TP53 Co-Mutations in Advanced EGFR-Mutated Non-Small Cell Lung Cancer: Prognosis and Therapeutic Strategy for Cancer Therapy

Comprehensive genomic profiling reveals a unique genomic landscape in solid tumors in an Indian cancer cohort of 1000 patients: a single institutional experience

The use of Comprehensive Genomic Profiling (CGP) in clinical practice to detect broad-spectrum therapeutic, prognostic, and predictive biomarkers, including tumor mutational burden (TMB), microsatellite instability (MSI), somatic BRCA (sBRCA) and other homologous recombination repair genes (HRRs) provides a more cost-efficient and tissue-preserving approach than serial single-biomarker analysis. A total of 1000 biopsy-proven cancer patients at the HCG cancer center were profiled in an IRB-approved prospective study. The findings were discussed in the multidisciplinary molecular tumor board (MTB), and recommendations were documented in electronic medical records (EMRs) for clinical management and follow-up. A total of 1747 genomic alterations were detected (mean 1.7 mutations/sample), with 80% of patients having genetic alterations with therapeutic and prognostic implications (Tier I-32%, Tier II-50%). CGP revealed a greater number of druggable genes (47%) than did small panels (14%). Tumor-agnostic markers for immunotherapy (IO) were observed in 16% of the current cohort, based on which IO was initiated. In 13.5% of the cohort, alterations in the HRR pathway including sBRCA (5.5%) were detected providing an option for treatment with platinum or PARP inhibitors. Other significant alterations included those in EGFR, KRAS/BRAF, PIK3CA, cKIT, PDGFRA, ARID1A, ARID2, and FGFR. RNA sequencing revealed 55 + RNA alterations, including those in TMPRSS-ERG, RPS6KB1-VMP1, EML4-ALK, NTRK, PDGFRA and EWSR. Clinical outcome data were available via EMR for 618 patients (62%), out of whom 419 patients had druggable mutations (67%; 95% CI 88.9-93.9%) and 39 patients had 1 or more mutations with prognostic implications. However, only 200 patients (44%; 95% CI 39.1-48.1%) were included in the MTB discussion. Based on genomics reports, the treatment regimen was changed for 137 and 61 patients with and without clinical inputs from the MTB, respectively. The overall change in therapy based on CGP in the clinical cohort was 43%, which was greater in patients enrolled for MTB than in patients who had not undergone MTB. At the interim analysis, with a median follow-up of 18 months (range 12-24 months) after the change in therapy as per genomics report, 97 patients (71%) were found to be alive thus establishing the importance of CGP and MTB in personalized genomics-driven treatment.

Role of TP53 Mutations and EGFR Amplification in Risk Stratification of Early-Stage EGFR-Mutated Non-Small Cell Lung Cancer With Immunohistochemistry as a Surrogate Marker

BACKGROUND

Non-small cell lung carcinoma (NSCLC) is a leading cause of cancer-related mortality, with recurrence risks posing significant challenges in early-stage disease management. While epidermal growth factor receptor (EGFR) mutations are common, the role of concurrent genetic alterations remains underexplored, and findings have often been inconsistent, particularly in early-stage tumors.

METHODS

We retrospectively analyzed 424 EGFR-mutated NSCLC patients diagnosed from 2017 to 2022. Next-generation sequencing (NGS) was used to identify genetic alterations, and immunohistochemistry (IHC) was employed to correlate TP53 mutations and EGFR amplification with protein expression. Survival outcomes were assessed using Kaplan-Meier and Cox regression analyses, while predictive cutoffs were determined with receiver operating characteristic (ROC) curve analysis.

RESULTS

TP53 mutations and EGFR amplification were more prevalent in Stages 2-4 compared to Stage 1 (p < 0.001 and 0.005, respectively). In Stage 1, TP53 mutations, particularly exon 4 and frameshift/nonsense types, were associated with worse overall survival (OS) and disease-free survival (DFS). EGFR amplification was linked to shorter DFS in Stage 1 (p = 0.006). Both alterations correlated with aggressive pathological features, including advanced N stage, lymphovascular invasion, and high histological grade. IHC cutoffs of 15% for TP53 and H-score ≥ 180 for EGFR amplification demonstrated high predictive accuracy (AUC = 0.981 and 0.936, respectively).

CONCLUSION

Specific subtypes of TP53 mutations and EGFR amplification are important prognostic markers in early-stage NSCLC. IHC offers a practical surrogate for genetic testing, aiding in risk stratification and guiding adjuvant therapy decisions for high-risk patients. Larger validation studies are warranted.

Molecular residual disease analysis of adjuvant osimertinib in resected EGFR-mutated stage IB-IIIA non-small-cell lung cancer

Osimertinib-a third-generation epidermal growth factor receptor-tyrosine kinase inhibitor-is recommended as adjuvant therapy for resected stage IB-IIIA epidermal growth factor receptor-mutated non-small-cell lung cancer, based on significant disease-free survival (DFS) and overall survival improvement shown in the previously reported phase 3 ADAURA trial. A trend toward an increased DFS event rate after completion of 3 years adjuvant treatment in ADAURA suggests that some patients may benefit from longer adjuvant osimertinib treatment. We therefore explored whether tumor-informed, circulating tumor DNA-based, molecular residual disease (MRD) could predict recurrence in an exploratory post hoc analysis of 220 patients (n = 112 osimertinib; n = 108 placebo) from ADAURA. MRD preceded imaging DFS events in this study by a median of 4.7 (95% confidence interval, 2.2-5.6) months. DFS and MRD event-free rate at 36 months was 86% versus 36% for patients in the osimertinib versus placebo groups (hazard ratio, 0.23 (95% confidence interval, 0.15-0.36)). In the osimertinib group, DFS or MRD events were detected in 28 (25%) patients; most events occurred following osimertinib cessation (19 of 28, 68%) and within 12 months of stopping osimertinib (11 of 19, 58%). At 24 months after osimertinib, the DFS and MRD event-free rate was 66%. In this study, MRD preceded DFS events in most patients across both arms. DFS and MRD event-free status was maintained for most patients during adjuvant osimertinib treatment and posttreatment follow-up, with most MRD or DFS events occurring after osimertinib treatment discontinuation or completion. MRD detection could potentially identify patients who may benefit from longer adjuvant osimertinib, although this requires clinical confirmation. ClinicalTrials.gov identifier: NCT02511106 .

Effects of Tp53 Gene Mutations on the Survival of Non-Small Cell Lung Cancer (NSCLC); A Short Review

Non-small cell lung cancer (NSCLC) is the leading cause of cancer-related deaths worldwide. Mutations within the TP53 gene represent critical molecular events in NSCLC, contributing to the tumorigenesis in the pulmonary epithelial tissues. TP53 is a widely researched prognostic indicator in NSCLC, and pathological investigations have revealed a weak to mild negative predictive effect for TP53. Mutated p53 protein may have some pro-oncogenic impact, and the variations may change tumor inhibitors into oncogenes. The diverse mutational spectrum of TP53 in NSCLC with different mutations is linked to varied treatment responses. In contrast, first-line chemotherapeutics to this progress are limited, however, randomized trials with new chemotherapeutics have shown significant survival benefits. This review highlighted the critical influence of TP53 gene mutations on pathological-sensitivity and overall survival outcomes in NSCLC. Further research is needed to explore TP53 mutation-specific pathways and their effects on NSCLC progression and treatment effectiveness.

RNAi screens identify HES4 as a regulator of redox balance supporting pyrimidine synthesis and tumor growth

NADH/NAD+ redox balance is pivotal for cellular metabolism. Systematic identification of NAD(H) redox regulators, although currently lacking, would help uncover unknown effectors critically implicated in the coordination of growth metabolism. In this study, we performed a genome-scale RNA interference (RNAi) screen to globally survey the genes involved in redox modulation and identified the HES family bHLH transcription factor HES4 as a negative regulator of NADH/NAD+ ratio. Functionally, HES4 is shown to be crucial for maintaining mitochondrial electron transport chain (ETC) activity and pyrimidine synthesis. More specifically, HES4 directly represses transcription of SLC44A2 and SDS, thereby inhibiting mitochondrial choline oxidation and cytosolic serine deamination, respectively, which, in turn, ensures coenzyme Q reduction capacity for DHODH-mediated UMP synthesis and serine-derived dTMP production. Accordingly, inhibition of choline oxidation preserves mitochondrial serine catabolism and ETC-coupled redox balance. Furthermore, HES4 protein stability is enhanced under EGFR activation, and increased HES4 levels facilitate EGFR-driven tumor growth and predict poor prognosis of lung adenocarcinoma. These findings illustrate an unidentified mechanism, underlying pyrimidine biosynthesis in the intersection between serine and choline catabolism, and underscore the physiological importance of HES4 in tumor metabolism.

'Plasma first' approach for detecting epidermal growth factor receptor mutation in advanced non-small cell lung carcinoma

INTRODUCTION

The treatment approach for recently diagnosed advanced non-small cell lung cancer (NSCLC) with EGFR mutations primarily relies on confirming the tissue diagnosis as non-squamous NSCLC. This routine clinical practice of tissue diagnosis imposes several barriers and delays in turnaround time (TAT) for biomarker testing, significantly delaying the time to treatment. The objective of this study is to investigate the 'plasma first' approach for detection of EGFR mutation in advanced stage treatment naïve NSCLC patients.

METHODS

We prospectively collected blood samples of treatment naïve patients with clinical and radiological suspicion of advanced stage NSCLC prior to obtaining tissue biopsy. Plasma cfDNA was tested for EGFR mutation using two different methods. We compared the sensitivity and TAT of liquid biopsy with tissue biopsy.

RESULTS

In total, we analyzed plasma cell-free DNA (cfDNA) of 236 patients suspected of having advanced NSCLC for EGFR mutations. We observed a notably shorter turnaround time (TAT) of 3 days, which was significantly quicker compared to the 12-day TAT for tissue biopsy (p < 0.05). The ddPCR method had a sensitivity of 82.8%, which was higher than 66.34% sensitivity of ARMS-PCR. The current study also highlights that there is no significant difference in the clinical outcome of the patients whether treated based on liquid biopsy only or tissue biopsy (median progression-free survival of 11.56 vs. 11.9 months; p = 0.94).

CONCLUSIONS

Utilizing a 'plasma first' strategy, given its shorter turnaround time, strong positive concordance and comparable outcomes to tissue biopsy, emerges as a highly specific and reliable method for detecting EGFR mutations in advanced-stage NSCLC.

Influence of TP53 mutation on efficacy and survival in advanced EGFR-mutant non-small cell lung cancer patients treated with third-generation EGFR tyrosine kinase inhibitors

TP53 comutation is related to poor prognosis of non-small cell lung cancer. However, there is limited study focusing on the structural influence of TP53 mutation on third-generation epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs) treatment. We retrospectively analyzed the clinical and molecular data of patients treated with third-generation EGFR-TKIs in two independent cohorts. A total of 117 patients from the Sun Yat-sen University Cancer Center (SYSUCC) and 141 patients from the American Association for Cancer Research Project GENIE database were included. In the SYSUCC cohort, TP53 comutations were found in 59 patients (50.4%) and were associated with poor median progress-free survival (mPFS) and median overall survival (mOS). The additional subtype analysis found that TP53 mutation in the alpha-helix region had shorter mOS compared with those with TP53 mutations in other regions in the SYSUCC cohort (mOS, 12.2 vs. 21.7 months; p = 0.027). Similar findings were confirmed in the GENIE cohort. Specifically, the presence of TP53 mutation in the alpha-helix region was an independent negative predictive factor for PFS [hazard ratio (HR) 2.05(1.01-4.18), p = 0.048] and OS [HR 3.62(1.60-8.17), p = 0.002] in the SYSUCC cohort. TP53 mutation in alpha-helix region was related to inferior clinical outcomes in patients treated with third-generation EGFR-TKIs.

Study on the Mechanism of Yadanzi Oil in Treating Lung Cancer Based on Network Pharmacology and Molecular Docking Technology

Brucea javanica oil emulsion (BJOE) is a compound Chinese medicine used for treating various cancers, such as lung cancer. However, the exact mechanism of its antilung cancer active ingredient remains unclear. This study aims to explore and validate the effective active ingredients and mechanism of action of BJOE in the treatment of lung cancer through network pharmacology, molecular docking technology, and cell experiments. The results showed that there were 13 active ingredients, 136 target genes, and 42 disease target-coexpressed genes in BJOE. The molecular docking results indicated that the main active components of the oil emulsion, YD1 (β-sitosterol), YD2 (luteolin), and YD3 (bruceitol), could stably bind to TP53 and MAPK1. Furthermore, the commercially available β-sitosterol luteolin was used as a representative compound to conduct cell experiments to verify its anticancer activity and mechanism. It was found that luteolin can inhibit the proliferation better than β-sitosterol and the activity of lung cancer cells by regulating the expression of related proteins through the P53/MAPK1 signaling pathway. This study combines network pharmacology prediction with experiments to demonstrate the "multicomponent, multitarget, multipathway" approach of B. javanica oil emulsion in treating lung cancer.

Genomic heterogeneity at baseline is associated with T790M resistance mutations in EGFR-mutated lung cancer treated with the first-/second-generation tyrosine kinase inhibitors

This study analyzed whether extended molecular profiling can predict the development of epidermal growth factor receptor (EGFR) gene T790M mutation, which is the most frequent resistance alteration in non-small cell lung cancer (NSCLC) after treatment with the first-/second-generation (1G/2G) EGFR inhibitors (tyrosine kinase inhibitors [TKIs]), but only weakly associated with clinical characteristics. Whole exome sequencing (WES) was performed on pretreatment tumor tissue with matched normal samples from NSCLC patients with (n = 25, detected in tissue or blood rebiopsies) or without (n = 14, negative tissue rebiopsies only) subsequent EGFR p.T790M mutation after treatment with 1G/2G EGFR TKI. Several complex genetic biomarkers were assessed using bioinformatic methods. After treatment with first-line afatinib (44%) or erlotinib/gefitinib (56%), median progression-free survival and overall survival were 12.1 and 33.7 months, respectively. Clinical and tumor genetic characteristics, including age (median, 66 years), sex (74% female), smoking (69% never/light smokers), EGFR mutation type (72% exon 19 deletions), and TP53 mutations (41%) were not significantly associated with T790M mutation (p > 0.05). By contrast, complex biomarkers including tumor mutational burden, the clock-like mutation signature SBS1 + 5, tumor ploidy, and markers of subclonality including mutant-allele tumor heterogeneity, subclonal copy number changes, and median tumor-adjusted variant allele frequency were significantly higher at baseline in tumors with subsequent T790M mutation (all p < 0.05). Each marker alone could predict subsequent development of T790M with an area under the curve (AUC) of 0.72-0.77, but the small number of cases did not allow confirmation of better performance for biomarker combinations in leave-one-out cross-validated logistic regression (AUC 0.69, 95% confidence interval: 0.50-0.87). Extended molecular profiling with WES at initial diagnosis reveals several complex biomarkers associated with subsequent development of T790M resistance mutation in NSCLC patients receiving first-/second-generation TKIs as the first-line therapy. Larger prospective studies will be necessary to define a forecasting model.

Cell-Free DNA 5-Hydroxymethylcytosine Signatures for Lung Cancer Prognosis

Accurate prognostic markers are essential for guiding effective lung cancer treatment strategies. The level of 5-hydroxymethylcytosine (5hmC) in tissue is independently associated with overall survival (OS) in lung cancer patients. We explored the prognostic value of cell-free DNA (cfDNA) 5hmC through genome-wide analysis of 5hmC in plasma samples from 97 lung cancer patients. In both training and validation sets, we discovered a cfDNA 5hmC signature significantly associated with OS in lung cancer patients. We built a 5hmC prognostic model and calculated the weighted predictive scores (wp-score) for each sample. Low wp-scores were significantly associated with longer OS compared to high wp-scores in the training [median 22.9 versus 8.2 months; p = 1.30 × 10-10; hazard ratio (HR) 0.04; 95% confidence interval (CI), 0.00-0.16] and validation (median 18.8 versus 5.2 months; p = 0.00059; HR 0.22; 95% CI: 0.09-0.57) sets. The 5hmC signature independently predicted prognosis and outperformed age, sex, smoking, and TNM stage for predicting lung cancer outcomes. Our findings reveal critical genes and signaling pathways with aberrant 5hmC levels, enhancing our understanding of lung cancer pathophysiology. The study underscores the potential of cfDNA 5hmC as a superior prognostic tool for guiding more personalized therapeutic strategies for lung cancer patients.

Prognostic Factors and Markers in Non-Small Cell Lung Cancer: Recent Progress and Future Challenges

Lung cancer is a highly aggressive neoplasm and, despite the development of recent therapies, tumor progression and recurrence following the initial response remains unsolved. Several questions remain unanswered about non-small cell lung cancer (NSCLC): (1) Which patients will actually benefit from therapy? (2) What are the predictive factors of response to MAbs and TKIs? (3) What are the best combination strategies with conventional treatments or new antineoplastic drugs? To answer these questions, an integrative literature review was carried out, searching articles in PUBMED, NCBI-PMC, Google Academic, and others. Here, we will examine the molecular genetics of lung cancer, emphasizing NSCLC, and delineate the primary categories of inhibitors based on their molecular targets, alongside the main treatment alternatives depending on the type of acquired resistance. We highlighted new therapies based on epigenetic information and a single-cell approach as a potential source of new biomarkers. The current and future of NSCLC management hinges upon genotyping correct prognostic markers, as well as on the evolution of precision medicine, which guarantees a tailored drug combination with precise targeting.

New insights into the biology and development of lung cancer in never smokers-implications for early detection and treatment

Lung cancer is the leading cause of cancer deaths worldwide. Despite never smokers comprising between 10 and 25% of all cases, lung cancer in never smokers (LCNS) is relatively under characterized from an etiological and biological perspective. The application of multi-omics techniques on large patient cohorts has significantly advanced the current understanding of LCNS tumor biology. By synthesizing the findings of multi-omics studies on LCNS from a clinical perspective, we can directly translate knowledge regarding tumor biology into implications for patient care. Primarily focused on never smokers with lung adenocarcinoma, this review details the predominance of driver mutations, particularly in East Asian patients, as well as the frequency and importance of germline variants in LCNS. The mutational patterns present in LCNS tumors are thoroughly explored, highlighting the high abundance of the APOBEC signature. Moreover, this review recognizes the spectrum of immune profiles present in LCNS tumors and posits how it can be translated to treatment selection. The recurring and novel insights from multi-omics studies on LCNS tumor biology have a wide range of clinical implications. Risk factors such as exposure to outdoor air pollution, second hand smoke, and potentially diet have a genomic imprint in LCNS at varying degrees, and although they do not encompass all LCNS cases, they can be leveraged to stratify risk. Germline variants similarly contribute to a notable proportion of LCNS, which warrants detailed documentation of family history of lung cancer among never smokers and demonstrates value in developing testing for pathogenic variants in never smokers for early detection in the future. Molecular driver subtypes and specific co-mutations and mutational signatures have prognostic value in LCNS and can guide treatment selection. LCNS tumors with no known driver alterations tend to be stem-like and genes contributing to this state may serve as potential therapeutic targets. Overall, the comprehensive findings of multi-omics studies exert a wide influence on clinical management and future research directions in the realm of LCNS.

Management of Oncogene Driven Locally Advanced Unresectable Non-small Cell Lung Cancer

INTRODUCTION

The current standard of care of locally advanced non-small cell lung cancer (LA-NSCLC) is concurrent chemoradiation, followed by consolidation durvalumab. However, there is evidence that the efficacy of chemoradiation and also immunotherapy in many oncogene-positive LA-NSCLC are attenuated, and dependent on the subgroup.

AREAS COVERED

We will firstly review the outcomes of standard-of-care therapy in oncogene-driven LA-NSCLC. We looked at various oncogene driven subgroups and the tumor microenvironment that may explain differential response. Finally, we review the role of targeted therapy in the treatment of LA-NSCLC.

EXPERT OPINION

Each oncogene-positive subgroup should be treated as its own entity, and continued efforts should be undertaken to incorporate targeted therapy, which is likely to yield superior survival outcomes if trial design can be optimized and toxicities can be managed.

The role of oncogenes and tumor suppressor genes in determining survival rates of lung cancer patients in the population of North Sumatra, Indonesia

Background: Gaining a better understanding of molecular alterations in the pathogenesis of lung cancer reveals a significant change in approach to the management and prognosis of lung cancer. Several oncogenes and tumor suppressor genes have been identified and have different roles related to survival rates in lung cancer patients. This study aims to determine the role of KRAS, EGFR, and TP53 mutations in the survival rate of lung cancer patients in the population of North Sumatra. Methods: This is a retrospective cohort study involving 108 subjects diagnosed with lung cancer from histopathology specimens. DNA extractions were performed using FFPE followed by PCR examinations for assessing the expressions of EGFR, RAS, and TP53 protein. Sequencing analysis was carried out to determine the mutations of EGFR exon 19 and 21, RAS protein exon 2, and TP53 exon 5-6 and 8-9. Data input and analysis were conducted using statistical analysis software for Windows. The survival rate analysis was presented with Kaplan Meier. Results: 52 subjects completed all procedures in this study. Most of the subjects are male (75%), above 60 years old (53.8%), heavy smokers (75%), and suffer from adenocarcinoma type of lung cancer (69.2%). No subjects showed KRAS exon 2 mutations. Overall survival rates increased in patients with EGFR mutations (15 months compared to 8 months; p=0.001) and decreased in patients with TP53 mutations (7 months compared to 9 months; p=0.148). Also, there was increasing Progression-Free Survival in patients with EGFR mutations (6 months compared to 3 months) ( p=0.19) and decreasing PFS in patients with TP53 mutations (3 months compared to 6 months) ( p=0.07). Conclusions: There were no KRAS mutations in this study. EGFR mutations showed a higher survival rate, while TP53 mutations showed a lower survival rate in overall survival and progression-free survival.

Tp53 haploinsufficiency is involved in hotspot mutations and cytoskeletal remodeling in gefitinib-induced drug-resistant EGFRL858R-lung cancer mice

Tumor heterogeneity is the major factor for inducing drug resistance. p53 is the major defender to maintain genomic stability, which is a high proportion mutated in most of the cancer types. In this study, we established in vivo animal models of gefitinib-induced drug-resistant lung cancer containing EGFR^L858R and EGFR^L858R*Tp53^+/- mice to explore the molecular mechanisms of drug resistance by studying the genomic integrity and global gene expression. The cellular morphology of the lung tumors between gefitinib-induced drug-resistant mice and drug-sensitive mice were very different. In addition, in drug-resistant mice, the expression of many cytoskeleton-related genes were changed, accompanied by decreased amounts of actin filaments and increased amounts of microtubule, indicating that significant cytoskeletal remodeling is induced in gefitinib-induced drug-resistant EGFR^L858R and EGFR^L858R*Tp53^+/- lung cancer mice. The gene expression profiles and involved pathways were different in gefitinib-sensitive, gefitinib-resistant and Tp53^+/--mice. Increases in drug resistance and nuclear size (N/C ratio) were found in EGFR^L858R*Tp53^+/- drug-resistant mice. Mutational hotspot regions for drug resistance via Tp53^+/+- and Tp53^+/--mediated pathways are located on chromosome 1 and chromosome 11, respectively, and are related to prognosis of lung cancer cohorts. This study not only builds up a gefitinib-induced drug-resistant EGFR^L858R lung cancer animal model, but also provides a novel mutation profile in a Tp53^+/+- or Tp53^+/--mediated manner and induced cytoskeleton remodeling during drug resistance, which could contribute to the prevention of drug resistance during cancer therapy.

Concomitant TP53 mutation in early-stage resected EGFR-mutated non-small cell lung cancer: a narrative approach in a genetically admixed Brazilian cohort

TP53 mutations are frequent in non-small cell lung cancer (NSCLC) and have been associated with poor outcome. The prognostic and predictive relevance of EGFR/TP53 co-mutations in NSCLC is controversial. We analyzed lung tissue specimens from 70 patients with NSCLC using next-generation sequencing to determine EGFR and TP53 status and the association between these status with baseline patient and tumor characteristics, adjuvant treatments, relapse, and progression-free (PFS) and overall survival (OS) after surgical resection. We found the EGFR mutation in 32.9% of patients (20% classical mutations and 12.9% uncommon mutations). TP53 missense mutations occurred in 25.7% and TP53/EGFR co-mutations occurred in 43.5% of patients. Stage after surgical resection was significantly associated with OS (P=0.028). We identified an association between progression-free survival and poor outcome in patients with distant metastases (P=0.007). We found a marginally significant difference in OS between genders (P=0.057) and between mutant and wild type TP53 (P=0.079). In univariate analysis, distant metastases (P=0.027), pathological stage (IIIA-IIIB vs I-II; P=0.028), and TP53 status (borderline significance between wild type and mutant; P=0.079) influenced OS. In multivariable analysis, a significant model for high risk of death and poor OS (P=0.029) selected patients in stage IIIA-IIIB, with relapse and distant metastases, non-responsive to platin-based chemotherapy and erlotinib, with tumors harboring EGFR uncommon mutations, with TP53 mutant, and with EGFR/TP53 co-mutations. Our study suggested that TP53 mutation tends to confer poor survival and a potentially negative predictive effect associated with a non-response to platinum-based chemotherapy and erlotinib in early-stage resected EGFR-mutated NSCLC.

Utility of Next-Generation Sequencing in the Reconstruction of Clonal Architecture in a Patient with an EGFR Mutated Advanced Non-Small Cell Lung Cancer: A Case Report

EGFR tyrosine kinase inhibitors (EGFR-TKIs) have revolutionized the treatment of non-small cell lung cancer (NSCLC) patients with activating EGFR mutations. However, targeted therapies impose a strong selective pressure against the coexisting tumor populations that lead to the emergence of resistant clones. Molecular characterization of the disease is essential for the clinical management of the patient, both at diagnosis and after progression. Next-generation sequencing (NGS) has been established as a technique capable of providing clinically useful molecular profiling of the disease in tissue samples and in non-invasive liquid biopsy samples (LB). Here, we describe a case report of a patient with metastatic NSCLC harboring EGFR mutation who developed two independent resistance mechanisms (EGFR-T790M and TP53 + RB1 mutations) to dacomitinib. Osimertinib given as a second-line treatment eliminated the EGFR-T790M population and simultaneously consolidated the proliferation of the TP53 + RB1 clone that eventually led to the histologic transformation to small-cell lung cancer (SCLC). Comprehensive NGS profiling revealed the presence of the TP53 + RB1 clone in the pretreatment biopsy, while EGFR-T790M was only detected after progression on dacomitinib. Implementation of NGS studies in routine molecular diagnosis of tissue and LB samples provides a more comprehensive view of the clonal architecture of the disease in order to guide therapeutic decision-making.