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.

Evaluation of surgical outcomes and prognostic factors of second primary lung cancer based on a systematic review and meta-analysis

BACKGROUND

Although surgery has been widely applied for SPLC therapy, there is still no uniform treatment approach. Whether SPLC and primary lung cancer have similar prognostic characteristics remains controversial. Herein, based on a systematic review and meta-analysis, we aimed to enucleate the influences of diverse surgical strategies and underlying prognostic factors on the prognosis of patients with both the first primary lung cancer and SPLC underwent surgical resection.

METHODS

A comprehensive and systematic literature search was implemented in three databases (MEDLINE, EMBASE, and Cochrane), and eligible studies were screened following inclusion and exclusion criteria. Meanwhile, we extracted the hazard ratios (HR) together with 95% confidence intervals (CI) for each prognostic factor, either directly or indirectly, from the enrolled literature.

RESULTS

Eleven studies (published between 2000 and 2022) were included in this study, including 1,131 SPLC patients. The overall survival (OS) exhibited no difference between patients with lobectomy and sublobar resection after SPLC (HR: 0.87, 95%CI: 0.62-1.21, P = 0.41). The patients after completion pneumonectomy had a poor prognosis (HR: 1.85, 95% CI: 1.34-2.55, P < 0.01). Poor prognostic factors after SPLC surgery included synchronous SPLC (HR: 3.38, 95%CI: 1.53-7.46, P < 0.01), tumor diameter > 2 cm (HR: 2.44, 95%CI: 1.73-3.44, P < 0.01), solid predominant in CT morphology (HR: 3.08, 95% CI: 1.14-8.33, P = 0.03), lymph node metastasis (HR: 2.79, 95%CI: 1.40-5.56), and smoking (HR: 2.37, 95%CI: 1.08-26.82, P < 0.01). Tumor disease-free interval (DFI), tumor histological type, and gender had no impact on the prognosis of patients received SPLC surgery.

CONCLUSIONS

Patients with SPLC, especially those with poor cardiopulmonary function reserve, should be prioritized for sublobar resection for treatment. These patients should also try to avoid completion pneumonectomy. Patients with synchronous SPLC, tumor diameter > 2 cm, solid predominant in CT morphology, lymph node metastasis, and smoking had a poor prognosis. Meanwhile, SPLC has similar prognostic characteristics with single primary lung cancer. However, the study has some limitations and more evidence is warranted to verify the findings.

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.

Distinguishing multiple primary lung cancers from intrapulmonary metastasis using CT-based radiomics

PURPOSE

To develop CT-based radiomics models that can efficiently distinguish between multiple primary lung cancers (MPLCs) and intrapulmonary metastasis (IPMs).

METHOD

This retrospective study included 127 patients with 254 lung tumors pathologically proved as MPLCs or IPMs between May 2009 and January 2020. Radiomics features of lung tumors were extracted from baseline CT scans. Particularly, we incorporated tumor-focused, refined radiomics by calculating relative radiomics differences from paired tumors of individual patients. We applied the L1-norm regularization and analysis of variance to select informative radiomics features for constructing radiomics model (RM) and refined radiomics model (RRM). The performance was assessed by the area under the receiver operating characteristic curve (AUC-ROC). The two radiomics models were compared with the clinical-CT model (CCM, including clinical and CT semantic features). We incorporated both radiomics features to construct fusion model1 (FM1). We also, build fusion model2 (FM2) by combing both radiomics, clinical and CT semantic features. The performance of the FM1 and FM2 were further compared with that of the RRM.

RESULTS

On the validation set, the RM achieved an AUC of 0.857. The RRM demonstrated improved performance (validation set AUC, 0.870) than the RM, and showed significant differences compared with the CCM (validation set AUC, 0.782). Fusion models further led prediction performance (validation set AUC, FM1:0.885; FM2:0.889). There were no significant differences among the performance of the FM1, the FM2 and the RRM.

CONCLUSIONS

The CT-based radiomics models presented good performance on the discrimination between MPLCs and IPMs, demonstrating the potential for early diagnosis and treatment guidance for MPLCs and IPMs.

Plasma metabolomics study in screening and differential diagnosis of multiple primary lung cancer

BACKGROUND

Multiple primary lung cancer (MPLC) is becoming increasingly common in clinical practice. Imaging examination is sometimes difficult to differentiate from intrapulmonary metastasis (IM) or single primary lung cancer (SPLC) before surgery. There is a lack of effective blood biomarkers as an auxiliary diagnostic method.

PARTICIPANTS AND METHODS

A total of 179 patients who were hospitalized and operated in our department from January to June 2019 were collected, and they were divided into SPLC with 136 patients, MPLC with 24 patients, and IM with 19 patients. In total, 96 healthy people without lung cancer were enrolled. Medical history, imaging, and pathology data were assembled from all participants. Plasma metabolomics analysis was performed by quadrupole time-of-flight tandem mass spectrometry, and data were analyzed using SPSS19.0/Simca 14.1/MetaboAnalyst5.0 software. Significant metabolites were selected by variable importance in projection, P value, and fold change. The area under the receiver operating characteristic curve was used to evaluate their diagnostic ability.

RESULTS

There were significant differences in plasma metabolite profiles between IM and MPLC. Seven metabolites were screened out. Two metabolites had higher levels in IM, and five metabolites had higher levels in MPLC. All had favorable discriminating capacity. Phosphatidyl ethanolamine (38:5) showed the highest sensitivity (0.95) and specificity (0.92). It was followed by l -histidine with sensitivity 0.92 and specificity 0.84. l -tyrosine can be used to identify SPLC and MPLC. The panel composed of related metabolites exhibited higher diagnostic ability. Eight principal metabolites caused remarkable differences between healthy people and MPLC, and five of them had area under the curves greater than 0.85, showing good discriminating power.

CONCLUSION

Through the study of plasma metabolomics, it was found that there were obvious differences in the metabolite profiles of MPLC, IM, SPLC, and the healthy population. Some discovered metabolites possessed excellent diagnostic competence with high sensitivity and specificity. They had the potential to act as biomarkers for the screening and differential diagnosis of MPLCs.

Reconsidering T component of cancer staging for T3/T4 non-small-cell lung cancer with additional nodule

Background

Non-small-cell lung cancer (NSCLC) with additional nodule(s) located in the same lobe or ipsilateral different lobe were designated as T3 and T4, respectively, which was merely defined by anatomical location of additional nodule(s), regardless of other prognostic factors.

Methods

A total of 4711 patients with T1-4, N0-2, M0 NSCLC undergoing complete resection were identified between 2009 and 2014, including 145 patients with additional nodule(s) in the same lobe (T3-Add) and 174 patients with additional tumor nodule(s) in ipsilateral different lobe (T4-Add). Overall survival (OS) was compared using multivariable Cox regression models and propensity score matching analysis (PSM).

Results

T3-Add patients [T3-Add versus T3, hazard ratio (HR), 0.695; 95% confidence interval (CI), 0.528-0.915; p = 0.009] and comparable OS with T2b patients through multivariable Cox analysis, and further validated by PSM. T4-Add patients carried a wide spectrum of prognosis, and the largest diameter of single tumor was screened out as the most effective indicator for distinguishing prognosis. T4-Add (⩽3 cm) patients had better OS than T4 patients [T4-Add (⩽3 cm) versus T4, HR, 0.629; 95% CI, 0.455-0.869; p = 0.005] and comparable OS with T3 patients. And T4-Add (>3 cm) patients had comparable OS with T4 patients.

Conclusion

NSCLC patients with additional nodule(s) in the same lobe and ipsilateral different lobe (maximum tumor diameter ⩽ 3 cm) should be further validated and considered restaging as T2b and T3 in the forthcoming 9th tumor, node, and metastasis staging system.

Differential Diagnostic Value of Histology in MPLC and IPM: A Systematic Review and Meta-Analysis

Background

The paramount issue regarding multiple lung cancer (MLC) is whether it represents multiple primary lung cancer (MPLC) or intrapulmonary metastasis (IPM), as this directly affects both accurate staging and subsequent clinical management. As a classic method, histology has been widely utilized in clinical practice. However, studies examining the clinical value of histology in MLC have yielded inconsistent results; thus, this remains to be evaluated. Here, we performed a meta-analysis to assess the differential diagnostic value of histology in MPLC and IPM and to provide evidence-based medicine for clinical work.

Methods

PubMed, Embase, and Web of Science databases were searched to collect relevant literature according to PRISMA, and inclusion and exclusion criteria were set up to screen and assess the literature. The data required for reconstructing a 2 × 2 contingency table were extracted directly or calculated indirectly from the included studies, and statistical analysis was carried out by using Stata 15, Meta-DiSc 1.4, and Review Manager 5.4 software.

Results

A total of 34 studies including 1,075 pairs of tumors were included in this meta-analysis. Among these studies, 11 were about the M-M standard and the pooled sensitivity and specificity were 0.78 (95% CI: 0.71–0.84) and 0.47 (95% CI: 0.38–0.55), respectively; 20 studies were about CHA and the pooled sensitivity and specificity were 0.76 (95% CI: 0.72–0.80) and 0.74 (95% CI: 0.68–0.79), respectively; and 3 studies were about the “CHA & Lepidic” criteria and the pooled sensitivity and specificity were 0.96 (95% CI: 0.85–0.99) and 0.47 (95% CI: 0.21–0.73), respectively. The combined pooled sensitivity, specificity, PLR, NLR, DOR, and the area under the SROC curve of the 34 studies were 0.80 (95% CI: 0.73–0.86), 0.64 (95% CI: 0.51–0.76), 2.25 (95% CI: 1.59–3.17), 0.31 (95% CI: 0.23–0.43), 7.22 (95% CI: 4.06–12.81), and 0.81 (95% CI: 0.77–0.84), respectively.

Conclusion

The current evidence indicated that histology had a moderate differential diagnostic value between MPLC and IPM. Among the three subgroups, the “CHA & Lepidic” criteria showed the highest sensitivity and CHA showed the highest specificity. Further research is necessary to validate these findings and to improve clinical credibility.

Systematic Review Registration

PROSPERO, identifier CRD42022298180.

The Diagnosis of Intrapulmonary Metastasis Multifocal Pulmonary Ground-Glass Nodules Based on Oncogenic Driver Mutation: Two Case Reports and Review of Literature

With the increased use of low-dose computed tomography (LDCT), the detection of multifocal pulmonary ground-glass nodules (GGNs) has increased. According to the current clinical guidelines, multifocal GGNs tend to be treated as the multiple primary early-stage lung adenocarcinoma. However, studies have indicated that parts of multiple GGNs may originate from single nodules via intrapulmonary metastasis (IPM). Such IPM indicates the advanced stages even when the multiple GGNs are present as the early characteristics in pathological assessments. However, no gold standard exists for the differential diagnosis of multiple IPM GGNs. Here, we report two multifocal pulmonary GGNs cases where panel sequencing (672 driver mutation loci) showed that patient 1 (P1) shared two rare epidermal growth factor receptor (EGFR) mutations (primary L747_T751del and primary T790M) in the left upper lobe anterior segment and left lower lobe superior segment, respectively. Patient 2 (P2) shared a low-frequency human epidermal growth factor receptor 2 (HER2) mutation (primary Tyr772_Ala775dup) in two GGNs located in the apicoposterior and superior lingular segment of the left lower lobe (LLL). Oncogenic driver mutations were concordant between primary tumors and metastasis. Thus, shared low-frequency driver mutations in multiple GGNs strongly suggested that IPM existed with a high probability in these patients. Also, tumor cell spread through air spaces (STAS) was identified in pathological sections of the left upper lobe (LUL) nodule of P1, suggesting aerogenous spread may have been an effective pathway for IPM. Our report suggests that oncogenic driver mutations have prominent diagnostic value for IPM. Also, GGN IPM may occur in one lung lobe and between in different lung lobes.

Discrimination Between Primary Lung Cancer and Lung Metastases by Genomic Profiling

Introduction

In cases of lung tumors that occur after treatment for malignancies in other organs, the tumor may represent either a primary lung cancer or a solitary pulmonary metastasis from the other tumor. Because some lung tumors are difficult to differentiate on the basis of imaging and pathologic findings, treatment selection is often difficult. In this study, we attempted to make a genomic diagnosis of primary and metastatic lung tumors by analyzing tumor samples using next-generation sequencing and evaluated the efficacy and validity of the genomic diagnosis.

Methods

A total of 24 patients with a solitary lung nodule and a history of other malignancies were enrolled in this study. Tumor cells were selected from tissue samples using laser capture microdissection. DNA was extracted from those cells and subjected to targeted deep sequencing of 53 genes.

Results

The driver mutation profiles of the primary lung tumors were discordant from those of the primary tumors in other sites, whereas the mutation profiles of pulmonary metastases and previous malignancies were concordant. In all 24 patients, we could diagnose either primary lung cancer (six patients) or lung metastases (18 patients) on the basis of whether gene mutation profiles were concordant or discordant. In 12 patients (50.0%), discrepancies were observed between the genomic and clinical or histopathologic diagnoses.

Conclusions

In patients with a solitary lung lesion and a history of cancer, tumor-specific mutations can serve as clonal markers, affording a more accurate understanding of the pathological condition and thus possibly improving both treatment selection and patient outcome.

Diagnostic and prognostic biomarkers in oligometastatic non-small cell lung cancer: a literature review

Objective

This review aims to summarize the possibilities of recently discovered molecular diagnostic techniques in lung cancer, by evaluating their impact on diagnosis, monitoring, and prognosis in oligometastatic disease.

Background

Oligometastatic non-small cell lung cancer (OM-NSCLC) is currently defined based on morphological rather than biological features. Major advances in the detection of molecular biomarkers in cell-free tumoral DNA and the models of oncogene addiction make as feasible an early diagnosis and guide the therapeutic decision-making progress to improve the prognosis.

Methods

This narrative review EXAMINES current approaches of diagnosis, monitoring, and prognosis of OM-NSCLC and describes the fast-evolving therapeutic scenario of this disease. We provide an overview of the powerful capability of liquid biopsy techniques applied to blood and fluid and we focus on the technological advancement of circulant biomolecular factors in OM NSCLC pathology, starting from apparently simpler models such as oncogene addicted tumors to evaluate themselves in the light of treatment with immune-checkpoint inhibitors.

Conclusions

A better understanding of spatial and temporal evolution of oligometastatic diseases would contribute to a more accurate diagnosis and tailored treatment. Data from prospective clinical trials in the early stage of disease, coupled with knowledge of genetic characteristics of lung tumors, are warranted. These efforts would lead to improving the possibility to eradicate the residual disease in these low burden tumoral settings, thus enhancing the definitive cure perspectives.

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.

Distinguishing multiple lung primaries from intra-pulmonary metastases and treatment implications

INTRODUCTION

The distinction between multiple primary lung cancers and intra-pulmonary metastases has been extensively investigated because of its important clinical and therapeutic implications.

AREAS COVERED

Rapidly improving imaging technology and genomic analysis has led to a finer discrimination between multiple primary lung tumors and pulmonary metastases. However, over the past few decades, standardized criteria for the identification of multiple lung tumors have been lacking. Therefore, in 2017 a multidisciplinary international committee composed of the Union for International Cancer Control (UICC), American Joint Committee on Cancer (AJCC) and International Association for the Study of Lung Cancer (IASLC) addressed this problem when drawing up the 8th edition of TMN stage classification, that now represents a specific consensus on this topic. The most advanced diagnostic strategies associated with screening allow for the detection of early stage synchronous lung cancers.

EXPERT OPINION

Although diagnostic confirmation relies on pathologic and clinical examination, new molecular analyses help in the discrimination between primary and secondary tumors. The treatment of multiple primary lung tumors remains, whenever possible, a local treatment based on surgical resection, providing the absence of distant or local (lymph node) metastases.

A comprehensive algorithm to distinguish between MPLC and IPM in multiple lung tumors patients

Background

Diagnosis of multiple lung nodules has become convenient and frequent due to the improvement of computed tomography (CT) scans. However, to distinguish intrapulmonary metastasis (IPM) from multiple primary lung cancer (MPLC) remains challenging. Herein, for the accurate optimization of therapeutic options, we propose a comprehensive algorithm for multiple lung carcinomas based on a multidisciplinary approach, and investigate the prognosis of patients who underwent surgical resection.

Methods

Patients with multiple lung carcinomas who were treated at West China Hospital of Sichuan University from April, 2009 to December, 2017, were retrospectively identified. A comprehensive algorithm combining histologic assessment, molecular analysis, and imaging information was used to classify nodules as IPM or MPLC. The Kaplan-Meier method was used to estimate survival rates, and the relevant factors were evaluated using the log-rank test or Cox proportional hazards model.

Results

The study included 576 patients with 1,295 lung tumors in total. Significant differences were observed between the clinical features of 171 patients with IPM and 405 patients with MPLC. The final classification consistency was 0.65 and 0.72 compared with the criteria of Martini and Melamed (MM) and the American College of Chest Physicians (ACCP), respectively. Patients with independent primary tumors had better overall survival (OS) than patients with intra-pulmonary metastasis (HR =3.99, 95% CI: 2.86–5.57; P<0.001). Nodal involvement and radiotherapy were independent prognostic factors.

Conclusions

The comprehensive algorithm was a relevant tool for classifying multifocal lung tumors as MPLC or IPM, and could help doctors with precise decision-making in routine clinical practice. Patients with multiple lesions without lymph node metastasis or without radiotherapy tended to have a better prognosis.

Long-term instillation to four natural representative chrysotile of China induce the inactivation of P53 and P16 and the activation of C-JUN and C-FOS in the lung tissues of Wistar rats

Chrysotile is the only type of asbestos still widely exploited, and all kinds of asbestos including chrysotile was classified as a group I carcinogen by the IARC. There is a wealth of evidence that chrysotile can cause a range of cancers, including cancer of the lung, larynx, ovary, and mesothelioma. As the second largest chrysotile producer, China is at great risk of occupational exposure. Moreover, our previous experiment and some other studies have shown that the toxicity of mineral fibre from various mining areas may be different. To explore the oncogenic potential of chrysotile from different mining areas of China, Wistar rats were administered 0.5 mL chrysotile asbestos suspension of 2.0 mg/mL (from Akesai, Gansu; Mangnai, Qinghai; XinKang, Sichuan; and Shannan, Shaanxi) dissolved in saline by intratracheal instillation once-monthly and were sacrificed at 1 mo, 6 mo, and 12 mo. Our results found that chrysotile caused lung inflammation and lung tissue damage. Moreover, prolonged exposure of chrysotile can induce inactivation of the tumor suppressor gene P53 and P16 and activation of the protooncogene C-JUN and C-FOS both in the messenger RNA and protein level. In addition, chrysotile from Shannan and XinKang has a stronger effect which may link to cancer than that from Akesai and Mangnai.

Clinical outcomes of stereotactic body radiotherapy for de novo pulmonary tumors in patients with completely resected early stage non-small cell lung cancer

Purpose

Following surgery for early stage non-small-cell lung cancer (NSCLC), de novo pulmonary tumors are common. This study aimed to assess the efficacy, patterns of failure, and toxicity of stereotactic body radiotherapy (SBRT) in the treatment of de novo pulmonary tumors following curative resection of early stage NSCLC.

Patients and methods

We reviewed the medical data of patients who had received definitive intent SBRT for small lung cancer at Zhongshan Hospital, Fudan University, between June 2011 and December 2017. Patients who had experienced complete resection for prior early stage NSCLC before SBRT were identified for further analysis. Incidences of locoregional recurrence (LR) and distant metastasis (DM) were evaluated using the alternative cumulative incidence competing risk method. The probability of survival was estimated using the Kaplan–Meier method.

Results

A total of 33 patients with 36 lesions were eligible and included in this study. The median follow-up time was 32 months. Estimated incidences of LR and DM were 37.62% and 15.92%, respectively, at 1 year and 48.02% and 21.23%, respectively, at 2 years. The progression-free survival and overall survival of all patients were 62.40% and 90.30%, respectively, at 1 year and 52.00% and 69.90%, respectively, at 2 years. In all, 26 patients experienced grade 1 SBRT-related toxicity, 11 patients experienced grade 2 SBRT-related toxicity, and three patients experienced grade 3 toxicity. There were no grade 4/5 toxicities or SBRT-related deaths during the follow-up period.

Conclusion

SBRT appears to be a safe and potentially effective alternative therapeutic option for de novo pulmonary tumors following early stage NSCLC radical resection, despite impaired pulmonary reserve.

[Experience and Progress Processing Policy of Simultaneous Multiple Primary Lung Cancer]

BACKGROUND

Simultaneity multiple primary lung cancer always is a rare disease, but in recent years due to the progress of the diagnosis and treatment means detection rate increased. This study summarized the clinical data of 31 cases of synchronous multiple primary lung cancer (sMPLC) analysis, further to explore the diagnosis, treatment and prognosis of MPLC.

METHODS

Sum up the clinical data of 31 cases of simultaneous multiple primary lung cancer, the diagnostic method, surgical methods, pathology, were retrospectively analyzed.

RESULTS

All the patients are thoracoscope surgery, no deaths. Thin high resolution computed tomography (CT) in preoperative found multiple lung nodules. Lesions located in the same side of the same period surgical treatment, the operation method is given priority to with under the thoracoscope lung + the lobectomy; Lesions located in bilateral, all staged operation, the time interval for 3 months-4 months.

CONCLUSIONS

Thin layer distinguish CT preoperative diagnosis is the best way to simultaneous multiple primary lung cancer. Multiple primary lung cancer incidence of ipsilateral lung at the same time higher than that of bilateral lung (23:8), type, around 94%, the most common histology to adenocarcinoma, 80.6% (25/31). Primary lesions under thoracoscope lobectomy plus the lobectomy of secondary lesions is the most commonly used.

Lung injury and expression of p53 and p16 in Wistar rats induced by respirable chrysotile fiber dust from four primary areas of China

Chrysotile products were widely used in daily life, and a large amount of respirable dust was produced in the process of production and application. At present, there was seldom research on the safety of chrysotile fiber dust, and whether its long-term inhalation can lead to lung cancer was unknown. In order to determine whether respirable chrysotile fiber dust of China caused lung cancer, four major chrysotile-producing mine areas in China were selected for this study. Chrysotile fibers were prepared into respirable dust. Particle size was measured by laser particle analysis, morphology was observed by scanning electron microscope, chrysotile fiber phase was analyzed by X-ray diffraction, trace chemical elements were identified by X-ray fluorescence, and the structure and the active groups of the dust were determined after grinding by Fourier transform infrared spectroscopy. Male Wistar rats were exposed to non-exposed intratracheal instillation with different concentrations of chrysotile fiber dust. The rats were weighed after 1, 3, and 6 months, then the lung tissues were separated, the lung morphology was observed, and the pulmonary index was calculated. Pathological changes in lung tissues were observed by optical microscope after the HE staining of tissues, and the gene expression of p53 and p16 was determined by reverse transcription polymerase chain reaction. First, the results showed that the particle sizes of the four fibers were less than 10 μm. Four primary areas of chrysotile had similar fibrous structure, arranged in fascicles, or mixed with thin chunks of material. Second, the elementary composition of the four fibers was mainly chrysotile, and the structure and the active groups of the grinding dust were not damaged. Third, the weights of the treated rats were obviously lower, and the lung weights and the pulmonary index increased significantly (P < 0.05). Fourth, the treated Wistar rat lung tissues revealed different degrees of congestion, edema, inflammatory cell infiltration, and mild fibrosis. Fifth, the p53 and p16 genes decreased in the Mangnai group after 1 month of exposure, and the other groups increased. The expression of p53 and p16 in each group decreased significantly after 6 months (P < 0.05). In conclusion, the respirable chrysotile fiber dust from the four primary areas of China had the risk of causing lung injury, and these changes may be related to the physical and chemical characteristics of chrysotile from different production areas.

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.

Use of Oncogenic Driver Mutations in Staging of Multiple Primary Lung Carcinomas: A Single-Center Experience

OBJECTIVE

The staging of multiple pulmonary adenocarcinomas requires the distinction of intrapulmonary metastasis (IPM) from multiple primary lung cancers (MPLCs). This can be challenging in some patients, and the addition of data from oncogenic driver mutations in these tumors may be helpful in this determination.

METHODS

As a proof of principle, molecular driver results from primary tumors and their metastases in 45 patients were compared (cohort 1). Then, 69 patients with a total of 154 synchronous or metachronous lung carcinomas were identified, and the pathologic findings were compared with oncogenic driver mutation. Each patient was assigned a highest potential T or M category on the basis of clinical, histopathologic, and molecular findings (cohort 2).

RESULTS

The concordance rate of EGFR, KRAS, BRAF, and ALK receptor tyrosine kinase gene (ALK) mutations was 96% in cohort 1. In cohort 2, 36% of multiple same-lobe nodules were MPLCs, 40% were IPM, and 24% were noninformative by molecular findings. Of nodules with multiple lobe involvement, 81.5% were MPLCs and 7.4% were IPM, with 11% noninformative. Of metachronous tumors, 52.9% were MPLCs. Overall survival was 100% at 2 years, 95% at 3 years, and 80% at 4 years in patients with available follow-up.

CONCLUSIONS

Oncogenic driver mutations are concordant between primary tumors and metastasis. The largest proportion of MPLCs was seen in tumors of multiple lobes, but with a substantial proportion of MPLCs among single-lobe nodules and with metachronous tumors. Overall survival was higher than expected for the respective highest T or M category, which is in support of the high frequency of MPLC.

[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。

[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.

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.

[Advances in Diagnosis and Treatment of Multiple Primary Lung Cancer]

多原发性肺癌的发病率和检出率逐年升高。目前临床上诊断多原发性肺癌(multiple primary lung cancer, MPLC)主要参照Martini-Melamed标准和美国胸科医师协会(American College of Chest Physicians, ACCP)标准, 综合考虑临床表现、影像学特征、组织学类型和分子遗传学特征。组织学类型不同的MPLC诊断相对容易, 而组织学类型相同的MPLC诊断仍相当困难。DNA倍体分析、基因突变检测、微卫星多态性分析等分子生物学技术为MPLC的正确诊断提供了新手段, 可评估各病灶的克隆性关系, 帮助鉴别MPLC与转移。MPLC的首选治疗方案为根治性手术, 术式应考虑患者肺功能储备等因素, 选择肺叶切除、肺段切除或楔形切除; 对于不能根治性切除的病灶, 可综合化疗、放疗、立体定向放疗(stereotactic ablative radiotherapy, SABR)、射频消融(radiofrequency ablation, RFA)、分子靶向治疗等。

"Different trend" in multiple primary lung cancer and intrapulmonary metastasis

Background

The distinguishing of intrapulmonary metastatic tumors from multiple primary lung cancers is difficult but of great importance for the therapeutic management and prognosis of these patients.

Methods

We used genomic DNA analyzed by six microsatellites (D7S1824, D15S822, D2S1363, D10S1239, D6S1056, and D22S689) with PCR to identify discordant allelic variation from 12 patients. There are five patients with multiple primary lung cancers and seven patients who were diagnosed with intrapulmonary metastases from 850 patients with primary lung cancer in our hospital. The experiments were approved by the West China Hospital Ethics committee (No. 2013 (33)) and all patients agreed to participate in the study and signed an informed consent form.

Results

In the group of metachronous lung tumor, three of five patients have different histological types and one of five patients have the same histological type which showed “contradictory trend”. The other one showed “unique trend”. In the second group (intrapulmonary metastasis lung tumor), one patient showed “contradictory trend” and the others showed “unique trend”.

Conclusions

“Different trends” are useful in discrimination of intrapulmonary metastasis lung cancer and multiple primary lung cancer even diagnosed with the histopathological evaluation.

Prognosis of synchronous and metachronous multiple primary lung cancers: systematic review and meta-analysis

BACKGROUND

With the development of imaging technology, an increasing number of multiple primary lung cancers (MPLC) are diagnosed in recent years. However, there is still ambiguity in the stage classification rules for patients with MPLC. Our purpose was to access the prognosis of synchronous and metachronous MPLC.

METHODS

A systematic literature search was performed on four databases (EBSCO, Pubmed, OVID and Springer) to obtain relevant articles. We used published hazard ratios (HRs) of overall survival (OS) if available or estimates from the published survival data.

RESULTS

There were 1796 patients with MPLC in 22 relevant studies, who were eligible for analysis. We found that the OS of patients with synchronous MPLC was inferior to the one of metachronous MPLC patients when starting from the diagnosis of the first metachronous tumor (HR 3.36, 95% CI 2.39-4.74; p<0.001). However, there was no difference when starting from the diagnosis of the second metachronous tumor (HR 1.19, 95% CI 0.86-1.66; p=0.29). From further analysis we found the OS of patients with MPLC was superior to that of patients with intrapulmonary metastasis (HR 2.66, 95% CI 1.30-5.44; p=0.007). Besides, we found no difference in OS between synchronous (HR 1.39, 95% CI 0.98-1.96; p=0.06) and metachronous (HR 1.05, 95% CI 0.75-1.47; p=0.77) patients, in spite of the histology. In terms of unilateral and bilateral MPLC patients, the OS had no difference either (HR 1.30, 95% CI 1.00-1.69; p=0.05).

CONCLUSION

We found that MPLC had better OS than the lung cancer patients with intrapulmonary metastasis. And despite the tumor-free interval, the OS for metachronous MPLC was as good as that for synchronous MPLC. Furthermore, there was no difference of OS in different subgroups, including histology and position.

Diagnosis of multiple primary lung cancer: A systematic review

A substantial percentage (8%) of all newly diagnosed cancer cases are in patients with previous tumours, with a similar trend in lung cancer. Cases of multiple primary lung cancer (MPLC) are increasing worldwide, due to improved diagnostic and surveillance mechanisms and the ageing population. Diagnosis of MPLC is complicated by difficulties in distinguishing it from lung cancer metastasis. Clinicopathological assessment, diagnosis and management have evolved, but remain severely limited by the lack of robust and dependable molecular markers for the differential diagnosis of metastasis and MPLC. This systematic review evaluates diagnostic criteria for MPLC, and the subsequent management and success rates. The incorporation of molecular biology techniques into the diagnostic process for MPLC is also discussed.

Identification of intravascular tumor microenvironment features predicting the recurrence of pathological stage I lung adenocarcinoma

Histological vascular invasion (VI) by tumors is reportedly a risk factor influencing recurrence or survival after surgical treatment; however, few studies have evaluated which VI features affect recurrence or survival. The objective of this study was to evaluate how VI features affect recurrence in lung adenocarcinoma patients. We selected 106 patients with pathological stage I lung adenocarcinoma who showed VI and examined the properties of intravascular tumors associated with recurrence. First we investigated the relationship between the frequency of VI in a histological cross-section and the incidence of recurrence; however, a significant impact was not observed. Microscopic examination revealed the intravascular tumors were composed of not only cancer cells but also non-cancerous cells. To examine whether the characteristics of intravascular cancer cells and/or non-cancerous cells have prognostic value, we examined the expression levels of epithelial-mesenchymal transition-related markers in cancer cells and the numbers of infiltrating non-cancerous cells, including macrophages, endothelial cells, and fibroblasts. High levels of E-cadherin expression in the intravascular cancer cells were significant predictors of recurrence (P = 0.004), whereas the expressions of CD44, CD44 variant 6, and vimentin were not. Large numbers of intravascular CD204(+) macrophages (P = 0.016), CD34(+) microvessels (P = 0.007), and α-smooth muscle actin (+) fibroblasts (P = 0.033) were also significant predictors of recurrence. Our results indicated VI with abundant stromal cell infiltrates might be a predictor of recurrence and suggested the tumor microenvironment created by cancer cells and stromal cells within the blood vessel may play an important role during the metastatic process.

Morphophenotypic characteristics of intralymphatic cancer and stromal cells susceptible to lymphogenic metastasis

The intravessel microenvironment has significant effects on cancer metastasis. The aim of the present study was to determine how the morphologic and immunophenotypic features of cancer cells and infiltrating stromal cells within the permeated lymphatic vessels are associated with lymphogenic metastasis. A total of 137 primary lung adenocarcinoma patients with extratumoral lymphatic permeations were examined. Morphologically, the floating cancer nests within the permeated lymphatic vessels were divided into two types: Type A, consisting of a single large cancer nest; and Type B, consisting of multiple small cancer nests. We compared the clinicopathologic characteristics and the immunophenotypes of the cancer cells and infiltrating stromal cells between the Type A and Type B nests. Eleven of 54 Type A patients (20%) had intrapulmonary metastases, compared with 36 of 83 Type B patients (43%; P = 0.006). Immunohistochemically, Type B cancer cells expressed significantly higher levels of CD44 than Type A cancer cells (mean scoresAUTHOR: Scores - what is this score? Is it the number of cells expressing CD44 or the concentration of CD44 or some other type of scoring system? 43.0 vs 20.5, respectively) and E-cadherin (60.5 vs 31.5, respectively), but lower levels of Geminin (11.9% vs 20.3%, respectively) and cleaved caspase 3 (2.4% vs 7.8%AUTHOR: 11.9% vs 20.3%, respectively) and cleaved caspase 3 (2.4% vs 7.8%, - what do the percentages here refer to? The number of cells expressing geminin and caspase 3? The levels of these factors? Please clarify., respectively). Moreover, a significantly larger number of CD204-positive macrophages were present within the cancer-permeated lymphatic vessels in Type B patients than in Type A patients (mean number 9.5 vs 4.6, respectively). The present study reveals that intralymphatic cancer cell and stromal cell phenotypes are susceptible to lymphogenic metastasis, suggesting that lymphogenic metastasis may be affected by the intralymphatic microenvironment they create.

Targeting p27Kip1 protein: its relevance in the therapy of human cancer

INTRODUCTION

Cell division cycle progression is achieved by a sequential and stringently concerted activation of a family of serine-threonine kinases, namely the cyclin-dependent kinases (CDKs). p27(Kip1) is a pivotal CDK inhibitor and a tight modulator of CDK-dependent phenotypes. Thus, p27(Kip1) plays a fundamental role in key cellular processes such as proliferation, differentiation, apoptosis, substrate adhesion and motility. Intriguingly, when p27(Kip1) is localized in the nucleus, it acts as an antiproliferative protein, while, in the cytosol, p27(Kip1) promotes cytoskeleton remodeling and might positively influence metastatization. Downregulation of p27(Kip1) nuclear level or its cytosolic mislocalization are consistently correlated with poor prognosis of numerous types of human epithelial and non-epithelial cancers.

AREAS COVERED

This review illustrates the basic structural features of p27(Kip1) protein, its metabolism and alterations in human malignancies, along with describing anticancer strategies based on targeting p27(Kip1).

EXPERT OPINION

Given the role of p27(Kip1) in the control of cell proliferation and its decreased level observed in malignancies with poor outcome, drugs able to handle the protein levels and localization might represent an important goal for novel specific and effective anticancer strategies. Although no convincing proofs have been reported, putative negative consequences of p27(Kip1) targeting might be also conceivable.