Emergence application of colonoscopic placement of self-expandable metal stent without fluoroscopic monitoring / 中华胃肠外科杂志

<p><b>OBJECTIVE</b>To evaluate the efficacy and safety of colonoscopy-guided placement of self-expandable metallic stent without fluoroscopic monitoring in the emergence management for acute malignant colorectal obstruction.</p><p><b>METHODS</b>Clinical data of 42 patients (24 males and 18 females with a mean age of 64.3 years) undergoing colonoscopy-guided placement of self-expandable metallic stents without fluoroscopic monitoring for acute malignant colorectal obstruction between January 2010 and June 2012 were reviewed retrospectively.</p><p><b>RESULTS</b>The obstruction was located in the rectum (n=19), sigmoid (n=9), descending colon (n=8), splenic flexure (n=1), hepatic flexure (n=3), and ascending colon (n=2). Technical success was achieved in all the 42 patients (100%). The mean time of operation was (11.8±10.4) min (range 1.1-51.0 min). No serious procedure-related complication occurred. Minor bleeding occurred in 3 cases (7.1%). One patient died on the second day after surgery because of heart failure.</p><p><b>CONCLUSIONS</b>Colonoscopy-guided placement of self-expandable metallic stents without fluoroscopic monitoring in emergence management for acute malignant colorectal obstruction is effective and safe with shorter operative time.</p>

Surgical treatment strategies for locally advanced rectal cancer after neoadjuvant radiation / 中华胃肠外科杂志

For locally advanced rectal cancer after neoadjuvant radiation, it is difficult to make a choice between close observation, local resection, and radical resection. The decision should be made after carefully weighing postoperative complications, anal function, local recurrence and long-term survival. There is a high consistency of the radiosensitivity between primary tumor and mesenteric lymph node, which may be used to guide the treatment decisions. If the primary tumor shrinks significantly after neoadjuvant radiation, local resection is recommended, and the next treatment plan should be made based on the pathological examination of resected specimen. Transabdominal radical resection is recommended for unfavorable tumors. Distal resection margin should be at least 1 cm, and marking the inferior margin of tumor is also recommended before neoadjuvant radiation since it would shrink significantly after radiation.

Association of epithermal growth factor receptor expression and its downstream gene mutation status with radiosensitivity of colorectal carcinoma cell lines in vitro / 中华胃肠外科杂志

<p><b>OBJECTIVE</b>To investigate the effect of epithermal growth factor receptor (EGFR) expression and K-ras, B-raf and PIK3CA mutation status on the radiosensitivity of human colorectal carcinoma (CRC) cell lines in vitro.</p><p><b>METHODS</b>Real-time RT-PCR was used to measure EGFR mRNA expression in nine human CRC cell lines, and K-ras, B-raf and PIK3CA mutation status of each CRC cell line was also identified respectively. After treatment with irradiation at graded dose, the cell viability was measured by clonogenic survival assay. The rate of cell apoptosis and cell cycle distribution were tested by flow cytometry. The cell morphology was observed with hoechst 33258 staining to analyze the correlation between EGFR mRNA expression and radiosensitivity of CRC cell lines.</p><p><b>RESULTS</b>A positive correlation between EGFR mRNA expression and survival fraction of 2 Gy(SF2) was observed (r=0.717, P=0.030). Association was also identified between the mutation status of PIK3CA and radiosensitivity (t=2.401, P=0.047), while mutation status of K-ras and B-raf was not associated with radiosensitivity. At 48-hour after exposing to irradiation, the apoptosis rate of radiosensitive cell line (HCT116) was significantly increased in a dose-dependent manner (P<0.05), while the apoptosis rate of radioresistant cell line (HT29) was significantly increased only when radiation dose increased to 6 Gy. The ratio of G0/G1 phase was reduced significantly with the increase of radiation dose in radiosensitive cell line (HCT116, P<0.05), while this trend was not observed in radioresistant cell line (HT29, P>0.05).</p><p><b>CONCLUSIONS</b>Over-expression of EGFR mRNA is correlated to radioresistance of human CRC cell lines, and mutation status of PIK3CA is closely related with radiosensitivity of CRC cells. The inhibition of apoptosis and G0/G1 arrest may induce the radioresistance of CRC cell lines.</p>

Colonoscopic restoration for sigmoid vovulus in the elderly / 中华胃肠外科杂志

<p><b>OBJECTIVE</b>To investigate the emergency therapeutic strategy for sigmoid vovulus in the elderly.</p><p><b>METHODS</b>Clinical data of 14 elderly patients with sigmoid vovulus were analyzed retrospectively.</p><p><b>RESULTS</b>The mean age was(79.1±7.2) years(range, 70-93), and 11 patients (78.6%) were male. Emergency decompression and restoration with colonoscopy was performed in all the patients with a success rate of 100%. No patient required emergent surgery. Four patients(28.6%) recurred and they were managed well by repeat colonoscopic restoration.</p><p><b>CONCLUSION</b>Emergency colonoscopic restoration is the first treatment of choice for sigmoid vovulus in the elderly because it is safe and effective, and can be performed repeatedly.</p>

Competing endogenous RNA regulation mechanism and its role in the development and progression of colorectal cancer / 中华胃肠外科杂志

MicroRNAs are negative regulators of mRNA, and latest studies show that "mRNAs can also inhibit microRNAs". With these reciprocal interactions, different mRNAs with identical "microRNA binding site" cim regulate each other by competitively binding to the same microRNA pool. This is the novel competing endogenous RNA (ceRN A)regulating mechanism. The ceRN A mechanism, which is a totally new regulating mechanism , greatly expands the regulatory network across genes. It has been proved by experimental evidence that, in HCT116 colon cancer cells,KRAS and PTEN , ZEB2 and PTEN can regulate each other by ceRNA mechanism.

Management of colorectal high-grade intraepithelial neoplasia based on colonoscopic biopsy / 中华胃肠外科杂志

<p><b>OBJECTIVE</b>To investigate the principle of management of colorectal high-grade intraepithelial neoplasia(HGIN) based on colonoscopic biopsy.</p><p><b>METHODS</b>Patients diagnosed as colorectal HGIN based on colonoscopic biopsy in the Changhai Hospital from January 2002 to December 2009 were enrolled in the study. The clinical data of all the patients were collected and analyzed. According to the subsequent operation, cases were divided into local complete resection group and radical operation group. The discrepancy between the biopsy diagnosis and postoperative diagnosis was investigated.</p><p><b>RESULTS</b>Of the 203 biopsy-based colorectal HGIN lesions, 156 underwent radical resection, while 47 received local complete resection. Univariate analyses indicated that tumors located in colon(P=0.02), tumors with sessile growth (P=0.00) and large tumors (P=0.00) were more likely to be treated with radical resection. Postoperative diagnosis revealed that 163 cases(80.3%) were invasive cancers, while the other 40 cases(19.7%) were HGIN lesions. Of the 156 cases resected radically, 140 cases were invasive cancers, 16 cases were diagnosed as HGIN. Of the 47 cases who underwent local complete resection, 24 cases were confirmed as HGIN but the other 23 cases were invasive cancers, in which 15 cases received subsequent radical operation.</p><p><b>CONCLUSIONS</b>A large proportion of biopsy-proven colorectal HGIN lesions are invasive cancers. Therefore, local resection should be performed to confirm diagnosis. For highly suspected malignant tumors which can not be removed completely by local resection, if anus can be reserved, a radical transabdominal surgery is recommended even without biopsy-proven malignancy in order to avoid treatment delay.</p>

Down regulation of multidrug resistance-associated protein 4 expression by RNA interference enhances radiosensitivity of colorectal carcinoma cell lines in vitro / 中华胃肠外科杂志

<p><b>OBJECTIVE</b>To investigate the effect of multidrug resistance-associated protein 4 (MRP4) expression on the radiosensitivity of colorectal carcinoma cell lines in vitro.</p><p><b>METHODS</b>The vector of shRNA for RNA interference was constructed and then transfected into HCT116 cell line to steadily down-regulate the expression of MRP4. HCT116 cells were divided into 3 groups including the CON group(non-transfected), NC group (negative control virus was added), and KD group (RNAi target was added for transfection). To test the effectiveness of RNA interference, real-time polymerase chain reaction and Western blot were used to measure the expression pattern of MRP4 at both mRNA and protein levels, respectively. For the examination of the effect of RNA interference of MRP4 on the radiosensitivity, flow cytometry was used to calculate the rate of apoptotic cells 24 h after 4 Gy radiation. Proliferation of the cells was measured via MTT assay at different time points.</p><p><b>RESULTS</b>ShRNA plasmid was successfully constructed. Transfection of this constructed vector into HCT116 cell line caused steady silencing of MRP4 expression (HCT116-KD). MRP4 mRNA and protein expression were significantly down-regulated following RNA interference(P<0.05). Twenty-four hours after radiation, the apoptosis rate of KD cell line was (71.7±0.8)%, significantly higher than that in the CON group [(56.1±0.9)%] and NC group[(59.8±0.8)%](P<0.05). Fourty-eight hours and 72 hours after radiation, the proliferation was significantly inhibited in KD cells compared to the control groups(P<0.05).</p><p><b>CONCLUSIONS</b>Expression of MRP4 is closely related to radio-tolerance of colorectal carcinoma. Down-regulation of MRP4 expression by RNA interference enhances radiosensitivity of colorectal carcinoma cell lines in vitro. MRP4 may be an effective molecular marker for predicting the radiosensitivity of colorectal carcinoma.</p>

Long non-coding RNA influences radiosensitivity of colorectal carcinoma cell lines by regulating cyclin D1 expression / 中华胃肠外科杂志

<p><b>OBJECTIVE</b>To screen long non-coding RNA which influences radiosensitivity of colorectal carcinoma cell lines and investigate the mechanism.</p><p><b>METHODS</b>Under different doses of radiation, colony formation assay and single-hit multi-target model were conducted to draw dose-survival curve and SF2 value of colorectal carcinoma cell lines(RKO, Lovo) was calculated. High-throughput lncRNA/mRNA chips were used to screen lncRNA genes and protein coding genes with expression differences more than 2 folds between RKO, Lovo cell lines and RKO cell line receiving 2Gy radiation. The main action pathway was computed by Gene Ontology analysis combined with Pathway analysis in order to explore the mechanism which induces the effect of lncRNA on radiosensitivity of colorectal carcinoma cell lines. Further experiment on P53, P21, cyclin D1 expression contents of RKO cell line was confirmed by real-time RT-PCR.</p><p><b>RESULTS</b>Lovo(SF2=0.47) was more sensitivity to radiation than RKO(SF2=0.53) according to the outcome of colony formation assay. High-throughput lncRNA/mRNA chips identified a total of 268 lncRNA genes and 270 protein coding genes. Gene Ontology analysis showed that the expression of genes associated with cell cycle process were significantly different (38.6%). There was a significant relationship between expression of several lncRNAs and CCND1 gene. Real-time RT-PCR showed no significant differences of P53 and P21 expression in RKO and Lovo cell lines(P>0.05), while cyclin D1 expression of RKO cell line was higher than that of Lovo cell lines(P<0.05). After exposed to 2 Gy doses of radiation, there was an obvious decrease of cyclin D1 expression in RKO cell lines(P<0.05), while P53 and P21 expressions were not different(P>0.05).</p><p><b>CONCLUSION</b>The possible mechanism is that lncRNAs compose transcription compound to combine with CCND1 gene and influence radiosensitivity of colorectal carcinoma cell lines by regulating expression of cyclin D1, which is independent of P53-P21-cyclin D1 pathway.</p>

Impacts of preoperative radiochemotherapy on operation and postoperative complications in patients with mid-low rectal carcinomas / 中华胃肠外科杂志

<p><b>OBJECTIVE</b>To investigate the impact of preoperative radiochemotherapy on postoperative complications in patients with mid-low rectal carcinomas.</p><p><b>METHODS</b>Clinicopathologic data of T3 and T4 patients with mid-low rectal carcinomas in the Department of Colorectal Surgery at the Changhai Hospital of The Second Military Medical University from January 2009 to December 2010 were analyzed retrospectively. This cohort included 81 patients treated with preoperative radiochemotherapy followed by operation(radiochemotherapy group) and 93 cases who underwent surgery alone(control group).</p><p><b>RESULTS</b>Both resection rate and sphincter preservation rate were higher in the radiochemotherapy group(100% and 86.4%) than those in the control group(94.6% and 73.1%), and the difference in sphincter preservation rate was statistically significant(P=0.039). There were no significant differences in the mean operative time [(130±15) min vs.(125±20) min, P>0.05] and mean amount of bleeding [(100±15) ml vs. (95±10) ml, P>0.05] between the two groups. The overall incidence of postoperative complications was similar(9.9% vs. 9.7%, P>0.05).</p><p><b>CONCLUSIONS</b>Preoperative radiochemotherapy can significantly increase sphincter preservation rate of mid-low rectal carcinomas, and does not increase the difficulty in surgical procedure and postoperative complications.</p>

Association of tumor budding with clinicopathological characteristics and prognosis in T2 rectal cancer / 中华胃肠外科杂志

<p><b>OBJECTIVE</b>To demonstrate the association of tumor budding with clinicopathological features and prognosis in T2 rectal cancer.</p><p><b>METHODS</b>Clinicopathological data of 123 patients who underwent potentially curative resection for T2 rectal carcinoma between 2001 and 2005 at the Changhai Hospital were collected. All pathology slides were stained with hematoxylin and eosin for microscopic examinations. The maximum value of tumor buds(MV) and average value of tumor buds(AV) were calculated, which were classified as low value (≤5), median value (5 < bud value < 10), and high value (≥10).</p><p><b>RESULTS</b>Univariate analysis and multivariate analysis revealed that MV(P=0.000), AV(P=0.001), and lymphatic invasion (P=0.006) were independent predictors for lymph node metastasis in T2 rectal cancer. Neural invasion and poorly differentiation were significantly associated with MV(P<0.05). Neural invasion, vascular invasion and poorly differentiation were were significantly associated to AV (P<0.01). Disease-free survival (DFS) of patients with low AV, median AV and high AV was 110.5 months, 95.8 months, and 60.0 months respectively. There were significance differences in DFS of low AV with median and high AV(P<0.05). DFS of patients with low MV, median MV and high MV was 115.1 months, 98.5 months, and 86.0 months respectively. There were significance differences in DFS between low and high AV, and median and high MV(P<0.01 and P<0.05), while no significant difference existed between low and median MV.</p><p><b>CONCLUSION</b>Tumor budding is a useful marker to indicate high invasiveness of rectal cancer and a valuable prognostic predictor.</p>

Surgical treatment of recurrent colorectal carcinoma in the elderly / 中华胃肠外科杂志

<p><b>OBJECTIVE</b>To evaluate the safety and efficacy of surgical treatment for recurrent colorectal carcinoma in the elderly.</p><p><b>METHODS</b>The clinical and follow up data of 24 elderly patients with recurrent colorectal carcinoma who were treated between January 2000 and June 2009 at the Changhai hospital of the Second Military Medical University were analyzed retrospectively.</p><p><b>RESULTS</b>Among the 24 patients there were 14 men and 10 women. The mean age of the patients was 76.9 ± 5.3 years. The local recurrence was found in 15 patients. In 9 patients, both distant metastases and local recurrence were found. A total of 24 patients received operation, including radical resection in 15 patients and palliative resection in 8 patients. One patient had laparotomy only because of diffuse metastases in the abdomen and involvement of the duodenum and common bile duct.The patient received stent placement in the common bile duct and chemotherapy after the surgery. Postoperative complication occurred in 7(29.2%) patients, which included ileus(n=1), pulmonary infection(n=1), urinary infection(n=1), wound infection(n=2), wound dehiscence(n=1), and wound fat liquefaction(n=1). There were no perioperative deaths. The median survival time was 6 months in the entire cohort. The median survival time was 33 months in patients undergoing radical resection, and the 1-, 3-, and 5-year survival rate was 71.4%, 28.6%, and 14.3%. The median survival time was 3 months in patients who underwent palliative resection, and the 1-year survival rate was 0. The difference between the two groups was statistically significant(P<0.01).</p><p><b>CONCLUSION</b>Outcomes are acceptable after radical resection for elderly patients with recurrent colorectal cancer if careful preoperative evaluation and perioperative management are performed.</p>

Preliminary study on relationship between multi-drug resistance-associated protein 4 and radiosensitivity of rectal cancer / 中华胃肠外科杂志

<p><b>OBJECTIVE</b>To explore the correlation between multi-drug resistance-associated protein 4(MRP4) and the sensitivity of rectal cancer to radiation.</p><p><b>METHODS</b>A total of 95 patients with advanced rectal cancer and received radiation therapy between January 2000 and January 2009. MRP4 and P53 protein expression in the paraffin-embedded specimen were detected by immunohistochemistry. Logistic regression analysis was used to evaluate factors associated with the sensitivity of rectal cancer to radiation.</p><p><b>RESULTS</b>Forty patients(42%) were sensitive to radiation therapy, of whom 10(11%) achieved pathological complete remission. Fifty-five patients were (58%) not responsive to radiation. Patients with low expression of MRP4 had a 66.7%(24/36) response rate, significantly higher than that of patients with high MRP4 expression (29.1%,16/59)(P<0.05). Patients with low expression of P53 had a 63.9%(23/36) response rate, significantly higher than that of patients with high P53 expression(28.8%,17/59)(P<0.01). The response rate after long course radiation therapy was 83.3%(20/24), significantly higher than that of patients who underwent short and medium course radiation[(31.3%, 5/16) and(27.3%,15/55)](P<0.01). Multivariate Logistic regression analysis showed radiation regimen, the expression of P53 and MRP4 protein were independently associated with the sensitivity of rectal cancer to radiation(P<0.05).</p><p><b>CONCLUSION</b>MRP4 may serve as a predictive marker for the sensitivity of rectal cancer to preoperative radiation.</p>

Computed tomography pelvimetry as a predictor of technical difficulty in total mesorectal excision / 中华胃肠外科杂志

<p><b>OBJECTIVE</b>To investigate the limiting effect of pelvic diameters on the technical difficulty of total mesorectal excision(TME) for rectal cancer by computed tomography pelvimetry.</p><p><b>METHODS</b>From January 2009 to January 2011, 69 patients with rectal cancer underwent TME in the Department of Proctology at the Changhai Hospital in Shanghai. There were 55 males and 14 females. Using three dimensional reconstruction software, pelvic dimensions of rectal cancer patients were measured based on pelvic MDCT thin-slice computed tomography. All the patients were measured for 15 pelvic parameters, including the length of pelvic inlet, the length of pubic symphysis, the interspinous distance, the distance from sacral promontory to tip of coccyx, etc. All the procedures were open surgery, including anterior resection(n=19), low anterior resection and ileostomy(n=29) and abdominal perineal resection(n=21). Duration of the operation and blood loss at surgery were recorded as evaluation indicators of the technical difficulty of total mesorectal excision. By univariate analysis significant pelvic parameters were selected. Multiple regression analysis was used to investigate the relationship between pelvic parameters and blood loss or duration of operation.</p><p><b>RESULTS</b>The mean operative time was(139.9±32.4) min and the mean intraoperative blood loss was (228.8±150.6) ml. Multivariate analysis showed that the interspinous distance, the length of pelvic inlet, the distance from sacral promontory to the tip of coccyx were the main factors affecting the operation time, and that the length of pubic symphysis and the distance from sacral promontory to the tip of coccyx were the main factors affecting the amount of blood loss (all P<0.05). Among the 3 procedures, the multivariate analysis for low anterior resection appeared to be most valuable, in which operative time was associated with the distance from sacral promontory to the tip of coccyx and the interspinous distance (adjusted coefficient of determination of the regression equation, Rc(2)=0.460, P=0.003). Factors associated with intraoperative blood loss were the length of pelvic inlet, the distance from sacral promontory to the tip of coccyx, and the sacrum-pubis angle(Rc(2)=0.358, P=0.022). Comprehensive analysis of the measurement parameters showed that the ratio between the length of pelvic inlet and the distance from sacral promontory to the tip of coccyx was associated with the operative time and blood loss. This ratio was significantly higher in female patients than that in males. In females with a ratio greater than 1, the operative time was significantly shorter(P=0.050), and the intraoperative blood loss was significantly less in males with a ratio greater than 0.9(P=0.021).</p><p><b>CONCLUSIONS</b>Operative time and intraoperative blood loss for total mesorectal excision are more favorable in patients with a wide and shadow pelvis. Surgical difficulty is increased in deep and narrow pelvis or those with major sacrum curvature. The difficulty of total mesorectal excision procedure can be predicted by measuring the length of pelvic inlet and the distance from sacral promontory to the tip of coccyx.</p>

Gene methylation in stool for the screening of colorectal cancer and pre-malignant lesions / 中华胃肠外科杂志

<p><b>OBJECTIVE</b>To evaluate association between DNA methylation of MAL, CDKN2A, and MGMT in stool and development of colorectal cancer, and to evaluate the screening value of these biomarkers in colorectal cancer and pre-malignant lesions.</p><p><b>METHODS</b>Morning stool specimens were collected from 69 patients with colorectal cancer, 24 with colon adenoma, 19 with hyperplastic polyps, and 26 healthy controls. DNA was extracted and treated with bisulfite. Methylation-specific PCR(MSP) was performed for methylation analysis of MAL, CDKN2A and MGMT in DNA samples. Associations between clinicopathological features and gene methylation were analyzed. The sensitivity of diagnosis by combining three methylation markers was compared with fecal occult blood test(FOBT).</p><p><b>RESULTS</b>The methylation frequencies of MAL, CDKN2A and MGMT were 78.3%, 52.5% and 55.1% in colorectal cancer, 58.3%, 41.7% and 37.5% in colon adenomas, 26.3%, 15.8% and 10.5% in hyperplastic polyps, and 3.8%, 0 and 3.8% in healthy controls, respectively. Significant differences in three genes were found between colorectal cancer and hyperplastic polyp, colorectal cancer and healthy control, colon adenoma and hyperplastic polyp, colon adenoma and healthy control(all P<0.05). The diagnostic sensitivity by combining three methylation markers was 92.8% in colorectal cancer, 70.8% in colon adenomas, significantly higher than FOBT examination (29.0% in colorectal cancer and 25.0% in colon adenomas, all P<0.05). No significant associations existed between three genes methylation of the three genes and clinical characteristic including sex, age, tumor location, lymph node metastases and TNM stage (all P>0.05).</p><p><b>CONCLUSION</b>DNA methylations levels of MAL, CDKN2A, and MGMT in stools are significantly higher in colorectal cancer and colon adenoma, which may serve as an noninvasive approach for the screening of colorectal cancer and pre-malignant lesions.</p>

Analysis of risk factors associated with lymph node metastasis and prognosis of T1-2 colorectal cancer / 中华胃肠外科杂志

<p><b>OBJECTIVE</b>To investigate factors associated with lymph node metastasis and prognosis in patients with T1-2 colorectal cancer.</p><p><b>METHODS</b>Patients with pT1-2 colorectal cancer between January 1999 to January 2005 were included. Chi-square test and multivariable logistic analysis were performed to evaluate risk factors associated with lymph node metastasis. Survival outcomes were analyzed using Kaplan-Meier and Cox regression model.</p><p><b>RESULTS</b>Tumor location and depth of invasion were independent risk factors for lymph node metastasis(P<0.01 and P<0.05). Gender, age, tumor gross pattern, tumor differentiation, carcinoembryonic antigen level, and tumor diameter were not associated with lymph node metastasis. Lymph node metastasis and distant metastasis on postoperative follow-up were independent risk factors for survival(P<0.05 and P<0.01).</p><p><b>CONCLUSION</b>Factors associated with lymph node metastasis in pT1-2 colorectal cancer do not affect the survival. However, lymph node metastasis and distant metastasis are predictive for survival.</p>

Lymph node metastasis and its risk factors in T1-2 staging invasive rectal carcinoma / 中华外科杂志

<p><b>OBJECTIVE</b>To investigate the lymph node metastasis and its risk factors in T1-2 staging invasive rectal carcinoma.</p><p><b>METHODS</b>The data of 1116 patients with rectal cancer treated with total mesorectal excision (TME) technique from January 2000 to April 2009 was analyzed retrospectively. The clinicopathological factors analyzed included gender, age, primary symptom type, number of symptoms, duration of symptom, synchronous polyps, preoperative serum carcino-embryonic antigen level, preoperative serum CA19-9 level, the distance of tumor from the anal verge, tumor size, tumor morphological type, tumor circumferential extent, tumor differentiation and tumor T staging. Statistical analysis was performed by using Logistic regression analysis and Chi-square test.</p><p><b>RESULTS</b>A total of 1116 patients were enrolled, and 358 cases (32.1%) were classified as with T1-2 staging tumor. Two cases (5.6%, 2/36) in patients with a T1 staging tumor were found with lymph node metastasis, and 75 cases (23.3%, 75/322) in patients with a T2 staging tumor, respectively. Compared with patients with T3-4 staging tumor, lymph node metastasis rate of the patients with T1-2 staging tumor was significantly lower [21.5% (77/358) vs. 51.6% (391/758), P < 0.05]. Only the tumor T staging was found as the independent risk factor for the lymph node metastasis in patients with T1-2 staging tumor on multivariate Logistic regression analysis (odds ratio: 5.162; 95%CI: 1.212 to 21.991; P = 0.026).</p><p><b>CONCLUSIONS</b>A substantial proportion of T1-2 staging rectal cancers harbor metastatic lymph nodes and the clinicopathological features except for T staging fail to predict the lymph node metastasis. Further research is warranted to identify the risk factors and guide the clinical practice in patient with T1-2 staging tumor.</p>

Effect of colonoscopy combined with placement of metallic clips on selecting colonic surgery incision / 中华胃肠外科杂志

<p><b>OBJECTIVE</b>To evaluate the accuracy and value of the placement of metallic clips during colonoscopy in the localization of colorectal cancer and incision selection.</p><p><b>METHODS</b>A total of 30 patients received metallic clip placement by colonoscopy before operation. Abdominal plain film (supine and upright position) was taken and incision was determined by the projection of clips on the abdominal wall.</p><p><b>RESULTS</b>The inaccuracy rate of localization by colonoscopy was 30%(9/30). Colonoscopy combined with the placement of metallic clips achieved an accurate incision rate of 100% (30/30).</p><p><b>CONCLUSIONS</b>There is a considerable rate of inaccuracy for localization in colonic cancer by colonoscopy. Colonoscopy combined with placement of metallic clips should be considered in order to select a reasonable incision.</p>

Accuracy comparison of preoperative histological assessment in differentiation and grading of rectal adenocarcinoma / 中华胃肠外科杂志

<p><b>OBJECTIVE</b>To compare the accuracy of preoperative assessment in differentiation and grading of rectal adenocarcinoma.</p><p><b>METHODS</b>One hundred consecutive patients diagnosed as invasive rectal cancer by colonoscopy biopsy and undergone operation in the Changhai Hospital from March 2006 to May 2008 were studied retrospectively. Patient characteristics, examination records, operative and pathologic reports were reviewed. The slides of preoperative biopsy and postoperative pathologic specimen were reviewed to identify the differentiation by a single pathologist. The results of preoperative biopsy were compared to those of postoperative specimen which was considered as final diagnosis. The accuracy of preoperative assessment of differentiation was calculated. Patients were then divided into two groups based on the preoperative differentiation:the low-grade tumor including well and moderately differentiated tumors, and the high-grade tumor consisting of poorly differentiated and undifferentiated tumors. The accuracy of grading was also calculated.</p><p><b>RESULTS</b>The accuracy of preoperative assessment of differentiation was 72%, with 20% overgrading and 8% undergrading, while the accuracy of preoperative grading was 91%, with 4% overgrading and 5% undergrading. The accuracy of grading was significantly higher than that of specific differentiation(P<0.01).</p><p><b>CONCLUSION</b>The grading of preoperative biopsy has high accuracy rate and should be considered in clinical practice.</p>

Integrity evaluation of resected mesentery specimen after total mesorectal excision by methylene blue perfusion via superior rectal artery / 中华胃肠外科杂志

<p><b>OBJECTIVE</b>To evaluate the integrity of the resected mesentery specimen after total mesorectal excision (TME) for low rectal cancer using methylene blue perfusion via the superior rectal artery.</p><p><b>METHODS</b>Twenty patients with low rectal cancer were randomly divided into the methylene blue group (n=10) and the control group (n=10). All the patients received TME and macroscopic examination of the mesorectal surface was performed to evaluate the quality of the surgical specimen. The methylene blue was injected into the specimen postoperatively via superior rectal artery.</p><p><b>RESULTS</b>The mesorectal surface of all the specimens was intact on macroscopic examination. However, after methylene blue perfusion, 2 specimens were found to be incomplete. The number of lymph nodes in the methylene blue group were significantly larger (17.3+/-2.4 vs 12.4+/-5.4, P=0.016).</p><p><b>CONCLUSIONS</b>Integrity evaluation of TME specimen is necessary. Methylene blue perfusion is a convenient and effective method to identify subtle incompleteness of specimen and can improve the detection of lymph node.</p>

Could tumor characteristics identified by colonoscopy predict the locally advanced rectal carcinoma? / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Neoadjuvant chemoradiation is now considered the standard care for locally advanced rectal carcinoma (T3-4 or/and N1-2 lesions), but the accuracy of staging examinations including endorectal ultrasonography (ERUS) and MRI is far from excellent. In addition, the above staging equipment or professionals who perform the examinations may not be available in some hospitals, while preoperative colonoscopy and biopsy are usually obtainable in most hospitals. The objective of the present study was to investigate the clinical and pathological characteristics of locally advanced rectal carcinoma and identify candidates for neoadjuvant chemoradiation.</p><p><b>METHODS</b>This was a retrospective study. Patients who were treated for rectal cancer at Changhai Hospital from January 1999 to July 2008 were identified from our prospectively collected database. Statistical analysis was performed using SPSS Software System (version 15.0). The Mann-Whitney test, chi-square test and multivariate Logistic regression analysis were performed.</p><p><b>RESULTS</b>A total of 1005 cases were included in this research, of which 761 cases were identified as locally advanced rectal carcinoma depending on postoperative TNM staging. The results of multivariate Logistic regression analysis indicated seven independent risk factors that could be used to predict a locally advanced rectal carcinoma independently: a high grade (including poor differentiation and undifferentiation) (OR: 3.856; 95% CI: 2.064 to 7.204; P = 0.000); large tumor size (OR: 2.455; 95% CI: 1.755 to 3.436; P = 0.000); elevated preoperative serum CEA level (OR: 1.823; 95% CI: 1.309 to 2.537; P = 0.000); non-polypoid tumor type (OR: 1.758; 95% CI: 1.273 to 2.427; P = 0.001); the absence of synchronous polyps (OR: 1.602; 95% CI: 1.103 to 2.327; P = 0.013); the absence of blood in stool (OR: 1.659; 95% CI: 1.049 to 2.624; P = 0.030); and a greater circumferential tumor extent (OR: 1.813; 95% CI: 1.055 to 3.113; P = 0.031). Based on these findings, a Logistic equation was established, the accuracy of which was 64% according to the information of the additional 50 cases.</p><p><b>CONCLUSIONS</b>Some independent risk factors related with locally advanced rectal carcinoma were identified, based on which it is possible to establish a Logistic equation as a tool to predict candidates of neoadjuvant chemoradiation. Further research about optimization of the equation is warranted.</p>