Restaging of locally advanced rectal cancer with magnetic resonance imaging and endoluminal ultrasound after preoperative chemoradiotherapy: a systemic review and meta-analysis.

BACKGROUND: Magnetic resonance imaging and endoluminal ultrasound play an important role in the restaging of locally advanced rectal cancer after preoperative chemoradiotherapy, yet their diagnostic accuracy is still controversial. OBJECTIVE: Meta-analysis was performed to estimate the diagnostic performance of MRI and endoluminal ultrasound. DATA SOURCES: Electronic databases from 1996 to March 2012 were searched. STUDY SELECTION AND INTERVENTIONS: Either MRI or endoluminal ultrasound was used to restage rectal cancer after chemoradiotherapy or radiation. MAIN OUTCOME MEASURES: T category, lymph node, and circumferential resection involvement were measured. RESULTS: The sensitivity estimate for rectal cancer diagnosis (T0) by endoluminal ultrasound (37.0%; 95% CI, 24.0%-52.1%) was higher (p = 0.04) than the sensitivity estimate for MRI (15.3%; 95% CI, 6.5%-32.0%). For T3-4 category, sensitivity estimates of MRI and endoluminal ultrasound were comparable, 82.1% and 87.6%, whereas specificity estimates were poor (53.5% and 66.4%). For lymph node involvement, there was no significant difference between the sensitivity estimates for MRI (61.8%) and endoluminal ultrasound (49.8%). Specificity estimates for MRI and endoluminal ultrasound were 72.0% and 78.7%. For circumferential resection margin involvement, MRI sensitivity and specificity were 85.4% and 80.0%. LIMITATIONS: To identify the heterogeneity, metaregression was performed on covariates. However, few of the covariates were identified to be statistically significant because of the lack of adequate original data. CONCLUSION: Accurate restaging of locally advanced rectal cancer by MRI and endoluminal ultrasound is still a challenge. Identifying T0 rectal cancer by imaging is not reliable. Before performing surgery, restaging is important, but some of the T0-2 patients are likely overestimated as T3-4. Both modalities for lymph node involvement are not very good. Magnetic resonance imaging may be a good method to reassess circumferential resection margin.

Comparison of short- and long-term outcomes after extralevator abdominoperineal excision and standard abdominoperineal excision for rectal cancer: a systematic review and meta-analysis.

PURPOSE: Whether the introduction of extralevator abdominoperineal excision (ELAPE) improves survival and safety remains controversial. We conducted a systematic review and meta-analysis of all comparative studies to define the efficacy and safety of ELAPE and standard abdominoperineal excision (APE). MATERIALS AND METHODS: A search for all major databases and relevant journals from inception to July 2013 without restriction on languages or regions was performed. Outcome measures were the oncological parameters of circumferential resection margin (CRM) involvement, intraoperative bowel perforation (IOP), and local recurrence, as well as other parameters of blood loss, operative time, length of hospitalization, and postoperative complication. The test of heterogeneity was performed with the Q statistic. RESULTS: A total of 949 patients were included in the meta-analysis. Oncological pooled estimates of intraoperative bowel perforation rate (RR 0.34; 95 % CI 0.21-0.54; P < 0.00001), CRM involvement (RR 0.44; 95 % CI 0.34-0.56; P < 0.00001), and local recurrence (RR 0.32; 95 % CI 0.14-0.74; P = 0.008) all showed outcomes that were significantly lower in ELAPE than in APE. A similar incidence of postoperative complication was attributed to both groups, including overall complication (RR 0.93; 95 % CI 0.66-1.32; P = 0.69), perineal wound complication (RR 0.72; 95 % CI 0.33-1.55; P = 0.39), and urinary dysfunction (RR 1.53; 95 % CI 0.88-2.67; P = 0.13). CONCLUSION: ELAPE has a lower intraoperative bowel perforation rate, positive CRM rate, and local recurrence rate than APE. There is evidence that in selected low rectal cancer patients, ELAPE is a more efficient and equally safe option to replace APE. Due to the inherent limitations of the present study, future randomized controlled trials will be useful to confirm this conclusion.

Lipopolysaccharide-induced failure of the gut barrier is site-specific and inhibitable by growth hormone.

BACKGROUND: Gut barrier failure caused by endotoxemia is a life-threatening problem. The present study aimed to determine whether any specific intestinal site is highly correlated with gut barrier failure, and whether recombinant human growth hormone (rhGH) can ameliorate gut barrier failure in a rat model of endotoxemia. METHODS: Enterostomy tubes were surgically placed in adult male Sprague-Dawley rats three days before induction of endotoxemia by lipopolysaccharide (LPS) injection. Controls received no LPS. Rats were then randomly assigned to receive subcutaneous injections of rhGH (experimental, n = 30) or 0.9 % saline (control, n = 15) at 24, 48, or 72 h after LPS injection. Escherichia coli labeled with green fluorescent protein (GFP) were injected into the intestinal segment of all rats through the enterostomy tubes. The number of GFP-labeled E. coli detected in mesenteric lymph nodes was examined after 96 h. Apoptosis and proliferation rates of intestinal epithelial cells, and intestinal permeability were measured. RESULTS: Endotoxemia led to high mortality, compared with the control group, and rhGH treatment did not improve survival. Intestinal permeability, reflected by translocation rates of GFP-labeled E. coli, and apoptosis rates in the LPS-induced endotoxemia group were higher than those in the non-endotoxemia control group, and the endotoxemia ileum group had the highest rates of both bacterial translocation and apoptosis. The LPS+GH group had less bacterial translocation and apoptosis than the LPS-induced endotoxemia group. In contrast, the proliferation rates were lower in the LPS group compared to the LPS+GH group. CONCLUSIONS: Endotoxemia can induce gut barrier failure in rats, and the ileum is the site of greatest risk. The GH can reduce the incidence of endotoxemia-induced gut barrier failure, but not the associated mortality.

A Substage Increase in The AJCC Classification System Improves Prognostic Prediction in Stage III Gastric Cancer With Insufficient Lymph Nodes Removed.

BACKGROUND: The impact of lymph nodes (LNs) removed on the survivals of patients with stage III gastric cancer, especially on that of those who undergo the adjuvant chemotherapy as a compensation for a possibly insufficient lymphadenectomy, is still unclear. METHODS: Consecutive patients (n = 488) with stage III gastric cancer under R0 curative resection followed by adjuvant chemotherapy were analyzed. The overall survival (OS) was compared between patients with insufficient LNs removed (ILNr, <16 LNs) and sufficient LNs removed (SLNr, ≥16 LNs). Performance of the prediction systems was evaluated using the Likelihood ratio χ2 test, Akaike information criterion (AIC), Harrell's concordance index (C-index), and area under the receiver operating characteristic curves (AUC). RESULTS: The OS of patients were significantly longer in those with SLNr relative to those with ILNr (for stage IIIA, 68.2 vs. 43.2 months, P = 0.042; for stage IIIB, 43.7 vs. 24.9 months, P < 0.001; for stage IIIC, 23.9 vs. 8.3 months, P < 0.001; and for total stage III, 37.7 vs. 21.7 months, P < 0.001). However, the OS were similar between stage IIIA patients with ILNr and stage IIIB patients with SLNr (P = 0.928), between IIIB patients with ILNr and IIIC patients with SLNr (P = 0.962), and IIIC patients with ILNr and stage IV (P = 0.668), respectively. A substage increase in the AJCC classification system, from IIIA to IIIB, from IIIB to IIIC, and from IIIC to IV in patients with ILNr, enhanced the accuracy of prognostic prediction in patients with stage III gastric cancer compared to the current TNM system (Likelihood ratio χ2, 188.6 vs. 184.8; AIC, 4336.4 vs. 4340.6; C-index, 0.695 vs. 0.679, P = 0.002). The ROC curves revealed that the performance of prognostic prediction was better in the new prediction system (AUC = 0.699) compared with the current TNM system (AUC = 0.676). CONCLUSIONS: ILNr (LNs <16) impairs the long-term outcomes of stage III gastric cancer underwent adjuvant chemotherapy. The status of LNs removal adds values to the current TNM system in prognostic prediction of stage III gastric cancer.

[Meta-analysis of safety and efficacy of self-expending metallic stents as bridge to surgery versus emergency surgery for left-sided malignant colorectal obstruction].

OBJECTIVE: To evaluate the safety and efficacy of self-expending metallic stents (SEMS) as bridge to surgery versus emergency surgery for left-sided malignant colorectal obstruction. METHODS: A comprehensive literature search of CENTRAL, PubMed, EMBASE, Medline, Ovid LWW, CMB, CNKI and Wanfang Databases were performed for all randomized controlled trials or retrospective studies comparing self-expending metallic stents as bridge to surgery(SABS group) with emergency surgery (ES group). A meta-analysis was carried out by RevMan5.1 software on the outcomes concerning safety and efficacy of the two groups. RESULTS: Fourteen studies matched the criteria including 1083 patients. Five were randomized controlled trials and nine were retrospective analysis. Compared with the ES group, the SABS group had a lower short-term mortality(RR=0.52, 95% CI:0.30-0.93, P<0.05), lower overall complications(RR=0.46, 95% CI:0.31-0.70, P<0.05), higher resection rate(RR=1.90, 95%CI:1.33-2.70, P<0.01), shorter operative time(MD=-59.77, 95%CI:-87.51--32.04, P<0.01), and shorter interval to first flatus(MD=-10.78, 95%CI:-16.67--4.90, P<0.01). There were no statistically significant differences between the two groups in permanent stomy and hospital stay. CONCLUSION: The safety and efficacy of self-expending metallic stents as bridge to surgery for left-sided malignant colorectal obstruction is superior to emergency surgery.