Xinming Song

Laparoscopic versus open adhesiolysis in patients with adhesive small bowel obstruction: a systematic review and meta-analysis

BACKGROUND The objective of this study was to evaluate whether surgical outcomes differ between laparoscopy versus the open approach for adhesive small bowel obstruction. METHODS PubMed, MEDLINE, Embase, and the Cochrane Library databases were electronically searched from 1985 to 2010. The study pooled the effects of outcomes of a total of 334 patients enrolled into 4 retrospective comparative studies using meta-analytic methods. RESULTS Laparoscopic adhesiolysis was associated with a reduced overall complication rate (odds ratio = .42, .25-.70, P < .01), prolonged ileus rate (odds ratio = .28, .10-.73, P = .01) and pulmonary complication rate (odds ratio = .20, .04-.94, P = .04) compared with the open approach. No significant differences were noted for intraoperative injury to bowel rates (odds ratio = 1.93, .76-4.89, P = .17), wound infection rates (odds ratio = .44, .17-1.12, P = .08), and mortality (odds ratio = .81, .12-5.49, P = .83). CONCLUSIONS Laparoscopic adhesiolysis is advantageous in most of the analyzed outcomes. Laparoscopic treatment of small bowel obstruction is recommended by experienced laparoscopic surgeons in selected patients.

miR-7 inhibits colorectal cancer cell proliferation and induces apoptosis by targeting XRCC2

Background Analysis using publicly available algorithms predicts that X-ray repair complementing defective repair in Chinese hamster cells 2 (XRCC2), a key component in the homologous recombination repair pathway, is a potential target of micro-ribonucleic acid-7 (miR-7). Some studies have shown that both miR-7 and XRCC2 are associated with cancer development. For this purpose, we searched for the possible relationship between miR-7 and XRCC2 in the development of colorectal cancer (CRC). Methods miR-7 expression was assessed in CRC specimens and cell lines using real-time polymerase chain reaction (PCR). Luciferase reporter assay was used to confirm the target associations. The effect of miR-7 on cell proliferation and apoptosis was confirmed in vitro by the methylthiazol tetrazolium (MTT) assay, colony formation assay, and flow cytometry. Gene and protein expression were examined using real time PCR and western blotting, respectively. Results miR-7 was downregulated in CRC specimens and cell lines, and targeted the 3′ untranslated region of XRCC2. miR-7 overexpression reduced cyclin D1 expression and increased p21, caspase-3, and BAX expression, which subsequently inhibited CRC cell proliferation and induced CRC cell apoptosis. However, XRCC2 can repress the inhibitory effects of miR-7 on proliferation. Conclusion Our findings suggest that miR-7 plays a protective role by inhibiting proliferation and increasing apoptosis of CRC cells. It may identify new targets for anti-cancer treatment.

Fecal calprotectin for evaluating postoperative recurrence of Crohn's disease: a meta-analysis of prospective studies.

Background:Fecal calprotectin (FC) levels have been extensively reported to correlate with clinical and endoscopic activities in Crohns disease (CD); however, the utility of FC levels in the postoperative setting remains to be determined. Using meta-analysis, we aimed to evaluate the utility of FC as a noninvasive marker of recurrence in patients with CD who had undergone previous surgical resection. Methods:An electronic search using keywords related to CD and FC was performed in multiple electronic resources from 1966 to March 2014. The extracted data were pooled using a hierarchical summary receiver operating curve model. Results:Ten articles met the inclusion criteria, and methodological quality was determined in detail for each study. The 10 studies presented FC levels in 613 postoperative CD patients. The pooled sensitivity and specificity values for assessing suspected endoscopic recurrence were 0.82 (95% confidence interval (CI), 0.73–0.89, 8 studies, n = 391) and 0.61 (95% CI, 0.51–0.71), respectively. The overall positive and negative likelihood ratios were 2.11 (95% CI, 1.68–2.66) and 0.29 (95% CI, 0.197–0.44), respectively. The pooled sensitivity and specificity values for evaluating clinical relapse were 0.59 (95% CI, 0.47–0.71; 3 studies, n = 183) and 0.88 (95% CI, 0.80–0.93), respectively. The overall positive and negative likelihood ratios were 5.10 and 0.47, respectively. Conclusions:As a simple and noninvasive marker, FC is useful in evaluating recurrence of postoperative patients with CD.

Clinical features and risk factors for primary surgery in 205 patients with Crohn's disease: analysis of a South China cohort.

BACKGROUND: The frequency of Crohns disease in China is increasing, but few reports are available on clinical features, phenotypes according to the Montreal classification, or risk factors for surgery in mainland China. OBJECTIVE: This study aimed to assess clinical presentation, phenotypes according to the Montreal classification, and potential risk factors for initial surgery in patients with Crohns disease in southern China. DESIGN: This was an observational study designed as a retrospective analysis of a historical cohort. SETTINGS: The study was conducted at a tertiary referral hospital, Guangzhou, China. PATIENTS: Medical records of 212 consecutive patients with Crohns disease were reviewed; data from 205 patients who met inclusion criteria were analyzed. MAIN OUTCOME MEASURES: The value of age, location, and behavior of disease according to the Montreal system, smoking behavior, and other clinical variables as potential risk factors in predicting the requirement for initial surgery was assessed by use of Cox regression analysis. RESULTS: A total of 205 patients were studied. Abdominal pain (181 patients, 88.3%) was the most common clinical presentation. At the time of diagnosis, age was between 17 and 40 years in 145 patients (70.7%). The Montreal classification of disease location was L3 (ileocolonic) in 114 patients (55.6%), disease behavior was classified as inflammatory in 133 patients (64.9%). During the course of their disease (median, 4 years; range, 1–21 years), 79 patients (38.5%) required bowel resection. Kaplan-Meier analysis showed that the overall cumulative rate of primary bowel surgery was 17.6% at 1 year after onset of symptoms, 20.3% at 2 years, 35.2% at 5 years, and 58.3% at 10 years. In our final Cox model, stricturing (HR, 3.67; 95% CI, 2.14–6.29; P < .001), penetrating behavior (HR, 4.60; 95% CI, 2.58–8.22; P < .001), and smoking habit (HR, 2.02; 95% CI, 1.15–3.53; P = .014) were significantly associated with an increased risk for bowel resection. LIMITATIONS: The study was limited by its retrospective nature. CONCLUSIONS: In Chinese patients with Crohns disease, abdominal pain is the most common clinical presentation, and the most common phenotypes are age 17 to 40 years at diagnosis, ileocolonic disease location, and inflammatory disease behavior. More than one-third of patients require surgery at a median of 4 years after onset of symptoms. Stricturing, penetrating disease, and smoking are associated with an increased risk of requiring bowel resection.

Pancreaticogastrostomy versus pancreaticojejunostomy after pancreaticoduodenectomy: A meta-analysis of randomized control trials

BACKGROUND Postoperative pancreatic fistula (PF) is the leading morbidity after pancreaticoduodenectomy (PD). The pancreatoenteric anastomosis method after PD is associated with the occurrence of PF. Evidence shows that pancreaticogastrostomy (PG) is possibly superior to pancreaticojejunostomy (PJ) in reducing the incidence of PF after PD; however, this remains to be definitively confirmed. METHODS Randomized clinical trials (RCTs) comparing the outcomes of PG versus PJ after PD were retrieved for meta-analysis. RESULTS After a thorough search of the English literature published until March 23rd, 2014, we identified seven RCTs involving 1095 patients (PG group, 548; PJ group, 547) for final analysis. Meta-analysis revealed that the incidence of PF was significantly lower in the PG group (15.7%) than in the PJ group (23.0%, 126/547; OR = 0.61, 95% CI: 0.45-0.83, P = 0.002). Furthermore, the incidence of intra-abdominal fluid collection was also lower in the PG group than in the PJ group (OR = 0.43, 95% CI: 0.28-0.65, P < 0.0001). No significant differences were found between the PG and PJ groups in terms of delayed gastric emptying, hemorrhage, overall morbidity and mortality. CONCLUSIONS PG seemed to be superior to PJ in reducing the incidence of PF and intra-abdominal fluid collection after PD.

Does Preoperative Radio(chemo)therapy Increase Anastomotic Leakage in Rectal Cancer Surgery? A Meta-Analysis of Randomized Controlled Trials

Objective. Preoperative radio(chemo)therapy (pR(C)T) appears to increase postoperative complications of rectal cancer resection, but clinical trials have reported conflicting results. The objective of this meta-analysis was performed to assess the effects of pR(C)T on anastomotic leak after rectal cancer resection. Methods. PubMed, Embase, and the Cochrane Library were searched from January 1980 to January 2014. Randomized controlled trials included all original articles reporting anastomotic leak in patients with rectal cancer, among whom some received preoperative radiotherapy or chemoradiotherapy while others did not. The analysed end-points were the anastomotic leak. Result. Seven randomized controlled trials with 3375 patients were included in the meta-analysis. 1660 forming the group undergoing preoperative radiotherapy or chemoradiotherapy versus 1715 patients undergoing without preoperative radiotherapy or chemoradiotherapy. The meta-analyses found that pR(C)T was not an independent risk factor for anastomotic leakage (OR 1.02, 95% CI 0.80–1.30; P = 0.88). Subgroups analysis was performed and the result was not altered. Conclusions. Current evidence demonstrates that pR(C)T did not increase the risk of postoperative anastomotic leak after rectal cancer resection in patients.

Use of absorbable hemostatic gauze with medical adhesive is effective for achieving hemostasis in presacral hemorrhage

BACKGROUND Management of presacral hemorrhage is always challenging. Herein we describe the use of an absorbable hemostatic gauze with α-cyanoacrylate medical adhesive to achieve hemostasis. METHODS In this study, we conducted total mesorectal excision for the treatment of rectal cancer in 258 patients from March 2006 to May 2009. Intraoperative presacral hemorrhage developed in 5 (2%) patients during rectal mobilization. RESULTS In these 5 patients, massive bleeding could not be controlled by pressure and pelvic packing with gauze. An absorbable hemostatic gauze spread with medical adhesive was compressed onto the bleeding vessel for at least 20 minutes. Hemostasis was achieved successfully and was maintained during the surgery. Patients recovered uneventfully and no postoperative events were noted. CONCLUSIONS The use of an absorbable hemostatic gauze with medical adhesive is a simple and effective method for achieving hemostasis when massive presacral hemorrhage occurs. However, its effectiveness needs to be confirmed in a controlled study in a properly selected patient population.

Risk factors for adverse outcome in low rectal cancer

AIM To demonstrate the oncologic outcomes of low rectal cancer and to clarify the risk factors for survival, focusing particularly on the type of surgery performed. METHODS Data from patients with low rectal carcinomas who underwent surgery, either sphincter-preserving surgery (SPS) or abdominoperineal resection (APR), at The First Affiliated Hospital of Sun Yat-sen University in China from August 1994 to December 2005 were retrospectively analyzed. RESULTS Of 331 patients with low rectal cancer, 159 (48.0%) were treated with SPS. A higher incidence of positive resection margins and a higher 5-year cumulative local recurrence rate (14.7% vs 6.8%, P = 0.041) were observed in patients after APR compared to SPS. The five-year overall survival (OS) was 54.6% after APR and 66.8% after SPS (P = 0.018), and the 5-year disease-free survival (DFS) was 52.9% after APR and 65.5% after SPS (P = 0.013). In multivariate analysis, poor OS and DFS were significantly related to positive resection margins, pT3-4, and pTNM III-IV but not to the type of surgery. CONCLUSION Despite a higher rate of positive resection margins after APR, the type of surgery was not identified as an independent risk factor for survival.

Combined olaparib and oxaliplatin inhibits tumor proliferation and induces G2/M arrest and γ-H2AX foci formation in colorectal cancer

Background Poly (ADP-ribose) polymerase 1 (PARP1) has an important role in homologous recombination repair. The purpose of this study was to investigate the effect of PARP1 inhibitor on oxaliplatin treatment for colorectal cancer (CRC). Methods A cell counting kit-8 assay was used to determine the sensitivity of CRC cells to olaparib and/or oxaliplatin. The gene and protein expressions of PARP1 and the gamma histone variant H2AX (γH2AX) were measured by real-time quantitative polymerase chain reaction and western blotting, respectively. The γH2AX foci formation assay was used to investigate the influence of treatments on cells. Flow cytometry was used to examine the changes in cell cycle distribution. Finally, we investigated the combination of olaparib and oxaliplatin in the CRC tumor model. Results Olaparib changed the expression of γH2AX and PARP1, and increased the sensitivity of CRC cells to oxaliplatin. The γH2AX foci assay showed that olaparib did not induce double-strand breaks (DSBs) alone, but it enhanced the induction of DSBs by oxaliplatin. The flow cytometry results showed that cells exposed to combination treatment had more G2/M-phase cells than control. Additionally, tumor xenograft studies suggested that combined treatment inhibited the growth of CRC. Conclusion CRC cells are sensitized to combined treatment with olaparib and oxaliplatin, and this could be a promising strategy for clinical chemotherapy in CRC.

XRCC2 Promotes Colorectal Cancer Cell Growth, Regulates Cell Cycle Progression, and Apoptosis

AbstractX-ray repair complementing defective repair in Chinese hamster cells 2 (XRCC2) and poly(ADP-ribose) polymerase 1 (PARP1) both play important roles in homologous recombination DNA repair. According to the theory of synthetic lethality, XRCC2-deficient cells are more sensitive to PARP1 inhibitors compared to XRCC2-expressing cells. We investigated XRCC2 expression and function in colorectal cancer (CRC), and the characteristics of sensitivity to PARP1 inhibitor in CRC cells with different XRCC2 levels.We enrolled 153 patients with CRC who had undergone surgery in this study. XRCC2 expression was assessed using immunohistochemistry. Stable CRC SW480 cell lines with low or high XRCC2 expression were constructed. Following treatment with the PARP1 inhibitor olaparib, the viability of cells with different XRCC2 levels was determined; cell cycle distribution and apoptosis were analyzed using flow cytometry. B-cell lymphoma-2 (Bcl-2) protein expression was measured by Western blotting.The positive rates of XRCC2 in primary CRC tissue were significantly higher than that in the matched adjacent noncancerous tissue, and XRCC2 expression status in primary CRC was related to tumor site, Dukes’ stage, and tumor-nodes-metastasis (TNM) stage. XRCC2 overexpression inhibited CRC cell apoptosis and promoted proliferation by enriching cells in the G0/G1 phase. Moreover, olaparib suppressed proliferation, and olaparib sensitivity in CRC cells with high XRCC2 expression was greater.High XRCC2 expression promotes CRC cell proliferation and enriches cells in the G0/G1 phase but inhibits apoptosis. High XRCC2 expression cells are more sensitive to olaparib, which inhibits their viability.