The Impact of Programmed Death-Ligand 1 Expression on the Prognosis of Early Stage Resected Non-Small Cell Lung Cancer: A Meta-Analysis of Literatures

Pulmonary Low Malignant Potential Adenocarcinoma: A Validation of the Proposed Criteria for This Novel Subtype

Adenocarcinoma (ADC) is the most common histologic type of lung cancer, including in situ (lepidic), minimally invasive, and invasive forms. While the former 2 types are associated with a favorable outcome, the latter includes tumors with variable behavior, often tumor stage-related. A recent study proposed strict morphologic criteria defining a new subgroup of resected stage I invasive ADC (16% of cases) with favorable outcomes (100% disease-specific survival), named "ADC of low malignant potential (LMP-ADC)." The following criteria were met: ≤3 cm size, nonmucinous histotype, ≥15% lepidic growth, and the absence of the following: high-grade patterns, >1 mitosis/2 mm 2 , necrosis, and vascular/pleural invasion. The aim of the present study was to validate the performance of such criteria to identify LMP-ADC in a series of 274 stage IA resected lung ADCs from a single institution. Thirty-four tumors (12.4%) met the proposed criteria for LMP-ADC, as confirmed by additional stains for mitotic figures, Ki67 index, and elastic fibers (helpful to assess alveolar wall invasion). Minor differences between the lepidic and invasive components were observed regarding cell atypia and proliferation. p53 was normally expressed by invasive tumor cells. Mutations occurred in known lung cancer genes (mostly KRAS and EGFR). Five patients (14.7%) developed disease progression and 2 of them (5.9%) died of the disease. In our series, the disease-specific survival was 94.1%. In conclusion, in resected invasive lung ADC, a subgroup presenting low-grade morphologic features and associated with favorable prognosis does exist. Morphologic criteria for LMP-ADC supported by ancillary techniques represent a valid tool to better define this novel subgroup and to refine the stratification of invasive lung ADC, possibly suggesting modified follow-up protocols, based on the observed indolent behavior in most cases.

Characteristics and prognostic analysis of patients with detected KRAS mutations in resected lung adenocarcinomas by peptide nucleic acid-locked nucleic acid polymerase chain reaction (PNA-LNA PCR) clamp method

Background

Kirsten rat sarcoma virus (KRAS) gene mutations are a type of driver mutation discovered in the 1980s, but for a long time no molecular targeted drugs were available for them. Recently, sotorasib was developed as a molecular targeted drug for KRAS mutations. It is therefore necessary to identify the characteristics of patients with KRAS mutations.

Methods

This was the single-institution retrospective study. Surgically resected tumors from lung adenocarcinoma patients were collected at a single institution from June 2016 to September 2019. Peptide nucleic acid-locked nucleic acid polymerase chain reaction (PNA-LNA PCR) clamp analysis of KRAS G12X mutations was compared with analysis by therascreen KRAS RGQ kit. The association between KRAS mutation status and patient characteristics and prognosis was assessed.

Results

Among 499 lung adenocarcinomas, KRAS mutations were evaluated in 197 cases, excluding stage IV lung cancer and tumors with epidermal growth factor receptor (EGFR) and anaplastic lymphoma kinase (ALK) mutations. KRAS G12X mutations were detected in 59 cases (29.9%). The highest frequency by gene mutation subtype was G12V in 23 cases (39.0%), followed by G12C in 16 cases (27.1%), G12D in 12 cases (20.3%), G12S in 4 cases (6.8%) and G12A in 2 cases. For the G12C mutation, the PNA-LNA PCR clamp and therascreen methods were consistent, but for the G12D and G12S mutations, the PNA-LNA PCR clamp method showed higher detection rates. In operable tumors, G12C mutations were more frequent in males, smokers, and patients with high expression of programmed death-ligand 1 (PD-L1), and had no correlation with prognosis.

Conclusions

By the PNA-LNA PCR clamp method, G12C mutation of surgical specimens was detected successfully. The PNA-LNA PCR clamp method is expected to be applied to the detection of druggable G12C mutations.

A Review of Biomarkers and Their Clinical Impact in Resected Early-Stage Non-Small-Cell Lung Cancer

The postoperative survival of early-stage non-small-cell lung cancer (NSCLC) patients remains unsatisfactory. In this review, we examined the relevant literature to ascertain the prognostic effect of related indicators on early-stage NSCLC. The prognostic effects of the epidermal growth factor receptor (EGFR), anaplastic lymphoma kinase (ALK), mesenchymal-epithelial transition (MET), C-ros oncogene 1 (ROS1), or tumour protein p53 (TP53) alterations in resected NSCLC remains debatable. Kirsten rat sarcoma viral oncogene homologue (KRAS) alterations indicate unfavourable outcomes in early-stage NSCLC. Meanwhile, adjuvant or neoadjuvant EGFR-targeted agents can substantially improve prognosis in early-stage NSCLC with EGFR alterations. Based on the summary of current studies, resected NSCLC patients with overexpression of programmed death-ligand 1 (PD-L1) had worsening survival. Conversely, PD-L1 or PD-1 inhibitors can substantially improve patient survival. Considering blood biomarkers, perioperative peripheral venous circulating tumour cells (CTCs) and pulmonary venous CTCs predicted unfavourable prognoses and led to distant metastases. Similarly, patients with detectable perioperative circulating tumour DNA (ctDNA) also had reduced survival. Moreover, patients with perioperatively elevated carcinoembryonic antigen (CEA) in the circulation predicted significantly worse survival outcomes. In the future, we will incorporate mutated genes, immune checkpoints, and blood-based biomarkers by applying artificial intelligence (AI) to construct prognostic models that predict patient survival accurately and guide individualised treatment.

Analysis of Molecular Biomarkers in Resected Early-Stage Non-Small Cells Lung Cancer: A Narrative Review

Simple Summary

In the last few years, the treatment of advanced NSCLC has radically changed after the development of new drugs against specific molecular targets. Moreover, multiple tumour biopsies have become mandatory in order to better select the appropriate targeted therapy. Molecular analysis using NGS in the early stage of NSCLC is still relatively widespread. The recent clinical trials that use targeted therapies in neoadjuvant and adjuvant settings also require molecular characterisation for early-stage patients. Due to the widespread use of molecular analysis in patients with early-stage NSCLC, the prognostic role of molecular biomarkers needs to be fully understood. This paper aimed to review the most recent studies associating the molecular expressions of early-stage NSCLC with survival.

Abstract

Next-generation sequencing has become a cornerstone in clinical oncology practice and is recommended for the appropriate use of tailored therapies in NSCLC. While NGS has already been standardised in advanced-stage NSCLC, its use is still uncommon in the early stages. The recent approval of Osimertinib for resected EGFR-mutated NSCLC in an adjuvant setting has launched the hypothesis that other targeted therapies used in metastatic patients can also lead to improved early-stage outcomes of NSCLC. The impact of molecular biomarkers on the prognosis of patients undergoing radical surgery for NSCLC is still unclear. Notably, the heterogeneous populations included in the studies that analysed surgical patients could be the main reason for these results. In this review, we report the most important studies that analysed the impact of principal molecular biomarkers on the survival outcomes of patients who underwent radical surgery for NSCLC.

Update on adjuvant therapy in completely resected NSCLC patients

In patients with completely resected non‐small cell lung cancer (NSCLC), postoperative adjuvant chemotherapy has been associated with improvement in survival by minimizing the risk of recurrence. For years, systemic chemotherapy including platinum based regimen has been a mainstay treatment modality of adjuvant treatment after complete resection. ADAURA study showed that among completely resected IB to IIIA NSCLC, disease‐free survival was significantly better in patients under adjuvant osimertinib than a placebo group. After the advent of a variety of new treatment regimens, such as third generation TKI and immunotherapy, the landscape of postoperative adjuvant treatment has been changing. In this review, we discuss some key issues regarding choice of adjuvant treatment after complete resection in NSCLC, and provide further updates on recent advances in treatment modalities.