Association of CK19 mRNA detection of occult cancer cells in mediastinal lymph nodes in non-small cell lung carcinoma and high risk of early recurrence

Incorporating Lymph Node Size at CT as an N1 Descriptor in Clinical N Staging for Lung Cancer

Background The ninth edition of the TNM classification for lung cancer revised the N2 categorization, improving patient stratification, but prognostic heterogeneity remains for the N1 category. Purpose To define the optimal size cutoff for a bulky lymph node (LN) on CT scans and to evaluate the prognostic value of bulky LN in the clinical N staging of lung cancer. Materials and Methods This retrospective study analyzed patients who underwent lobectomy or pneumonectomy for lung cancer between January 2013 and December 2021, divided into development (2016-2021) and validation (2013-2015) cohorts. The optimal threshold for a bulky LN was defined based on the short-axis diameter of the largest clinically positive LN at CT. Prognostic differences according to presence of bulky LN in cN1 category for overall survival (OS) were evaluated using multivariable Cox analysis. Survival discrimination was assessed using the Harrell concordance index (C-index). Results A total of 3426 patients (mean age, 64.0 years ± 9.3 [SD]; 1837 male) and 1327 patients (mean age, 63.0 years ± 9.7; 813 male) were included in the development and validation cohorts, respectively. The cutoff size for a bulky LN was established at 15 mm, and the presence of bulky LN was an independent risk factor for OS (hazard ratio [HR], 1.54; 95% CI: 1.10, 2.16; P = .01). In the development and validation cohorts, the cN1-bulky group had higher mortality risk than the cN1-nonbulky group (HR, 2.82 [95% CI: 1.73, 4.58; P < .001]; 2.29 [95% CI: 1.34, 3.92; P = .002], respectively). The bulky LN descriptor improved prognostic discrimination within the cN1 category compared with the current staging (C-index from 0.50 to 0.60 and to 0.58 in the development and validation cohorts [P < .001, P = .006], respectively]). Conclusion Defining bulky LN with a size cutoff of 15 mm was an effective descriptor in the clinical staging of N1 lung cancer. © RSNA, 2025 Supplemental material is available for this article. See also the editorial by Horst in this issue.

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 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.

Immunohistochemical detection of lymph node-DTCs in patients with node-negative HNSCC

This study was performed to systematically assess the prevalence, topography and prognostic impact of disseminated tumor cells (DTCs) in lymph nodes (LN) of patients with primary, regional and distant metastasis-free head and neck squamous cell carcinoma (HNSCC) who underwent resection with elective neck dissection. From the routinely processed resection specimen, we could prospectively analyze a total of 1.137 exactly mapped LNs of 50 pN0-HNSCC patients, classified as tumor free by routine histopathology. Three immunohistochemistry (IHC) assays using antibodies directed against CK5/14, a broad spectrum of CKs (1-8, 10, 14-16 and 19), and CD44v6, respectively, were applied on 4.190 LN sections to detect DTCs. The IHC results were correlated with clinicopathologic parameters and clinical follow-up data. We detected seven micrometastases (MM) in five patients and 31 DTCs in 12 patients. Overall, 15 (30%) patients were positive for DTCs or MMs. Strikingly, the anatomical distribution of LN affected with DTCs was not random, but was dependent on the lateralization of the primary tumor and clustered significantly most proximal to the primary tumor. None of the investigated patients developed loco-regional lymphatic or distant metastasis during the mean follow-up period of 71 months. Our results reveal clinically occult tumor cell dissemination as an early and frequent event in HNSCC. Considering that higher rates of recurrences in therapeutic LN dissection concepts have been reported than in elective neck dissection strategies, our DTC-data support to perform elective neck dissections, since they appear to be effective in preventing loco-regional lymphatic recurrence from LN DTCs or MMs.

Prognostic Significance of Cytokeratin 19 and Squamous Cell Cancer Antigen in Histologically Negative Sentinel Lymph Nodes of Cervical Squamous Cell Carcinoma

OBJECTIVE

The aim of the study was to evaluate the prognostic value of positive cytokeratin 19 (CK19) and squamous cell cancer antigen (SCCAg) expression in histologically negative sentinel lymph nodes after surgery for cervical squamous cell carcinoma.

METHODS

Immunohistochemistry was performed to detect the expression of CK19 and SCCAg using polyclonal antibody on 149 pair of formalin-fixed, paraffin-embedded cervical squamous cell carcinoma and histologically negative sentinel lymph node tissue samples, and results were compared with data from the prospectively registry of cervical squamous cell carcinoma by univariate and multivariate logistic regression model focusing specifically on recurrence. The survival was assessed by the Kaplan-Meier method and proportional hazards model.

RESULTS

Cytokeratin 19 and SCCAg expression in histologically negative sentinel lymph nodes were documented in 15.4% (n = 23) and 20.8% (n = 31) patients and were associated with a higher incidence of tumor progression and poorer disease-free survival (DFS, P < 0.05). Multivariate logistic regression analysis demonstrated that CK19 (P = 0.001) and SCCAg (P = 0.001) expression in histologically negative sentinel lymph nodes, International Federation of Gynecology and Obstetrics staging (P = 0.000), and cervical stroma infiltration depth (P = 0.005) were independent predictive factors for recurrence. The proportional hazards model identified CK19 (P = 0.001) and SCCAg (P = 0.005) expression in histologically negative sentinel lymph nodes, International Federation of Gynecology and Obstetrics staging (P = 0.003), and cervical stroma infiltration depth (P = 0.005), as independently related to DFS. Using subgroup analysis, we found that the CK19+/SCCAg + subgroup has the poorest prognosis, whereas the CK19-/SCCAg - subgroup has the best prognosis (P = 0.000).

CONCLUSIONS

Immunohistochemical assessment of both CK19 and SCCAg status in histologically negative sentinel lymph nodes may be a valuable approach for predicting recurrence and survival after curative surgery for cervical squamous cell carcinoma.

Detection of disseminated tumor cells in lymph nodes from patients with early stage non-small cell lung cancer

BACKGROUND

The regional lymph node involvement is a major prognostic factor in patients with non-small cell lung cancer (NSCLC) undergoing surgical resection. Disease relapse is common, suggesting that early disseminated disease is already present in the regional lymph nodes at the time of surgery, and that the current nodal staging classification might be suboptimal. Early detection of disseminated tumor cells (DTCs) in lymph nodes could potentially enable identification of subcategories of patients with high risk of disease relapse.

METHOD

Lymph node samples were collected from 128 NSCLC patients at the time of surgery and the presence of DTCs determined by immunomagnetic selection (IMS) using the MOC31 antibody recognizing EpCAM. Results obtained with IMS were compared to the pathological staging obtained by histopathology. Associations between the presence of DTCs and clinicopathological variables and patient outcome were investigated.

RESULTS

DTCs were detected in 40 % of the lymph node samples by IMS. Their presence was significantly associated with pN status as assessed by histopathology, and samples from 83 % of the patients with lymph node metastases (pN1-2) had detectable DTCs. In the group of patients who were negative for lymph node metastases by standard histopathology (pN0) DTCs were detected in 32 %. The presence of DTCs was not associated with any other clinicopathological variables. Patients with IMS-positive samples showed decreased relapse free survival compared to patients with IMS-negative samples, but the difference was not statistically significant. The pN status was significantly associated with both relapse free and overall survival, but the presence of DTCs had no prognostic impact in the subcategory of patients with pN0 status.

CONCLUSION

Our findings do not support further development of lymph node DTC detection for clinical use in early stage NSCLC.

Recurrence after surgery in patients with NSCLC

Surgery remains the only potentially curative modality for early-stage non-small cell lung cancer (NSCLC) patients and tissue availability is made possible. However, a proportion of lung cancer patients develop recurrence, even after curative resection. This review discusses the superiority of surgery, the reasons for recurrence, the timing and pattern of recurrence, the identification of factors related to recurrence, current provisions for treatment and perspectives about surgery for patients with NSCLC.

[The prognostic value of micrometastasis in non-small cell lung cancer]

肺癌是我国目前发病率和死亡率最高的恶性肿瘤。非小细胞肺癌（non-small cell lung cancer, NSCLC）占肺癌的80%-85%。诊断时的分期是NSCLC主要的预后因子，也是治疗模式选择的重要依据。然而，完全性切除术后的Ⅰ期的NSCLC仍有25%-30%的复发率。这部分复发的患者可能早期就存在局部和（或）远处的隐匿性转移。因此，很多研究开始对NSCLC患者进行微转移的检测，并评估其预后价值。本文总结了近年来的相关研究，并就NSCLC的淋巴结微转移、骨髓微转移、胸膜腔微转移及外周血微转移的预后作用进行综述。

The stage classification of lung cancer: Diagnosis and management of lung cancer, 3rd ed: American College of Chest Physicians evidence-based clinical practice guidelines

The current Lung Cancer Stage Classification system is the seventh edition, which took effect in January 2010. This article reviews the definitions for the TNM descriptors and the stage grouping in this system.

Multiplex PCR-based detection of circulating tumor cells in lung cancer patients using CK19, PTHrP, and LUNX specific primers

INTRODUCTION

The aim of this study was to develop a multiplex polymerase chain reaction (PCR)-based method for detection of circulating tumor cells in peripheral blood of lung cancer (LC) patients.

PATIENTS AND METHODS

Peripheral blood was collected from 71 healthy donors and 125 LC patients at different pathological stages. Samples were analyzed using multiplex PCR, and specific primers for CK19, PTHrP, and LUNX mRNA. The sensitivity of our method was set at 10 LC cells (A549 cells) in 3 mL of peripheral blood of healthy donors using spiking experiments.

RESULTS

The detection rates in LC patients for CK19, PTHrP, and LUNX were 45.6%, 64.8%, and 28%, and in healthy individuals were 7%, 7%, and 5.6%, respectively. Overall, our method produced 77.8% positive detections for at least 1 molecular marker. Twenty-eight (22.2%) were negative for expression of all markers, 39 (31.2%) were positive for expression of 1 marker, 42 (33.6%) were positive for expression of 2 markers, and 17 (13.6%) were positive for expression of all 3 markers. Detection of CK19 mRNA expression positively correlated with LC stage and distant metastases. PTHrP mRNA detection correlated positively with LC stage, presence of bone metastasis, and squamous cell carcinoma, and LUNX mRNA detection correlated with lymph node involvement. Combined detection of 2 or 3 markers was significantly correlated with metastatic disease, and negative detection of all 3 molecular markers was correlated with early stage nonmetastatic disease.

CONCLUSION

Multiple PCR-based detection of CK19, PTHrP, and LUNX mRNA expression provides useful information for disease stage and dissemination in LC patients.

Gene diagnosis of micrometastases in regional lymph nodes of patients with stage I non-small cell lung cancer: impact on staging and prognosis

PURPOSE

The long-term survival of patients with completely resected stage I non-small cell lung cancer (NSCLC) is not optimal because of undetected lymph node micrometastasis at the time of surgery. The aim of this study is to evaluate the role of survivin and livin mRNA expression in histopathologically negative lymph nodes of stage I NSCLC patients as markers of micrometastasis.

METHODS

Clinical data and tissue samples of primary tumor and lymph nodes were collected from 44 patients with stage I NSCLC. Reverse-transcriptase-PCR (RT-PCR) was used to detect survivin and livin mRNA expression in these tumor and lymph node samples.

RESULTS

Survivin mRNA was detected in all tumors, and livin mRNA was detectable in 39 of the 44 primary tumors. The cut-off values of survivin and livin mRNA levels for diagnosing micrometastasis in lymph nodes were set up according to the expression of survivin and livin mRNA in control lymph nodes. Fifteen (34.1 %) of 44 stage I NSCCL patients had micrometastasis in lymph nodes by survivin and/or livin mRNA positive expression. Survival analysis showed higher rate of cancer recurrences and tumor-related death in patients with lymph node micrometastasis (P < 0.001 and P = 0.001, respectively). Tumor-free survival and overall survival were significantly worse in patients with lymph node micrometastasis compared with those without such micrometastasis (P = 0.007 and P = 0.01, respectively).

CONCLUSION

RT-RCR assay for survivin and livin mRNA can be considered as useful diagnostic tool for the detection of lymph node micrometastasis for stage I NSCLC patients.

Clinical significance of micrometastases in lymph nodes from laryngeal squamous cell carcinoma

OBJECTIVE

To assess the role of lymph nodes micrometastases in laryngeal squamous cell carcinoma and correlate the results with survival.

METHODS

We performed immunohistochemical analyses of lymph nodes after the resection of 126 patients for detection of micrometastasis. The lymph nodes were examined with hematoxylin and eosin (HE)-stained and cytokeratin (CK) antibodies AE1/AE3 stained. Recurrences and metastases were recorded during follow-up. The Kaplan-Meier method was used for survival analysis.

RESULTS

In total, 126 patients underwent neck dissection. Forty-one patients were HE positive (group 1), while 85 were HE negative. Thirty-three of these HE negative patients were CK positive (group 2), while 52 were CK negative (group 3). Patients in groups 2 and 3 had a different outcome (P < .001). Survival was worse in patients in group 2 (10-year survival of 52.12% vs 81.16% in group 3, P < .01).

CONCLUSION

Immunohistochemical analysis is an efficient way to detect micrometastasis in lymph nodes after the resection of conventionally node-negative patients. The detection of CK-positive cells is an independent prognostic factor, and more aggressive treatment should be indicated in these patients.

Clinical meaning of age-related expression of fecal cytokeratin 19 in colorectal malignancy

Background

Colorectal cancer (CRC) is one of the leading causes of malignant death worldwide. Because young age of onset is often considered a poor prognostic factor for CRC, it is important to identify the poor outcomes of CRC in a younger population and to consider an aggressive approach by implementing early treatment. Our aim was to specifically quantify the fecal cytokeratin 19 (CK19) transcript from CRC patients and investigate its correlation with clinical stage, tumor malignancy, and age.

Methods

The quantitation of fecal CK19 transcript was determined by a quantitative real-time reverse transcription polymerase chain in 129 CRC patients (45 younger than 60 years at diagnosis) and 85 healthy controls. The levels of CK19 protein were examined both in colonic cell lines and tissues.

Results

The analysis of 45 younger CRC patients (age ≤ 60 years) revealed that patients at the M1 stage had significantly higher expression levels of fecal CK19 mRNA when compared with healthy controls (p < 0.001) and patients at the M0 stage (p = 0.004). Additionally, the degree of consistency between the mean level of fecal CK19 mRNA and the distant metastatic rate in each age interval was up to 89% (p = 0.042).

Conclusion

These results indicate that high levels of fecal CK19 mRNA represent a potential marker for colorectal malignancy and for aggressive treatment of younger CRC patients.

Serum vascular endothelial growth factor levels in patients with non-small cell lung cancer and its relations to the micrometastasis in peripheral blood

To examine the relationship between the levels of the serum vascular endothelial growth factor (VEGF) and the micrometastasis of peripheral blood in patients with non-small cell lung cancer (NSCLC), 108 NSCLC patients, including 40 patients with benign lung diseases and 30 healthy controls, were investigated. The serum VEGF levels were detected by ELISA and CK19 mRNA in peripheral blood by reverse transcriptase-polymerase chain reaction (RT-PCR). In NSCLC group, the serum VEGF levels and the positive rate of CK19 mRNA in peripheral blood were 479.8+/-268.5 pg/mL and 66.7%, which were significantly higher than those of the other two groups respectively (P<0.01), and both of them were increased significantly with the progression of clinical stage of the tumors (P<0.01). Serum VEGF levels as well as the positive rate of CK19 mRNA in different pathological types of lung cancer had no significant differences (P>0.05). Serum VEGF levels in the patients positive for CK19 mRNA was 561.7+/-325.6 pg/mL. It is significantly higher than that in the negative patients (P<0.01). There existed a significant correlation between serum VEGF levels and expression of CK19 mRNA in peripheral blood in NSCLC patients (P<0.001). The detection of serum VEGF levels and CK19 mRNA in peripheral blood is helpful in judging the condition and the prognosis of NSCLC patients, and serum VEGF levels and CK19 mRNA are independent of the pathological types of lung cancer. The micrometastasis in peripheral blood of NSCLC patients is significantly associated with serum VEGF levels.

Expression of melanoma-antigen-A (MAGE-A) in disseminated tumor cells in regional lymph nodes of patients with operable non-small cell lung cancer

PURPOSE

Single disseminated tumor cells are detectable in regional lymph nodes of 30-50% patients with early-stage non-small cell lung cancer (NSCLC). This study investigated if these disseminated tumor cells express MAGE-A and thus might be targeted by adjuvant anti-MAGE-A immunotherapies.

EXPERIMENTAL DESIGN

Lymph nodes of 32 consecutive patients without neoadjuvant therapy were removed by systematic lymphadenectomy during resection of NSCLC. One-hundred of these lymph nodes were cut into two equal halves which were examined using either routine histo-pathology or quantitative reverse transcriptase PCR (qRT-PCR). qRT-PCR amplification of cytokeratin 19 transcripts was applied for the detection of disseminated tumor cells. Expression of MAGE-A was analyzed using one single primer pair amplifying subgroups MAGE-A1 to -A6 in one qRT-PCR reaction.

RESULTS

Ninety-four (94%) lymph nodes were tumor-free by histo-pathology. qRT-PCR detected disseminated tumor cells in 26 (28%) of these lymph nodes resulting in 19 (59%) patients with disseminated tumor cells. All of the remaining 6 lymph nodes that were judged by the pathologist to contain tumor cells exhibited CK19 transcripts. Fifteen (46%) lymph nodes with disseminated tumor cells contained MAGE-A transcripts resulting in 12 (37%) patients with disseminated tumor cells which expressed MAGE-A. There was no correlation between clinico-pathological parameters and the occurrence of disseminated tumor cells or their MAGE-A expression.

CONCLUSIONS

Since 37% of patients with operable NSCLC harbored disseminated tumor cells that expressed MAGE-A, only these patients might benefit from adjuvant immunotherapies directed against MAGE-A1 to -A6. This study may provide a basis for the preselection of patients to be included in such immunotherapy trials after resection of NSCLC.

Clinical significance of micrometastases detection in lymph nodes from head and neck squamous cell carcinoma

OBJECTIVE: Study the clinical relevance of micrometastases in head and neck squamous cell carcinoma (HNSCC).

METHODS: We reviewed the outcome of 31 patients who underwent neck dissection for HNSCC with lymph node analysis by cytokeratin 19 real-time Taqman polymerase chain reaction (CK19RT-PCR) for detection of micrometastasis. Fifteen patients were N+ on histopathology (group 1) and 16 were N-; nine of these 16 patients were CK19RT-PCR positive (group 2), whereas seven were negative (group 3). Local and neck recurrences, metastases, and other tumour sites were recorded during follow-up.

RESULTS: Five patients in group 1, eight patients in group 2, and one patient in group 3 experienced a tumor-related event. N-patients in groups 2 and 3 had a different outcome ( P < 0.01).

CONCLUSION: It is suggested that CK19RTPCR detection of micrometastasis in lymph nodes could be of significant prognostic value in HNSCC, because more aggressive treatment could be indicated in these patients.

Diagnostic utility of LunX mRNA in peripheral blood and pleural fluid in patients with primary non-small cell lung cancer

Background

Progress in lung cancer is hampered by the lack of clinically useful diagnostic markers. The goal of this study was to provide a detailed evaluation of lung cancer tumor markers indicative of molecular abnormalities and to assess their diagnostic utility in non-small cell lung cancer (NSCLC) patients.

Methods

Quantitative real-time RT-PCR was used to determine LunX, CK19, CEA, VEGF-C and hnRNP A2/B1 mRNA levels in peripheral blood and pleural fluid from NSCLC patients, compared with those from patients with other epithelial cancer (esophagus cancer and breast cancer), benign lung disease (pneumonia and tuberculo pleurisy) and from healthy volunteers.

Results

In peripheral blood LunX mRNA was detectable in 75.0% (33/44) of patients with NSCLC, but not in patients with other epithelial cancer (0/28), benign lung disease (0/10) or in healthy volunteers (0/15). In contrast, all other genetic markers were detected in patients with either NSCLC, other epithelia cancer or benign lung disease, and in healthy volunteers. The expression level and positive rate of LunX mRNA in peripheral blood correlated with the pathologic stage of NSCLC (P < 0.001 and P = 0.010 respectively). Furthermore, LunX mRNA was detected in 92.9% (13/14) of malignant pleural fluid samples and was the only marker whose expression level was significantly different between malignant and benign pleural fluid (P < 0.001). Additionally, expression of LunX mRNA in the peripheral blood of NSCLC patients decreased shortly after clinical treatment (P = 0.005).

Conclusion

Of several commonly used genetic markers, LunX mRNA is the most specific gene marker for lung cancer and has potential diagnostic utility when measured in the peripheral blood and pleural fluid of NSCLC patients.

Detection of MAGE-A Transcripts in Bone Marrow Is an Independent Prognostic Factor in Operable Non–Small-Cell Lung Cancer

PURPOSE

MAGE-A gene expression in humans is mostly restricted to tumor cells, and the role of MAGE-A transcripts and peptides as diagnostic markers and therapeutic targets is currently under investigation. Thus far, the clinical relevance of MAGE-A transcripts as marker for disseminated tumor cells in bone marrow of patients with operable lung cancer without overt metastases is still unclear.

EXPERIMENTAL DESIGN

Preoperative bone marrow aspirates from 50 consecutive patients with operable non-small-cell lung cancer free of distant metastases (i.e., pT(1-4) pN(0-2) M(0) R(0)) were admitted to the study. Each bone marrow sample was divided and examined using multimarker MAGE-A reverse transcription-PCR (RT-PCR) and immunocytochemical staining with the anti-pancytokeratin antibody A45-B/B3. Multimarker MAGE-A RT-PCR consisted of multiple subtype-specific nested RT-PCRs with primers for MAGE-A1, MAGE-A2, MAGE-A3/6, MAGE-A4, and MAGE-A12. The median follow-up duration was 92 months (range, 18-110 months).

RESULTS

Twenty-six (52%) lung cancer patients harbored MAGE-A transcripts in their bone marrow, as opposed to none of the 30 healthy controls tested. In all 7 patients with immunocytochemically positive bone marrow, MAGE-A transcripts were also detected. All different MAGE-A subtypes (MAGE-A1, MAGE-A2, MAGE-A3/6, MAGE-A4, and MAGE-A12) were observed. Sixty-five percent of patients with MAGE-A transcripts in bone marrow exhibited only one subtype. Univariate (P = 0.03, log-rank-test) and multivariate survival analysis showed that MAGE-A transcripts in bone marrow were associated with poor outcome in pN(0) patients (P = 0.02; relative risk, 7.6).

CONCLUSIONS

Detection of MAGE-A transcripts in bone marrow predicts an unfavorable outcome in patients with early-stage operable lung cancer. This finding indicates that MAGE-A transcripts are clinically relevant markers of micrometastatic spread in lung cancer and supports further investigation of MAGE-A as potential future therapeutic target.

The Future in Diagnosis and Staging of Lung Cancer

Lung cancers at the same stage of disease have markedly different rates of disease progression. In this review, we will address current molecular techniques which provide new opportunities according to diagnosis, prediction of survival or selection of therapy. New molecular techniques might be helpful in TNM staging and lead to additional individual prognostic information. A revised TNM system could include a TNM component and a molecular supplemental component allowing new markers to be evaluated without undermining the value of classic TNM staging. Furthermore, molecular techniques might be helpful in the early or differential diagnosis of lung cancer. Since many new targeted agents are effective only if their respective molecular markers are mutated or expressed at sufficient levels, DNA-based or RNA-based techniques have the potential to influence treatment selection in the future. Overall, we can expect that molecular markers will contribute to a more personalized lung cancer treatment.

Detection of occult carcinomatous diffusion in lymph nodes from head and neck squamous cell carcinoma using real-time RT-PCR detection of cytokeratin 19 mRNA

The aim of the present study was to evaluate the occult lymph node carcinomatous diffusion in head and neck squamous cell carcinoma (HNSCC). A total of 1328 lymph nodes from 31 patients treated between 2004 and 2005 were prospectively evaluated by routine haematoxylin–eosin–safran (HES) staining, immunohistochemistry (IHC) and real-time Taqman reverse–transcriptase polymerase chain reaction (real-time RT–PCR) assay. Amplification of cytokeratin 19 (CK19) mRNA transcripts using real-time RT–PCR was used to quantify cervical micrometastatic burden. The cervical lymph node metastatic rates determined by routine HES staining and real-time RT–PCR assay were 16.3 and 36.0%, respectively (P<0.0001). A potential change in the nodal status was observed in 13 (42.0%) of the 31 patients and an atypical pattern of lymphatic spread was identified in four patients (12.9%). Moreover, CK19 mRNA expression values in histologically positive lymph nodes were significantly higher than those observed in histologically negative lymph nodes (P<0.0001). These results indicate that real-time RT–PCR assay for the detection of CK19 mRNA is a sensitive and reliable method for the detection of carcinomatous cells in lymph nodes. This type of method could be used to reassess lymph node status according to occult lymphatic spread in patients with HNSCC.

Molecular mechanisms of metastasis

A major topic covered at the First International Symposium on Cancer Metastasis and the Lymphovascular System was the molecular mechanisms of metastasis. This has become of major interest in recent years as we have discovered new metastasis-related genes and gained understanding of the molecular events of lymphatic metastasis. The symposium covered new aspects and important questions related to the events of metastasis in both humans and animals. The basic and clinical related research covered in this topic represented many disciplines. The presentations showed novel findings and at the same time, raised many new unanswered questions, indicating the limited knowledge we still have regarding the molecular events of metastasis. The hope is that further unraveling of the direct and indirect molecular events of lymphatic metastasis will lead to new approaches in developing effective therapeutics.

Detection of occult tumor cells in lymph nodes from non-small cell lung cancer patients using reverse transcription-polymerase chain reaction for carcinoembryonic antigen mRNA with the evaluation of its sensitivity

We evaluated the usefulness of a real-time quantitative reverse transcription-polymerase chain reaction (RT-PCR) method for detecting occult tumor cells in histologically malignant-negative lymph nodes resected from patients with non-small cell lung cancer. First, we examined the relationship between tumor cell number and carcinoembryonic antigen (CEA) mRNA copy number using a PCR method with a cancer cell line (A549) in a serial dilution study. Next, we evaluated the relationship between nodal metastatic area size and CEA mRNA copy number using lymph nodes with histologically proven metastasis in a serial slice study. On the basis of those results, we performed RT-PCR analyses with 28 primary tumors and 211 lymph nodes from 28 patients who underwent a lobectomy with systematic node dissection. Our results in the serial dilution study showed that the detectable limitation by quantitative RT-PCR was 25-100 neoplastic cells and 20-100 CEA mRNA copy numbers. In the serial slice study, we found a correlation between CEA mRNA copy number and nodal metastatic area. In the clinical samples, amplification of CEA mRNA was obtained with all 28 primary tumors and 13 of the lymph nodes with metastasis shown by hematoxylin-eosin staining. Furthermore, 52 (25%) of 211 histologically negative lymph nodes and the specimens from 14 (64%) of the 22 pN0 patients revealed a significant level of CEA mRNA. These results indicate that micrometastases, which are not detectable with conventional examinations, can be detected by the present method of RT-PCR for CEA mRNA in a proportion of patients with resected pN0 non-small cell lung cancer.

Detection of disseminated lung cancer cells in regional lymph nodes by assay of CK19 reverse transcriptase polymerase chain reaction and its clinical significance

PURPOSE

To set up a molecular method (i.e. RT-PCR) that can be used to detect disseminated tumor cells (DTCs) in regional lymph nodes (LNs) in patients with lung cancer and to evaluate its clinical significance.

METHODS

Cytokeratin 19 (CK(19)) was used as marker. Serial dilution study for LC-5 cells (a lung squamous cell line) was performed to detect sensitivity of the molecular protocol. Regional LNs (n = 261) and primary lung cancer tissue (n = 40) were obtained from 40 patients with lung cancer who underwent lobectomy or pneumonectomy. They were randomly categorized into two groups: group I (LN-based study, n = 20) and group II (patient-based study, n = 20). Each LN was halved. One half of a LN was subjected to histological examination (HE) and the other half was subjected to RT-PCR amplification of CK(19) mRNA. The effect on survival was analyzed. The cumulative survival was calculated by the Kaplan-Meier method and compared by the log rank test. The Cox model analyzed the prognostic factors.

RESULTS

CK(19) mRNA expressed in all tumor tissues as well as LC-5, PAa cells (a lung adenocarcinoma cell line), but not in normal control LNs. Serial dilution study for LC-5 cells demonstrated that CK(19) mRNA was detectable at a concentration as low as 10 LC-5 cells in 1x10(7) LN cells. There was no significant difference between the detecting result of single LN and that of mixed LNs (P > 0.05). In 18 of 40 patients, the metastasis in regional LNs was found by both HE and RT-PCR. Of 22 patients without pathologically involved nodes, six (27%) were found to express CK(19) mRNA in regional LNs. According to the results of regional LNs in 40 patients by molecular assay, the presence of the CK(19) product in LNs was related to tumor size (chi(2) = 5.76, P < 0.025) as well as cell differentiation of the tumor (chi(2) = 7.08, P < 0.01). Following a median observation time of 26 months (range, 4 to 60 months), patients with DTCs in nodes showed significant shorter disease-free survival duration than node-negative patients (log-rank test, P = 0.001). The independence of this prognostic significance was demonstrated by a multivariate analysis (Cox regression model, P = 0.004). The results diagnosed by HE had no significant effect on prognoses (P = 0.455).

CONCLUSIONS

Comparing with HE, RT-PCR can make more accurate assessment of metastatic status in LNs, which is helpful for screening the patients in whom the early subclinical metastasis exists and disclosing the intrinsic regulation of malignant metastasis. The presence of DTCs in LNs is an independent factor for prognosis. Molecular detection of DTCs in LNs is a supplement for current tumor staging in lung carcinoma.