A combination of molecular markers accurately detects lymph node metastasis in non-small cell lung cancer patients

Liquid Biopsy in Lung Cancer: Nano-Flow Cytometry Detection of Non-Small Cell Lung Cancer in Blood

Non-small cell lung cancer (NSCLC) remains a leading cause of global mortality, with current screening and diagnostic methods often lacking in sensitivity and specificity. In our endeavor to develop precise, objective, and easily accessible diagnostic biomarkers for NSCLC, this study aimed to leverage rapidly evolving liquid biopsy techniques in the field of pathology to differentiate NSCLC patients from healthy controls by isolating peripheral blood samples and enriching extracellular vesicles (EVs) containing lung-derived proteins (TTF-1 and SFTPB), along with the cancer-associated protein CD151+ EVs. Additionally, for practical applications, we established a nano-flow cytometry assay to detect plasma EVs readily. NSCLC patients demonstrated significantly reduced counts of TTF-1+ EVs and CD151+ EVs in plasma compared to healthy controls (P<0.0001), while SFTPB+ EVs showed no significant difference (P>0.05). Integrated analysis of TTF-1+, CD151+ and SFTPB+ EVs yielded area under the curve (AUC) values of 0.913 and 0.854 in the discovery and validation cohorts, respectively. Thus, while further validation is essential, the newly developed technologies are of great significance for the robust detection of NSCLC biomarkers.

Lymph node metastasis in early invasive lung adenocarcinoma: Prediction model establishment and validation based on genomic profiling and clinicopathologic characteristics

BACKGROUND

The presence of lymph node (LN) metastasis directly affects the treatment strategy for lung adenocarcinoma (LUAD). Next-generation sequencing (NGS) has been widely used in patients with advanced LUAD to identify targeted genes, while early detection of pathologic LN metastasis using NGS has not been assessed.

METHODS

Clinicopathologic features and molecular characteristics of 224 patients from Ruijin Hospital were analyzed to detect factors associated with LN metastases. Another 140 patients from Huashan Hospital were set as a test cohort.

RESULTS

Twenty-four out of 224 patients were found to have lymph node metastases (10.7%). Pathologic LN-positive tumors showed higher mutant allele tumor heterogeneity (p < 0.05), higher tumor mutation burden (p < 0.001), as well as more frequent KEAP1 (p = 0.001), STK11 (p = 0.004), KRAS (p = 0.007), CTNNB1 (p = 0.017), TP53, and ARID2 mutations (both p = 0.02); whereas low frequency of EGFR mutation (p = 0.005). A predictive nomogram involving male sex, solid tumor morphology, higher T stage, EGFR wild-type, and TP53, STK11, CDKN2A, KEAP1, ARID2, KRAS, SDHA, SPEN, CTNNB1, DICER1 mutations showed outstanding efficiency in both the training cohort (AUC = 0.819) and the test cohort (AUC = 0.780).

CONCLUSION

This study suggests that the integration of genomic profiling and clinical features identifies early-invasive LUAD patients at higher risk of LN metastasis. Improved identification of LN metastasis is beneficial for the optimization of the patient's therapy decisions.

Downregulation of pro-surfactant protein B contributes to the recurrence of early-stage non-small cell lung cancer by activating PGK1-mediated Akt signaling

Recurrence is one of the main causes of treatment failure in early-stage non-small cell lung cancer (NSCLC). However, there are no predictors of the recurrence of early-stage NSCLC, and the molecular mechanism of its recurrence is not clear. In this study, we used clinical sample analysis to demonstrate that low levels of expression of precursor surfactant protein B (pro-SFTPB) in primary NSCLC tissue compared to their adjacent tissues are closely correlated with recurrence and poor prognosis in early-stage NSCLC patients. In vitro and in vivo experiments showed that downregulation of pro-SFTPB expression activates the Akt pathway by upregulating PGK1, which promotes metastasis and tumorigenicity in NSCLC cells. We then demonstrated that pro-SFTPB suppresses the formation of the ADRM1/hRpn2/UCH37 complex by binding to ADRM1, which inhibits PGK1 deubiquitination, thus accelerating ubiquitin-mediated PGK1 degradation. In summary, our findings indicate that low expression of pro-SFTPB in primary NSCLC compared to their adjacent tissue has potential as a predictor of recurrence and poor prognosis in early-stage NSCLC. Mechanistically, downregulation of pro-SFTPB attenuates inhibition of ADRM1-deubiquitinated PGK1, resulting in elevated levels of PGK1 protein; this activates the Akt pathway, ultimately leading to the progression of early-stage NSCLC.

Combination of CEACAM5, EpCAM and CK19 gene expressions in mediastinal lymph node micrometastasis is a prognostic factor for non-small cell lung cancer

BACKGROUND

Lung cancer is known as the most common and highly metastatic form of cancer worldwide. Tumour node metastasis (TNM) staging is the gold standard classification system for the decision-making process for appropriate treatment. Particularly N status has the most important prognostic value in the absence of distant metastasis. Traditional diagnostic methods are capable of detecting metastasis; however, they may fail to detect micrometastasis, which plays a role in disease recurrence and patients' long-term survival. Occult micrometastasis can change the tumour's TNM staging and, consequently, the patient's treatment regimen.

METHODS

The median number of three lymph node tissues were collected from 30 patients who underwent surgery for non-small cell lung cancer. Lymph node tissues were collected from different lymph node stations according to the location of the patient's tumour. CK19, EpCAM and CEACAM5 gene expressions were analysed in tissues using quantitative real-time polymerase chain reaction to detect micrometastasis in distant lymph nodes.

RESULTS

Triple positivity was seen in 26 out of 30 patients which 19 patients were upstaged from N0 to N2. While survival was not significantly affected between upstaged and non-upstaged patients, patients upstaged with multiple-station N2 had a significantly higher recurrence and lower survival compared to single-station N2.

CONCLUSION

A combination of CK19, EpCAM and CEACAM5 gene expressions in lymph nodes can be used to identify micrometastasis which postoperatively may be used as a tool to predict patients' recurrence and survival.

Molecular Features in Lymphatic Metastases Reflect the Metastasis Mechanism of Lymph Nodes With Non-Small-Cell Lung Cancers

Lymphatic metastasis influences clinical treatment and prognosis of patients with non-small-cell lung cancer (NSCLC). There is an urgency to understand the molecular features and mechanisms of lymph node metastasis. We analyzed the molecular features on pairs of the primary tumor and lymphatic metastasis tissue samples from 15 NSCLC patients using targeted next-generation sequencing. The potential metastasis-related genes were screened from our cohort based on cancer cell fraction. After filtering with gene functions, candidate metastasis-related events were validated in the MSK cohort with Fisher's exact test. The molecular signature and tumor mutational burden were similar in paired samples, and the average mutational concordance was 42.0% ± 28.9%. Its metastatic mechanism is potentially a linear progression based on the metastatic seeding theory. Furthermore, mutated ataxia telangiectasia mutated and Rad3-related (ATR) and tet methylcytosine dioxygenase 2 (TET2) genes were significantly enriched in lymphatic metastases (p ≤ 0.05). Alterations in these two genes could be considered metastasis-related driving events. Mutated ATR and TET2 might play an active role in the metastasis of lymph nodes with NSCLC. More case enrollment and long-term follow-up will further verify the clinical significance of these two genes.

Differences in the Relative Abundance of ProBDNF and Mature BDNF in A549 and H1299 Human Lung Cancer Cell Media

Brain-derived neurotrophic factor (BDNF), a member of the neurotrophin family, has been linked to several human malignancies and shown to promote tumorigenesis. The purpose of this study was to explore the relative abundance of pro-brain-derived neurotrophic factor (proBDNF) and mature BDNF (mBDNF) in A549 (p53 wild-type) and H1299 (p53-null) lung cancer cell media. Higher levels of proBDNF were detected in the media of A549 cells than in H1299 cell media. Using inhibitors, we found that the levels of proBDNF and mBDNF in the media are likely regulated by PI3K, AKT, and NFκB. However, the largest change in these levels resulted from MMP2/9 inhibition. Blocking p53 function in A549 cells resulted in increased mBDNF and decreased proBDNF, suggesting a role for p53 in regulating these levels. The ratio of proBDNF/mBDNF was not affected by MMP2 knockdown but increased in the media of both cell lines upon knockdown of MMP9. Downregulation of either MMP2 or MMP9 by siRNA showed that MMP9 siRNA treatment of either A549 or H1299 cells resulted in decreased cell viability and increased apoptosis, an effect diminished upon the same treatment with proBDNF immunodepleted media, suggesting that MMP9 regulates the cytotoxic effects induced by proBDNF in lung cancer cells.

Molecular Nodal Restaging Based on CEACAM5, FGFR2b and PTPN11 Expression Adds No Relevant Clinical Information in Resected Non-Small Cell Lung Cancer

BACKGROUND

The relapse rate in non-small cell lung cancer (NSCLC) is high, even in localized disease, suggesting that the current approach to pathological staging is insufficiently sensitive to detect occult micrometastases present in resected lymph nodes. Therefore, we aimed to determine the prognostic value of the expression of embryonic molecular markers in histologically-negative lymph nodes of completely-resected NSCLC.

METHODS

76 completely-resected NSCLC patients were included: 60 pN0 and 16 pN1. Primary tumors and 347 lymph node were studied. CEACAM5, FGFR2b, and PTPN11 expression levels were evaluated through mRNA analysis using real-time RT-qPCR assay. Statistical analyses included the Kruskal-Wallis test, Kaplan Meier curves, and log-rank tests.

RESULTS

CEACAM5 expression levels were scored as high in of 90 lymph nodes (26%). The molecular-positive lymph nodes lead to the restaging of 37 (62%) pN0 patients as molecular N1 or N2 and 5 (31%) pN1 cases were reclassified as molecular-positive N2. Surprisingly, molecular-positive patients associated with a better OS (overall survival, p = 0,04). FGFR2b overexpression was observed in 41 (12%) lymph nodes leading to the restaging of 17 patients (22%). Again a trend was observed toward a better DFS (disease-free survival) in the restaged patients (p = 0,09). Accordingly, high expression levels of CEACAM5 or FGFR2b in the primary were related to better DFS (p = 0,06; p < 0,02, respectively).

CONCLUSION

Molecular nodal restaging based on expression levels of CEACAM5 and/or FGFR2b, does not add relevant clinical information to pathological staging of NSCLC likely related to the better prognosis of their overexpression in primary tumors.

Intraoperative diagnosis of lymph node metastasis during segmentectomy for non-small cell lung cancer by rapid immunohistochemistry using noncontact alternating current electric field mixing

Background

Although lobectomy is considered the standard surgery for any non‐small cell lung cancer (NSCLC), recent evidence indicates that for early NSCLCs segmentectomy may be equally effective. For segmentectomy to be oncologically safe, however, adequate intraoperative lymph node staging is essential. The aim of this study was to compare the results of a new rapid‐IHC system to the HE analysis for intraoperative nodal diagnosis in lung cancer patients considered for segmentectomy.

Methods

This retrospective study analyzed the pathological reports from NSCLC resections over a six‐year period between 2014 and 2020. Using a new device for rapid‐IHC, we applied a high‐voltage, low‐frequency alternating current (AC) field, which mixes the antipancytokeratin antibody as the voltage is switched on/off. Rapid‐IHC can provide a nodal diagnosis within 20 minutes.

Results

Frozen sections from 106 resected lymph nodes from 70 patients were intraoperatively evaluated for metastasis. Of those, five nodes were deemed positive based on both HE staining and rapid‐IHC. In addition, rapid‐IHC alone detected isolated tumor cells in one hilar lymph node. Three cStage IA patients with nodal metastasis detected with HE staining and rapid‐IHC received complete lobectomies. Five‐year relapse‐free survival and overall survival among patients receiving segmentectomy with rapid‐IHC were 88.77% and 88.79%, respectively.

Conclusions

Rapid‐IHC driven by AC mixing is simple, highly accurate, and preserves nodal tissue for subsequent tests. This system can be used effectively for intraoperative nodal diagnosis.

Rapid immunohistochemistry based on alternating‐current field mixing (completed within 20 minutes) is simple and highly accurate. This system will assist clinicians when making intraoperative diagnoses of lymph node metastasis and deciding upon the appropriate surgical procedure in segmentectomy for lung cancer.

Key points

Significant findings of the study

Rapid immunohistochemistry driven by alternating‐current field mixing (completed within 20 minutes intraoperatively) is simple, highly accurate, and preserves lymph node tissue for subsequent pathological examination, including molecular assessments.

What this study adds

Segmentectomy for lung cancer is oncologically safe, but only when there is adequate intraoperative node staging. Rapid immunohistochemistry will assist clinicians when making intraoperative nodal diagnoses.

[Research Progress of Lymph Node Micrometastasis in Non-small Cell Lung Cancer]

The incidence and mortality of lung cancer rank top in China. One important factor is the occurrence of metastasis. With the development of science technology, the effect of surgical treatment on lung cancer is improved. Moreover, the use of targeted therapy has achieved a new height for the treatment of lung cancer. However, the recurrence rate remains high even the tumor was completely resected at early stage. The occurrence of lymph node micrometastasis is considered as one of the plausible explanations. The difficulty indetecting micrometastasis has been greatly reduced. Although studies dig deeper into the lymph node micrometastasis, there are still some controversies including the selection of surgical procedures, the pathological staging and prognosis about patients with lymph node micrometastasis. This review manages to generalize the latest research progress of lymph node micrometastasis.
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The diagnostic value of one step nucleic acid amplification (OSNA) in differentiating lymph node metastasis of tumors: A systematic review and meta-analysis

BACKGROUND

The aim of this study was clarify the diagnostic accuracy of one step nucleic acid amplification (OSNA) for differentiating metastatic lymph nodes from non-metastatic ones in patients with tumors (not including breast cancer).

METHODS

A systematic literature search for original diagnostic studies was performed in PubMed. Findings were pooled by using combined effect models and hierarchic summary receiver operating characteristic curve models. Meta-regression analysis and threshold effect evaluating were performed to explore the sources of heterogeneity affected classification accuracy.

RESULTS

19 studies (803 positive and 4594 negative lymph nodes) were analyzed, including 4 different tumor types (head and neck cancers, gastrointestinal cancers, lung cancer and gynecological malignancies). In the studies of head and neck cancers the pooled sensitivity, specificity and area under the curve (AUC) of the OSNA method were 0.85(0.79-0.89), 0.96(0.92-0.98) and 0.91 (0.88-0.93), respectively. Similarly, the corresponding values in the studies of gastrointestinal cancers were 0.90(0.85-0.94), 0.96(0.94-0.98) and 0.97 (0.96-0.99), respectively. Because of limited number of studies, the other two tumor types were inestimable in the subsequent meta-analyses.

CONCLUSIONS

Pooled data suggest that the OSNA assay has a high diagnostic accuracy for the detection of lymph node metastases. For wide spread implementation, additional studies on other different types of tumors are warranted.

The novel one-step nucleic acid amplification (OSNA) assay for the diagnosis of lymph node metastasis in patients with non-small cell lung cancer (NSCLC): Results of a multicenter prospective study

OBJECTIVES

The precise and rapid diagnosis of the presence or absence of lymph node (LN) metastasis is essential for deciding upon an appropriate therapeutic strategy for patients with non-small cell lung cancer (NSCLC). We conducted a prospective multicenter clinical trial in Japan to evaluate a rapid, automated and objective assay system, the one-step nucleic acid amplification (OSNA) assay (Sysmex Corp), which targets cytokeratin 19 mRNA, to detect LN metastasis of NSCLC.

MATERIALS AND METHODS

A total of 410 Lymph nodes (LNs) from 111 patients with clinical stage IB to IIIA NSCLC who underwent lung resection with LN dissection were included in this study. The LNs were divided into 4 blocks and examined by either the OSNA assay or a 3-level histological examination. The results of each method were compared and further analyses were performed for discordant cases. The primary endpoint was a concordance rate of more than 85% between the two methods.

RESULTS

The concordance rate between the two methods was 92.7% (95% CI, 89.7-95.0%), with a sensitivity of 79.7% (95% CI, 67.2-89.0%). Discordant results were observed in 30 LNs (5.8%), and were mainly due to a tissue allocation bias and/or contamination by CK19-expressing alveolar cells in LNs.

CONCLUSION

The OSNA assay gave a diagnosis that was as accurate as a 3-level histological examination, which is more detailed than a histological examination in routine clinical practice. The OSNA assay might be useful in intraoperative decision-making in personalized lung cancer surgery based on the LN status.

Comparative analysis between multilevel sectioning with conventional haematoxylin and eosin staining and immunohistochemistry for detecting nodal micrometastases with stage I and II colorectal cancers

Management of patients with stage II colorectal carcinomas remains challenging as 20 - 30% of them will develop recurrence. It is postulated that these patients may harbour nodal micrometastases which are imperceptible by routine histopathological evaluation. The aims of our study were to evaluate (1) the feasibility of multilevel sectioning method utilizing haematoxylin and eosin stain and immunohistochemistry technique with cytokeratin AE1/AE3, in detecting micrometastases in histologically-negative lymph nodes, and (2) correlation between nodal micrometastases with clinicopathological parameters. Sixty two stage I and II cases with a total of 635 lymph nodes were reviewed. Five-level haematoxylin and eosin staining and one-level cytokeratin AE1/AE3 immunostaining were performed on all lymph nodes retrieved. The findings were correlated with clinicopathological parameters. Two (3.2%) lymph nodes in two patients (one in each) were found to harbour micrometastases detected by both methods. With cytokeratin AE1/AE3, we successfully identified four (6.5%) patients with isolated tumour cells, but none through the multilevel sectioning method. Nodal micrometastases detected by both multilevel sectioning and immunohistochemistry methods were not associated with larger tumour size, higher depth of invasion, poorer tumour grade, disease recurrence or distant metastasis. We conclude that there is no difference between the two methods in detecting nodal micrometastases. Therefore it is opined that multilevel sectioning is a feasible and yet inexpensive method that may be incorporated into routine practice to detect nodal micrometastases in centres with limited resources.

Assessment of SHOX2 methylation in EBUS-TBNA specimen improves accuracy in lung cancer staging

BACKGROUND

Endobronchial ultrasound with transbronchial needle aspiration (EBUS-TBNA) is a well-established method to assess mediastinal lymph nodes for lung cancer. However, a proportion of patients require further investigation, due to the low negative predictive value (NPV). The objective of this study was to determine whether the assessment of short stature homeobox 2 (SHOX2) DNA methylation level in lymph node tissue obtained by EBUS-TBNA improves the accuracy of mediastinal staging.

PATIENTS AND METHODS

EBUS-TBNA was carried out for suspicious lymph nodes of 154 patients. Negative or ambiguous histological results were confirmed by surgical means and clinical follow-up over 6 months. EBUS-TBNA was assessed on 80 positive and 85 negative classified lymph nodes and compared with the result of the SHOX2 DNA methylation real-time PCR analysis. Relative methylation measured by delta-delta cycle threshold (ΔΔCt) was used to classify the samples. Clinical performance of the EBUS-TBNA procedure with and without the additional SHOX2 assessment was calculated against the final classification according to the gold standard.

RESULTS

Based on data from 105 patients, an average 80-fold increase in the SHOX2 methylation level was measured for positive compared with negative lymph nodes. SHOX2 results with a ΔΔCt value of <6.5 indicate positive lymph nodes. Applying this molecular analysis to EBUS-TBNA cases, not diagnosed by pathologic assessment, the sensitivity of staging was improved by 17%-99%. The NPV increased from 80% to 99%.

CONCLUSIONS

The combination of EBUS-TBNA and SHOX2 methylation level strongly improves the assessment of the nodal status by identifying additional malignant lesions and confirming benign nodes and therefore avoiding invasive follow-up procedures.

Novel molecular tumor cell markers in regional lymph nodes and blood samples from patients undergoing surgery for non-small cell lung cancer

Introduction

Recent evidence suggests that microscopic lymph node metastases and circulating tumor cells may have clinical importance in lung cancer. The purpose of this study was to identify new molecular markers for tumor cells in regional lymph nodes (LNs) and peripheral blood (PB) from patients with non-small cell lung cancer (NSCLC).

Methods

Candidate markers were selected based on digital transcript profiling and previous literature. KRT19, CEACAM5, EPCAM, DSG3, SFTPA, SFTPC and SFTPB mRNA levels were initially validated by real-time reverse transcription PCR-based quantification in 16 NSCLC tumors and 22 LNs and 12 PB samples from individuals without known cancer. Five of the candidate markers were selected for secondary validation by quantification in parallel tumor biopsies, regional LNs and PB samples from 55 patients undergoing surgery for NSCLC. LN and PB marker status were compared to clinicopathological patient data.

Results

All selected markers except DSG3 were present at high levels in the primary tumors and at very low or non-detectable levels in normal LNs and PB in the first round of validation, indicating a potential for detecting tumor cells in NSCLC patients. The expression profiles of KRT19, CEACAM5, DSG3, SFTPA and SFTPC mRNA were confirmed in the larger group during the secondary validation. Using the highest normal LN level of each marker as threshold, 39 (71%) of the 55 patients had elevated levels of at least one marker in regional LNs. Similarly, 26 (47%) patients had elevated levels of at least one marker in PB. A significantly higher number of patients with adenocarcinomas had positive LN status for these markers, compared with other histological types (P = 0.004).

Conclusions

Several promising molecular tumor cell markers in regional LNs and PB were identified, including the new SFTPA and SFTPC mRNAs. Clinical follow-up in a larger cohort is needed to elucidate their prognostic value.

Occult metastases in lymph nodes predict survival in resectable non-small-cell lung cancer: report of the ACOSOG Z0040 trial

PURPOSE

The survival of patients with non-small-cell lung cancer (NSCLC), even when resectable, remains poor. Several small studies suggest that occult metastases (OMs) in pleura, bone marrow (BM), or lymph nodes (LNs) are present in early-stage NSCLC and are associated with a poor outcome. We investigated the prevalence of OMs in resectable NSCLC and their relationship with survival.

PATIENTS AND METHODS

Eligible patients had previously untreated, potentially resectable NSCLC. Saline lavage of the pleural space, performed before and after pulmonary resection, was examined cytologically. Rib BM and all histologically negative LNs (N0) were examined for OM, diagnosed by cytokeratin immunohistochemistry (IHC). Survival probabilities were estimated using the Kaplan-Meier method. The log-rank test and Cox proportional hazards regression model were used to compare survival of groups of patients. P < .05 was considered significant.

RESULTS

From July 1999 to March 2004, 1,047 eligible patients (538 men and 509 women; median age, 67.2 years) were entered onto the study, of whom 50% had adenocarcinoma and 66% had stage I NSCLC. Pleural lavage was cytologically positive in only 29 patients. OMs were identified in 66 (8.0%) of 821 BM specimens and 130 (22.4%) of 580 LN specimens. In univariate and multivariable analyses OMs in LN but not BM were associated with significantly worse disease-free survival (hazard ratio [HR], 1.50; P = .031) and overall survival (HR, 1.58; P = .009).

CONCLUSION

In early-stage NSCLC, LN OMs detected by IHC identify patients with a worse prognosis. Future clinical trials should test the role of IHC in identifying patients for adjuvant therapy.

Detection of metastatic head and neck squamous cell carcinoma using the relative expression of tissue-specific mir-205

The presence of cervical lymph node metastases in head and neck squamous cell carcinoma (HNSCC) is the strongest determinant of patient prognosis. Owing to the impact of nodal metastases on patient survival, a system for sensitive and accurate detection is required. Clinical staging of lymph nodes is far less accurate than pathological staging. Pathological staging also suffers limitations because it fails to detect micrometastasis in a subset of nodal specimens. To improve the sensitivity of existing means of diagnosing metastatic disease, many advocate the use of molecular markers specific for HNSCC cells. MicroRNA (miRNA) are short noncoding segments of RNA that posttranscriptionally regulate gene expression. Approximately one third of all miRNA will exhibit substantial tissue specificity. Using a quantitative reverse transcription-polymerase chain reaction-based assay, we examined the expression of microRNA-205 (mir-205) across tissues and demonstrated that its expression is highly specific for squamous epithelium. We applied this assay to tissue samples, and we could detect metastatic HNSCC in each positive lymph node specimen, whereas benign specimens did not express this marker. When compared to metastases from other primary tumors, HNSCC-positive lymph nodes were distinguishable by the high expression of this marker. Using an in vitro lymphoid tissue model, we were able to detect as little as one squamous cell in a background of 1 million lymphocytes. By combining the sensitivity of quantitative reverse transcription-polymerase chain reaction with the specificity of mir-205 for squamous epithelium, we demonstrate a novel molecular marker for the detection of metastatic HNSCC.

[Long-term survival of personalized surgical treatment of locally advanced non-small cell lung cancer based on molecular staging]

BACKGROUND AND OBJECTIVE

Approximately 35%-40% of patients with newly diagnosed non-small cell Lung cancer have locally advanced disease. The average survival time of these patients only have 6-8 months with chemotherapy. The aim of this study is to explore and summarize the probability of detection of micrometastasis in peripheral blood for molecular staging, and for selection of indication of surgical treatment, and beneficiary of neoadjuvant chemotherapy and postoperative adjuvant therapy in locally advanced lung cancer; to summarize the long-time survival result of personalized surgical treatment of 516 patients with locally advanced non-small cell lung cancer based on molecular staging methods.

METHODS

CK19 mRNA expression of peripheral blood samples was detected in 516 lung cancer patients by RT-PCR before operation for molecular diagnosis of micrometastasis, personalized molecular staging, and for selection of indication of surgical treatment and the beneficiary of neoadjuvant chemotherapy and postoperative adjuvant therapy in patients with locally advanced nonsmall cell lung cancer invaded heart, great vessels or both. The long-term survival result of personalized surgical treatment was retrospectively analyzed in 516 patients with locally advanced non-small cell lung cancer based on molecular staging methods.

RESULTS

There were 322 patients with squamous cell carcinoma and 194 cases with adenocarcinoma in the series of 516 patients with locally advanced lung cancer involved heart, great vessels or both. There were 112 patients with IIIA disease and 404 cases with IIIB disease according to P-TNM staging. There were 97 patients with M-IIIA disease, 278 cases with M-IIIB disease and 141 cases with III disease according to our personalized molecular staging. Of the 516 patients, bronchoplastic procedures and pulmonary artery reconstruction was carried out in 256 cases; lobectomy combined with resection and reconstruction of partial left atrium was performed in 41 cases; Double sleeve lobectomy combined with resection and reconstruction of super vena cava was carried out in 90 cases; Lobectomy combined with resection and reconstruction of diaphragm was performed in 3 cases; Double sleeve lobectomy combined with resection and reconstruction of partial left atrium was performed in 30 cases; Bronchoplastic procedures and pulmonary artery reconstruction combined with reconstruction of aorta sheath was carried out in 10 cases; Right pneumonectomy combined with resection and reconstruction partial left atrium, total right diaphragm with Dacron, and post cava and right liver vein was performed in one case; Lobectomy combined with resection and reconstruction of carina was carried out in 10 cases; Bronchoplastic procedures and pulmonary artery reconstruction combined with resection and reconstruction of carina and superior vane cava, or combined with superior vena cava and left atrium, or with carina and left atrium was performed in 55 cases in this series. Five patients died of operative complications and the operative mortality was 0.97%. CK19 mRNA expression was found in 141 patients. The positive rate of CK19 mRNA expression was 27.3% in peripheral blood samples in the 516 cases. The positive rates of micrometastasis in peripheral blood was significantly related to histological classification, P-TNM staging and N staging of the cancer (P < 0.05), but not to age, sex, smoking status of the patients, and size of primary tumor, and locations of the tumor (P > 0.05). The median survival time was 43.74 months. The 1, 3, 5 and 10 year survival rates of the 516 cases was 89.1%, 39.3%, 19.8% and 10.4%, respectively. The postoperative survival rate was remarkably correlated with micrometastasis in peripheral blood, histological classification of the tumor, size of primary cancer and lymph mode involvement (P < 0.05). The results of multivariable Cox model analysis showed that "personalized molecular P-TNM staging", micrometastasis in peripheral blood, pathological types of the tumor and mediastinal lymph node metastasis of the cancer were the most significant factors for predicting prognosis in the patients with locally advanced nonsmall lung cancer.

CONCLUSIONS

(1) Micrometastasis was existed in peripheral blood of patients with lung cancer, which can not be detected with conventional methods. (2) Detecting of CK19 mRNA expression in peripheral blood in lung cancer patients can be used for diagnosis of micrometastasis of lung cancer and "molecular staging" and "molecular P-TNM staging" for lung cancer patients. It will be helpful for selection of surgical treatment indication, the beneficiary of neoadjuvant chemotherapy and postoperative adjuvant therapy in the patients with locally advanced non-small cell lung cancer. (3) Personalized surgical treatment can significantly improve prognosis and increase curative rate and long-term survival rate of locally advanced nonsmall cell lung cancer based on personalized molecular staging.

A pragmatic approach to the diagnosis of nodal micrometastases in early stage non-small cell lung cancer

INTRODUCTION

This study was designed to develop a both sensitive and efficient algorithm for detection of lymph node micrometastases and to determine its prognostic impact in patients with early stage non-small cell lung cancer (NSCLC).

METHODS

One hundred seventy patients with NSCLC p stage I and II were included in this study, of which n = 5299 lymph nodes were obtained and submitted to histopathologic analysis. From each patient, a median number of 31 lymph nodes was received (N-1 position: median n = 16; N-2 position: median n = 15). Immunohistochemistry was performed to detect micrometastases unobvious by conventional microscopy using antibodies against cytokeratins (CK) (pan-CK: KL-1, CK 5/6, CK 7) and the epithelial marker Ber-EP4.

RESULTS

In 82 patients (48.2%), micrometastases were revealed in immunohistochemistry staining. KL-1 detected micrometastases in 201 (99.5%) of 202 positive lymph nodes. Subsequently, this resulted in an upstaging in 39 patients (20.5%). Detection of micrometastases in otherwise tumor-free N2-lymph nodes had a significant prognostic impact (mean disease-free survival 21.4 versus 45.3 months, p = 0.022), affecting 4.7% of patients. Survival differences between patients who were upstaged into stage II (N0>N1) and those remaining in stage I were not statistically significant (p = 0.537).

CONCLUSION

Extended workup of N2-lymph nodes using one broad-spectrum keratin marker in otherwise N2-negative lymph nodes may represent a both efficient and sensitive approach to the identification of micrometastases in dissected lymph nodes of patients with early stage NSCLC.

A multi-analyte serum test for the detection of non-small cell lung cancer

BACKGROUND

In this study, we appraised a wide assortment of biomarkers previously shown to have diagnostic or prognostic value for non-small cell lung cancer (NSCLC) with the intent of establishing a multi-analyte serum test capable of identifying patients with lung cancer.

METHODS

Circulating levels of 47 biomarkers were evaluated against patient cohorts consisting of 90 NSCLC and 43 non-cancer controls using commercial immunoassays. Multivariate statistical methods were used on all biomarkers achieving statistical relevance to define an optimised panel of diagnostic biomarkers for NSCLC. The resulting biomarkers were fashioned into a classification algorithm and validated against serum from a second patient cohort.

RESULTS

A total of 14 analytes achieved statistical relevance upon evaluation. Multivariate statistical methods then identified a panel of six biomarkers (tumour necrosis factor-α, CYFRA 21-1, interleukin-1ra, matrix metalloproteinase-2, monocyte chemotactic protein-1 and sE-selectin) as being the most efficacious for diagnosing early stage NSCLC. When tested against a second patient cohort, the panel successfully classified 75 of 88 patients.

CONCLUSIONS

Here, we report the development of a serum algorithm with high specificity for classifying patients with NSCLC against cohorts of various 'high-risk' individuals. A high rate of false positives was observed within the cohort in which patients had non-neoplastic lung nodules, possibly as a consequence of the inflammatory nature of these conditions.

Detection of disseminated tumour cells in mediastinoscopic lymph node biopsies and endobronchial ultrasonography-guided transbronchial needle aspiration in patients with suspected lung cancer

PURPOSE

Ultrasound-guided transbronchial needle aspiration of mediastinal lymph nodes (EBUS-TBNA) is apparently more accurate for cancer diagnosis than standard transbronchial needle aspiration (TBNA), but it is less sensitive than mediastinoscopy. The detection of disseminated tumour cells in transbronchial needle aspiration and mediastinoscopic biopsies could improve staging and might be helpful concerning indications for neoadjuvant regimen. The goal of this study was to develop a quantitative method for the detection of disseminated tumour cells (DTCs) in lymph node samples from patients with suspected lung cancer.

PATIENTS AND METHODS

We compared in a prospective trail EBUS-TBNA (n=58 patients, 86 samples) and mediastinoscopy (n=22 patients, 37 samples) in two largely independent cohorts of lung cancer patients. Eleven patients, 14 samples were analysed using both methods. Patients without evidence of malignant disease were available as controls for EBUS-TBNA (n=20 patients, 28 samples) and mediastinoscopy (n=6 patients, 8 samples). Real-time quantitative mRNA analysis was performed for the cytokeratin 19 (CK19) and MAGE-A genes (MAGE-A 1-6, MAGE-A12) as markers, using a LightCycler 480 instrument.

RESULTS

CK19 mRNA expression in EBUS-TBNA samples was detected in 84/86 (98%) and in 28/28 control samples (100%). After mediastinoscopy 16/37 (43%) samples of lung cancer patients were CK19 mRNA positive while controls showed no CK19 mRNA expression (0/8). MAGE-A expression was detectable in 42/86 (49%) EBUS-TBNA samples and in 13/37 (35%) mediastinoscopy samples. MAGE-A expression was detected in EBUS-TBNA controls in 3/28 (11%) and 1/8 (12%) mediastinoscopy controls. High MAGE-A expression correlated with increased tumour stage.

CONCLUSION

Since CK19 expression was detected in all EBUS-TBNA samples from the control patients, but not in mediastinoscopy samples, we conclude that CK19 is not suitable as a marker for disseminated tumour cells in samples attained by EBUS-TBNA. One possible explanation is a contamination with epithelial cells from the bronchial tubes. MAGE-A genes are promising markers for disseminated tumour cells in lymph nodes in patients with suspected lung cancer which merit further investigation.

The Src inhibitor AZD0530 blocks invasion and may act as a radiosensitizer in lung cancer cells

BACKGROUND

With the emergence of Src inhibitors in clinical trials, improved knowledge of the molecular responses of cancer cells to these agents is warranted. This will facilitate the development of tests to identify patients who may benefit from these agents, allow drug activity to be monitored and rationalize the combination of these agents with other treatment modalities.

METHODS

This study evaluated the molecular and functional effects of Src inhibitor AZD0530 in human lung cancer cells, by Western blotting and reverse transcription-polymerase chain reaction, and by assays for cell viability, migration, and invasion.

RESULTS

Src was activated in four of five cell lines tested and the level corresponded with the invasive potential and the histologic subtype. Clinically relevant, submicromolar concentrations of AZD0530 blocked Src and focal adhesion kinase, resulting in significant inhibition of cell migration and Matrigel invasion. Reactivation of STAT3 and up-regulation of JAK indicated a potential mechanism of resistance. AZD0530 gave a potent and sustained blockage of AKT and enhanced the sensitivity to irradiation.

CONCLUSIONS

The results indicated that AZD0530, aside from being a potent inhibitor of tumor cell invasion which could translate to inhibition of disease progression in the clinic, may also lower resistance of lung cancer cells to pro-apoptotic signals.

Establishment of a multi-analyte serum biomarker panel to identify lymph node metastases in non-small cell lung cancer

INTRODUCTION

In non-small cell lung cancer (NSCLC), the presence of locoregional lymph node metastases remains the most important prognostic factor and significantly guides treatment regimens. Unfortunately, currently-available noninvasive staging modalities have limited accuracy. The objective of this study was to create a multianalyte blood test capable of discriminating a patient's true (pathologic) nodal status preoperatively.

METHODS

Pretreatment serum specimens collected from 107 NSCLC patients with localized disease were screened with 47 biomarkers implicated in disease presence or progression. Multivariate statistical algorithms were then used to identify the optimal combination of biomarkers for accurately discerning each patient's nodal status.

RESULTS

We identified 15 candidate biomarkers that met our criteria for statistical relevance in discerning a patient's preoperative nodal status. A 'random forest' classification algorithm was used with these parameters to define a 6-analyte panel, consisting of macrophage inflammatory protein-1alpha, carcinoembryonic antigen, stem cell factor, tumor necrosis factor-receptor I, interferon-gamma, and tumor necrosis factor-alpha, that was the optimum combination of biomarkers for identifying a patient's pathologic nodal status. A Classification and Regression Tree analysis was then created with this panel that was capable of correctly classifying 88% of the patients tested, relative to the pathologic assessments. This value is in contrast to our observed 85% classification rate using conventional clinical methods.

CONCLUSIONS

This study establishes a serum biomarker panel with efficacy in discerning preoperative nodal status. With further validation, this blood test may be useful for assessing nodal status (including occult disease) in NSCLC patients facing tumor resection therapy.

Multiclass cancer classification by support vector machines with class-wise optimized genes and probability estimates

We investigate the multiclass classification of cancer microarray samples. In contrast to classification of two cancer types from gene expression data, multiclass classification of more than two cancer types are relatively hard and less studied problem. We used class-wise optimized genes with corresponding one-versus-all support vector machine (OVA-SVM) classifier to maximize the utilization of selected genes. Final prediction was made by using probability scores from all classifiers. We used three different methods of estimating probability from decision value. Among the three probability methods, Platt's approach was more consistent, whereas, isotonic approach performed better for datasets with unequal proportion of samples in different classes. Probability based decision does not only gives true and fair comparison between different one-versus-all (OVA) classifiers but also gives the possibility of using them for any post analysis. Several ensemble experiments, an example of post analysis, of the three probability methods were implemented to study their effect in improving the classification accuracy. We observe that ensemble did help in improving the predictive accuracy of cancer data sets especially involving unbalanced samples. Four-fold external stratified cross-validation experiment was performed on the six multiclass cancer datasets to obtain unbiased estimates of prediction accuracies. Analysis of class-wise frequently selected genes on two cancer datasets demonstrated that the approach was able to select important and relevant genes consistent to literature. This study demonstrates successful implementation of the framework of class-wise feature selection and multiclass classification for prediction of cancer subtypes on six datasets.

Principles of staging as applied to nonsmall cell lung cancer

PURPOSE OF REVIEW

To review the principles of staging cancer as applied to nonsmall cell lung cancer.

RECENT FINDINGS

The current staging system is under review for update. It is timely to review the principles of staging cancer to see how the nonsmall cell lung cancer staging system can be improved. Staging systems should predict prognosis, and guide therapy and research. Based on newer data the next staging system will likely incorporate more categories for tumor size and metastatic disease. Nodal staging may need to distinguish between single station N2 disease and multiple N2 station involvement, as there is some evidence that those with bulky multiple station N2 disease do worse. Histology is increasingly used to guide therapy and there are data that it can affect prognosis.

SUMMARY

How we stage patients with nonsmall cell lung cancer is about to change. The most important changes are to tumor size classification and classification of metastatic disease. Better standardization of measurements for tumor staging may further improve the utility of staging.

Gene Expression Studies Demonstrate that the K-ras/Erk MAP Kinase Signal Transduction Pathway and Other Novel Pathways Contribute to the Pathogenesis of Cumene-induced Lung Tumors

National Toxicology Program (NTP) inhalation studies demonstrated that cumene significantly increased the incidence of alveolar/bronchiolar adenomas and carcinomas in B6C3F1 mice. Cumene or isopropylbenzene is a component of crude oil used primarily in the production of phenol and acetone. The authors performed global gene expression analysis to distinguish patterns of gene regulation between cumene-induced tumors and normal lung tissue and to look for patterns based on the presence or absence of K- ras and p53 mutations in the tumors. Principal component analysis segregated the carcinomas into groups with and without K- ras mutations, but failed to separate the tumors based on p53 mutation status. Expression of genes associated with the Erk MAP kinase signaling pathway was significantly altered in carcinomas with K- ras mutations compared to tumors without K- ras mutations or normal lung. Gene expression analysis also suggested that cumene-induced carcinomas with K- ras mutations have greater malignant potential than those without mutations. In addition, significance analysis of function and expression (SAFE) demonstrated expression changes of genes regulated by histone modification in carcinomas with K- ras mutations. The gene expression analysis suggested the formation of alveolar/bronchiolar carcinomas in cumene-exposed mice typically involves mutation of K- ras, which results in increased Erk MAP kinase signaling and modification of histones.

Global gene expression analysis reveals specific patterns of cell junctions in non-small cell lung cancer subtypes

Non-small cell lung cancer (NSCLC) can be classified into the major subtypes adenocarcinoma (AC) and squamous cell carcinoma (SCC). Although explicit molecular, histological and clinical characteristics have been reported for both subtypes, no specific therapy exists so far. However, the characterization of suitable molecular targets holds great promises to develop novel therapies in NSCLC. In the present study, global gene expression profiling of 58 human NSCLC specimens revealed large transcriptomic differences between AC and SCC subtypes: more than 1700 genes were found to be differentially expressed. The assignment of these genes to biological processes pointed to the deregulation of distinct sets of genes coding for cell junctions in both tumor subtypes. We focused on 17 cell adhesion genes and 11 reported marker genes for epithelial-mesenchymal transition (EMT), and investigated their expression in matched tumor-normal specimens by quantitative real-time PCR. The majority of the cell adhesion genes was significantly up-regulated in at least one tumor subtype compared to normal tissue, predominantly desmosomes and gap junctions in SCC, and tight junctions in AC. The higher expression of EMT marker transcripts in tumor specimens suggested a large potential for invasion and migration processes in NSCLC. Our results indicate that AC and SCC in the lung are characterized by the expression of distinct sets of cell adhesion molecules which may represent promising targets for novel specific therapies.

Diagnostic surgical pathology in lung cancer: ACCP evidence-based clinical practice guidelines (2nd edition)

OBJECTIVE

The objective of this study was to provide evidence-based background and recommendations for the development of American College of Chest Physicians guidelines for the diagnosis and management of lung cancer.

METHODS

A systematic search of the medical and scientific literature using MEDLINE, MDCONSULT, UpToDate, Cochrane Library, NCCN guidelines, and NCI/NIH search engines was performed for the years 1990 to 2006 to identify evidence-based and consensus guidelines. The search was limited to literature on humans and articles in the English language.

RESULTS

The pathologic assessment of lung cancers is based on a set of well-accepted findings, including histologic type, tumor size and location, involvement of visceral pleura, and extension to regional and distant lymph nodes and organs. Bronchial-based incipient neoplasia needs to be recognized both grossly and microscopically because these lesions may be multifocal and represent multistep carcinogenesis and may be amenable to therapy. Cytologic assessment of the individual with no symptoms is, as yet, of insufficient clinical benefit for screening of lung cancer. In challenging situations of pathologic differential diagnosis, additional studies may provide information that enables the separation of distinct tumor types. Pathobiological and molecular biological studies may yield prognostic and predictive information for clinical management and should be considered as part of protocol studies. Enhanced pathologic and molecular techniques may identify the presence of micrometastatic disease within lymph nodes; however, the clinical utility of these approaches is still unresolved. Intraoperative consultations have high diagnostic accuracy and may aid ongoing treatment and management decisions.

CONCLUSIONS

Pathologic assessment is a crucial component for the diagnosis, management, and prognosis of lung cancer. Selective diagnostic techniques and decision analysis will increase diagnostic accuracy. Cytologic screening, molecular characterization of tumors, and micrometastatic analysis are potential but not yet proved modalities for the evaluation of lung cancers.

Optimal markers for real-time quantitative reverse transcription PCR detection of circulating tumor cells from melanoma, breast, colon, esophageal, head and neck, and lung cancers

BACKGROUND

The detection of circulating tumor cells (CTCs) may prove useful for screening, prognostication, and monitoring of response to therapy. However, given the large background of circulating cells, it is probably necessary to detect 1 cancer cell in >10(6) leukocytes. Although reverse transcription (RT)-PCR is potentially sensitive and specific enough to achieve this goal, success will require the use of appropriate mRNA markers. The goal of this study was to identify optimal marker combinations for detection of CTCs.

METHODS

An extensive literature and internet database survey was conducted to identify potential markers. We then used real-time quantitative RT-PCR to test for expression of selected potential markers in tissue samples from primary tumors of breast, colon, esophagus, head and neck, lung, and melanoma and normal blood samples. Markers with high expression in tumors and a median 1000-fold lower expression in normal blood were considered potentially useful for CTC detection and were tested further in an expanded sample set.

RESULTS

A total of 52 potential markers were screened, and 3-8 potentially useful markers were identified for each tumor type. The mRNAs for all but 2 markers were found in normal blood. Marker combinations were identified for each tumor type that had a minimum 1000-fold higher expression in tumors than in normal blood.

CONCLUSIONS

Several mRNA markers may be useful for RT-PCR-based detection of CTCs from each of 6 cancer types. Quantification of these mRNAs is essential to distinguish normal expression in blood from that due to the presence of CTCs. Few markers provide adequate sensitivity individually, but combinations of markers may produce good sensitivity for detection of the presence of these 6 neoplasms.

Metastasis: recent discoveries and novel treatment strategies

Most cancer deaths are due to the development of metastases, hence the most important improvements in morbidity and mortality will result from prevention (or elimination) of such disseminated disease. Some would argue that treatments directed against metastasis are too late because cells have already escaped from the primary tumour. Such an assertion runs contrary to the significant but (for many common adult cancers) fairly modest improvements in survival following the use of adjuvant radiation and chemotherapy designed to eliminate disseminated cells after surgical removal of the primary tumour. Nonetheless, the debate raises important issues concerning the accurate early identification of clonogenic, metastatic cells, the discovery of novel, tractable targets for therapy, and the monitoring of minimal residual disease. We focus on recent findings regarding intrinsic and extrinsic molecular mechanisms controlling metastasis that determine how, when, and where cancers metastasise, and their implications for patient management in the 21st century.