Concomitant mutation status of ALK-rearranged non-small cell lung cancers and its prognostic impact on patients treated with crizotinib

Clinical significance of TP53 alterations in advanced NSCLC patients treated with EGFR, ALK and ROS1 tyrosine kinase inhibitors: An update

 The development of targeted therapies for non-small cell lung cancer (NSCLC), such as the epidermal growth factor receptor (EGFR), anaplastic lymphoma receptor tyrosine kinase (ALK), and ROS proto-oncogene 1 (ROS1), has improved patients' prognosis and significantly extended progression-free survival. However, it remains unclear why some patients do not benefit from the treatment as much or have a rapid disease progression. It is considered that, apart from the oncogenic driver gene, molecular alterations in a number of caretaker and gatekeeper genes significantly impact the efficacy of targeted therapies. The tumor protein 53 (TP53) gene is one of the most frequently mutated genes in NSCLC. To date, numerous studies have investigated the influence of various TP53 alterations on patient prognosis and responsiveness to therapies targeting EGFR, ALK, or ROS1. This review focuses on the latest data concerning the role of TP53 alterations as prognostic and/or predictive biomarkers for EGFR, ALK, and ROS1 tyrosine kinase inhibitors (TKIs) in advanced NSCLC patients. Since the presence of TP53 mutations in NSCLC has been linked to its decreased responsiveness to EGFR, ALK, and ROS1 targeted therapy in most of the referenced studies, the review also discusses the impact of TP53 mutations on treatment resistance. It seems plausible that assessing the TP53 mutation status could aid in patient stratification for optimal clinical decision-making. However, drawing meaningful conclusions about the clinical value of the TP53 co-mutations in EGFR-, ALK- or ROS1-positive NSCLC is hampered mainly by an insufficient knowledge regarding the functional consequences of the TP53 alterations. The integration of next-generation sequencing into the routine molecular diagnostics of cancer patients will facilitate the detection and identification of targetable genetic alterations along with co-occurring TP53 variants. This advancement holds the potential to accelerate understanding of the biological and clinical role of p53 in targeted therapies for NSCLC.

The impact of genomic context on outcomes of solid cancer patients treated with genotype-matched targeted therapies: a comprehensive review

INTRODUCTION

A critical need in the field of genotype-matched targeted therapy in cancer is to identify patients unlikely to respond to precision medicines. This will manage expectations of individualised therapies and avoid clinical progression to a point where institution of alternative treatments might not be possible. We examined the evidence base of the impact of genomic context on which targeted alterations are inscribed to identify baseline biomarkers distinguishing those obtaining the expected response from those with less benefit from targeted therapies.

METHODS

A comprehensive narrative review was conducted: scoping searches were undertaken in PubMed, Cochrane Database of Systematic Reviews, and PROSPERO. Outcomes included in meta-analysis were progression-free and overall survival. Data were extracted from Kaplan-Meier and used to calculate hazard ratios. Studies presenting data on two molecular subcohorts (e.g. co-mutation versus no co-mutation) were included in fixed meta-analysis. Other studies were used for descriptive purposes.

RESULTS

The presence of concomitant driver mutations, higher tumour mutational burden (TMB), greater copy number burden, and APOBEC signatures significantly reduces benefits of targeted therapy in lung cancers in never smokers (LCINS - less than 100 cigarettes per lifetime) and breast cancer, cancers with low TMB. LCINS have significantly poorer outcomes if their cancers harbour p53 co-mutations, an effect also seen in human epidermal growth factor receptor 2-positive (HER2+) breast cancer patients (trastuzumab) and head and neck cancer patients [phosphoinositide 3-kinase (PI3K) inhibition]. PI3K co-alterations have less impact when targeting epidermal growth factor receptor mutations and anaplastic lymphoma kinase fusions, but significantly reduce the impact of targeting HER2 and MET amplifications. SMARCA4 co-mutations predict for poor outcome in patients treated with osimertinib and sotorasib. In BRAF-mutant melanoma, whilst there are no genomic features distinguishing exceptional responders from primary progressors, there are clear transcriptomic features dichotomising these outcomes.

CONCLUSION

To our knowledge, this is the most comprehensive review to date of the impact of genomic context on outcomes with targeted therapy. It represents a valuable resource informing progress towards contextualised precision medicine.

Superior clinical outcomes in patients with non-small cell lung cancer harboring multiple ALK fusions treated with tyrosine kinase inhibitors

Background

Patients with non-small cell lung cancer (NSCLC) harboring anaplastic lymphoma kinase (ALK) fusions may benefit from ALK-tyrosine kinase inhibitors (ALK-TKIs). However, few studies have analyzed the clinical outcome in patients harboring multiple ALK fusions, including double or triple ALK fusions. Here, our study aimed to analyze the impact of harboring multiple ALK fusions on the efficacy of receiving ALK-TKIs in NSCLC patients.

Methods

A total of 125 patients with ALK-rearranged NSCLC detected by targeted capture DNA-based next-generation sequencing (NGS) at West China Hospital were enrolled. The literature on patients harboring multiple ALK fusions was systematically reviewed. The clinical response to ALK-TKIs was evaluated according to ALK fusion patterns in 62 patients: 56 from our center and 6 from the literature.

Results

Among the 125 patients, a single canonical echinoderm microtubule-associated protein-like 4 (EML4)-ALK fusion was detected in 65.6% (82/125), a single non-EML4-ALK fusion was detected in 13.6% (17/125), and multiple ALK fusions were detected in 20.8% (26/125). Among the 62 patients with ALK fusion treated with ALK-TKIs, the median progression-free survival (PFS) was significantly longer in patients with multiple ALK fusions than in those with a single ALK fusion (26.9 vs. 11.2 months, P=0.009), irrespective of brain metastasis, type of TKI drug, and treatment lines. The multiple ALK fusion group also tended to have a longer overall survival (OS) (P=0.26). Multivariate Cox regression analysis revealed that harboring multiple ALK fusions had the potential to be an independent predictor of better PFS for ALK-positive NSCLC [hazard ratio (HR) =0.490; 95% confidence interval (CI): 0.229-1.049].

Conclusions

Harboring multiple ALK fusions could serve as an independent predictive marker of better clinical outcome for patients with NSCLC and ALK rearrangement who have received ALK-TKIs treatment.

Partial Response to Crizotinib in a Lung Adenocarcinoma Patient with a Novel FBXO11 (Intergenic)-ALK (Exon 20-29) Fusion

Intergenic-gene fusion detected by DNA-seq is particularly confusing for drug selection since the function of the intergenic region located upstream is unknown. We reported a case of a 49-year-old male with advanced lung adenocarcinoma, who was detected FBXO11 (intergenic)-ALK (exon 20-29) by DNA-seq, and FISH analysis revealed a positive result. The patient was treated with crizotinib and achieved a PR. The canonical EML4 (exon 1-13)-ALK (exon 20-29) fusion verified by RNA-seq suggested a complex EML4 (exon 1-13)-FBXO11 (intergenic)-ALK (exon 20-29) tripartite rearrangement at the DNA level. Our case emphasized the necessity of RNA-seq for verifying intergenic-gene fusion. Simultaneously, the pathogenic germline SLX4 variant and extensive CNVs of DNA segment were detected by DNA-seq deserves our attention.

A clinical risk model for assessing the survival of patients with stage IA-IIA non-small cell lung cancer after surgery

BACKGROUND

The survival of patients with stage IA-IIA non-small cell lung cancer (NSCLC) after surgery is heterogeneous. This study aimed to construct a prognostic risk model to predict the overall survival (OS) of these patients.

METHODS

Data from patients (n=9,914) from the Surveillance Epidemiology and End Results (SEER) database were analyzed. The cases were randomly divided into the training and the validation groups. Patients from the Shanghai Pulmonary Hospital (n=270) were also included as an external cohort. Independent significant factors affecting survival in the training cohort were used to construct a nomogram. The precision was evaluated using the concordance index (C-index) and calibration plots. The X-tile software was used to confirm the optimal cut-off value to classify the patients.

RESULTS

Sex, age at diagnosis, tumor size, visceral pleura invasion (VPI), tumor grade, and the number of examined lymph nodes were deemed independent prognostic factors and were selected to establish the nomogram. The C-indices of the nomogram for predicting OS were 0.671 [95% confidence interval (CI): 0.653-0.689] in the training group, and 0.668 (95% CI: 0.650-0.687) and 0.707 (95% CI: 0.651-0.763) in the validation and the testing groups, respectively. The cut-off value of risk points was 106.0, which stratified the patients into high-risk and low-risk groups. The high-risk patients had shorter 5-year OS than low-risk patients (P<0.001).

CONCLUSIONS

The established nomogram could evaluate the survival in patients with stage IA-IIA NSCLC after surgery and may provide prognostic information for clinicians to make decisions in the management of adjuvant therapy.

Genetic correlation of crizotinib efficacy and resistance in ALK- rearranged non-small-cell lung cancer

OBJECTIVES

Crizotinib remains one of the most commonly used targeted therapies for ALK fusion-positive patients. However, the mutational profiles and mechanisms of resistance to first-line crizotinib treatment remain to be thoroughly examined.

MATERIALS AND METHODS

We retrospectively reviewed 125 ALK-positive patients with histological and/or cytological diagnosis of NSCLC. Of these, baseline samples were available from 62 patients and 63 had resistance samples following first-line crizotinib treatment, with 18 patients having paired baseline and resistance samples. All patients were genetically profiled by NGS using a 139 lung cancer gene panel (Pulmocan®, Nanjing Geneseeq Technology Inc.). Survival associations of progression-free survival (PFS) and resistance mechanisms were evaluated in relation to ALK fusion variants and background genetic alterations.

RESULTS

The median age of the cohort was 53 years old (range 26-78; 46.4 % females). Three novel ALK fusion partners were identified, including PSME4, cullin3 (CUL3) and coiled-coil domain containing 85A (CCDC85A). Among the different ALK fusion genes, patients carrying the v3 variant experienced worse PFS outcome compared with other non-v3 fusions (P = 0.01) in response to first-line crizotinib. Profiling of the genetic landscape revealed TP53 as the most frequently co-mutated gene, alterations of which were associated with unfavorable outcome (P = 0.024) and were among the secondary acquired mutations in the resistance samples. Examinations of the resistance mechanisms showed that the v3 variant was more likely to acquire ALK activating mutations (P = 0.04). Off-target resistance mechanisms included mutations in genes in the RAS/MAPK and its parallel pathway genes, such as ERBB2, BRAF, KRAS, FGFR3, NF1 and CREBBP.

CONCLUSION

In this study, through profiling of the mutational landscape of ALK-positive advanced NSCLCs both at baseline and disease progression, we characterized resistance mechanisms and molecular correlations of PFS in response to first-line crizotinib. Our findings may facilitate rational selection of subsequent ALK TKIs in the clinic.

Special issue "The advance of solid tumor research in China": Real-world clinical outcomes of alectinib for advanced non-small-cell lung cancer patients with ALK fusion in China

Global phase 3 trials have demonstrated the priority of several next-generation anaplastic lymphoma kinase-tyrosine kinase inhibitors (ALK-TKIs). However, clinical studies are conducted with specific populations that differ from the real world. The study aimed to evaluate the clinical outcomes of alectinib in real-world settings. Patients with advanced non-small-cell lung cancer (NSCLC) and EML4-ALK fusion were enrolled from two medical centers between June 2018 and June 2020. The primary endpoints were objective response rate (ORR) and progression-free survival (PFS) to alectinib. The secondary endpoint was response of brain metastases. The risk factors for disease progression were also investigated. In total, 127 patients with advanced NSCLC were enrolled into this study. Of them, 54.3% received first-line alectinib. The 1- and 2-year PFS rates were 77.4% and 68.3%, respectively. ORR and disease control rate (DCR) were 53.5% and 91.3%, respectively. Among patients with brain metastases, intracranial ORR and DCR were 63.6% and 88.6%, respectively. In addition, we found that "crizotinib pretreatment", "liver metastasis", and "TP53 co-mutation" were individually associated with shorter PFS in alectinib treatment. In conclusion, this study confirms the salient clinical outcomes of alectinib for ALK-fusion-driven NSCLC patients with or without brain metastases, adding real-world evidence to the priority of alectinib in clinical practice. This article is protected by copyright. All rights reserved.

Molecular charcterization of lung adenocarcinoma combining whole exome sequencing, copy number analysis and gene expression profiling

INTRODUCTION

Lung cancer is the leading cause of cancer mortality worldwide; lung adenocarcinoma (LUAD) corresponds to about 40% of lung cancers. LUAD is a genetically heterogeneous disease and the definition of this heterogeneity is of fundamental importance for prognosis and treatment.

AREAS COVERED

Based on primary literature, this review provides an updated analysis of multiomics studies based on the study of mutation profiling, copy number alterations and gene expression allowing for definition of molecular subgroups, prognostic factors based on molecular biomarkers, and identification of therapeutic targets. The authors sum up by providing the reader with their expert opinion on the potentialities of multiomics analysis of LUADs.

EXPERT OPINION

A detailed and comprehensive study of the co-occurring genetic abnormalities characterizing different LUAD subsets represents a fundamental tool for a better understanding of the disease heterogeneity and for the identification of subgroups of patients responding or resistant to targeted treatments and for the discovery of new therapeutic targets. It is expected that a comprehensive characterization of LUADs may provide a fundamental contribution to improve the survival of LUAD patients.

The impact of the ALK fusion variant on clinical outcomes in EML4-ALK patients with NSCLC: a systematic review and meta-analysis

Background: Recent studies showed that ALK-fusion variants are associated with heterogeneous clinical outcomes. However, contradictory conclusions have been drawn in other studies showing no correlation between ALK variants and prognoses. Methods: A systematic review and meta-analysis was performed to evaluate the prognostic value of EML4-ALK fusion variants for patient outcomes. Results: 28 studies were included in the analysis. According to the pooled results, patients harboring variant 1 showed equivalent progression-free survival (PFS) and overall survival (OS) with non-v1 patients (hazard ratio [HR] for PFS: 0.91 [0.68-1.21]; p = 0.499; OS: 1.12 [0.73-1.72]; p = 0.610). Similarly, patients with v3 showed the same disease progress as non-v3 patients (pooled HR for PFS = 1.07 [0.72-1.58]; p = 0.741). However, pooled results for OS suggested that patients with v3 had worse survival than non-v3 patients (HR = 3.44 [1.42-8.35]; p = 0.006). Conclusion: Results suggest that patients with v1 exhibited no significant difference from non-v1 in terms of OS and PFS, while v3 was associated with shorter OS in ALK-positive patients with non-small cell lung cancer.

Case Report: Identification of Two Rare Fusions, PDK1-ALK and STRN-ALK, That Coexist in a Lung Adenocarcinoma Patient and the Response to Alectinib

Several double ALK fusions coexisting in one patient have been reported. However, few studies have reported the clinical efficacy of ALK inhibitors in rare double ALK fusions. Here, we described a rare PDK1-ALK, STRN-ALK double-fusion variant in a patient with metastatic lung adenocarcinoma. The patient responded well to alectinib (600 mg) twice daily. This case shows a promising treatment option for patients with rare ALK double-fusion variants.