Clonality and prognostic implications of p53 and epidermal growth factor receptor somatic aberrations in multiple primary lung cancers

From Morphology to Molecules: Advances in the Distinction of Multiple Primary Lung Cancers From Intrapulmonary Metastases in Non-Small Cell Lung Cancer

The increasing incidence of multiple lung nodules underscores the need for precise differentiation between multiple primary lung cancers (MPLCs) and intrapulmonary metastases (IPMs). This distinction impacts patient prognosis and treatment strategies. The prevalence of multiple lung nodules, ranging from 19.7% to 55.5%, highlights the clinical significance of this challenge. Historically, the role of histopathology, particularly comprehensive histology assessment (CHA), has been pivotal in differentiating MPLCs and IPMs. However, CHA has significant limitations, resulting in a constant search for a better way to distinguish those lesions. The best strategy for delineating MPLCs from IPMs is a multidisciplinary approach combining clinical data, radiology, histology, and molecular methods. Histology provides architectural and cellular characteristics, radiology contributes anatomic context and lesion characterization, and molecular methods reveal molecular features critical for accurate differentiation. Incorporating clinical data further enhances diagnostic precision. This review presents current knowledge and current approaches to multiple lung tumors. It is clear that even with a combination of pathology, radiology, and molecular data, definitive classification of multifocal lung tumors is not always possible.

Classification of multiple primary lung cancer in patients with multifocal lung cancer: assessment of a machine learning approach using multidimensional genomic data

Background

Multiple primary lung cancer (MPLC) is an increasingly well-known clinical phenomenon. However, its molecular characterizations are poorly understood, and still lacks of effective method to distinguish it from intrapulmonary metastasis (IM). Herein, we propose an identification model based on molecular multidimensional analysis in order to accurately optimize treatment.

Methods

A total of 112 Chinese lung cancers harboring at least two tumors (n = 270) were enrolled. We retrospectively selected 74 patients with 121 tumor pairs and randomly divided the tumor pairs into a training cohort and a test cohort in a 7:3 ratio. A novel model was established in training cohort, optimized for MPLC identification using comprehensive genomic profiling analyzed by a broad panel with 808 cancer-related genes, and evaluated in the test cohort and a prospective validation cohort of 38 patients with 112 tumors.

Results

We found differences in molecular characterizations between the two diseases and rigorously selected the characterizations to build an identification model. We evaluated the performance of the classifier using the test cohort data and observed an 89.5% percent agreement (PA) for MPLC and a 100.0% percent agreement for IM. The model showed an excellent area under the curve (AUC) of 0.947 and a 91.3% overall accuracy. Similarly, the assay achieved a considerable performance in the independent validation set with an AUC of 0.938 and an MPLC predictive value of 100%. More importantly, the MPLC predictive value of the classification achieved 100% in both the test set and validation cohort. Compared to our previous mutation-based method, the classifier showed better κ consistencies with clinical classification among all 112 patients (0.84 vs. 0.65, p <.01).

Conclusion

These data provide novel evidence of MPLC-specific genomic characteristics and demonstrate that our one-step molecular classifier can accurately classify multifocal lung tumors as MPLC or IM, which suggested that broad panel NGS may be a useful tool for assisting with differential diagnoses.

Bilateral synchronous double primary lung cancer: A case report

Key Clinical Message

Bilateral synchronous double primary lung cancer (sDPLC) is a rare disease in clinics. This study analyzed the clinical data of a patient with bilateral sDPLC, aiming to improve medical workers' understanding of the disease and avoid missed diagnosis and misdiagnosis.

Abstract

A 68-year-old male was admitted to the hospital with "intermittent cough and expectoration for two months." Enhanced chest computed tomography (CT) showed that the upper lobe of the left lung had a mass of high-density shadow, bronchial opening of the left lobe was thickened, lumen was narrow, and middle lobe of the right lung had a mass of high-density shadow. Bronchoscopy was performed to observe the microscopic characteristics of the lesions in the upper lobe of the left lung, and abnormal mucosa was biopsied. The pathological and immunohistochemical results confirmed that it was small cell lung cancer (SCLC) in the upper lobe of the left lung. Considering the occupation of the middle lobe of the right lung, CT-guided lung biopsy was performed, and the pathological and immunohistochemical results confirmed that it was moderately differentiated squamous cell carcinoma (SCC) in the middle lobe of the right lung. Clinicians should strengthen their understanding of sDPLC and focus on the imaging characteristics of chest CT and performance under bronchoscopy. Additionally, it is necessary to perform both CT-guided lung biopsy and bronchoscopy to obtain histopathological findings for the diagnosis.

Genomic alterations in oral multiple primary cancers

Oral squamous cell carcinoma (OSCC) is the predominant type of oral cancer, while some patients may develop oral multiple primary cancers (MPCs) with unclear etiology. This study aimed to investigate the clinicopathological characteristics and genomic alterations of oral MPCs. Clinicopathological data from patients with oral single primary carcinoma (SPC, n = 202) and oral MPCs (n = 34) were collected and compared. Copy number alteration (CNA) analysis was conducted to identify chromosomal-instability differences among oral MPCs, recurrent OSCC cases, and OSCC patients with lymph node metastasis. Whole-exome sequencing was employed to identify potential unique gene mutations in oral MPCs patients. Additionally, CNA and phylogenetic tree analyses were used to gain preliminary insights into the molecular characteristics of different primary tumors within individual patients. Our findings revealed that, in contrast to oral SPC, females predominated the oral MPCs (70.59%), while smoking and alcohol use were not frequent in MPCs. Moreover, long-term survival outcomes were poorer in oral MPCs. From a CNA perspective, no significant differences were observed between oral MPCs patients and those with recurrence and lymph node metastasis. In addition to commonly mutated genes such as CASP8, TP53 and MUC16, in oral MPCs we also detected relatively rare mutations, such as HS3ST6 and RFPL4A. Furthermore, this study also demonstrated that most MPCs patients exhibited similarities in certain genomic regions within individuals, and distinct differences of the similarity degree were observed between synchronous and metachronous oral MPCs.

Macrophage migration inhibitory factor may contribute to the occurrence of multiple primary lung adenocarcinomas

BACKGROUND

This study aimed to identify the key genes involved in the development of multiple primary lung cancers.

METHODS

Differential expression analysis was performed, followed by comparing the infiltration levels of 22 immune cell types between multiple and single primary lung adenocarcinomas. Marker genes for epithelial cells with different proportions between the two types of lung adenocarcinomas were identified. The common genes between the marker genes and differentially expressed genes were identified. Finally, the effects of the key genes were tested on the in vitro proliferation, migration and morphology.

RESULTS

The infiltration levels of helper follicular T cells, resting NK cells, activated NK cells, M2 macrophages and resting mast cells were higher in the patients with multiple than in those with single primary lung adenocarcinomas. A total of 1553 differentially expressed genes and 4414 marker genes of epithelial cells were identified. Logistic regression analysis was performed on the 164 resulting genes. The macrophage migration inhibitory factor expression was positively associated with the occurrence of multiple primary lung adenocarcinomas. Moreover, its signalling pathway was the key pathway among the epithelial cells and multiple and single primary lung adenocarcinoma cells, and it was upregulated in lung adenocarcinoma cells. It also increased the expression of lung cancer markers, including NES and CA125, induced morphological changes in alveolar epithelial type II cells, and promoted their proliferation, migration and invasion.

CONCLUSIONS

Multiple and single primary lung adenocarcinomas have different tumour immune microenvironments, and migration inhibitory factor may be a key factor in the occurrence of multiple primary lung adenocarcinomas.

Lineage tracing for multiple lung cancer by spatiotemporal heterogeneity using a multi-omics analysis method integrating genomic, transcriptomic, and immune-related features

Introduction

The distinction between multiple primary lung cancer (MPLC) and intrapulmonary metastasis (IPM) holds clinical significance in staging, therapeutic intervention, and prognosis assessment for multiple lung cancer. Lineage tracing by clinicopathologic features alone remains a clinical challenge; thus, we aimed to develop a multi-omics analysis method delineating spatiotemporal heterogeneity based on tumor genomic profiling.

Methods

Between 2012 and 2022, 11 specimens were collected from two patients diagnosed with multiple lung cancer (LU1 and LU2) with synchronous/metachronous tumors. A novel multi-omics analysis method based on whole-exome sequencing, transcriptome sequencing (RNA-Seq), and tumor neoantigen prediction was developed to define the lineage. Traditional clinicopathologic reviews and an imaging-based algorithm were performed to verify the results.

Results

Seven tissue biopsies were collected from LU1. The multi-omics analysis method demonstrated that three synchronous tumors observed in 2018 (LU1B/C/D) had strong molecular heterogeneity, various RNA expression and immune microenvironment characteristics, and unique neoantigens. These results suggested that LU1B, LU1C, and LU1D were MPLC, consistent with traditional lineage tracing approaches. The high mutational landscape similarity score (75.1%), similar RNA expression features, and considerable shared neoantigens (n = 241) revealed the IPM relationship between LU1F and LU1G which were two samples detected simultaneously in 2021. Although the multi-omics analysis method aligned with the imaging-based algorithm, pathology and clinicopathologic approaches suggested MPLC owing to different histological types of LU1F/G. Moreover, controversial lineage or misclassification of LU2's synchronous/metachronous samples (LU2B/D and LU2C/E) traced by traditional approaches might be corrected by the multi-omics analysis method. Spatiotemporal heterogeneity profiled by the multi-omics analysis method suggested that LU2D possibly had the same lineage as LU2B (similarity score, 12.9%; shared neoantigens, n = 71); gefitinib treatment and EGFR, TP53, and RB1 mutations suggested the possibility that LU2E might result from histology transformation of LU2C despite the lack of LU2C biopsy and its histology. By contrast, histological interpretation was indeterminate for LU2D, and LU2E was defined as a primary or progression lesion of LU2C by histological, clinicopathologic, or imaging-based approaches.

Conclusion

This novel multi-omics analysis method improves the accuracy of lineage tracing by tracking the spatiotemporal heterogeneity of serial samples. Further validation is required for its clinical application in accurate diagnosis, disease management, and improving prognosis.

Towards the molecular era of discriminating multiple lung cancers

In the era of histopathology-based diagnosis, the discrimination between multiple lung cancers (MLCs) poses significant uncertainties and has thus become a clinical dilemma. However, recent significant advances and increased application of molecular technologies in clonal relatedness assessment have led to more precision in distinguishing between multiple primary lung cancers (MPLCs) and intrapulmonary metastasis (IPMs). This review summarizes recent advances in the molecular identification of MLCs and compares various methods based on somatic mutations, chromosome alterations, microRNAs, and tumor microenvironment markers. The paper also discusses current challenges at the forefront of genomics-based discrimination, including the selection of detection technology, application of next-generation sequencing, and intratumoral heterogeneity (ITH). In summary, this paper highlights an entrance into the primary stage of molecule-based diagnostics.

Multiple primary lung cancer: Updates of clinical management and genomic features

In recent decades, multiple primary lung cancer (MPLC) has been increasingly prevalent in clinical practice. However, many details about MPLC have not been completely settled, such as understanding the driving force, clinical management, pathological mechanisms, and genomic architectures of this disease. From the perspective of diagnosis and treatment, distinguishing MPLC from lung cancer intrapulmonary metastasis (IPM) has been a clinical hotpot for years. Besides, compared to patients with single lung lesion, the treatment for MPLC patients is more individualized, and non-operative therapies, such as ablation and stereotactic ablative radiotherapy (SABR), are prevailing. The emergence of next-generation sequencing has fueled a wave of research about the molecular features of MPLC and advanced the NCCN guidelines. In this review, we generalized the latest updates on MPLC from definition, etiology and epidemiology, clinical management, and genomic updates. We summarized the different perspectives and aimed to offer novel insights into the management of MPLC.

Multiple Primary Lung Cancers With ALK Rearrangement: A Case Report and Literature Review

Multiple primary lung cancers (MPLCs) are that patients with lung cancer may present with two primary tumors at the same time (synchronous multiple primary lung cancer, SMPLC) or may develop a second, metachronous primary lung cancer after treatment of the initial lesion. Currently, there are no definitive guidelines for the diagnosis and treatment of multiple primary lung cancers. Herein, we report a case of double primary lung cancers with ALK rearrangement. The patient was treated with chemotherapy, targeted therapy, and radiotherapy. After these treatments, the patient was free of locally recurrent or distant disease at 2 years.

Whole-Process Treatment of Combined Small Cell Lung Cancer Initially Diagnosed as "Lung Squamous Cell Carcinoma": A Case Report and Review of the Literature

The rarity and complexity of histology lead to the low diagnosis rate and high misdiagnosis rate of combined small cell lung cancer (C-SCLC). Nowadays, C-SCLC has no commonly recommended therapeutic regimen, mainly conforming to SCLC treatment. Here, we report a patient initially diagnosed as IIIA "lung squamous cell carcinoma" by a small specimen. Radical resection was achieved after neoadjuvant immunochemotherapy, and the final surgical pathology was C-SCLC containing three different histological components. Moreover, in the literature review, we explored the therapeutic effect of neoadjuvant immunotherapy in C-SCLC, expounded the therapeutic conflicts among heterogeneous components, and analyzed the pathology complexity at the tissue, cell, and molecule levels in-depth, including possible genetic characteristics, origin, and evolution by next-generation sequencing (NGS).

EGFR mutation status in non-small cell lung cancer receiving PD-1/PD-L1 inhibitors and its correlation with PD-L1 expression: a meta-analysis

Meta-analysis was performed on the Web of Science, PubMed, Embase, and Cochrane databases to evaluate the effect of epidermal growth factor receptor (EGFR) mutation status on programmed cell death protein 1/programmed death ligand 1 (PD-1/PD-L1) immune checkpoint inhibitors, and the association between EGFR mutation status and PD-L1 expression in non-small cell lung cancer (NSCLC) patients. Pooled effect (hazard ratio/odds ratio, HR/OR) with 95% confidence interval (CI) was calculated, and the source of heterogeneity was explored by subgroup analysis and meta-regression using Stata/SE 15.0. Meta-analysis of the association between EGFR mutation status and overall survival (OS) in NSCLC with immunotherapy was calculated from four randomized controlled trials. We found that immune checkpoint inhibitors significantly prolonged OS over docetaxel overall (HR 0.71, 95% CI 0.64-0.79) and in the EGFR wild type (HR = 0.67, 95% CI = 0.60-0.75), but not in the EGFR mutant subgroup (HR = 1.11, 95% CI = 0.80-1.52). Meta-analysis of the association between EGFR mutation status and PD-L1 expression in NSCLC included 32 studies. The pooled OR and 95% CI were 0.60 (0.46-0.80), calculated by random effects model. No source of heterogeneity was found in subgroup analysis. Sensitivity analysis was carried out with a fixed model, and the influence of a single study on the pooled results showed no significant change with robust meta-analysis methods. Harbord's weighted linear regression test (P = 0.956) and Peters regression test (P = 0.489) indicated no significant publication bias. The limited benefit of single-agent PD-1/PD-L1 inhibitors in the second-line or later setting for EGFR-mutated NSCLC may be partly due to the lower expression of PD-L1.

A case of haemoptysis and bilateral areas of lung consolidation sparing the right lower lobe

Multiple primary lung cancers (MPLC) are often neglected. Obtaining pre-operative specimens through bronchoscopy could play a role. It is important to distinguish aerogenous metastasis from MPLC in the adenocarcinoma spectrum due to the different prognosis.https://bit.ly/3zbdVrw

Recent Advances in the Diagnosis and Management of Multiple Primary Lung Cancer

With the wide application of computed tomography in lung cancer screening, the incidence of multiple primary lung cancer (MPLC) has been increasingly reported. Despite the established criteria, the differentiation between MPLC and intrapulmonary metastasis remains challenging. Although histologic features are helpful in some circumstances, a molecular analysis is often needed. The application of next-generation sequencing could aid in distinguishing MPLCs from intrapulmonary metastasis, decreasing ambiguity. For MPLC management, surgery with lobectomy is the main operation method. Limited resection does not appear to negatively affect survival, and it is a reasonable alternative. Stereotactic ablative radiotherapy (SABR) has become a standard of care for patients refusing surgery or for those with medically inoperable early-stage lung cancer. However, the efficacy of SABR in MPLC management could only be found in retrospective series. Other local ablation techniques are an emerging alternative for the control of residual lesions. Furthermore, systemic therapies, such as targeted therapy for oncogene-addicted patients, and immunotherapy have shown promising results in MPLC management after resection. In this paper, the recent advances in the diagnosis and management of MPLC are reviewed.

The Role of Whole Exome Sequencing in Distinguishing Primary and Secondary Lung Cancers

Non-small cell lung cancer (NSCLC) that presents with multiple lung tumors (MLTs) poses a challenge to accurate staging and prognosis. MLTs that arise as clonally related secondary metastases from a common primary are higher stage and often require adjuvant chemotherapy or may in fact be incurable stage IV lesions. Conversely, MLTs that represent distinct primaries have a better prognosis and may be overtreated if inappropriately classified as related secondaries. Historically, pathologic and radiographic criteria were used to distinguish between primary and secondary MLTs; however, the advent of genomic profiling has demonstrated limitations to these historic classification systems. In this review, we discuss the use of molecular profiling to distinguish between primary and secondary lung cancers, with a focus on the insights gleaned from whole exome sequencing (WES) analyses. While WES is not yet feasible in routine clinical practice, WES studies have helped elucidate the clonal relationship between primary and secondary lung cancers and provide important context for the application of targeted sequencing panel-based analyses.

Molecular Identification and Genetic Characterization of Early-Stage Multiple Primary Lung Cancer by Large-Panel Next-Generation Sequencing Analysis

Objective

The incidence of early stage multiple primary lung cancer (MPLC) has been increasing in recent years, while the ideal strategy for its diagnosis and treatment remains controversial. The present study conducted genomic analysis to identify a new molecular classification method for accurately predicting the diagnosis and therapy for patients with early stage MPLC.

Methods

A total of 240 tissue samples from 203 patients with multiple-non-small-cell lung cancers (NSCLCs) (n = 30), early stage single-NSCLC (Group A, n = 94), and advanced-stage NSCLC (Group B, n = 79) were subjected to targeted multigene panel sequencing.

Results

Thirty patients for whom next-generation sequencing was performed on >1 tumor were identified, yielding 45 tumor pairs. The frequencies of EGFR, TP53, RBM10, ERBB2, and CDKN2A mutations exhibited significant differences between early and advanced-stage NSCLCs. The prevalence of the EGFR L858R mutation in early stage NSCLC was remarkably higher than that in advanced-stage NSCLC (P = 0.047). The molecular method classified tumor pairs into 26 definite MPLC tumors and four intrapulmonary metastasis (IM) tumors. A high rate of discordance in driver genetic alterations was found in the different tumor lesions of MPLC patients. The prospective Martini histologic prediction of MPLC was discordant with the molecular method for three patients (16.7%), particularly in the prediction of IM (91.7% discordant).

Conclusions

Comprehensive molecular evaluation allows the unambiguous delineation of clonal relationships among tumors. In comparison, the Martini and Melamed criteria have notable limitations in the recognition of IM. Our results support the adoption of a large panel to supplement histology for strongly discriminating NSCLC clonal relationships in clinical practice.

Genomic and Clinical Significance of Multiple Primary Lung Cancers as Determined by Next-Generation Sequencing

INTRODUCTION

Marked variations in survival rates have brought into question whether standard clinicopathologic classification should be applied to patients presenting with multiple primary lung cancers (MPLCs). This study investigated the genetic profiles of MPLCs in a cohort of patients using next-generation sequencing and correlated results to clinicopathologic data and patient outcome.

METHODS

Patients treated surgically with curative intent for two putative primaries of similar histopathology from January 2000 to December 2019 at St Vincent's Hospital Melbourne. DNA and RNA was extracted from formalin-fixed, paraffin-embedded tumor tissue and sequenced on an Ion Torrent Personal Genome Machine system. Patient outcome was determined by overall survival and disease-free survival.

RESULTS

A total of 40 cases fulfilled the inclusion criteria. Mutational profiling was concordant with clinicopathologic diagnosis in most cases; however, seven cases (17.5%) revealed shared mutations suggesting metastatic disease and this was associated with a substantial reduction in overall survival (p < 0.05).

CONCLUSIONS

Our results suggest that gene sequencing technologies are potentially a more accurate diagnostic and prognostic tool compared with traditional histopathologic evaluation in patients presenting with suspected MPLCs, which could better guide management and predict outcomes.

Synchronous Multiple Lung Cancers with Lymph Node Metastasis and Different EGFR Mutations: Intrapulmonary Metastasis or Multiple Primary Lung Cancers?

Background

There is no consensus on whether patients with synchronous multiple lung cancers (SMLC) who present with lymph node metastasis (LNM) but whose epidermal growth factor receptor (EGFR) mutations are different are considered to have intrapulmonary metastases or multiple primary lung cancers. Few studies on these patients have been reported.

Methods

The electronic medical records of patients with surgically resected multiple lung cancers between February 2016 and July 2019 were retrospectively reviewed, focusing on the clinical characteristics and prognosis of patients with LNM and different EGFR mutations.

Results

A total of 125 patients were diagnosed with SMLC, and only 8 patients had LNM and different EGFR mutations. Their mean age was 61.43 ± 8.08 years (range 47–69 years). EGFR detection suggested that 4 patients had completely different mutation types, and 4 patients had mutations in only 1 tumor. Only 1 of the 17 total lesions was squamous cell carcinoma, the rest were adenocarcinoma. All patients underwent adjuvant therapy after surgery. Except for 1 patient who underwent chemotherapy, the rest received tyrosine kinase inhibitor-targeted therapy. As at 15 October 2020, the average follow-up time was 28.68 ± 10.74 months (range 10.5–40.5 months), and all patients were alive except 1 who died from extensive pleural metastasis.

Conclusion

The current study highlights the clinical importance of EGFR detection in SMLC, especially in patients with LNM. SMLC with LNM and different EGFR mutations should be considered multiple primary lung cancers rather than intrapulmonary metastases, and comprehensive treatment based on surgery may be preferable in these patients due to a good prognosis.

Multiple Primary Lung Cancers: A New Challenge in the Era of Precision Medicine

With the widespread implementation of lung cancer screening, more and more patients are being diagnosed with multiple primary lung cancers (MPLCs). In the era of precision medicine, many controversies remain in differentiating MPLCs from intrapulmonary metastasis and the optimum treatment choice, especially in patients exhibiting similar histology. In this review, we summarize common diagnostic criteria and novel discrimination methods with a special emphasis on the emerging value of broad panel next-generation sequencing (NGS) for the diagnosis of MPLCs. We then discuss current advances regarding therapeutic approaches for MPLCs. Radical surgery is the main treatment modality, while stereotactic body radiotherapy (SBRT) is safe and feasible for early-stage MPLC patients with inoperable tumors. In addition, immunotherapy and targeted therapy, particularly epidermal growth factor receptor-tyrosine kinase inhibitors, are emerging therapeutic strategies that are still in their infancy. Characteristics of both genomic profiles and tumor microenvironment are currently being evaluated but warrant further exploration to facilitate the application of targeted systematic therapies in MPLC patients.

Differentiating synchronous double primary lung adenocarcinomas from intrapulmonary metastasis by CT features, EGFR mutations and ALK rearrangement status

Background

Differentiating synchronous double primary lung adenocarcinoma (SDPLA) from interpulmonary metastasis (IPM) has significant therapeutic and prognostic implications. This retrospective study aimed to investigate the potential of computed tomography (CT) features and two known oncogenic driver mutations [epidermal growth factor receptor (EGFR) and anaplastic large-cell lymphoma kinase (ALK)] to discriminate synchronous double primary lung adenocarcinoma from one primary pulmonary adenocarcinoma with intrapulmonary metastasis.

Methods

Patients with SDPLA were selected at our hospital, and those with IPM served as the control group. All 60 patients (40 with SDPLA and 20 with IPM) were tested for EGFR mutations and ALK status, and they underwent chest CT prior to any treatment. Independent-sample Student's t-test was used for comparisons between two groups of normally distributed variables, and the Chi-square test was used to compare categorical variables.

Results

The discordance rate of EGFR mutations was significantly higher in patients with SDPLA than in patients with IPM (40% vs. 5%, P<0.001). The incidence of ALK-positive status was 15%, and patients with IPM were more likely to be ALK-positive than patients with SDPLA (35% vs. 5%, P<0.001). Compared to IPM, SDPLA more frequently occurred in different lobes (P=0.024), presented with less lymphadenopathy (P=0.014), showed a smaller difference in diameter (Äd) between tumors (P=0.001) and more commonly presented as lobulated tumors (P<0.001), spiculated masses (P<0.001), ground-glass opacities (GGOs) (P=0.001) and air bronchograms (P=0.020).

Conclusion

Patients with SDPLA showed higher discordance with EGFR mutations and were less frequently ALK-positive than those with IPM. Thus, the CT characteristics are significantly different between SDPLA and IPM.

Whole exome sequencing of lung adenocarcinoma and lung squamous cell carcinoma in one individual: A case report

Multiple primary lung cancers (MPLCs) refers to two or more primary malignant tumors that occur simultaneously or successively in the lung of the same patient. Distinguishing MPLCs from intrapulmonary metastases is important for treatment strategy and prognosis. MPLCs have been considered as having different origins and clonal evolutionary processes. Whole genome sequencing (WGS) and whole exome sequencing (WES) are regarded as an effective way to identify the relationship and differentiation among MPLC nodules. Here, we report the case of a 63‐year‐old MPLC male patient who smoked for 40 years. Two nodules were found on chest computed tomography (CT) scan, which were further confirmed by pathology to be lung adenocarcinoma (ADC) and lung squamous cell carcinoma (SCC), respectively. WES of the two different nodules was performed, and the results showed that there was a significant genetic difference between the two nodules. Further analysis of the tumor mutation burden (TMB) of the two tumor lesions showed that the TMB of the squamous cell carcinoma was higher than that of the adenocarcinoma, indicating that the squamous cell carcinoma had a higher mutation frequency. According to the pathology and WES sequencing results, MPLCs for this case were regarded as independent of each other, with different origins and clonal evolutionary processes. In this case report, we emphasize that WES should play an important role in determining the origin of MPLC clones, and also make some explorations for the further discovery of new potential driver genes and therapeutic targets.

Epidermal Growth Factor Receptor Mutation Frequency in Squamous Cell Carcinoma and Its Diagnostic Performance in Cytological Samples: A Molecular and Immunohistochemical Study

Background

Epidermal growth factor receptor (EGFR) mutation is the most frequent mutation tested in lung cancer for targeted therapy in the era of personalized medicine. Knowledge about EGFR mutation is constantly expanding regarding its frequency, clinicopathological association, advancements in testing methodology and sample requirement. We investigated EGFR mutation frequency in non-small cell lung cancer (NSCLC) in North Indian patients and evaluated its diagnostic performance in cytological samples.

Methods

Molecular EGFR testing was done in 250 cases of NSCLC by both real-time polymerase chain reaction (PCR) (Therascreen) and mutation-specific EGFR immunohistochemistry (IHC). Thirty cases had both cytology samples and biopsy including 20 pleural effusions and 10 fine-needle aspirates. EGFR mutation concordance between pleural effusion and biopsy was studied.

Results

EGFR mutation was overall 31.6% in NSCLC with 36.5% in adenocarcinoma and 15% in squamous cell carcinoma. L858R mutation accounted for 50.7% and DEL19 for 39.3% of total EGFR mutations. Complex mutations were seen in 2% of cases. Sensitivity of mutation-specific EGFR IHC was 48.3% and specificity was 92.3%. L858R showed higher sensitivity (55% vs. 33.3%) but similar specificity (93.2% vs. 91.3%) compared to DEL19. EGFR mutation was successful in 95% of pleural effusion and showed 83.3% concordance with tissue biopsy.

Conclusions

EGFR mutation frequency in North Indian patients was comparable to that of Asia-Pacific region and showed a similar pattern of histological distribution. EGFR mutation in squamous cell carcinomas is increasingly recognized which was 15% in our study. Mutation-specific EGFR IHC shows variable but generally low sensitivity and considering its significant pre- and post-analytical variables, it should be highly discouraged in patient management. Cytological samples may not only serve as suitable alternative but may be complementary to tissue biopsies.

Multiple primary lung cancer: a rising challenge

With the use of high-resolution chest imaging system and lung cancer screening program, patients with multiple primary lung cancers (MPLCs) are becoming a growing population in clinical practice worldwide. The diagnostic criteria for MPLCs has been established and modified by three major lung cancer research institutes. However, due to the fact that the differential diagnosis between MPLCs and a recurrence, metastatic, or satellite lesion arising from the original lesion remains ambiguous and confusing, there is still insufficient evidence to support a uniform guideline. Newly developed molecular and genomic methods have the potential to better define the relationship among multiple lesions and bring the possibility of targeted therapy. Surgical resection remains the first choice for the treatment of MPLCs and detailed strategy should be carefully planned taking characteristics of the tumor and status of patients into consideration. For those who are intolerant to surgery, a new technology called stereotactic body radiation therapy (SBRT) is now an optional therapeutic strategy. Furthermore, multiple GGOs are unique MPLCs that need special attentions in the clinical practice.

Chronic obstructive pulmonary disease and lung cancer: inter-relationships

PURPOSE OF REVIEW

Chronic obstructive pulmonary disease (COPD) is a well established risk factor for lung cancer. Newer studies reveal a myriad of other mechanisms, some proven and some putative, which may contribute to their association.

RECENT FINDINGS

There is an ever-growing bundle of evidence that suggests a close association between persistent chronic inflammation and lung cancer. A few potential targets of genetic susceptibility locus for COPD and lung cancer have been suggested. Better characterization of immune dysregulation and identification of signaling pathways may assist the development of strategies to reduce risk of developing lung cancer in patients with COPD. Current lung cancer screening strategies may exclude some patients at high risk of having lung cancer. Prospective studies indicate that a screening criterion that includes variables reflecting the severity of COPD may increase the sensitivity of the screening program and reduce 'over-diagnosis bias' of indolent lung cancers. Examples of such variables include the emphysema score generated from computed tomography scans and diffusion capacity for carbon monoxide derived from lung function tests.

SUMMARY

A better understanding of the inter-relationship between lung cancer pathogenesis and COPD has been described recently. Improving lung cancer screening strategies by incorporating markers of COPD severity has recently been proposed.

Novel perspective to evaluate the safety of segmentectomy: clinical significance of lobar and segmental lymph node metastasis in cT1N0M0 lung adenocarcinoma

OBJECTIVES

The regularity of intrapulmonary lobar and segmental lymph node (LSN) metastasis in cT1N0M0 stage lung adenocarcinoma remains unclear. Thus, segmentectomy with uncertain LSN metastatic status remains a potential oncological risk. We aimed to facilitate more accurate determination of N staging and filter more suitable cases for segmentectomy.

METHODS

A prospective study was performed from March 2014 to September 2016. A total of 196 patients diagnosed with cT1N0M0 stage lung adenocarcinoma were enrolled and received lobectomy together with mediastinal lymph node dissection. The intrapulmonary LSNs were dissected and classified as adjacent LSN or isolated LSN. The metastatic status of the LSNs together with the TNM staging were analysed. A comparison of the metastatic probability of isolated LSN was carried out considering the metastatic status of adjacent LSN, imaging features, smoking history, pathological subtypes, size of the lesions and serum level of tumour markers (carcinoembryonic antigen and Cyfra21-1).

RESULTS

Among the 196 cases enrolled, 152 were confirmed as pN0, 36 as pN1, 6 as pN1 + N2 and 2 as skip pN2. When the LSNs had not been dissected, the false-negative rate for N staging was 9.0% (15 of 167). Patients with adjacent LSN metastasis (P < 0.001), solid nodule (P = 0.001), non-lepidic predominant invasive adenocarcinoma (P < 0.001), nodules with maximum diameter larger than 2 cm (P < 0.001) and those with elevated serum carcinoembryonic antigen level (>5 ng/ml) (P = 0.005) had a higher isolated LSN metastasis rate. No significant difference in isolated LSN metastasis rate was found between groups with or without smoking history (P = 0.90) and with different serum Cyfra21-1 levels (P = 0.14).

CONCLUSIONS

Dissection of intrapulmonary LSNs reduces the false-negative rate of lymph node metastasis. Solid nodule, non-lepidic predominant invasive adenocarcinoma, lung adenocarcinoma larger than 2 cm in maximum diameter or with elevated serum carcinoembryonic antigen level (>5 ng/ml) might not be suitable for segmentectomy. The lymph node sampling area during segmentectomy should include adjacent LSNs of the target segment. When metastasis to the adjacent LSNs is confirmed by fast-frozen pathology, segmentectomy would not be suitable.

Clonality assessment of multifocal lung adenocarcinoma by pathology evaluation and molecular analysis

The aim of this study was to explore morphologic and molecular features distinguishing between multifocal lung adenocarcinoma (MLA) and intrapulmonary metastases (IMs). Sixteen patients with MLAs, a total of 34 tumors, were reviewed. Four approaches were used: (1) array-comparative genomic hybridization (CGH) as a standard clonality assessment; (2) EGFR and KRAS mutational profiles as a supplementary method; (3) comprehensive histologic assessment (CHA) was method I in pathology evaluation; and (4) CHA combined with lepidic component analysis was method II. The lepidic component was divided into low grade and high grade according to extent of atypia; tumors with low-grade lepidic component were defined as primary. Eight patients were found to have IMs and 8 to have multiple primaries (MPs) by array-CGH; 7 had MPs and 9 had IMs by method I; 5 had MPs and 11 had IMs by method II. Compared with array-CGH, method I had a lower coincidence rate (65%) than method II (85%). Univariate analysis revealed that patients with MP had a better clinical outcome than those with IM only if the MPs were diagnosed by array-CGH (P = .034) or method II (P = .027) but not EGFR/KRAS mutation (P = .843) or method I (P = .493). Our results suggest that a low-grade lepidic component is a sign of a primary tumor. CHA combined with a low-grade lepidic component (method II) is more accurate clinically and more cost-effective in distinguishing MLAs from IMs. Also, EGFR mutation is not an appropriate molecular marker for clonality assessment.

Mutational analysis of multiple lung cancers: Discrimination between primary and metastatic lung cancers by genomic profile

In cases of multiple lung cancers, individual tumors may represent either a primary lung cancer or both primary and metastatic lung cancers. Treatment selection varies depending on such features, and this discrimination is critically important in predicting prognosis. The present study was undertaken to determine the efficacy and validity of mutation analysis as a means of determining whether multiple lung cancers are primary or metastatic in nature. The study involved 12 patients who underwent surgery in our department for multiple lung cancers between July 2014 and March 2016. Tumor cells were collected from formalin-fixed paraffin-embedded tissues of the primary lesions by using laser capture microdissection, and targeted sequencing of 53 lung cancer-related genes was performed. In surgically treated patients with multiple lung cancers, the driver mutation profile differed among the individual tumors. Meanwhile, in a case of a solitary lung tumor that appeared after surgery for double primary lung cancers, gene mutation analysis using a bronchoscopic biopsy sample revealed a gene mutation profile consistent with the surgically resected specimen, thus demonstrating that the tumor in this case was metastatic. In cases of multiple lung cancers, the comparison of driver mutation profiles clarifies the clonal origin of the tumors and enables discrimination between primary and metastatic tumors.

Association between PD-L1 expression and driver gene status in non-small-cell lung cancer: a meta-analysis

OBJECTIVE

To assess the association between PD-L1 expression and driver gene mutations in patients with non-small-cell lung cancer (NSCLC).

METHOD

We performed a meta-analysis of 26 studies (7541 patients) which were published from 2015 to 2017. Pooled odds ratios (ORs) with 95% confidence intervals (CI) were calculated to describe the correlation. Subgroup analysis was performed based on population characteristics, types of PD-L1 antibodies and quality of individual studies.

RESULTS

A lower frequency of PD-L1 positivity was observed in NSCLCs harboring EGFR mutation (OR: 0.64, 95% CI, 0.45-0.91, p = 0.014). A negative correlation was also found at 1% (OR: 0.35, 95% CI, 0.22-0.55, p = 0.000) and 50% (OR: 0.33, 95% CI, 0.14-0.81, p = 0.015) cutoff for PD-L1 positive, elderly age group (OR: 0.56, 95% CI, 0.35-0.89, p = 0.013), female dominant group (OR: 0.55, 95% CI, 0.29-0.94, p = 0.030) and smoker dominant group (OR: 0.52, 95% CI, 0.29-0.96, p = 0.035). No significant differences in PD-L1 expression were observed among patients with different ALK, BRAF, HER2, PIK3CA status and MET expression level. Higher level of PD-L1 was found in tumors with KRAS mutation (OR: 1.45, 95% CI, 1.18-1.80, p = 0.001). PD-L1 expression level was not significantly different between triple (EGFR/ALK/KRAS) wild type NSCLCs and those with EGFR/ALK/KRAS mutation.

CONCLUSIONS

PD-L1 expression in EGFR mutated NSCLCs were lower than those in EGFR wild type NSCLCs, while tumors with KRAS mutation showed higher levels of PD-L1.

An evolutionary perspective on field cancerization

Tumorigenesis begins long before the growth of a clinically detectable lesion and, indeed, even before any of the usual morphological correlates of pre-malignancy are recognizable. Field cancerization, which is the replacement of the normal cell population by a cancer-primed cell population that may show no morphological change, is now recognized to underlie the development of many types of cancer, including the common carcinomas of the lung, colon, skin, prostate and bladder. Field cancerization is the consequence of the evolution of somatic cells in the body that results in cells that carry some but not all phenotypes required for malignancy. Here, we review the evidence of field cancerization across organs and examine the biological mechanisms that drive the evolutionary process that results in field creation. We discuss the clinical implications, principally, how measurements of the cancerized field could improve cancer risk prediction in patients with pre-malignant disease.

[Clinical and Prognosic Anylasis of 30 Cases with Double Primary Lung Cancer]

背景与目的

多原发肺癌（multiple primary lung cancer, MPLC）是一种临床中较为少见的肺癌类型，双原发肺癌（double primary lung cancer, DPLC）是其中最常见的一种，近年来由于诊疗手段的进步检出率逐渐升高。本研究总结分析了30例DPLC患者的临床资料，以期为DPLC的诊疗提供理论依据。

方法

回顾郑州大学附属肿瘤医院2010年1月-2015年12月收治的30例DPLC患者的临床资料，对临床特征及预后相关因素进行分析。

结果

30例中，同时性双原发癌（synchronous DPLC, sDPLC）占3例（3/30, 10%），异时性双原发癌（metachronous DPLC, mDPLC）占27例（27/30, 90.0%）。病灶好发于右肺上叶（20/60, 33.3%），病理类型以腺癌（25/60, 41.7%）为主，病理类型相同者（17/30, 56.7%）多于不同者（13/30, 43.3%），病理类型相同者以腺-腺（10/16, 62.5%）最常见。生存分析显示淋巴结转移（HR=4.349, 95%CI: 1.435-13.178, P=0.009）和重度吸烟史（HR=2.996, 95%CI: 1.089-8.240, P=0.034）是DPLC的不良预后因素。

结论

DPLC好发于右肺上叶，病理类型以腺癌为主，早期诊断、积极的治疗和严格的戒烟策略有望改善其预后。

Triple synchronous primary lung cancer: a case report and review of the literature

Background

Multiple primary lung cancer may present in synchronous or metachronous form. Synchronous multiple primary lung cancer is defined as multiple lung lesions that develop at the same time, whereas metachronous multiple primary lung cancer describes multiple lung lesions that develop at different times, typically following treatment of the primary lung cancer. Patients with previously treated lung cancer are at risk for developing metachronous lung cancer, but with the success of computed tomography and positron emission tomography, the ability to detect both synchronous and metachronous lung cancer has increased.

Case presentation

We present a case of a 63-year-old Hispanic man who came to our hospital for evaluation of chest pain, dry cough, and weight loss. He had recently been diagnosed with adenocarcinoma in the right upper lobe, with a poorly differentiated carcinoma favoring squamous cell cancer based on bronchoalveolar lavage of the right lower lobe for which treatment was started. Later, bronchoscopy incidentally revealed the patient to have an endobronchial lesion that turned out to be mixed small and large cell neuroendocrine lung cancer. Our patient had triple synchronous primary lung cancers that histologically were variant primary cancers.

Conclusions

Triple synchronous primary lung cancer management continues to be a challenge. Our patient’s case suggests that multiple primary lung cancers may still occur at a greater rate than can be detected by high-resolution computed tomography.

Clinical Significance and Next-Generation Sequencing of Chinese Pulmonary Sarcomatoid Carcinoma

Pulmonary Sarcomatoid Carcinoma (PSC) constitutes a heterogeneous group of non-small-cell lung carcinomas (NSCLCs) with a poor prognosis. In this study, a group of 7 patients with PSC was studied. Microscope analysis of all 7 cases revealed a pleomorphic carcinoma subtype. Moreover, 5 cases (71.4%) were composed entirely of malignant sarcomatoid-like elements, and 2 cases (28.6%) were composed of malignant sarcomatoid-like elements and at least 10% adenocarcinoma-like elements. Immunohistochemically, the PSC components of all 7 cases were positive for vimentin and cytokeratins, including cytokeratin (CK) and cytokeratin 7 (CK7). Next-Generation Sequencing (NGS) was performed, and a total of 136 putative somatic variants and one gene fusion were identified, of which 16 variants were considered hot spot mutations, including the genes EGFR, EML4-ALK, MET, BRAF, PIK3CA, and TP53. Of these hot spot mutations, one sample expressing an EML4-ALK fusion was further confirmed by Ventana IHC, and one sample containing an EGFR exon 19 deletion was also confirmed. The NGS results imply that TP53 mutations occur often in PSCs and that EML4-ALK fusion events and EGFR exon deletions also occur in these rare tumors. Molecular targeted therapy may be a useful treatment strategy for these rare lung tumors.

Synchronous mucinous and non-mucinous lung adenocarcinomas with different epidermal growth mutational status

In recent years, the spread of more-sensitive diagnostic methods has resulted in an increase of synchronous multiple primary lung cancer diagnosis. Nevertheless, its occurrence is still rare. Distinction between synchronous lesions from second independent primary tumors is a problem when dealing with multiple lung tumors, particularly if the histological type is the same. We present a case report of a 78-year-old female patient referred to our institution due to pneumonia. A subsequent thoracic computed tomography (CT) was performed showing two suspicious lesions, one in the right upper lobe and the other in the right inferior lobe. The CT-guided transthoracic needle biopsy of both pulmonary lesions revealed two adenocarcinomas, but with a rare combination of distinct morphologic variants, as well as different immunophenotypes and epidermal growth factor receptor (EGFR) gene status. The patient refused surgery and was submitted to stereotactic body radiation therapy (SBRT). She maintained tight follow-up and until now, she has not shown any signs of relapse or metastasis. A multidisciplinary approach with clinical, morphologic and molecular evaluation in multiple lung cancer is important to diagnosis and treatment guidance.

[Research Progress in Diagnosis and Management Strategies of Multiple Primary Lung Cancer]

原发肺癌（multiple primary lung cancer, MPLC）的发病率呈逐年上升趋势，但关于MPLC的发病机制、诊断、鉴别诊断和临床处理策略仍存在诸多争议。本综述将对目前关于MPLC的发病机制、诊断标准、鉴别诊断和处理策略方面的研究进展做一个回顾，旨在为该病的诊疗提供理论基础。

Utility of Genomic Analysis in Differentiating Synchronous and Metachronous Lung Adenocarcinomas from Primary Adenocarcinomas with Intrapulmonary Metastasis

Distinguishing synchronous and metachronous primary lung adenocarcinomas from adenocarcinomas with intrapulmonary metastasis is essential for optimal patient management. In this study, multiple lung adenocarcinomas occurring in the same patient were evaluated using comprehensive histopathologic evaluation supplemented with molecular analysis. The cohort included 18 patients with a total of 52 lung adenocarcinomas. Eleven patients had a new diagnosis of multiple adenocarcinomas in the same lobe (n = 5) or different lobe (n = 6). Seven patients had a history of lung cancer and developed multiple new tumors. The final diagnosis was made in resection specimens (n = 49), fine needle aspiration (n = 2), and biopsy (n = 1). Adenocarcinomas were non‐mucinous, and histopathologic comparison of tumors was performed. All tumors save for one were subjected to ALK gene rearrangement testing and targeted Next Generation Sequencing (NGS). Using clinical, radiologic, and morphologic features, a confident conclusion favoring synchronous/metachronous or metastatic disease was made in 65% of patients. Cases that proved challenging included ones with more than three tumors showing overlapping growth patterns and lacking a predominant lepidic component. Genomic signatures unique to each tumor were helpful in determining the relationship of multiple carcinomas in 72% of patients. Collectively, morphologic and genomic data proved to be of greater value and achieved a conclusive diagnosis in 94% of patients. Assessment of the genomic profiles of multiple lung adenocarcinomas complements the histological findings, enabling a more comprehensive assessment of synchronous, metachronous, and metastatic lesions in most patients, thereby improving staging accuracy. Targeted NGS can identify genetic alterations with therapeutic implications.

[Analysis on the Prognostic and Survival Factors of Synchronous Multiple Primary Lung Cancer]

BACKGROUND

Synchronous multiple primary lung cancer (sMPLC) is a sparse disease in the past, but there has been a gradual increase in the morbidity of sMPLC recently. However, studies on large sample have never been undertaken. The purpose of this study is to investigate the diagnosis, treatment and prognosis of sMPLC through analyzing the clinical data, and provide supports for the management of sMPLC.

METHODS

According to Martini-Melamed criteria, 357 patients were diagnosed sMPLC. The pathological staging is on the basis of the 8th edition tumor-node-metastasis (TNM) staging from International Association for the Study of Lung Cancer (IASLC).

RESULTS

There were 269 patients with double primary lung cancer, 65 patients with triple primary lung cancer and 23 patients with four or more primary lung cancer. Lesions (68.55%, 571/833) were frequently in upper lobe, especially the right upper lobe. Adenocarcinoma (95.56%, 796/833) was the mainly pathological type, followed by squamous cell carcinoma (2.40%, 20/833). The acinar predominant subtype was the main part (70.81%, 313/442) of the all adenocarcinoma specimens. Most of the lesions (68.35%, 244/357) were stage Ib or low. Among the initial lesion and the following lesions ,patients who had the same pathological type (92.72%, 331/357) were more than the different (7.28%, 26/357), of which adenocarcinoma-adenocarcinoma occupied the major proportion (99.40%, 329/331). The 3-year overall survival (OS) and 5-year overall survival were respective 91.93% and 84.37%. Multivariate analysis found that smoking history (P=0.012), the diameter of the maximum lesion (P=0.027), lymph node metastasis (P=0.015) and pleural invasion (P<0.001) were the independent risk factors for prognosis.

CONCLUSIONS

Tumours in patients with sMPLC are more frequently in the right upper lobe. Adenocarcinoma was the mainly pathological type. Smoking history, the diameter of the maximum lesion, lymph node metastasis and pleural invasion were the independent risk factors for prognosis. Early diagnosis and active operation can obtain better prognosis.

Survival rate and prognostic factors of surgically resected clinically synchronous multiple primary non-small cell lung cancer and further differentiation from intrapulmonary metastasis

BACKGROUND

The diagnosis, staging, and therapeutic strategy for synchronous multiple primary non-small cell lung cancer (SMP-NSCLC) remain unclear. Distinguishing SMP-NSCLC from intrapulmonary metastasis is difficult but of great importance for selecting the surgical procedure and prognoses.

METHODS

Fifty-two patients diagnosed with SMP-NSCLC according to the modified Martini-Melamed criteria in the thoracic surgery department of the China-Japan Friendship Hospital from November 2004 to December 2015 were enrolled in this retrospective study. A total of 106 tumors were subjected to pathological examination. Close follow-up and survival analysis were performed.

RESULTS

The perioperative morbidity rate was 5.8%, with no cases of perioperative death. The overall 5-year survival rate was 40.6%, the cancer-specific 5-year survival rate was 54.5%, and the median survival time was 52 months. Older age (P=0.553), sex (P=0.600), smoking history (P=0.496), tumor distribution (P=0.461), video-assisted thoracoscopic surgery (VATS) (P=0.398), and adjuvant chemotherapy (P=0.078) did not affect survival. Preoperative percentage of forced expiratory volume in the first second (P=0.022), Charlson comorbidity index (P=0.034), surgical procedure (P=0.040), and highest pT stage (P=0.022) were independent risk factors in the multivariate analysis. Different pathological subtypes were identified in 13 of 18 cases of multiple adenocarcinomas. Different gene mutation types and correlations between tumors were identified through NGS in those with the same pathological subtype.

CONCLUSIONS

Postoperative survival rates in SMP-NSCLC were satisfactory. Non-radical resection might improve the prognosis for patients with a tolerable general condition and pulmonary function. Higher pT stage might result in poorer survival rates. Larger sample size and future study are still needed to identify the prognostic factors. Comprehensive histologic assessment and next generation sequencing (NGS) could be effective methods for screening SMP-NSCLC.

Targeted sequencing may facilitate differential diagnostics of pulmonary tumours: a case series

Background

Histopathological diagnosis is important for prognostication and choice of treatment in patients with cancer in the lung. Metastases to the lungs are common and need to be distinguished from primary lung cancer. Furthermore, cases with synchronous or metachronous primary lung cancers (although infrequent) are often handled differently than cases with lung cancer with intrapulmonary metastasis or relapse, respectively. In some cases, morphology and immunohistochemical staining is not sufficient for certain diagnosis.

Methods

The present study included six cases where molecular genetic analysis in form of pyrosequencing or targeted next-generation sequencing was of value for certain diagnosis of selected tumours in the lung.

Results

Two of the included cases were rare metastases to the lung; colorectal cancer with IHC profile consistent with primary lung cancer and malignant adenomyoepithelioma of the breast, respectively, where molecular genetic analysis was of aid for proving the relationship to the primary tumour. The other four cases were multiple lung adenocarcinomas where molecular genetic analysis was of aid to distinguish between intrapulmonary metastasis and synchronous tumour.

Conclusions

Comparison of molecular genetic profile may be an important tool for determination of relationship between tumours in some situations and should always be considered in unclear cases. Further studies on concordance and discordance of molecular genetic profiles between spatially or temporally different tumours with common origin may be helpful for improved diagnostics of pulmonary tumours.

[Surgical Treatment and Prognosis for Patients with Synchronous Multiple Primary Lung Adenocarcinomas]

背景与目的

随着高分辨率计算机断层扫描（high-resolution computed tomography, HRCT）应用的普及，多原发肺癌（multiple primary lung cancers, MPLC）的检出率逐年上升，其中腺癌是最常见的病理类型。目前国内外对MPLC的研究已相对多见，但罕有单独分析同时性多原发肺腺癌（synchronous multiple primary lung adenocarcinomas, SMPLA）的报道。本研究探讨SMPLA患者的临床病理特点及预后，旨在提高对SMPLA的认识。

方法

对2012年12月-2016年7月期间我科38例临床资料保存完整的SMPLA患者进行了回顾性分析。

结果

38例SMPLA患者中，男性12例，女性26例，中位年龄为58岁（39岁-73岁）。双原发肺腺癌29例，2个病灶以上9例。病灶位于同侧26例，双侧12例。同期手术34例（包括8例患者同期行双侧手术），分期手术4例。5例患者对每个病灶分别行基因检测，结果证实不同病灶的表皮生长因子受体（epidermal growth factor receptor, EGFR）基因突变类型不完全相同。1年和3年总生存率分别为96.6%和74.2%。肿瘤直径越大（P < 0.001）、T分期越高（P=0.003）、淋巴结转移（P=0.001）、TNM分期越高（P=0.022）以及术后放、化疗（P=0.009）提示总生存预后较差。

结论

对于多发的非小细胞肺癌，不能轻易地诊断为转移癌，应考虑多原发可能。EGFR基因检测可作为鉴别多原发肺腺癌与复发转移癌的临床参考。

Method for discriminating synchronous multiple lung cancers of the same histological type: miRNA expression analysis

With the development of imaging technology, an increasing number of synchronous multiple lung cancers (SMLCs) have been diagnosed in recent years. Patients with >1 tumor are diagnosed with either synchronous multiple primary lung cancers (SMPLCs) or other primary tumors and metastases. Clinical guidelines, histological characteristics, and molecular diagnostics have been used to discriminate SMPLCs from other multiple lung cancers. However, there is still ambiguity in the diagnosis of SMPLCs of the same histological type. We enrolled 24 patients with the same histological type of SMLCs and assessed their status using established clinical guidelines, comprehensive histological subtyping, and molecular analysis. The sum value of the differential microRNA (miRNA) expression profiles (ΔΔCt) with matched tumors was evaluated to discriminate SMPLCs of the same histological type from metastases. Twelve patients with lymph node metastases were included for comparison, and the sum value of the ΔΔCt of 5 miRNAs between primary tumors and lymph node metastases was <9. Patients definitively diagnosed with SMPLCs by integrated analysis were also classified as SMPLCs by miRNA analysis; 6 patients showed conflicting diagnoses by integrated and miRNA analysis and 14 were given the same classification. Analysis of miRNA expression profiles is considered to be a useful tool for discriminating SMPLCs from intrapulmonary metastases.

A case of primary non-small cell lung cancer with synchronous small cell lung cancer

Synchronous multiple primary lung cancer is an uncommon and difficult to distinguish from metastatic disease. The present study reported an extremely rare case of a 66-year-old male with non-small lung cell cancer in the left lobe and synchronous small cell lung cancer in the right lobe. The diagnosis of multiple primary lung cancer not only depends on biopsy pathology, but also requires molecular biology results. This is of great significance for the management and prognosis of multiple primary lung cancer. The management of patients with non-small cell lung cancer-small cell lung cancer produces certain unique challenges, which may require individualized treatment modality that may not strictly comply with standard practices in the setting of a single tumor.

Surgical treatment of synchronous multiple primary lung cancers: a retrospective analysis of 122 patients

BACKGROUND

Synchronous multiple primary lung cancers (SMPLC) become more common in clinical practice. To identify factors attributed to SMPLC treatment outcomes, we have reviewed our experiences with surgical resections of SMPLC and analyzed the treatment outcomes in this paper.

METHODS

We retrospectively analyzed clinical characteristics and treatment outcomes of patients who have been diagnosed as SMPLC and underwent surgical resection between 1990 and 2010. Based on EGFR and KRAS mutations, we identified 27 cases as SMPLC out of 50 cases, which were difficult to distinguish primary lung cancers from metastases. A total of 265 tumors from 122 patients were studied.

RESULTS

The 5-year survival rate for all patients was 40.5%. There was a significant difference in the 5-year survival between smokers and never-smokers (30.8% vs. 55.6%, P=0.011). Survival rate was also different between patients with same tumor histology and those with different tumor histology (46.9% vs. 24.8%, P=0.036). In addition, Solid nodule and pneumonectomy were associated with the worse survival (P=0.026, P=0.030). Multivariable analysis identified smoking status, stage, lymph node metastasis and pneumonectomy as significant independent predictive factors for overall survival.

CONCLUSIONS

Surgical treatment is a safe approach for patients with SMPLC; pneumonectomy should be avoided as far as possible given the poor prognosis. Mutational status of EGFR and KRAS may be advocated as a diagnostic criteria of synchronous lung cancer rather metastasis mainly in case of adenocarcinoma histology.

Role of epidermal growth factor mutational status for distinction between recurrent lung cancer and second primary lung cancer: case report

INTRODUCTION

In a patient with previous radically treated lung adenocarcinoma, the detection of a new lung cancer raises the question whether recurrence or a second primary lung cancer is involved. Current criteria for differentiating multiple lung tumors lack a biologic and molecular basis and may lead to misclassification with impact on survival.

OBJECTIVES

We report the case of a female patient with a recent diagnosis of lung adenocarcinoma and a previous lung adenocarcinoma submitted to curative surgical therapy 4 years before. As both lesions were resected, were of the same histologic subtype and presented the same immunohistochemistry profile; we decided to perform mutational analysis of the epidermal growth factor (EGFR) gene to differentiate between recurrence and second primary lung cancer.

METHODS

The EGFR gene was screened for mutations in exons 18, 19, 20 and 21 using direct sequencing of polymerase chain reaction products in DNA obtained from paraffin preserved cells from both tumors.

RESULTS

Mutational analysis of the EGFR gene, revealed different mutations in each tumor (both on exon 19) allowing the confirmation of the diagnosis of two metachronous primary lung cancers.

CONCLUSIONS

In this patient, mutational analysis of the EGFR gene was superior to histologic and immunohistochemistry characterization in differentiating between recurrent lung cancer and second primary lung cancer; allowing confirmation of the diagnosis of two metachronous primary lung cancers.

Pulmonary Metastases from NSCLC and MPLC (Multiple Primary Lung Cancers): Management and Outcome in a Single Centre Experience

BACKGROUND

This is an institutional review of surgical management of second pulmonary tumours in patients with history of Non-small Cell Lung Cancer (NSCLC) resection according to The American College of Chest Physicians' (ACCP) revision to the Martini and Melamed's criteria for the classification of multiple primary lung cancers (MPLC).

METHODS

All patients who underwent iterative pulmonary resections for pulmonary metastasis (Group A) or MPLC (Group B) between 2006 and 2012 were reviewed and their survivals compared accordingly. The main criteria of insertion in Group B were different histology and the same histology with disease-free interval ≤ 4 years; we excluded loco-regional recurrence in nodes and/or on bronchial stump.

RESULTS

Group A: Twenty patients; Disease free time (DFT) after first operation was 15.2 months (range 2-44). One, two and three years overall survival after second resection was 74%, 29%, 14% respectively. Group B: Thirty-six patients. One, two and three years overall survival was 94%, 81%, and 69% respectively. No statistical differences on outcome were found between the two groups in spite of the apparent worse survival rate for Group A (p=.197).

CONCLUSIONS

A further resection for additional nodules, whether designated as intrapulmonary metastases or second primary NSCLC, can be an appropriate curative strategy in selected patients with unimpaired respiratory function and no evidence of distant metastatic disease. The site, the extent of the second resection, the histology and even the stage are unlikely to be related to survival.