Regional lymph node staging and establishment of prognostic model for stage III( colon cancer / 中华胃肠外科杂志

<p><b>OBJECTIVE</b>To evaluate the clinical value of different regional lymph node staging system and to establish a predictive prognostic model for stage III( colon cancer.</p><p><b>METHODS</b>A total of 256 Patients with stage III( colon cancer from January 1999 to December 2008 were identified from the China Medical University Cancer and underwent radical surgery. Based on information on regional lymph nodes, lymph nodes were staged LNR staging using pN stage in the 7th edition of the AJCC, the jN stage of the JGR, and LNR-stage on the basis of Log-rank statistics, respectively. Using the linear trend chi-square test, likelihood ratio Chi-square test, concordant index(c-index) to evaluate the homogeneity, monotonicity, and discrimination power of the staging system. Univariate and multivariate analyses were used to determine the clinical and pathological prognostic impact factors. After relevant diagnostic models were established, the Akaike Information Criterion (AIC) value was calculated to compare and identify the best diagnostic model.</p><p><b>RESULTS</b>Log-rank statistics found that 0.11 and 0.39 were the optimal cut-off point. LNR staging system included LNR1 (LNR<0.11), LNR2 (0.11,0.39), and LNR3(0.39,1). The concordance indices were 0.624 for pN, 0.611 for jN, and 0.700 for LNR. The heterogeneity was the lowest for LNR. Cox regression model was used to establish prognostic models for pN, jN, and LNR, and the AIC was 99.937, 71.631, and 65.548, respectively. The prognostic value was the highest for LNR.</p><p><b>CONCLUSION</b>LNR staging is the ideal staging system for stage III( colon cancer patients, which is better than the latest version of the current AJCC pN stage and JGR jN staging.</p>

Comparison of clinicopathological features and prognosis in familial and sporadic gastric cancer / 中华胃肠外科杂志

<p><b>OBJECTIVE</b>To analyze the clinicopathological characteristics and prognosis of familial gastric cancer and to improve the treatment outcome.</p><p><b>METHODS</b>Clinical data of 67 patients with familial gastric cancer and 820 patients with sporadic gastric cancer in the Second Affiliated Hospital of Dalian Medical University from 1995 to 2005 were retrospectively analyzed.</p><p><b>RESULTS</b>Compared to sporadic gastric cancer, the percentage of familial gastric cancer patients less than 45 years old was higher (34.3% vs. 14.6%). Early gastric cancer(23.9% vs. 13.8%), diffuse gastric cancer(79.1% vs. 29.0%), and lymph node metastasis (91.0% vs. 70.9%) were more common in patients with familial cancer(P<0.05). The 5-year survival rate of familial gastric cancer patients was lower than that of patients with sporadic gastric cancer(20.5% vs. 45.1%)(P<0.05).</p><p><b>CONCLUSIONS</b>Familial gastric cancer has characteristics of younger onset age, advanced disease staging, higher positive lymph node ratio and poorer prognosis. Therefore, early diagnosis should be emphasized in the management of familial gastric cancer.</p>

5-Aza-CdR regulates the expression of RASSF1A gene in human gastric cancer cell line and inhibits the growth of cells / 中华胃肠外科杂志

<p><b>OBJECTIVE</b>To investigate the effect of demethylating agent 5-Aza-CdR (5-aza-2'- deoxycytidine) on demethylation and transcription-regulating of RASSF1A gene in gastric cancer cell SGC7901 in vitro, as well as on the growth inhibition of cells.</p><p><b>METHODS</b>After SGC7901 cells were treated with 5-Aza-CdR, MTT assay, flow cytometry, and Annexin V-FITC staining were performed to analyze the cell proliferation, cell cycle and apoptotic rate respectively. Methylation- specific PCP (MSP), RT-PCR and Western blotting were used to detect methylation state, expression of mRNA and protein of RASSF1A gene.</p><p><b>RESULTS</b>After SGC7901 cells were treated with different concentrations of 5-Aza-CdR, the cell growth was inhibited(P<0.05), the cell cycle was blocked at G(1) phase, and the apoptotic rate increased significantly(P<0.05). Hypermethylation was detected in the promoter region of RASSF1A gene in SGC7901 cells, and no expression of RASSF1A mRNA and protein was found. After treated with 5-Aza-CdR, demethylation occurred in RASSF1A gene,which subsequently induced re-expression of this gene at both mRNA and protein level.</p><p><b>CONCLUSION</b>Demethylating agent 5-Aza-CdR can regulate demethylation and re-expression of RASSF1A gene in gastric cancer cell SGC7901,and inhibit its growth.</p>

Effects of 5-Aza-2'-deoxycytidine and trichostatin A on P16, hMLH1 and MGMT genes and DNA methylation in human gastric cancer cells / 中华胃肠外科杂志

<p><b>OBJECTIVE</b>To investigate the effects of 5-Aza-2'-deoxycytidine (5-Aza-dC) and trichostatin A (TSA) on DNA methylation and expression of P16, hMLH1 and MGMT genes in the human gastric cancer cell line MGC-803, and to explore the mechanism of P16, hMLH1 and MGMT gene silencing in human gastric cancer cells.</p><p><b>METHODS</b>MGC-803 cells were cultured in RPMI-1640 medium and were treated with 5-Aza-dC or TSA. Methylation-specific polymerase chain reaction (MS-PCR) was used to detect the promoter methylation status of P16, hMLH1 and MGMT genes. RT-PCR was used to detect the mRNA expressions of P16, hMLH1 and MGMT.</p><p><b>RESULTS</b>Promoter hypermethylation of P16, hMLH1 and MGMT genes were detected in MGC-803 cells, and mRNA expressions of P16, hMLH1 and MGMT were absent before treatment. After treatment with 5-Aza-dC, the promoter region of the P16, hMLH1 and MGMT gene exhibited a demethylation status, and their mRNA expressions were increased. The treatment with TSA had no effects on DNA demethylation or restoration of P16 or hMLH1 expression. P16, hMLH1 and MGMT mRNA relative expression levels after treatment with a combination of 5-Aza-dC and TSA were 0.412+/-0.030, 0.397+/-0.024 and 0.553+/-0.043 respectively, which were higher than those after 5-Aza-dC treatment alone (0.221+/-0.022, 0.214+/-0.018 and 0.156+/-0.017, all P<0.05).</p><p><b>CONCLUSIONS</b>Promoter hypermethylation is a major mechanism of P16, hMLH1 and MGMT gene silencing in human gastric cancer cells. Treatment with 5-Aza-dC alone or the combination of 5-Aza-dC and TSA can reactivate the expressions of these genes.</p>

Lymphadenectomy adjacent to inferior mesenteric artery root during radical operation and prognosis in rectal cancer / 中华胃肠外科杂志

<p><b>OBJECTIVE</b>To investigate the effect of lymphadenectomy adjacent to inferior mesenteric artery root on the prognosis of rectal cancer.</p><p><b>METHODS</b>Clinicopathological data of 260 cases with rectal cancer undergone radical operation were analyzed retrospectively. The patients were divided into two groups. Group D(2): the lymph nodes adjacent to mesenteric artery root were not excised (n=188). Group D(3): the lymph nodes adjacent to mesenteric artery root were excised (n=72). Prognosis of two groups was compared during the follow-up period.</p><p><b>RESULTS</b>In group D(2), the 1-, 3-, 5-year total survival rates (TS) were 97.3%, 87.2% and 77.1%, and tumor-free survival rates (TFS) were 93.1%, 83.0% and 76.8% respectively. In group D(3 ), the 1-, 3-, 5-year total survival rates (TS) were 94.4%, 79.2% and 73.6%, and tumor-free survival rates (TFS) were 86.1%, 76.4% and 71.0% respectively. The differences of TS and TFS between two groups were not significant according to Kaplan-Meier analysis (P>0.05). Multivariate analysis revealed that the excision of lymph nodes adjacent to mesenteric artery root was not statistically correlated with the recurrence, metastasis and survival time after radical operation of rectal cancer.</p><p><b>CONCLUSION</b>Excision of lymph nodes adjacent to inferior mesenteric artery root has no significant impact on prognosis and it is unnecessary in the radical operation of rectal cancer.</p>

Diagnosis and surgery treatment of gastric neurogenic tumors / 中华胃肠外科杂志

<p><b>OBJECTIVE</b>To summarize the clinical characteristics, diagnosis and treatment of gastric neurogenic tumors.</p><p><b>METHODS</b>Clinical data of 11 patients with gastric neurogenic tumors confirmed by pathology, operation and immunohistochemistry were analysed retrospectively.</p><p><b>RESULTS</b>There were 7 males and 4 females with a median age of 55.5 years. The main manifestations were gastrointestinal hemorrhage, abdominal pain, upper abdominal discomfort and anaemia. Nine patients underwent gastroscopy and only one case was confirmed by the examination. Two patients were diagnosed during operation. Eight patients were submitted to subtotal gastrectomy, three were partial gastrectomy. All patients were followed up, and perioperative death occurred in one patient because of respiratory failure, recurrence occurred in two patients. Other patients with long- term follow- up had a good prognosis.</p><p><b>CONCLUSIONS</b>Gastric neurogenic tumors have no specific clinical characteristics preoperatively, and the misdiagnosis rate is high. Once the diagnosis of gastric neurogenic tumors is made, an operation should be performed as early as possible.</p>

A comparative study of E-cadherin mRNA expression in primary tumors and metastatic foci of gastric cancer / 中华肿瘤杂志

<p><b>OBJECTIVE</b>To evaluate the expression level of E-cadherin (E-CD) mRNA in gastric cancer and its relation to biological behavior.</p><p><b>METHODS</b>The expression level of E-CD mRNA was examined by RT-PCR in primary tumors, nearby tumor free tissues, metastatic lymph nodes and peritoneal lavage fluid from 35 cases with advanced gastric cancer.</p><p><b>RESULTS</b>All the specimens expressed E-CD mRNA. The expression level in primary tumors was significantly decreased compared with that in nearby tumor free tissues (P < 0.01). The decrease in E-CD expression was more marked in poorly differentiated, diffusely growing tumors invading through serosal membrane. E-CD expression in the primary tumor was more significantly decreased with the increase in the number of lymph nodes (LNS) metastasized and progression of the clinical stage. However, E-CD expression level was significantly increased in metastatic LNs. The difference in E-CD mRNA level between metastatic LN and the primary tumor was increasing with progression of the disease. The expression level of E-CD mRNA in peritoneal lavage fluid was increased in patients whose tumor had penetrated through serosa and larvage fluid was positive on exfoliative cytologic examination.</p><p><b>CONCLUSION</b>E-CD mRNA expression in primary tumors of gastric cancer is negatively correlated with the malignant behavior of the tumor. Nonetheless, that in the metastatic lymph nodes is increased with the progression of the disease.</p>