PRC2/EED-EZH2 Complex Is Up-Regulated in Breast Cancer Lymph Node Metastasis Compared to Primary Tumor and Correlates with Tumor Proliferation In Situ

Background

Lymph node metastasis is a key event in the progression of breast cancer. Therefore it is important to understand the underlying mechanisms which facilitate regional lymph node metastatic progression.

Methodology/Principal Findings

We performed gene expression profiling of purified tumor cells from human breast tumor and lymph node metastasis. By microarray network analysis, we found an increased expression of polycomb repression complex 2 (PRC2) core subunits EED and EZH2 in lymph node metastatic tumor cells over primary tumor cells which were validated through real-time PCR. Additionally, immunohistochemical (IHC) staining and quantitative image analysis of whole tissue sections showed a significant increase of EZH2 expressing tumor cells in lymph nodes over paired primary breast tumors, which strongly correlated with tumor cell proliferation in situ. We further explored the mechanisms of PRC2 gene up-regulation in metastatic tumor cells and found up-regulation of E2F genes, MYC targets and down-regulation of tumor suppressor gene E-cadherin targets in lymph node metastasis through GSEA analyses. Using IHC, the expression of potential EZH2 target, E-cadherin was examined in paired primary/lymph node samples and was found to be significantly decreased in lymph node metastases over paired primary tumors.

Conclusions/Significance

This study identified an over expression of the epigenetic silencing complex PRC2/EED-EZH2 in breast cancer lymph node metastasis as compared to primary tumor and its positive association with tumor cell proliferation in situ. Concurrently, PRC2 target protein E-cadherin was significant decreased in lymph node metastases, suggesting PRC2 promotes epithelial mesenchymal transition (EMT) in lymph node metastatic process through repression of E-cadherin. These results indicate that epigenetic regulation mediated by PRC2 proteins may provide additional advantage for the outgrowth of metastatic tumor cells in lymph nodes. This opens up epigenetic drug development possibilities for the treatment and prevention of lymph node metastasis in breast cancer.     

SPARC Is a Key Regulator of Proliferation, Apoptosis and Invasion in Human Ovarian Cancer

Background

Secreted protein acidic and rich in cysteine (SPARC), a calcium-binding matricellular glycoprotein, is implicated in the progression of many cancers. In this study, we investigated the expression and function of SPARC in ovarian cancer.

Methods

cDNA microarray analysis was performed to compare gene expression profiles of the highly invasive and the low invasive subclones derived from the SKOV3 human ovarian cancer cell line. Immunohistochemistry (IHC) staining was performed to investigate SPARC expression in a total of 140 ovarian tissue specimens. In functional assays, effects of SPARC knockdown on the biological behavior of ovarian cancer cells were investigated. The mechanisms of SPARC in ovarian cancer proliferation, apoptosis and invasion were also researched.

Results

SPARC was overexpressed in the highly invasive subclone compared with the low invasive subclone. High SPARC expression was associated with high stage, low differentiation, lymph node metastasis and poor prognosis of ovarian cancer. Knockdown of SPARC expression significantly suppressed ovarian cancer cell proliferation, induced cell apoptosis and inhibited cell invasion and metastasis.

Conclusion

SPARC is overexpressed in highly invasive subclone and ovarian cancer tissues and plays an important role in ovarian cancer growth, apoptosis and metastasis.     

FOXP3+ Lymphocyte Density in Pancreatic Cancer Correlates with Lymph Node Metastasis

Objective

To determine if the density of FOXP3⁺ lymphocytes in primary tumors and lymph nodes in pancreatic cancer correlates with the presence of lymph node metastases.

Methods

FOXP3⁺ lymphocyte density in primary pancreatic cancer tissue and draining lymph nodes was measured using immunohistochemistry. We analyzed the clinical and pathological aspects associated with the accumulation of FOXP3⁺ lymphocytes in pancreatic cancer. We also analyzed the correlation of density of FOXP3⁺ lymphocytes in lymph nodes with the nodal status and distance from the primary tumor.

Results

FOXP3⁺ lymphocyte density in pancreatic cancer was significantly higher than in paratumoral pancreatic tissue. The density of FOXP3⁺ lymphocytes in local tumor tissue correlated significantly with the histological grade and overall lymph node status. Furthermore, FOXP3⁺ lymphocyte density was significantly higher in positive lymph nodes than in negative ones, while it had no correlation with the distance of the lymph node from the primary tumor.

Conclusion

FOXP3⁺ lymphocyte density in primary tumor tissue in patients with pancreatic cancer correlates with lymph node metastasis. Lymph nodes containing metastases having higher FOXP3⁺ lymphocyte densities than do negative lymph nodes.     

胃癌组织中的MUC1和VEGF表达及其意义

目的:检测胃癌组织中VEGF和MUC1的表达情况,研究二者与胃癌生物学行为之间的关系。方法:应用免疫组织化学SP法检测VEGF和MUC1在胃癌组织和癌旁组织中的表达情况。结果:胃癌组织中VEGF的阳性表达明显高于癌旁组织,两者之间差异存在统计学意义(P0.05),VEGF在胃癌组织中的表达与胃癌浸润深度、有无远处转移、有无淋巴结转移、TNM分期有关,之间差异存在统计学意义(P0.05);胃癌组织中MUC1的阳性表达明显高于癌旁组织,两者之间差异存在统计学意义(P0.05),MUC1在胃癌组织中的表达与分化程度、TNM分期、淋巴结转移、远处转移有关,差异有统计学意义(P0.05);胃癌患者组织VEGF与MUC1的表达水平呈正相关(r=0.210,P0.05)。结论:VEGF和MUC1在胃癌发生、发展和转移过程中起重要作用,可能成为检测胃癌的重要肿瘤标志物。     

Evaluation of Tumor Cell Proliferation by Ki-67 Expression and Mitotic Count in Lymph Node Metastases from Breast Cancer

Few studies have addressed the risk of recurrence by assessing proliferation markers in lymph node metastasis from breast cancer. Here, we aimed to examine Ki-67 expression and mitotic count in lymph nodes in comparison with primary tumors. A cohort of node positive breast cancer (n = 168) was studied as a part of the prospective Norwegian Breast Cancer Screening Program (1996–2009). The percentage of Ki-67 positivity was counted per 500 tumor cells in hot-spot areas (x630). Mitotic count was conducted in the most cellular and mitotic active areas in 10 high power fields (x400). Our results showed that Ki-67 and mitotic count were significantly correlated between primary tumor and lymph nodes (Spearman`s correlation 0. 56 and 0.46, respectively) and were associated with most of the histologic features of the primary tumor. Univariate survival analysis (log-rank test) showed that high Ki-67 and mitotic count in the primary tumor and lymph node metastasis significantly predicted risk of recurrence. In multivariate analysis, mitotic count in the lymph node metastasis was an independent predictor of tumor recurrence. In conclusion, proliferation markers in lymph node metastases significantly predicted disease free survival in node positive breast cancer.     

Significance of Lymph Node Metastasis in Cancer Dissemination of Head and Neck Cancer

Lymph node metastasis (LNM) in many solid cancers is a well-known prognostic factor; however, it has been debated whether regional LNM simply reflects tumor aggressiveness or is a source for further tumor dissemination. Similarly, the metastatic process in head and neck cancer (HNC) has not been fully evaluated. Thus, we aimed to investigate the relative significance of LNM in metastatic cascade of HNC using functional imaging of HNC patients and molecular imaging in in vivo models. First, we analyzed ¹⁸Fluorodeoxyglucose positron emission tomography (PET) parameters of 117 patients with oral cancer. The primary tumor and nodal PET parameters were measured separately, and survival analyses were conducted on the basis of clinical and PET variables to identify significant prognostic factors. In multivariate analyses, we found that only the metastatic node PET values were significant. Next, we compared the relative frequency of lung metastasis in primary ear tumors versus lymph node (LN) tumors, and we tested the rate of lung metastasis in another animal model, in which each animal had both primary and LN tumors that were expressing different colors. As a result, LN tumors showed higher frequencies of lung metastasis compared to orthotopic primary tumors. In color-matched comparisons, the relative contribution to lung metastasis was higher in LN tumors than in primary tumors, although both primary and LN tumors caused lung metastases. In summary, tumors growing in the LN microenvironment spread to systemic sites more commonly than primary tumors in HNC, suggesting that the adequate management of LNM can reduce further systemic metastasis.     

MMP-7 is Upregulated by COX-2 and Promotes Proliferation and Invasion of Lung Adenocarcinoma Cells

Matrix metalloproteinases (MMPs) have been implicated in a variety of pathophysiological conditions, of which MMP-7 is expressed by tumor cells of epithelial and mesenchymal origin. However, the function of MMP-7 in human lung adenocarcinoma (LAC) is unclear. In the present study the expression of MMP-7 in LAC was examined by immunohistochemical assay using a tissue microarray procedure. A loss-of-function experiment was performed to explore the effects and molecular mechanisms of lentiviral vector-mediated MMP-7 siRNA (siMMP-7) on cell proliferation and invasive potential in LAC A549 cells, measured by MTT and Transwell assays, respectively. It was found that, the expression of MMP-7 protein in LAC was significantly increased compared with that in adjacent non-cancerous tissues (ANCT) (76.0% vs 44.0%, P<0.001), and positively correlated with lymph node metastases of the tumor (P=0.014). Furthermore, targeted inhibition of cyclooxygenase-2 (COX-2) by siRNA downregulated the expression of MMP-7 and inhibited invasion of LAC cells, and knockdown of MMP-7 suppressed tumor proliferation and invasion in LAC cells. Taken together, our findings indicate that increased expression of MMP-7 is associated with lymph node metastasis and upregulated by COX-2, and promotes the tumorigenesis of LAC, suggesting that MMP-7 may be a potential therapeutic target for the treatment of cancer.Key words: MMP-7, COX-2, lung adenocarcinoma     

RABEX-5 Is Upregulated and Plays an Oncogenic Role in Gastric Cancer Development by Activating the VEGF Signaling Pathway

RABEX-5, a guanine-nucleotide exchange factor (GEF) for RAB-5, is implicated in tumorigenesis and in the development of certain human cancers. Here, we report that RABEX-5 promotes tumor growth and the metastatic ability of gastric cancer cells both in vitro and in vivo. Expression of RABEX-5 is significantly higher in gastric cancer tissues and is associated with tumor size and lymph node metastasis. In addition, targeted silencing of RABEX-5 reduced gastric cancer cell proliferation and colony formation in vitro via the induction of a G0/G1 phase arrest, and stimulated gastric cancer cell apoptosis. Knockdown of RABEX-5 also inhibited wound healing, migration and the invasive abilities of gastric cancer cells. The results of in vivo animal experiments were also consistent with these in vitro findings. Silencing of RABEX-5 led to decreased expression of VEGF. These results indicate that RABEX-5 is upregulated and plays an oncogenic role in gastric cancer development by activating the VEGF signaling pathway.     

胃癌原发灶及淋巴结Her2 基因表达的差异性研究

目的:明确胃癌原发灶与其转移淋巴结中Her2过表达或扩增的差异性,为临床胃癌治疗方案的选择提供参考依据。方法:选择112例经术后病理检查证实为胃癌原发灶Her2强阳性(Her2阳性表达为3+)表达并伴有淋巴结转移的患者样本,应用免疫组化方法并参照《胃癌Her2检测指南》中规定的检测流程重新判定有Her2过表达或扩增的胃癌原发病灶其相应的转移淋巴结中Her2有无过表达或扩增,再将检测结果进行比较。结果:112例患者中,胃癌组织Her2的阳性率为74.11%,淋巴结Her2的阳性表达为66.07%,二者共同阳性表达率为61.61%,差异无统计学意义(P=0.064)。两,二者一致率为83.04%,kappa检验结果为(Z=6.452,P0.001)。胃癌组织Her2的基因表达与年龄、性别、肿瘤位置和肿瘤大小以及远端转移均无显著相关性,而与Lauren分型、组织学分级、浸润深度、淋巴结转移以及TNM分期有关(P0.05)。结论:胃癌原发病灶中Her2过表达或扩增与其相应的转移淋巴结中Her2过表达或扩增具有一致性。胃癌组织Her2状态与Lauren分型、组织学分级、浸润深度、淋巴结转移以及TNM分期有关。     

The Expression of TMPRSS4 and Erk1 Correlates with Metastasis and Poor Prognosis in Chinese Patients with Gastric Cancer

Purpose

The present study investigated the clinical significance of transmembrane protease, serine 4(TMPRSS4) and extracellular signal-regulated kinases 1 (Erk1) in the development, progression and metastasis of gastric cancer.

Methods

Immunohistochemistry was employed to analyze TMPRSS4 and Erk1 expression in 436 gastric cancer cases and 92 non-cancerous human gastric tissues.

Results

Protein levels of TMPRSS4 and Erk1 were up-regulated in gastric cancer lesions compared with adjacent noncancerous tissues. High expression of TMPRSS4 correlated with age, size, Lauren’s classification, depth of invasion, lymph node and distant metastases, regional lymph node stage and TNM stage, and also with expression of Erk1. In stages I, II and III, the 5-year survival rate of patients with high TMPRSS4 expression was significantly lower than in patients with low expression. Further multivariate analysis suggests that up-regulation of TMPRSS4 and Erk1 were independent prognostic indicators for the disease, along with depth of invasion, lymph node and distant metastasis and TNM stage.

Conclusions

Expression of TMPRSS4 in gastric cancer is significantly associated with lymph node and distant metastasis, high Erk1 expression, and poor prognosis. TMPRSS4 and Erk1 proteins could be useful markers to predict tumor progression and prognosis of gastric cancer.     

The correlation between pre-operative serum tumor markers and lymph node metastasis in gastric cancer patients undergoing curative treatment

Abstract

Background: There was few study concentrated on the correlation between the evaluated tumor markers and lymph node metastasis. In this study, we aimed to evaluate the correlation between the CA724, CA242, CA199, CEA and the lymph node metastasis of gastric cancer and assess the prognostic value of them in different N stage patients.

Methods: We analyzed the correlation between serum level of CA724, CA242, CA199, CEA and lymph node metastasis in 1501 gastric cancer patients.

Results: Lymph node metastasis of gastric cancer was related with tumor location, Bormann type, tumor size, histological type, depth of invasion and TNM stage (p?<?0.05). The values of CA724, CA242, CA199 and CEA were positively correlated with the metastatic lymph node counts and the N stage (p?<?0.05). The later the N stage was, the levels of CA724, CA242 and CA199 were higher. The later the N stage was, the positive rates of tumor markers were higher (p?<?0.05). In comparing with single tumor markers, the positive rates of tumor markers combination were higher. The combination of CA724?+?CA242?+?CA199?+?CEA had highest positive rate. The higher CEA level related to N1 stage patients while higher CA199 was related with poor prognosis for N1 stage patients. For N0 and N2 stage patients, evaluation of CA724 indicated poorer prognosis. For N1 and N2 stage gastric patients, the patients with increased CA242 inclined to have shorter survival time.

Conclusions: The tumor makers CA724, CA242, CA199 and CEA were evaluated significantly in the gastric patients with later N stage. The combination of these four tumor markers maybe prefer diagnostic index of gastric cancer and its lymph node metastasis. These tumor markers can be a possible indicator of poorer prognosis in different N stage patients.     

The Expression and Prognostic Significance of VEGF and CXCR4 in Gastric Cancer: Correlation with Angiogenesis,Lymphangiogenesis and Progression

The cellular response to hypoxia includes the expression of hypoxia-inducible factor-1 (HIF-1) and its target genes: vascular endothelial growth factor (VEGF) and CXC chemokine receptor 4 (CXCR4). The aim of this study was to investigate the expression and prognostic significance of VEGF and CXCR4, which are responsible for angiogenesis and progression in gastric cancer. Twenty-eight gastric cancer patients were analyzed. The mRNA expression was examined in primary tumors and corresponding normal gastric mucosa by RT-PCR. The protein level was examined by immunohistochemistry staining. The high expression of VEGF and CXCR4 was found in 71.0 and 64.0% of tumors, respectively. The mean levels of VEGF and CXCR4 were upregulated in primary tumors compared to normal mucosa (p = 0.0007, p = 0.0052). A correlation between VEGF expression and tumor invasion (p = 0.0216) and stage (p = 0.0181) was found. CXCR4 expression correlated with lymph node metastases (p = 0.0237) and stage (p = 0.0054). The VEGF expression correlated with microvessel density (MVD) (p = 0.0491). The overall 3-year survival rate was 46.4% and correlated negatively with high CXCR4 mRNA expression (p = 0.0089). VEGF and CXCR4 play an important role in tumor progression. Their overexpression correlates with a bad prognosis and may improve high-risk patient selection, and these patients may obtain additional survival benefits if treated more aggressively.     

Detection and Characterization of Metastatic Cancer Cells in the Mesogastrium of Gastric Cancer Patients

Gastric cancer is the second leading cause of cancer death worldwide. Here, we propose a novel type of tumor metastasis designated as Metastasis V in gastric cancer. Metastasis V is defined as the appearance of cancer cells in the mesogastrium with perigastric adipose tissue. To detect its incidence and characterize its clinic pathological features, large cross sectional tissue analysis of mesogastrium from 74 patients were used. Metastasis V was detected in 1 of 40 (2.5%) patients with early gastric cancer, 8 of 34 (24%) patients with advanced gastric cancer. The mean distance of Metastasis V from gastric wall was approximately 2.6 cm. Metastasis V was closely associated with tumor invasion depth, along with a number of positive lymph node metastasis. The prognosis of patients with Metastasis V was significantly (P<0.05) worse than those with tumor cell-free mesogastrium. These findings indicate that by using whole-sectional analysis, Metastasis V can be detected in the mesogastrium of gastric cancer patients, and also suggests that it may be a risk factor for patient survival after radical surgery.     

Tumor-targeting amino acid auxotrophic <Emphasis Type="Italic">Salmonella typhimurium</Emphasis>

We have developed an effective bacterial cancer therapy strategy by targeting viable tumor tissue using Salmonella typhimurium auxotrophs that we have generated which grow in viable as well as necrotic areas of tumors. However, the auxotrophy severely restricts growth of these bacteria in normal tissue. The S. typhimurium A1-R mutant, which is auxotrophic for leu-arg and has high anti-tumor virulence, was developed in our laboratory. In vitro, A1-R infects tumor cells and causes nuclear destruction. A1-R was initially used to treat metastatic human prostate and breast tumors that had been orthotopically implanted in nude mice. Forty percent of treated mice were cured completely and survived as long as non-tumor-bearing mice. A1-R administered i.v. to nude mice with primary osteosarcoma and lung metastasis was highly effective, especially against metastasis. A1-R was also targeted to both axillary lymph and popliteal lymph node metastasis of human pancreatic cancer and fibrosarcoma, respectively, as well as lung metastasis of the fibrosarcoma in nude mice. The bacteria were delivered via a lymphatic channel to target the lymph node metastases and systemically via the tail vein to target the lung metastasis. The metastases were cured without the need of chemotherapy or any other treatment. A1-R was administered intratumorally to nude mice with an orthotopically transplanted human pancreatic tumor. The primary pancreatic cancer regressed without additional chemotherapy or any other treatment. A1-R was also effective against pancreatic cancer liver metastasis when administered intrasplenically to nude mice. The approach described here, where bacterial monotherapy effectively treats primary and metastatic tumors, is a significant improvement over previous bacterial tumor-therapy strategies that require combination with toxic chemotherapy. Three promoter clones engineered in S. enterica typhimurium were identified to have enhanced expression in bacteria growing in tumors relative to those growing in the spleen. The expression of therapeutics in Salmonella under the regulation of one or more promoters that are activated preferentially in tumors has the potential to improve the efficacy of Salmonella tumor therapy. Exploitation of the tumor-killing capability of Salmonella has great promise for a new paradigm of cancer therapy.     

Analysis of Lymph Node Metastasis Correlation with Prognosis in Patients with T2 Gastric Cancer

Purpose

To investigate the correlated factors for lymph node metastasis and prognosis for patients with T2 gastric cancer.

Methods

A total of 442 patients with T2 gastric cancer who underwent gastrectomy from January 1996 to December 2009 were evaluated. The clinicopathological parameters were analyzed for lymph node metastasis and prognosis, including gender, age, tumor size, tumor location, histological type, depth of invasion, vascular tumor emboli, nervous invasion, resection type, and pathological stage.

Results

The rate of lymph node metastasis was 45.9%. Univariate analysis showed that depth of invasion, tumor size, and vascular tumor emboli were associated with lymph node metastasis. Logistic regression demonstrated that depth of invasion, tumor size, and vascular tumor emboli were independently predictive factors for lymph node metastasis. The 5-year survival rate was 64.0%. Multivariate analysis showed that tumor size, tumor location, resection type, and pathological stage were independent prognostic factors. Based on tumor size, there were significant differences of 5-year survival between small size tumor (<6 cm) and large size tumor (≥6 cm) according to stage IIA (P = 0.006). Based on tumor location, there were significant differences of 5-year survival among different tumor location according to stage IB. Based on resection type, there were significant differences of overall 5-year survival between curative surgery and palliative surgery according to stage IIB (P = 0.015) and IIIA (P = 0.001).

Conclusion

Depth of invasion, tumor size, and vascular tumor emboli were independently predictive factors for lymph node metastasis. Tumor size, tumor location, resection type, and pathological stage were independent prognostic factors.     

VEGF-C 和VEGFR-3 在胃癌组织中的表达及临床意义

目的:探讨胃癌患者血管内皮生长因子C(vascular endothelial growth factor-C,VEGF-C及血管内皮生长因子受体-3(vascular endothelial growth factor receptor-3,VEGFR-3)在胃癌组织中的表达,从而确定胃癌预后的分子标志物。方法:搜集整理临床资料,采用Real-time PCR及ELISA法检测43例胃癌组织VEGF-C和VEGFR-3的表达。结果:43例胃癌组织中均有不同程度的VEGF-C和VEGFR-3的表达,Real-time PCR结果显示胃癌组织淋巴结转移组和非转移组VEGF-C和VEGFR-3的表达分别为0.07±0.01和0.12±0.01,0.03±0.01和0.06±0.02,与正常对照组相比,差异有显著性(p<0.05)。ELISA检测显示,与正常胃组织中VEGF-C和VEGFR-3的蛋白表达相比,胃癌无淋巴结转移组及胃癌并发淋巴结转移组中VEGF-C和VEGFR-3均明显增加。结论:VEGF-C和VEGFR-3的表达与胃癌淋巴结转移密切相关,提示胃癌标本VEGF-C和VEGFR-3的检测可作为胃癌预后的分子标志物。     

Expression of FHL1 in gastric cancer tissue and its correlation with the invasion and metastasis of gastric cancer

This study was performed to analyze the expression of four and a half LIM domains 1 (FHL1) in gastric carcinoma tissue and its correlation with the clinicopathological characteristics of gastric cancer. In addition, the role of FHL1 in the invasion and metastasis of gastric cancer cells was investigated to provide an experimental basis for future treatments of gastric cancer. FHL1 mRNA and protein expression in gastric carcinoma and the adjacent normal gastric mucosa tissue were determined using RT-PCR and western blots. Correlations of FHL1 expression with the incidence, progression, and clinicopathological characteristics of gastric cancer were analyzed. Changes in the invasion and metastatic potential of MKN45 human gastric cancer cells were observed after the transient transfection with an eukaryotic expression vector containing full-length FHL1. Expression of FHL1 mRNA in gastric carcinoma tissue was significantly lower than that in the adjacent normal tissue (P < 0.05). FHL1 expression in gastric carcinoma tissue from patients who were positive for lymph node metastasis was significantly lower than those in patients who were negative for lymph node metastasis (P < 0.05). Lower FHL1 expression was correlated with lower degrees of differentiation, higher TNM stages, and greater invasive potential of the gastric cancer (P < 0.05). The FHL1 mRNA and protein expression patterns were similar in gastric cancer. FHL1 protein expression in gastric carcinoma tissue was significantly lower than that in the surrounding normal tissue (P < 0.05). FHL1 protein expression was significantly lower in gastric carcinoma tissue from patients who were positive for lymph node metastasis than that detected in patients with no lymph node metastasis (P < 0.05). Lower FHL1 protein expression was correlated with lower degrees of differentiation, higher TNM stages, and greater invasive potential in gastric cancer (P < 0.05). However, the expression of FHL1 was independent of the patient's gender, age, and tumor size (P > 0.05). Overexpression of FHL1 in the MKN45 human gastric cancer cell line using an eukaryotic expression vector resulted in a significant reduction in the invasiveness and metastatic ability of these cells as determined using the Transwell chamber invasion assay (P < 0.05). The decrease in or loss of FHL1 expression may be related to the incidence, progression, invasiveness, and metastatic potential of gastric cancer.     

Ratio between Negative and Positive Lymph Nodes Is Suitable for Evaluation the Prognosis of Gastric Cancer Patients with Positive Node Metastasis

Objective

To date, there is no consensus to evaluate the most appropriate category of the nodal metastasis for precise predication the prognosis of gastric cancer patients with positive node metastasis after curative surgery.

Methods

We retrospectively analyzed the clinicopathologic characteristics and overall survival (OS) of 299 gastric cancer patients with positive node metastasis after curative surgery for evaluation the optimal category of the nodal metastasis.

Results

With the univariate and multivariate survival analyses, the depth of primary tumor invasion was identified as the independent predicators with the OS of 299 gastric cancer patients with nodal metastasis postoperatively, as were the number of positive lymph nodes (PLNs), the number of negative lymph nodes (NLNs), and the ratio between negative and positive lymph nodes (RNPL). The RNPL was identified to be more suitable for predication the OS of gastric cancer patients with positive node metastasis than the ratio between positive and dissected lymph nodes (RPDL) by using the stratum procedure of survival analysis. Besides, we found both PLNs and NLNs were independently correlated with OS of gastric cancer patients with nodal metastasis when RNPL, instead of RPDL, was controlled in the partial correlation model.

Conclusions

RNPL, a new category of the nodal metastasis, was suitable for predication the OS of gastric cancer patients with nodal metastasis after curative resection, as were the PLNs, and NLNs.