubMed]
  43. Hartmaier RJ, Markovets AA, Ahn MJ, et al. Osimertinib + Savolitinib to Overcome Acquired MET-Mediated Resistance in Epidermal Growth Factor Receptor-Mutated, MET-Amplified Non-Small Cell Lung Cancer: TATTON. Cancer Discov 2023;13:98-113. [Crossref] [PubMed]
  44. Felip E, Cho BC, Gutiérrez V, et al. Amivantamab plus lazertinib versus osimertinib in first-line EGFR-mutant advanced non-small-cell lung cancer with biomarkers of high-risk disease: a secondary analysis from MARIPOSA. Ann Oncol 2024;35:805-16. [Crossref] [PubMed]
  45. Planchard D, Jänne PA, Cheng Y, et al. Osimertinib with or without Chemotherapy in EGFR-Mutated Advanced NSCLC. N Engl J Med 2023;389:1935-48. [Crossref] [PubMed]
Cite this article as: Kim SE, Kim Y, Yoon DK, Park H, Park KS, Kim D, Hwang HS, Ahn B, Park JE, Kim SW, Jang SJ, Yoon S, Lee HS, Lee DH. Exon-level TP53 alterations and PD-L1 expression identified by pretreatment NGS stratify survival in EGFR-mutant non-small cell lung cancer treated with first-line osimertinib. Transl Lung Cancer Res 2025;14(12):5283-5295. doi: 10.21037/tlcr-2025-880

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