Clinicopathological and prognostic significance of epidermal growth factor receptor overexpression in patients with esophageal adenocarcinoma: a meta‐analysis

The prognostic significance of epidermal growth factor receptor (EGFR) overexpression in patients with esophageal adenocarcinoma (EAC) remains controversial. Eligible studies that investigated the association between survival in EAC and the expression status of EGFR were identified by an electronic search of PubMed, EMBASE, and ISI Web of Science. A meta‐analysis was performed to clarify the impact of EGFR overexpression on clinicopathological parameters or overall survival (OS) in EAC. A total of seven studies including 1028 patients were subjected to the final analysis. The overall results suggested that overexpression of EGFR was significantly correlated with not only the depth of invasion, lymph node status, and tumors stage of EAC, with a pooled odds ratio of 2.99 (95% confidence interval [CI]: 1.07–8.35; Z = 2.09; P = 0.037), 3.05 (95% CI: 1.77–5.27; Z = 4.00; P < 0.001), and 5.37 (95% CI: 2.49–11.57; Z = 4.29; P < 0.001), respectively, but also the poorer OS with a pooled hazard ratio of 2.20 (95% CI: 1.47–3.31; Z = 3.79; P < 0.001). Overexpression of EGFR correlates with not only the clinicopathological features, but also the worse OS, and it might be useful as a predictive biomarker in clinical practice, yet the clinicopathological and prognostic role of EGFR in EAC still needs further confirmation by well‐designed prospective studies.     

Association between positive murine double minute 2 expression and clinicopathological characteristics of esophageal squamous cell carcinoma: a meta‐analysis

The correlations of murine double minute 2 (MDM2) T309G and esophageal cancer were elucidated because the association between MDM2 expression states and clinicopathological parameters of esophageal squamous cell carcinoma (ESCC) is controversial. We conducted a meta‐analysis on studies screened from PubMed, Web of Science, Embase, the Cochrane Library, and the Chinese Biomedical Literature Databases that were published before October 2014. All studies describing the association between MDM2 and ESCC were traced. Meta‐analysis was performed using the STATA software (Stata Corp., College Station, TX, USA). A total of 9 studies with 707 cases and 324 controls were included. MDM2 expression was higher in ESCC than in normal esophageal epithelium (odds ratio [OR] 10.38, 95% confidence interval [CI] 6.42–16.78, P < 0.001). High MDM2 expression was associated with early primary tumor stage (T1/T2 vs. T3/T4, OR 0.59, 95% CI 0.38–0.92, P = 0.018) and increased risk of regional lymph node metastasis (N0 vs. N1, OR 1.66, 95% CI 1.03–2.67, P = 0.039). However, no relationship was observed between MDM2 expression and the risk of distant metastasis (OR = 2.09, 95% CI 1.00–4.36, P = 0.050), and MDM2 was not significantly correlated with TP53 expression (OR 1.22, 95% CI 0.53–2.77, P = 0.643). Our analysis suggests that MDM2 acts as a potent marker of early primary tumor stage but higher risk of regional lymph node metastasis in ESCC. However, because of the limited number of studies included, the result should be further clarified by well‐designed prospective studies.     

The expression of CXCR4 and its relationship with matrix metalloproteinase‐9/vascular endothelial growth factor in esophageal squamous cell cancer

Esophageal cancer (EC) is a highly aggressive neoplasm with poor prognosis. The main reason for this disappointing outcome is the strong behavior of esophageal cancer cell's invasion and metastasis. CXC chemokine receptor 4 (CXCR4) was found to be expressed in many tumors and significantly correlated with invasion, angiogenesis, metastasis, and prognosis. In the present study, we investigated the expressions of CXCR4, matrix metalloproteinase‐9 (MMP‐9), and vascular endothelial growth factor (VEGF) in esophageal squamous cell cancer (ESCC) and analyzed the relationship among the three proteins. Sections of paraffin‐embedded tissues were obtained from 127 patients with ESCC undergoing esophagectomy at Zhongshan Hospital, Fudan University in 2005. The CXCR4, MMP‐9, and VEGF expressions in EC tissues were evaluated according to the immunohistochemical staining area and intensity. The correlations between patients' prognosis and covariates were analyzed by Kaplan–Meier method (univariate analysis) and Cox regression (multivariate analysis). The overall expression rate of CXCR4, MMP‐9, and VEGF was 88.2%, 93.7%, and 79.5%, respectively. CXCR4 expression was significantly associated with tumor grade, tumor size, tumor depth, regional lymph node metastasis, and tumor, node, metastasis (TNM) stage (P < 0.05). MMP‐9 expression was significantly associated with age and tumor grade (P < 0.05). VEGF expression was significantly associated with tumor grade, tumor depth, and TNM stage (P < 0.05). CXCR4 expression was positively correlated with MMP‐9 expression (P < 0.01, r= 0.365) and VEGF expression (P < 0.01, r= 0.380). However, there was no significant correlation between MMP‐9 and VEGF expression (P > 0.05). In univariate analysis, CXCR4 expression, tumor size, tumor depth, lymph node metastasis, and TNM stage were correlated with patients' prognosis (P < 0.05); in multivariate analysis, tumor size and lymph node metastasis were the independent factors of poor prognosis. CXCR4 was highly expressed in ESCC and correlated with MMP‐9, VEGF, clinicopathological features and prognosis. We speculated CXCR4 play an important role during the progression of this disease and there might be some regulatory mechanism existing between CXCR4 and MMP‐9/VEGF in ESCC.     

Original article: The expression of CFL1 and N‐WASP in esophageal squamous cell carcinoma and its correlation with clinicopathological features

Cofilin1 (CFL1) is an actin‐modulating protein, which belongs to the ADF/Cofilin family. Neural Wiskott–Aldrich syndrome protein (N‐WASP) is the key regulator of the actin cytoskeleton, a member of Wiskott‐Aldrich syndrome protein family. They have been suggested to be involved in cancer cell invasion and metastasis. In this study, the expression patterns of CFL1 and N‐WASP in normal esophageal mucosa and esophageal squamous cell carcinoma (ESCC) and their correlation with clinical characteristics were investigated. Immunohistochemical staining showed that CFL1 was expressed in nuclear and cytoplasm of cancer cells. However, N‐WASP was mainly found in the cytoplasm of the cancer cells. There were significant evidences that proved that CFL1 is correlated with clinicopathological factors in ESCC, such as infiltration depth, lymph node metastasis and pathological staging (P < 0.05). It is also proved that N‐WASP is related to lymph node metastasis and pathological staging in ESCC (P < 0.05). Kaplan–Meier analysis showed that there was no correlation between CFL1 and N‐WASP protein expression and survival (P > 0.05). Moreover, the mRNA expression of CFL1 and N‐WASP was detected by quantitative real time PCR in 70 tissue specimens. The results showed that CFL1 mRNA level was over‐expressed in ESCC tissue (P < 0.05), while N‐WASP mRNA expression level was not different between cancerous tissues and adjacent normal esophageal mucosa (P > 0.05). Also, CFL1 mRNA expression was significantly associated with regional lymph node metastasis and pathological staging (P < 0.05). Kaplan–Meier analysis showed that there was no correlation between CFL1 and N‐WASP mRNA expression and survival (P > 0.05). Our findings suggested that CFL1 and N‐WASP may play an important role in the tumorigenesis of ESCC, and to be the candidate novel biomarkers for the diagnosis and prognosis of ESCC. These findings may have implications for targeted therapies in patients with ESCC.     

Distinct features of distant metastasis and lymph node stage in lung adenocarcinoma patients with epidermal growth factor receptor gene mutations

BackgroundThe influence of epidermal growth factor receptor (EGFR) mutation status on distant and lymph node metastasis is not fully understood.MethodsNinety-five consecutive patients with stage IV lung adenocarcinoma, who had been examined for the EGFR mutation status, were retrospectively analyzed with regard to numbers of distant metastasis and clinical stage of lymph node metastasis at the time of diagnosis.ResultsWhile EGFR mutation status did not influence the presence or absence of distant metastasis in the lung, brain, or liver, patients with EGFR mutations demonstrated a significantly greater number of metastatic lesions in the lung (median: 85 vs. 4, P=0.01) and the brain (11 vs. 3.5, P=0.04). On the other hand, patients with EGFR mutations showed a significantly lower lymph node staging (P<0.01).ConclusionThe presence of EGFR mutations in patients with lung adenocarcinoma correlates with lower lymph node stage and a greater number of metastatic lesions in the lung and brain.     

Treatment strategy for rectal carcinoids: A clinicopathological analysis of 229 cases at a single cancer institution

Background and Aim: A treatment strategy for tumors with only venous invasion and characteristics of small rectal carcinoids with metastasis have not been clearly documented. The present study aims to determine the risk factors for lymph node metastasis and to elucidate characteristics of small tumors with metastasis. Methods: We investigated a total of 229 patients with rectal carcinoids. The relationship between each clinicopathological variable and the presence of lymph node metastasis was evaluated. Results: Tumor size (larger than 10 mm), presence of central depression, depth of tumor invasion, lymphatic invasion, and venous invasion were significantly associated with the incidence of lymph node metastasis (P < 0.001). Multivariate analysis revealed that tumor size (odds ratio: 63.3, P < 0.001) and venous invasion (odds ratio: 40.9, P < 0.001) were independently predictive of lymph node metastasis. In 204 patients with small (no larger than 10 mm) tumors, 10 patients had lymph node metastasis. All 10 tumors had low proliferation values indicated by mitosis and Ki‐67 index. Multivariate analysis for the 204 patients revealed that only venous invasion was independently associated with metastasis (odds ratio: 40.1, P < 0.001). Five‐year disease free survival rates of the total patients with metastasis and without metastasis were 81.1% and 95.5%, respectively (P < 0.001, log‐rank test). Conclusions: Venous invasion as well as tumor size and lymphatic invasion indicates high malignant potential to metastasize to lymph node and would provide useful information in considering the addition of radical surgery. Postoperative pathological examinations of specimens obtained by local resection are very important to avoid underestimation.     

Association of mu‐opioid receptor expression with lymph node metastasis in esophageal squamous cell carcinoma

The mu‐opioid receptor (MOR), a membrane‐bound G protein‐coupled receptor, is the main target for opioids in the nervous system. MOR1 has been found in several types of cancer cells and reported to be involved in tumor progression and metastasis. However, the expression and clinical significance of MOR1 in esophageal squamous cell carcinoma (ESCC) remain unclear. In our study, the expression of MOR1 was confirmed in ESCC cell lines (KYSE180, KYSE150, and EC109) by Western blot. MOR1 was also detected on tissue microarrays of ESCC samples in 239 cases using immunohistochemical staining. We found that MOR1 was mainly located in the cytoplasm and occasionally occurred in the membrane or nucleus of ESCC cells. Moreover, results indicated that MOR1 expression in the cytoplasm was associated with lymph node metastasis (R = 0.164, P = 0.008, Kendall's tau‐b‐test). No more associations were found between MOR1 expression status and other clinical parameters. However, no statistical significant differences were found between MOR1 expression in the cytoplasm, nucleus/membrane, and the overall survival of ESCC patients (P = 0.848; P = 0.167; P = 0.428, respectively, log‐rank test). Our results suggest that the cytoplasmic MOR1 may be a high‐risk factor for lymph node metastasis of ESCC patients. We also hypothesize that MOR1 agonists used in ESCC patients should be prudent, and opioid receptor antagonists may be novel therapeutic drugs for ESCC patients.     

Clinicopathologic factors and molecular markers related to lymph node metastasis in early gastric cancer

AIM: To analyze predictive factors for lymph node metastasis in early gastric cancer.METHODS: We analyzed 1104 patients with early gastric cancer(EGC) who underwent a gastrectomy with lymph-node dissection from May 2003 through July 2011. The clinicopathologic factors and molecular markers were assessed as predictors for lymph node metastasis. Molecular markers such as microsatellite instability, human mut L homolog 1, p53, epidermal growth factor receptor(EGFR) and human epidermal growth factor receptor 2(HER2) were included. The χ2 test and logistic regression analysis were used to determine clinicopathologic parameters.RESULTS: Lymph node metastasis was observed in 104(9.4%) of 1104 patients. Among 104 cases of lymph node positive patients, 24 patients(3.8%) were mucosal cancers and 80 patients(16.7%) were submucosal. According to histologic evaluation, the number of lymph node metastasis found was 4(1.7%) for well differentiated tubular adenocarcinoma, 45(11.3%) for moderately differentiated tubular adenocarcinoma, 36(14.8%) for poorly differentiated tubular adenocarcinoma, and 19(8.4%) for signet ring cell carcinoma. Of 690 EGC cases, 77 cases(11.2%) showed EGFR overexpression. HER2 overexpression was present in 110 cases(27.1%) of 406 EGC patients. With multivariate analysis, female gender(OR = 2.281, P = 0.009), presence of lymphovascular invasion(OR = 10.950, P 0.0001), diameter(≥ 20 mm, OR = 3.173, P = 0.01), and EGFR overexpression(OR = 2.185, P = 0.044) were independent risk factors for lymph node involvement.CONCLUSION: Female gender, tumor size, lymphovascular invasion and EGFR overexpression were predictive risk factors for lymph node metastasis in EGC.     

Overexpression of MMP‐2 and MMP‐9 in esophageal squamous cell carcinoma

Matrix metalloproteinases (MMPs) are known to play important roles in extracellular matrix remodeling during the process of tumor invasion and metastasis. However, little is known about their role in esophageal squamous cell carcinoma (ESCC). Expression of MMP‐2 and MMP‐9 in ESCC was detected in our research. Tissue microarray chip was prepared, consisting of 58 cases of ESCC and corresponding esophageal epithelium tissues. MMP‐2 and MMP‐9 were examined by immunohistochemistry. Overexpression of MMP‐2 and MMP‐9 was found in ESCC (42.1 and 60.3%, respectively), compared with paired distal normal esophageal tissues (22.9 and 8.9%, respectively). Expression of MMP‐2 in ESCC was significantly associated with the tumor invasion depth, tumor‐node‐metastasis stages, and lymph node metastasis. MMP‐2 and MMP‐9 may play important roles in carcinogenesis, and MMP‐2 may act as a biological marker of invasion and lymph node metastasis in ESCC.     

MIXED INTESTINAL‐ AND DIFFUSE‐TYPE HISTOLOGY IS A RISK FACTOR FOR LYMPH NODE METASTASIS OF SUBMUCOSAL INVASIVE GASTRIC CANCER

Background: Endoscopic submucosal dissection is expected to increase the number of node‐negative submucosal invasive gastric cancers, particularly differentiated‐type adenocarcinomas that can be treated conservatively. Methods: Two hundred and seven consecutive surgically treated cases of differentiated‐type early gastric cancer with submucosal invasion were analyzed clinicopathologically. Comparison was made between patients with node‐positive (n = 33) and node‐negative cancer (n = 174). Whole sections of surgical specimens were reviewed and reclassified as pure intestinal type or mixed type. The intramucosal and submucosal components were also described histologically, and the depth of invasion from the muscularis mucosae as well as the width of submucosal invasion was measured. Results: Twenty‐four of 33 (73%) node‐positive cases were of the mixed type, whereas 71 of 174 (41%) node‐negative cases were of the mixed type (P < 0.01). As for the intramucosal histology, the ratio of mixed‐type was also higher in the node‐positive group (58% vs 34%; P < 0.05). Other factors associated with lymph node metastasis were larger tumor size (P = 0.003), deeper submucosal invasion (P < 0.001) and wider submucosal extension (P = 0.004), and lymphatic permeation (P < 0.001). Multivariate analysis demonstrated that lymphatic permeation (P = 0.001, OR 4.76), and mixed‐type histology (OR 2.56) were independent risk factors. Conclusions: Histological heterogeneity is a risk factor for metastasis of submucosal invasive gastric cancer to lymph nodes. Heterogeneity of mucosal components is also a significant risk factor and thus a good predictor of lymph node metastasis, potentially useful in distinguishing patients ineligible for conservative therapy.     

Human papillomavirus type 16 infection may be involved in esophageal squamous cell carcinoma carcinogenesis in Chinese Kazakh patients

The aim of this study was to investigate human papillomavirus type 16 (HPV16) prevalence in esophageal squamous cell carcinoma (ESCC) in Xinjiang Kazakh patients and its role in ESCC carcinogenesis. One hundred and fifty cases of ESCC and 150 cases of corresponding normal esophageal mucosa (CNGM) samples were collected from north Xinjiang where the Kazakh ethnic group has lived since ancient times. HPV16 infection in ESCC and CNGM was detected by genotype‐specific polymerase chain reaction. HPV16 DNA was detected in 55 of 150 ESCC samples (36.7%) and 24 of 150 corresponding normal esophageal mucosa samples (16%) with significant differences (P < 0.001, odds ratio = 3.039, 95% confidence interval: 1.756–5.260). No statistically significant correlations were found between HPV16 infection and the age or gender of patients, tumor site, tumor cell differentiation, or lymph node metastasis (P > 0.05). HPV16 infection is common in cases of ESCC in the Kazakh ethnic group in Xinjiang and may be involved in ESCC carcinogenesis.     

Overexpression of cyclooxygenase‐2 is associated with chemoradiotherapy resistance and prognosis in esophageal squamous cell carcinoma patients

Our objective was to investigate whether cyclooxygenase‐2 (COX‐2) expression can predict the patient's response to chemoradiotherapy (CRT) and ensuing prognosis in esophageal squamous cell carcinoma (ESCC). The clinicopathological and follow‐up data of 112 patients with ESCC who underwent CRT from January 2001 to June 2006 were analyzed retrospectively. The immunohistochemical expression level of COX‐2 was examined for all biopsy specimens of primary tumors, and the correlation of COX‐2 expression with the patient's response to CRT and prognosis was examined. COX‐2 positive immunostaining was detected in 111 (99.1%) of the patients, including overexpression in 54 (48.2%) patients and low expression in 58 (51.8%) of the patients. The response of tumors with a low level expression of COX‐2 (70.7%, 41/58) was significantly higher than that of tumors with COX‐2 overexpression (42.6%, 23/54; P = 0.003). Patients with a low level of COX‐2 expression had a higher downstaged rate than those with a high level of COX‐2 expression (9/13 vs 2/8), but the difference was not statistically significant (P = 0.08). In the definitive CRT group (91 cases), COX‐2 overexpression was significantly associated with poor 3‐year overall survival (P = 0.028). Multivariate analysis showed that only metastatic stage (nonregional node metastasis) was an independent prognosis factor. The assessment of COX‐2 status may provide additional information to identify ESCC patients with poor chances of response to CRT and potential candidates for more individualized treatment.     

Risk factors for lymph node metastasis of submucosal invasive differentiated type gastric carcinoma: clinical significance of histological heterogeneity

Background. The use of endoscopic resection for submucosal invasive gastric carcinoma (Sm-ca) with histologically differentiated type has been expected. However, the treatment criteria remain controversial. The purpose of this study was to clarify the relationship between lymph node metastasis and the histologic features of differentiated Sm-ca. Methods. The clinicopathologic features of 35 patients with node-positive differentiated Sm-ca were compared with those of 221 patients with node-negative differentiated Sm-ca by multivariate analysis with logistic regression. To clarify the metastatic behavior of differentiated Sm-ca, we examined mucin-histochemical expression and immunohistochemical staining, using Ki-67, p53, and c-erbB2. Results. The rate of lymph node metastasis was significantly higher in differentiated Sm-ca with histologi-cal heterogeneity (combined differentiated type, with poorly differentiated component) than in that without histological heterogeneity (27% vs 7%; P < 0.001). Multivariate analysis revealed that lymphatic vessel invasion was the most significant determinant (odds ratio, 8.68) for lymph node metastasis. Histological heterogeneity (odds ratio, 3.88) was next, followed by papillary adenocarcinoma (odds ratio, 3.28), and submucosal invasion level (odds ratio, 2.34). The mean value of the Ki-67 labeling index for node-positive differentiated Sm-ca was higher than that of node-negative differentiated Sm-ca (47% vs 39%; P < 0.05). Conclusions. When the extension of endoscopic surgery to differentiated Sm-ca is considered, this therapeutic technique should be limited to the differentiated type of Sm-ca without histological heterogeneity. The Ki-67 labeling index provides useful information for identifying those patients with a high risk of lymph node metastasis. Received: January 9, 2001 / Accepted: April 13, 2001     

Histopathologic characteristics of colorectal cancer with liver metastasis

PURPOSE: Although prognostic factors of colorectal cancer have been studied, factors associated with liver metastasis have not been fully investigated. The aim of this study was to clarify the histopathologic characteristics of colorectal cancer with liver metastasis. METHODS: We performed a retrospective histopathologic study on 335 patients who underwent resection of colorectal cancer during 15 years. Histopathologic parameters of tumors with liver metastasis were compared with those without liver metastasis. RESULTS: Forty-one patients (12 percent) had simultaneous liver metastasis. Tumors having liver metastasis, when compared with those not having liver metastasis, were characterized by high frequency of tumor size more than 6 cm (51vs. 28 percent;P<0.01), presence of serosal invasion (98vs. 66 percent;P<0.01), lymphatic invasion (34vs. 15 percent;P<0.01), venous invasion (24vs. 3 percent;P<0.01), and lymph node metastasis (85vs. 39 percent;P<0.01). Multivariate analysis showed that factors independently associated with liver metastasis were serosal invasion, venous invasion, and lymph node metastasis. Accuracy in the diagnosis of liver metastasis was highest for venous invasion (88 percent) and lowest for serosal invasion (41 percent). Among 98 patients with both serosal invasion and lymph node metastasis, tumors with and without liver metastasis were different in frequency of venous invasion (26vs. 6 percent;P<0.01) and extracolic lymph node metastasis (68vs. 47 percent;P<0.05). CONCLUSION: In colorectal cancer important factors associated with liver metastasis were serosal invasion, venous invasion, and lymph node metastasis. Significant determinants for liver metastasis from colorectal cancer were venous invasion and extracolic lymph node metastasis.Presented at the meeting of The Japanese Society for Cancer of the Colon and Rectum, Tokyo, Japan, July 4, 1997.     

Relationship between altered expression levels of MIR21, MIR143, MIR145, and MIR205 and clinicopathologic features of esophageal squamous cell carcinoma

In spite of the undisputed importance of altered expression patterns of microRNAs (miRNAs) in various cancers, there is little information on the clinicopathologic significance of cancer‐related miRNAs (MIR21, MIR143, MIR144, MIR145, and MIR205) in esophageal squamous cell carcinoma (ESCC). We examined the expression levels of the precursor and mature miRNA genes in ESCC using real‐time polymerase chain reaction (PCR). We also investigated the mRNA expression levels of processing elements (RNASEN, DGCR8, and DICER1) that participate in miRNA‐biogenesis pathway. Furthermore, we analyzed the relationships between the expression levels of these five miRNAs and the clinicopathologic parameters of ESCC patients. The expression levels of mature MIR21 and mature MIR145 were higher in ESCC than those in normal epithelium (P < 0.05). The mature/pre ratio of MIR21 in ESCC was higher than that in normal epithelium (P < 0.05). With regard to miRNA‐processing elements, the expression level of RNASEN was higher in ESCC than in normal epithelium (P < 0.05). Furthermore, altered expression of these miRNAs was related to the clinicopathologic features of ESCC patients. The high expression of mature MIR21 and mature MIR205 was associated with lymph node positivity in ESCC patients (P < 0.05). The high levels of expression of mature MIR143 and mature MIR145 were associated with recurrence of metastasis in ESCC patients (P < 0.05). The findings may imply that miRNA biogenesis is aberrantly accelerated in ESCC. Analysis of the expression levels of miRNAs should provide useful information for evaluation of the staging, prognosis, and treatment of ESCC patients.     

The significance of abdominal para‐aortic lymph node metastasis in patients with lower thoracic esophageal cancer

Para‐aortic lymph node (PALN) recurrence is often seen in patients with lower thoracic esophageal cancer treated by esophagectomy with extended lymph node dissection. However, the clinicopathological characteristics of patients with PALN metastasis and the significance of PALN dissection are unknown. A total of 283 patients with lower thoracic esophageal cancer underwent esophagectomy with lymphadenectomy at our hospital between April 1984 and March 2007. Among these 283 patients, 60 patients were enrolled in this retrospective study according to following criteria: (i) clinical T2 to T4 tumor, (ii) no clinical PALN metastasis, and (iii) received PALN dissection. PALN dissection was indicated by a tumor depth of at least T2 and no severe complications. The clinicopathological data, recurrence pattern, and overall survival were compared between patients with PALN and without PALN metastasis. The mean length of surgery was 587 min and the mean blood loss was 1383 mL. The morbidity was 33.3% and mortality was 5% in this series. Sixteen patients (26.7%) had PALN metastasis; these showed significantly more lymph node metastases (15.8 ± 13.2 vs. 3.0 ± 3.2, P < 0.0001) and significantly worse survival rates (53.3% vs. 79.9% at 1 year, 6.7% vs. 62.0% at 3 years, P < 0.0001) than patients without PALN metastasis. The incidence of lymph node recurrence (P < 0.0001) and hematogenous recurrence (P= 0.0487) was also higher in patients with PALN metastasis than in patients without PALN metastasis. Among the 16 patients with PALN metastasis, a univariate analysis revealed total number of metastatic nodes < 8 (P= 0.0325) to be a significant prognostic factor. A multivariate logistic regression analysis of the regional lymph nodes identified the invasion of the lower mediastinal nodes (hazard ratio = 6.120) and retroperitoneal nodes (hazard ratio = 15.167) to be significantly correlated with PALN metastasis. PALN metastasis is suggested to be related to the systemic spread of lymphatic metastasis even in lower thoracic esophageal cancer. PALN dissection for pathological PALN(+) patients should not be performed. It remains to be determined in future prospective studies whether patients without pathological PALN metastasis, but showing PALN micrometastasis, could achieve improved survival with PALN dissection.     

Expression of COX-2 proteins in gastric mucosal lesions

AIM: To investigate the expression of COX-2 proteins in gastric mucosal lesions and to assess the relationship between COX-2 expression and type, pathologic stage, differentiation, or lymph node metastasis in gastric cancer and the relationship between COX-2 expression and H pylori infection in gastric mucosal lesions. METHODS: Thirty patients with gastric carcinoma underwent surgical resection. Samples were taken from tumor site and paracancerous tissues, and ABC immunohistochemical staining was used to detect the expression of COX-2 proteins. H pylori was determined by rapid urea test combined with pathological stating/14C urea breath test. RESULTS: The positive rate and staining intensity of mutant COX-2 gene expression in gastric cancer were significantly higher than those in paracancerous tissues (66.7% vs 26.7%) (P<0.01, P<0.001). There was a significant correlation between COX-2 and pathologic stage or lymph node metastasis type of gastric carcinoma (76.0% vs 20.0%, 79.2% vs 16.7%) (P<0.05). No correlation was found between COX-2 expression and type or grade of differentiation (P>0.05). COX-2 expression of intestinal metaplasia (IM) or dysplasia (DYS) with positive H pylori was significantly higher than that with negative H pylori (50.6% vs 18.1%, 60.0% vs 33.3%) (P<0.05). CONCLUSION: COX-2 overexpression was found in a large proportion of gastric cancer tissues compared with matched non-cancerous tissues and was significantly associated with advanced tumor stage and lymph node metastasis. Overexpression of COX-2 plays an important role in tumor progression of gastric cancer. COX-2 may also play a role in the early development/promotion of gastric carcinoma and is associated with H pylori infection.     

Comparison between `in vivo' and `in vitro' methods for evaluating tumor angiogenesis using cervical carcinoma as a model

The role of angiogenesis in tumorigenesis is widely accepted. Therefore, it is mandatory to develop a clinically useful method for assessing tumor angiogenesis. This study was designed to compare the `in vivo' and `in vitro' methods for assessing angiogenesis and to evaluate their clinical application using cervical carcinoma as a model. Ninety women with stages IB-IIA cervical carcinoma exhibiting visible cervical tumors by transvaginal ultrasound were enrolled in this study. All patients underwent radical abdominal hysterectomy and pelvic lymph node dissection. Vascularity index (VI) was assessed by power Doppler ultrasound and a quantitative image processing system. The microvessel density (MVD) of the excised tumors was immunohistochemically assessed. Both the enzyme immunoassay and immunohistochemistry methods were performed for assessing the protein levels of vascular endothelial growth factor (VEGF) in tumor tissues. Significantly higher VI, MVD and cytosol VEGF concentrations were detected in tumors with deep stromal invasion (≥1/2 thickness) (11.43 ± 7.25 vs. 5.87 ± 6.81, P < 0.001; 53.0 vs. 37.0, P = 0.006, 550.0 vs. 86.0 pg/mg, P < 0.001), lymphatic invasion (12.21 ± 7.89 vs. 6.86 ± 6.29, P < 0.001; 53.0 vs. 40.0, P = 0.038; 930.0 vs. 110.0 pg/mg, P = 0.002), and pelvic lymph node metastasis (17.15 ± 8.58 vs. 7.83 ± 6.41, P < 0.001; 54.0 vs. 39.0, P = 0.02; 964.0 vs. 131.0 pg/mg, P = 0.002). VEGF-rich tumors detected by immunohistochemistry also revealed higher VI (12.26 ± 7.96 vs. 8.05 ± 7.62, P = 0.012), MVD (53.0 vs. 37.5, P = 0.01) and cytosol VEGF levels (745.0 vs. 98.0 pg/mg, P = 0.002). The relationships between VI values, MVD values and cytosol VEGF concentrations were linear (VI vs. MVD, r = 0.38, P < 0.001; VI vs. VEGF, r = 0.78, P < 0.001; MVD vs. VEGF, r = 0.29, P = 0.006). As revealed by the receiver operating characteristic (ROC) curve analysis, VI is better than MVD and VEGF in predicting lymph node metastasis. In conclusion, there is histological, molecular and clinical evidence supporting VI as a useful `in vivo' indicator of tumor angiogenesis, particularly for predicting lymph node metastases in cervical carcinomas. This revised version was published online in June 2006 with corrections to the Cover Date.