Clinical impact of intratumoral natural killer cell and dendritic cell infiltration in gastric cancer

Intratumoral natural killer cells (NKC) and dendritic cells (DC) may affect the clinical features of various gastrointestinal cancers. However, the relationship between intratumoral NKC and DC remains unclear. We examined 169 patients with gastric cancer who underwent gastrectomy at Kagoshima University Hospital. Immunohistochemical staining of CD57 and S-100-protein was performed to evaluate NKC and DC infiltration, respectively. A total of 25 areas containing pericancerous tissue were selected for determining the number of NKC and DC under high power microscopy (x400). Patients were classified into two groups according to NKC and DC population. Intratumoral lymphocytic infiltration was also calculated in 15 areas with a high power (x400) objective. The degree of NKC and DC infiltration was gradually decreased according to the progression of nodal involvement. Patients with many NKC infiltration had a lower positivity of lymph node metastasis and lymphatic invasion than patients with little NKC infiltration. DC infiltration was also negatively correlated with depth of invasion, lymph node metastasis and curativity. DC infiltration was positively correlated with lymphocytic infiltration (P=0.01. r=0.6). The 5-year survival rates of patients with many NKC infiltration and patients with DC many infiltration were 75 and 78%, respectively, both of which were significantly better than that of patients with little NKC and DC infiltration (P<0.05). NKC may be activated without DC or intratumoral lymphocytes. Intratumoral NKC may act as an independent immunologic effector against tumor cells, unlike DC.

Detection and prediction of micrometastasis in the lymph nodes of patients with pN0 gastric cancer

BACKGROUND

The clinicopathologic significance of micrometastasis (MM) and tumor cell microinvolvement (TCM) in regional lymph nodes as identified by immunohistochemical staining for cytokeratin expression was evaluated in patients with node-negative gastric cancer.

METHODS

MM was defined as tumor cells with stromal reaction, and TCM was defined as individual tumor cells without stromal reaction. We investigated 1761 lymph nodes obtained from 67 gastric cancer patients whose diagnosis showed no lymph node metastasis by routine histological examination. The depth of tumor invasion was T1 (submucosa) in 33 patients and T2 (muscularis propria and subserosa) in 34 patients. The lymph nodes were examined immunohistochemically for the presence of tumor cells using anti-cytokeratin AE1/AE3 monoclonal antibody. Both the biopsy tumor specimens obtained prior to surgery and the resected primary tumors were immunostained with E-cadherin (E-cad) monoclonal antibody.

RESULTS

Thirty (1.5%) of the 1761 lymph nodes showed MM and/or TCM. MM with or without TCM was found in 10 patients, and TCM alone was found in 4 patients; 6 (18.2%) of the 33 patients with T1 tumor and 8 (23.5%) of the 34 patients with T2 tumor had occult lymph node metastasis. The 5-year survival rate was worse among those with MM with or without TCM, than among those without MM. Nearly all of the patients with MM and/or TCM had reduced or negative E-cad expression in the primary tumor.

CONCLUSIONS

We demonstrated that the incidence of MM and/or TCM in the lymph nodes of patients with gastric cancer is quite high, and that such metastasis is associated with the prognosis of patients with pN0. Examination of E-cad expression in biopsy tumor specimens may be useful for predicting MM and/or TCM.

Clinical importance of preoperative carcinoembryonic antigen and carbohydrate antigen 19-9 levels in gastric cancer

Although serum carcinoembryonic antigen (CEA) and carbohydrate antigen (CA) 19-9 are commonly measured before surgery for gastric carcinoma, this clinical significance is not fully understood. We evaluated a total of 549 patients with gastric cancer who underwent gastrectomy. Levels of CEA and CA19-9 were measured preoperatively in all patients. We retrospectively analyzed correlations between CEA or CA19-9 and clinicopathologic features, and estimated the prognostic utility of the tumor markers by analyzing clinicopathologic characteristics of the carcinoma as a function of seropositivity or negativity of the antigens in combination or by raising the levels. The positivity rates of CEA (> or =5 ng/mL) and CA19-9 (> or =37 U/mL) were 19.5% and 18%, respectively. Serum CEA and CA19-9 positivity significantly correlated with depth of invasion, hepatic metastasis, and curativity. Forty-nine patients positive for both CEA and CA19-9 had significantly higher frequencies of lymph node metastasis, deeper invasion by the tumor, lower rates of curative resection (p < 0.01), and higher rates of hepatic metastasis (p < 0.05) than 377 patients with normal levels of CEA and CA19-9. Surgical outcomes of patients who were CEA- and CA19-9-positive were poorer than those of patients with normal CEA and CA19-9 levels (p < 0.01). Significant correlation was found between serum CEA and CA19-9 level (p < 0.001, r = 0.24). Doubling the threshold level of serum positivity to 10 ng/mL (CEA) and 74 U/mL (CA19-9) improved the prognostic value of these factors. However, multivariate analysis using Cox's hazards model revealed that only CEA positivity using the doubled threshold value (10 ng/mL) (p = 0.04, hazard ratio = 1.7), nodal involvement (p = 0.01, hazard ratio = 1.9), and depth of invasion (p = 0.02 hazard ratio = 1.5) significantly predicted prognosis. Carcinoembryonic antigen positivity using the doubled threshold level (10 ng/mL) was an important prognostic factor in patients with gastric cancer.

Clinical significance of circulating tumor cells in peripheral blood from patients with gastric cancer

BACKGROUND

The authors hypothesized that circulating tumor cells (CTCs) in patients with gastric cancer are associated with prognosis and disease recurrence. In this study, they evaluated CTCs in gastric cancer and clarified the clinical impact of CTCs.

METHODS

In total, 265 consecutive patients with gastric cancer were enrolled. Fourteen patients were excluded from the analysis, including 12 patients who another cancer and 2 patients who refused the treatment. The remaining 251 patients were divided into 2 groups: 148 patients who underwent gastrectomy (the resection group) and 103 patients who did not undergo gastrectomy (the nonresectable group). Peripheral blood samples were collected before gastrectomy or chemotherapy. A proprietary test for capturing, identifying, and counting CTCs in blood was used for the isolation and enumeration of CTCs.

RESULTS

CTCs were detected in 16 patients (10.8%) from the resection group and in 62 patients (60.2%) from the nonresectable group. The overall survival rate for the entire cohort was significantly lower in patients with CTCs than in those without CTCs (P < .0001). In the resection group, relapse-free and overall survival in patients with CTCs was significantly lower than in patients without CTCs (P < .0001). It was noteworthy that the expression of CTCs was an independent factor for determining the overall survival of patients with gastric cancer in multivariate analysis (P = .024). In the nonresectable group, the overall survival rate was significantly lower in patients with CTCs than in those without CTCs (P = .0044).

CONCLUSIONS

The evaluation of CTCs in peripheral blood may be a useful tool for predicting tumor progression, prognosis, and the effect of chemotherapy in patients with gastric cancer.

The effect of dexamethasone on defective nephrin transport caused by ER stress: a potential mechanism for the therapeutic action of glucocorticoids in the acquired glomerular diseases

The mechanism by which glucocorticoids govern antiproteinuric effect in nephrotic syndrome remains unknown. Present study examined the protective role of dexamethasone (DEX) in the intracellular trafficking of nephrin under endoplasmic reticulum (ER) stress. Human embryonic kidney-293 cell line expressing a full-length human nephrin was cultured in mediums containing 5.5 or 25 mM glucose with or without DEX. The result revealed that glucose starvation evoked a rapid ER stress leading to formation of underglycosylated nephrin that was remained in the ER as a complex with calreticulin/calnexin. DEX rescued this interfered trafficking through binding to its receptor and stimulating the mitochondrial transcripts and adenosine 5' triphosphate (ATP) production, leading to synthesis of fully glycosylated nephrin. These results suggest that ER-stress in podocytes may cause alteration of nephrin N-glycosylation, which may be an underlying factor in the pathomechanism of the proteinuria in nephrotic syndrome. DEX may restore this imbalance by stimulating expression of mitochondrial genes, resulted in the production of ATP that is essential factor for proper folding machinery aided by the ER chaperones.

Clinicopathological significance of nuclear factor (erythroid-2)-related factor 2 (Nrf2) expression in gastric cancer

Background

The transcription factor nuclear factor (erythroid-2)–related factor 2 (Nrf2) was originally identified as a critical regulator of intracellular anti-oxidants and of phase II detoxification enzymes through its transcriptional up-regulation of many anti-oxidant response element (ARE)-containing genes. Nrf2 protects not only normal cells but also cancer cells from cellular stress, and enhances cancer cell survival. Some studies have shown that Nrf2 expression in cancer patients has clinical significance. However, there has been no comprehensive analysis of the nuclear expression level of Nrf2 in gastrointestinal cancer cells. In this study we aimed to immunohistochemically evaluate the expression of Nrf2, and to assess its clinical significance in gastric cancer.

Methods

A total of 175 gastric cancer patients who received R0 gastrectomy with standard lymph node dissection were enrolled. We immunohistochemically evaluated Nrf2 expression in the paraffin-embedded surgically resected specimens of these 175 patients. Group differences were analyzed using the χ² test, Fisher’s exact test, and the Mann–Whitney U test. Associations between Nrf2 expression and clinicopathological features, including clinical outcome, were assessed using univariate and multivariate analyses, and Kaplan-Meier curves with the log-rank test, respectively.

Results

Nrf2 immunoreactivity was predominantly identified in the nucleus of gastric cancer cells. Nrf2 positivity was closely associated with tumor size, tumor depth, lymph node metastases, lymphovascular invasion, histology and stage (p < 0.05 for all). A log-rank test indicated that the overall survival of the Nrf2-positive group was significantly poorer than that of the Nrf2-negative group (p < 0.01). And, positive Nrf2 expression was significantly associated with resistance to 5FU-based adjuvant chemotherapy (p = 0.024).

Conclusions

Nrf2 expression was positively associated with aggressive tumor behavior in gastric cancer. This result suggests that Nrf2 expression in gastric cancer is a potential indicator of worse prognosis.

Invariant chain expression in gastric cancer

Invariant chain (Ii) is a chaperone molecule that inhibits the binding of endogenous antigens to HLA class II. The tumor cell with overexpressed Ii chain is thought to escape attacking cytotoxic lymphocytes by suppressing the host immune. However, the relationship between Ii expression by the tumor and clinicopathological factors in gastric cancer remains unclear. We studied 126 patients with gastric cancer who had undergone curative gastrectomy at Kagoshima University Hospital between 1988 and 1997. In order to detect Ii and HLA-DR expression by tumor cells, immunohistochemical staining with anti-CD74 and anti-HLA-DR antibodies were performed by avidin-biotin peroxidase complex method. The 126 patients studied were divided into two groups based on Ii expression. Ii and HLA-DR were expressed both on the surface and in the cytoplasm of tumor cells and tumor infiltrating lymphocytes. A total of 48 patients were identified as Ii positive, while the remaining 78 patients were Ii negative. Ii expression negatively correlated with the depth of invasion of the tumor as well as the patients' clinical stage. Ii expression was negatively correlated with HLA-DR expression. Patients with Ii negative expression had significantly better surgical outcomes than those with Ii positive expression (P<0.05). Ii expression in gastric cancer affected surgical outcome and Ii expression was negatively correlated with depth of invasion and HLA-DR expression. Ii expression in gastric cancer may be a prognostic factor related to suppressive effects on host immune responses to tumor cells.

Clinical significance of circulating tumor cells in blood by molecular detection and tumor markers in esophageal cancer

BACKGROUND

The clinical significance of circulating tumor cells in the blood during surgery has not been elucidated in esophageal squamous cell carcinoma (ESCC). We evaluated the relationship between circulating tumor cells and clinicopathologic findings, compared with that of serum squamous cell carcinoma (SCC) antigen and carcinoembryonic antigen (CEA), in ESCC.

METHODS

Blood samples from 54 consecutive patients were obtained from the peripheral artery and the superior vena cava at three points in time: immediately before surgery, and before and after tumor resection. CEA-specific reverse transcriptase-polymerase chain reaction (RT-PCR), which can quantify circulating tumor cells in blood, was performed. The preoperative values of serum SCC antigen and CEA were also obtained for all patients.

RESULTS

CEA messenger RNA (CEA mRNA) was detected in the blood of 31 out of 54 patients (57.4%). CEA mRNA positivity was detected most frequently after tumor resection and correlated with nodal status and stage grouping. The incidence of total recurrence and blood-borne recurrence was significantly greater in patients with CEA mRNA positivity than in those with CEA mRNA negativity (P =.036 and.0026, respectively). Preoperative serum levels of SCC antigen and CEA did not correlate with clinicopathologic findings and tumor recurrence.

CONCLUSIONS

CEA mRNA detected by RT-PCR was more predictive of tumor recurrence than serum tumor markers. Effective adjuvant therapy is recommended for patients with CEA mRNA positive expression.

Clinical significance of lymph node micrometastasis in gastric cancer

Recently, the existence of lymph node micrometastasis (LNM), including isolated tumor cells, has been focused on during the development of molecular diagnostic tools for lymph node metastasis in various malignant neoplasms. In particular, immunohistochemistry and reverse transcription-polymerase chain reaction have been reported to be available for the detection of LNM in gastric cancer. However, at present, the clinical significance of LNM remains unclear in patients with gastric cancer. Therefore, we cannot strategically make light of this issue in clinical management. Currently, minimally invasive treatments, such as endoscopic submucosal dissection and laparoscopic surgery with personalized lymphadenectomy, are widely performed in consideration of postsurgical quality of life (QOL). However, it is important to maintain the balance between QOL and curability when selecting surgical treatments for patients with gastric cancer. If minimally invasive surgery based on LNM status was established for patients with early gastric cancer, it could be performed safely. We reviewed the clinical significance of LNM as an important strategic target in patients with gastric cancer.

Intraoperative molecular detection of circulating tumor cells by reverse transcription-polymerase chain reaction in patients with biliary-pancreatic cancer is associated with hematogenous metastasis

BACKGROUND

Circulating tumor cells in the blood were frequently detected by reverse transcription-polymerase chain reaction during operation in patients with biliary-pancreatic cancer. We investigated the relationship between circulating tumor cells during operation and hematogenous metastases.

METHODS

Blood samples from 67 patients with biliary-pancreatic cancer were obtained from the portal vein, peripheral artery, and superior vena cava during operation. After total RNA was extracted from each blood sample, carcinoembryonic antigen (CEA)-specific reverse transcription-polymerase chain reaction was performed.

RESULTS

Intraoperative CEA-messenger RNA (mRNA) expression was detected in the blood of 32 (47.8%) of 67 patients with biliary-pancreatic cancer, although it was not detected in the blood obtained from 20 healthy volunteers or 15 patients with benign disease of the biliary pancreas. The incidence (37.5%) of hematogenous metastases after surgery in the CEA-mRNA-positive group (n = 32) was significantly higher than that (11.4%) in the negative group (n = 35; P =.01). In stage I, II, and III patients, survival of the CEA-mRNA-positive group was significantly worse compared with that of negative group (P =.03).

CONCLUSIONS

Intraoperative molecular detection of circulating tumor cells in patients with biliary-pancreatic cancer relates to a high risk of hematogenous metastasis and is associated with unfavorable prognosis even after curative resection.

Laparoscopic complete mesocolic excision with radical lymph node dissection along the surgical trunk for right colon cancer

BACKGROUND

We have evaluated the safety and feasibility of combining median-to-lateral and anterior-to-median (MLAM) approaches to perform laparoscopic complete mesocolic excision (CME) with radical lymph node dissection along the gastrocolic trunk of Henle (GTH) for right hemicolon cancer.

PATIENTS AND METHODS

We retrospectively analyzed data obtained from a prospectively maintained database on 31 consecutive patients who had undergone laparoscopic CME with radical lymph node dissection for right hemicolon cancer between January 2010 and December 2013. We used video recordings of the procedure to assess the quality of the surgery and completeness of CME. We also assessed operative data, pathological findings, length of large bowel resected, complications, BMI, operative time by experience of surgeon, and length of hospital stay.

RESULTS

All patients had undergone en bloc resection of the enveloped parietal planes and radical lymph node dissection along the surgical trunk without any serious intraoperative complications. Twenty six and five patients graded mesocolic and intra-mesocolic plane, respectively. Five, three, eleven, and thirteen patients had T1, T2, T3, and T4 tumors, respectively. The median number of lymph nodes retrieved was 25, lymph node metastasis being identified in 11 patients. The mean length of large bowel resected was 21.8 cm. The mean operative time and intraoperative blood loss were 269 min and 39 mL, respectively. No intraoperative complications occurred in any patient. Three patients had postoperative complications. The mean BMI was 22.6 kg/m(2). The mean operative time for patients stratified by BMI of <22 or ≥22 was 225 and 297 min, respectively. There were no correlations with operative time by experience of surgeon. The median postoperative hospital stay was 13 days.

CONCLUSIONS

Laparoscopic CME conducted by fusion fascia exposure with radical lymph node dissection along the GTH via a combination of MLAM approaches is a safe and feasible procedure for right hemicolon cancer.

Lymph node micrometastasis and lymphatic mapping determined by reverse transcriptase-polymerase chain reaction in pN0 gastric carcinoma

BACKGROUND

The purposes of this study were to examine lymph node micrometastasis (LMM) by reverse transcriptase-polymerase chain reaction (RT-PCR) method, and clarify the initial nodes involved by metastatic disease according to tumor location.

METHODS

We examined 312 lymph nodes obtained from 50 patients with node-negative gastric carcinoma. RT-PCR and immunohistochemistry were performed. The clinical characteristics of LMM were investigated, and the map of LMM was made according to tumor location.

RESULTS

The number of patients and LMM detected by RT-PCR was 14 and 17 and by immunohistochemistry was 7 and 8, respectively. RT-PCR was a more sensitive method than immunohistochemistry. LMM by RT-PCR correlated with depth of tumor invasion and lymphatic invasion. Regarding pT1 tumor, 9 patients with LMM had tumors that were of the macroscopically depressed type and 2 cm or more in diameter. According to the lymphatic map, right pericardial lymph nodes and lymph nodes along the lesser curvature were the initial nodes involved in the upper third of the stomach. Right pericardial lymph nodes, lymph nodes along the lesser curvature, and infrapyloric nodes were more important initial metastatic sites in the middle third of the stomach, and lymph nodes along the lesser curvature and infrapyloric nodes in the lower third.

CONCLUSIONS

We demonstrated the relationship between LMM and clinicopathologic factors, especially in pT1 tumor. The mapping of LMM may prove useful for selecting the optimal treatment.

Clinical implication of CXCL12 expression in gastric cancer

PURPOSE

Recent research has revealed that tumor cells expressing chemokine receptors have a crucial impact on patient survival. However, there is no information regarding chemokine expression in gastro-intestinal cancer. This study immunohistochemically investigated CXCL12 expression in gastric cancer and evaluated its association with clinical factors, including patient prognosis.

METHOD

A total of 185 gastric cancer patients receiving curative gastrectomy were assessed. CXCL12 expression was evaluated by immunohistochemical analysis. Tumors with CXCL12-positive cancer cells were regarded as CXCL12 positive, and according to the degree of CXCL12 expression, patients were divided into three groups (weak, 31 cases; moderate, 27 cases; strong, 20 cases). Correlations between CXCL12 expression and clinical factors in gastric cancer were then determined.

RESULTS

CXCL12 was found in the cellular membrane of cancer cells. Seventy-four of 185 patients were classified into the CXCL12-positive group. Patients were divided into three groups according to the positivity of CXCL12 expression. Significant associations between CXCL12 and lymph node metastases (p < 0.05), depth of invasion (p < 0.01), lymphatic invasion (p < 0.01), tumor diameter (p < 0.05), and clinical stage (p < 0.01) were seen. Univariate analysis revealed that the CXCL12-positive group had significantly poorer surgical outcome than the CXCL12-negative group (p < 0.01). Multivariate analysis revealed CXCL12 to be an independent prognostic factor in gastric cancer (p = 0.02).

CONCLUSION

Cancerous CXCL12 positivity was determined to be an independent prognostic factor in gastric cancer, with CXCL12-positive gastric cancer showing more-aggressive behavior. Autocrine CXCL12 secretion from tumor cells may activate CXCR-4 on the tumor cells, which may be related to of the viability of distant metastases.

Detection of micrometastases in sentinel node navigation surgery for gastric cancer

Although lymph node metastasis is one of the important prognostic factors for patients with gastric cancer, the clinical significance of micrometastasis remains controversial. In the 6th edition of the TMN classification, micrometastases were classified as micrometastasis (MM) and isolated tumor cells (ITC) according to its greatest dimension. The accurate diagnosis of micrometastases is required when considering less invasive surgery, especially in early stage of gastric cancer. Since generating useful information about micrometastases by conventional RT-PCR is time-consuming, this procedure is not useful for rapid diagnosis during surgery. Recently some new methods of genetic diagnosis have reduced the amount of time required to obtain information about micrometastases in lymph nodes to 30-40 min. Such methodology can be clinically applied during less invasive surgery. The sentinel node (SN) concept has recently been applied to gastric cancer and SN navigation surgery (SNNS) is ideal for reduction of lymphadenectomy in patients with early gastric cancer. However, we should think about some conditions to establish SN concept for gastric cancer: the particle size of radioisotope, relationship between metastatic area and RI uptake, and the diagnosis of micrometastases by various method such as histological examination, immunostaining and RT-PCR. Here, we described the current status of MM and ITC in the lymph nodes and the SN concept in gastric cancer.

CD3-zetachain expression of intratumoral lymphocytes is closely related to survival in gastric carcinoma patients

BACKGROUND

Impaired or reduced CD3 zeta chain (CD3-zeta) expression in T cells has been identified in various cancers and may be associated with an ineffective immune response. The clinical significance of CD3-zeta chain expression in tumor-infiltrating lymphocytes (TILs) in gastric carcinoma remains unclear.

METHODS

The authors immunohistochemically investigated CD3-zeta expression in TILs in 185 patients who had undergone curative gastrectomy. CD3-zeta/CD3 epsilon (CD3-epsilon) ratios were calculated. Patients were divided into two groups: a normal CD3-zeta group (n = 121) and a reduced CD3-zeta group (n = 64). Patients with a zeta per epsilon ratio of greater than 66% were placed in the normal CD3-zeta group.

RESULTS

Patients in the normal CD3-zeta group had fewer lymph node metastasis (P < 0.01) and a shallower depth of invasion (P < 0.05) than those in the reduced CD3-zeta group. The 5-year survival rate was 72% in the normal CD3-zeta group, which was significantly better than that in the reduced CD3-zeta group (55%; P < 0.01). When stratified according to clinical stage, the prognostic value was significantly different only in Stage IV patients. Multivariate analysis showed that CD3-zeta expression was an independent prognostic factor (P = 0.03) next to depth of invasion and lymph node involvement.

CONCLUSIONS

Reduced CD3-zeta expression in TILs was strongly correlated with progressive disease in gastric carcinomas. CD3-zeta expression in TILs is considered an immunologic, independent prognostic marker in gastric carcinoma patients. CD3-zeta normalization with cytokine treatment may lead to prolonged survival in advanced gastric carcinoma patients.

Clinical significance of stanniocalcin 2 expression as a predictor of tumor progression in gastric cancer

Stanniocalcin 2 (STC2) is a glycoprotein hormone that plays an important role in calcium and phosphate homeostasis. Furthermore, recent studies have demonstrated that STC2 expression in the primary site is correlated with tumor progression in several types of malignancies. However, few reports have investigated the clinical significance of STC2 expression in the blood of patients with gastric cancer. Therefore, we examined STC2 expression as a molecular blood marker for detection of circulating tumor cells (CTCs) and assessed the relationship between STC2 expression and clinico-pathological features including prognosis in patients with gastric cancer. Quantitative PCR assay was used to assess STC2 mRNA expression in 4 gastric cancer cell lines and in blood specimens from 93 patients with gastric cancer and 22 healthy volunteers. The numbers of STC2 mRNA copies were significantly higher in the gastric cancer cell lines and in blood from patients with gastric cancer than in blood from healthy volunteers (P=0.0002 and P=0.01, respectively). STC2 expression was positive in 43 (46.2%) of the 93 patients with gastric cancer, and its expression was significantly correlated with age, depth of tumor invasion, lymph node metastasis, stage and venous invasion (P=0.023, P=0.045, P=0.035, P=0.007 and P=0.027, respectively). The 5-year survival rate was significantly lower in patients with STC2 expression compared to patients without STC2 expression (P=0.014). Our results indicate that STC2 could be a useful molecular blood marker for predicting tumor progression by monitoring CTCs in patients with gastric cancer.

Vascular endothelial growth factor-C and -D expression correlates with lymph node micrometastasis in pN0 early gastric cancer

BACKGROUND AND OBJECTIVES

Vascular endothelial growth factors (VEGF)-C and -D play an important role in lymphangiogenesis, and the expressions of these factors are related to lymphatic invasion and lymph node metastasis in various malignant neoplasms. The present study investigates the expression of VEGF-C and -D in early gastric cancer and analyzes its relationship to lymph node micrometastasis determined by reverse transcription-polymerase chain reaction (RT-PCR).

METHODS

We examined 1,828 lymph nodes obtained from 80 patients with node-negative early gastric cancer. All dissected lymph nodes were examined by RT-PCR for CEA mRNA in addition to hematoxylin-eosin staining. The resected primary specimens were immunostained using anti-VEGF-C and -D polyclonal antibodies.

RESULTS

The incidence of lymph node micrometastasis determined by RT-PCR was 23.8% (19/80). The high expression of VEGF-C and -D was found in 27.5% (22/80) and in 21.3% (17/80), respectively. The expression of VEGF-C and -D was closely related to lymph node micrometastasis (P = 0.0390 and 0.0213, respectively).

CONCLUSIONS

We demonstrated a close relationship between micrometastasis and VEGF-C and -D expression of the primary tumor. Thus, levels of VEGF-C and -D expression might be useful for predicting micrometastasis in patients with early gastric cancer.

Distribution of lymph node metastasis including micrometastasis in gastric cancer with submucosal invasion

The purpose of this retrospective study was to analyze the distribution of lymph node metastases, including micrometastases, according to the location of the gastric cancer with submucosal invasion. A total of 118 patients with submucosal gastric cancer were enrolled in this study. The distribution of lymph node metastases was examined according to tumor location. Immunohistochemical examination using anti-cytokeratin antibody was performed to examine nodal micrometastases in 118 patients. Lymph node metastasis was found in 19.5% (23/118) of the patients. Significant differences were found for tumor size and depth, lymphatic invasion, and venous invasion for patients with and without nodal metastasis. The distribution of lymph node metastasis for tumors at upper or middle portions of the stomach was mainly found along the left gastric artery. The distribution of lymph node metastasis for tumors in the lower and lesser curvature varied. Immunohistochemical analysis found that 15 of 23 patients with lymph node metastasis found by histologic examination had micrometastases. The presence of two or more lymph node micrometastases was found in these 15 patients, and they were distributed in another stations, including distant nodes. The incidence of micrometastasis was 24.2% (23/95) in pN0 patients. Lymph node micrometastases were confined to regional nodes near the primary tumor. When planning minimally invasive treatment for submucosal gastric cancer, it is important to understand the distribution of lymph node metastasis, including micrometastasis, according to tumor location.

Paraaortic lymph node micrometastasis and tumor cell microinvolvement in advanced gastric carcinoma

BACKGROUND: Paraaortic lymph node dissection in advanced gastric carcinoma is controversial. The purpose of this study was to investigate the incidence and significance of micrometastasis (MM) or tumor cell microinvolvement (TCM) in these critical lymph nodes.METHODS: A total of 2339 lymph nodes, including 390 paraaortic nodes, obtained from 47 patients with advanced gastric carcinoma were examined immunohistochemically, using cytokeratin antibody.RESULTS: Lymph node metastasis was found in 95 of the 390 paraaortic nodes of 14 patients by routine histological examination. MM or TCM was immunohistochemically detected in 45 of the 295 negative paraaortic lymph nodes from 15 of 33 patients (MM, n = 5; TCM, n = 10). The 5-year-survival rate in the paraaortic node-negative group and cytokeratin-positive group was significantly higher that that of the hematoxilin and eosin-positive group. The total number of lymph node metastases by hematoxylin and eosin staining and the pathological lymph node compartments, by cytokeratin-positive nodes, were prognostic factors by multivariate analysis.CONCLUSIONS: We demonstrated a high rate of MM or TCM in the paraaortic lymph nodes and suggest that such harbored metastases are related to the prognosis of patients with advanced gastric carcinoma. On the basis of this study, a multi-institutional study should be considered.

Clinical implications of DLL4 expression in gastric cancer

BACKGROUND

Delta-like ligand 4 (DLL4)-Notch signaling plays a key role in tumor neovascular development and angiogenesis during tumor growth. The clinical significance of DLL4 expression in gastric cancer has not been clarified.

METHODS

Gastric cancer cell lines and 180 gastric cancer patients were enrolled. DLL4 expression in gastric cancer cells and stroma was identified and evaluated immunohistochemically. The association between DLL4 and clinicopathological factors was also assessed.

RESULTS

DLL4 expression was identified in the cellular membrane and cytoplasm of gastric cancer cells by immunoblotting and immunohistochemical staining. DLL4 positivity in cancer cells and stroma was found in 88 (48%) and 41 (22%) of the 180 gastric cancer patients respectively. Both cancer and stromal DLL4 expression significantly correlated with more advanced tumor depth, nodal involvement, and lymphatic and venous invasion. A strongly positive association between cancerous and stromal DLL4 expression was identified (p < 0.01). Both cancerous and stromal DLL4 expression were prognostic markers in gastric cancer as determined by univariate analysis.

CONCLUSIONS

Cancerous and stromal DLL4 expression was found in 48% and 22% in gastric cancer, and significantly affected postoperative clinical outcomes. Cancerous and stromal DLL4 expression may be an effective target of anti-DLL4 treatment in gastric cancer.

A Novel Scoring System Based on Fibrinogen and the Neutrophil-Lymphocyte Ratio as a Predictor of Chemotherapy Response and Prognosis in Patients with Advanced Gastric Cancer

<b><i>Objective:</i></b> We assessed the clinical applicability of the F-NLR score, which is based on fibrinogen (F) and the neutrophil-lymphocyte ratio (NLR), and the Glasgow Prognostic Score (GPS) to predict the therapeutic effects of chemotherapy or chemoradiotherapy on advanced gastric cancer and the prognoses of patients. <b><i>Methods:</i></b> Sixty-eight patients with advanced gastric cancer treated with first-line chemotherapy or chemoradiotherapy were classified into two groups based on tumor response. Furthermore, we categorized patients according to cutoff F-NLR scores of 2 [hyperfibrinogenemia (>400 mg/dl) and high NLR (>3.0)], 1 [one of these hematological abnormalities], and 0 [neither hyperfibrinogenemia nor high NLR]. <b><i>Results:</i></b> A total of 27 patients had progressive disease (PD) and 41 did not. The F-NLR scores were significantly higher in the PD than in the non-PD group (p = 0.003). Survival was significantly shorter for patients with high F-NLR scores and GPS (p = 0.0071 and p = 0.0065, respectively). Multivariate analysis selected the F-NLR score as an independent prognostic factor (p = 0.017). <b><i>Conclusion:</i></b> A novel grading system based on F-NLR scores, as well as the GPS, appears to have value as a clinical predictor of the therapeutic response of advanced gastric cancer to chemotherapy or chemoradiotherapy and the prognoses of patients.

Clinical utility of perioperative staging laparoscopy for advanced gastric cancer

Background

Perioperative staging laparoscopy is a useful tool for the detection of occult peritoneal metastases in gastrointestinal cancers. This retrospective study aimed to determine the clinical value of staging laparoscopy for advanced or recurrent gastric cancer.

Methods

A total of 178 patients with advanced or recurred gastric cancer who underwent perioperative staging laparoscopy were enrolled. In the absence of peritoneal deposits (P1) and positive peritoneal cytology (CY1), gastrectomy with lymph node dissection was indicated with curative intent. If P1 or CY1 was detected intraoperatively, patients received intensive chemotherapy and laparoscopic surgical intervention.

Results

Curative gastrectomy was performed in 104 patients after confirmation of P0 and CY0 status. P1 or CY1 was detected for the first time in 23 (15%) patients. A total of 13 patients were converted from gastrectomy to intensive chemotherapy after detection of P1 or CY1. Additional laparoscopic interventions included insertion of intraperitoneal reservoir port in 54 patients, insertion of a metallic stent in five, ileostomy for colon stricture in six, jejunostomy in 19, and gastrojejunostomy in 16. Of eight patients treated with intensive chemotherapy who underwent R0 gastrectomy after second-look laparoscopy, five are currently free from recurrence of gastric cancer for 25.5 months.

Conclusions

Occult peritoneal dissemination was detected in about 14% in patients with tumors deeper than T2. Moreover, additional laparoscopic interventions can be utilized for P1 or CY1 patients. The excellent surgical outcomes of R0 gastrectomy after chemotherapy and second-look laparoscopy indicate that confirmation of P0 and CY0 status by staging laparoscopy is of value to determine treatment strategy in patients with advanced gastric cancer.

Electronic supplementary material

The online version of this article (doi:10.1186/1477-7819-12-350) contains supplementary material, which is available to authorized users.

Disseminated cancer cells in the blood and expression of sialylated antigen in gastric cancer

BACKGROUND

In gastric cancer, disseminated cancer cells (DCC) can be detected in peripheral blood using bio-molecular techniques. It is known that patients having DCC exhibit a high occurrence of postoperative relapse in gastrointestinal cancer. However, more than half of gastric cancer patients having positive DCC do not show cancer relapse. Sialylated Lewis antigens are considered to be crucial molecules in the metastasis of disseminated cancer. The current study investigated whether combination analysis of DCC and sialylated Lewis antigen are useful in estimating the recurrence risk of gastric cancer.

PATIENTS AND METHODS

Subjects were 106 consecutive gastric cancer patients who underwent curative gastrectomy. DCC in the peripheral blood were detected using the carcinoembryonic antigen (CEA)-mRNA by RT-PCR method. Sialylated Lewis antigen expression (sLeA and sLeX) of the primary tumor was assessed immunohistochemically.

RESULTS

Of 106 gastric cancer patients, 43 (40%) were positive for DCC. Immunohistochemically, 53 (50%) and 49 (46%) patients were positive for sLeA and sLeX, respectively. The presence of DCC did not correlate with sLeA and sLeX expression in gastric cancer. Postoperative tumors were present in 19 patients (7 hematogenous and 12 non-hematogenous), 12 of which were positive for DCC. Six sLeA-positive patients (26%) with DCC and 13 sLeX-positive patients (57%) with DCC suffered from postoperative recurrence of gastric cancer. The p value of CEA-mRNA and sLeX combination analysis was more significant (p<0.01) than that of CEA-mRNA alone (p=0.02).

CONCLUSION

Analyzing both DCC and sLeX expression in gastric cancer may enable more accurate prediction of postoperative recurrence.