A meta-analysis comparing the risk of metastases in patients with rectal cancer and MRI-detected extramural vascular invasion (mrEMVI) vs mrEMVI-negative cases.

BACKGROUND: Pathological extramural vascular invasion (EMVI) is an independent prognostic factor in rectal cancer, but can also be identified on MRI-detected extramural vascular invasion (mrEMVI). We perform a meta-analysis to determine the risk of metastatic disease at presentation and after surgery in mrEMVI-positive patients compared with negative tumours. METHODS: Electronic databases were searched from January 1980 to March 2016. Conventional meta-analytical techniques were used to provide a summative outcome. Quality assessment of the studies was performed. RESULTS: Six articles reported on mrEMVI in 1262 patients. There were 403 patients in the mrEMVI-positive group and 859 patients in the mrEMVI-negative group. The combined prevalence of mrEMVI-positive tumours was 0.346(range=0.198-0.574). Patients with mrEMVI-positive tumours presented more frequently with metastases compared to mrEMVI-negative tumours (fixed effects model: odds ratio (OR)=5.68, 95% confidence interval (CI) (3.75, 8.61), z=8.21, df=2, P<0.001). Patients who were mrEMVI-positive developed metastases more frequently during follow-up (random effects model: OR=3.91, 95% CI (2.61, 5.86), z=6.63, df=5, P<0.001). CONCLUSIONS: MRI-detected extramural vascular invasion is prevalent in one-third of patients with rectal cancer. MRI-detected extramural vascular invasion is a poor prognostic factor as evidenced by the five-fold increased rate of synchronous metastases, and almost four-fold ongoing risk of developing metastases in follow-up after surgery.

A diagnostic accuracy meta-analysis of endoanal ultrasound and MRI for perianal fistula assessment.

BACKGROUND: Imaging modalities such as endoanal ultrasound or MRI can be useful preoperative adjuncts before the appropriate surgical intervention for perianal fistulas. OBJECTIVES: We present a systematic review of published literature comparing endoanal ultrasound with MRI for the assessment of idiopathic and Crohn's perianal fistulas. DESIGN: A meta-analysis was performed to obtain pooled values for specificity and sensitivity. SETTINGS: Electronic databases were searched from January 1970 to October 2010 for published studies. PATIENTS AND INTERVENTIONS: Four studies were used in our analysis. There were 241 fistulas in the ultrasound group and 240 in the magnetic resonance group. RESULTS: The combined sensitivity and specificity of magnetic resonance for fistula detection were 0.87 (95% CI: 0.63-0.96) and 0.69 (95% CI: 0.51-0.82). There was a high degree of heterogeneity between studies reporting on MRI sensitivity (df = 3, I = 93%). This compares to a sensitivity and specificity for endoanal ultrasound of 0.87 (95% CI: 0.70-0.95) and 0.43 (95% CI: 0.21-0.69). There was a high degree of heterogeneity between studies reporting on endoanal ultrasound sensitivity (df = 3, I = 92%). CONCLUSIONS: From the available literature, the summarized performance characteristics for MRI and endoanal ultrasound demonstrate comparable sensitivities at detecting perianal fistulas, although the specificity for MRI was higher than that for endoanal ultrasound. Both specificity values are considered to be diagnostically poor, however. The high degree of data heterogeneity and the shortage of applicable studies precludes any firm conclusions being made for clinical practice. Future trials with improved study design (including prospective data collection and consideration of verification bias) may help to further clarify the role of MRI in the assessment and treatment response monitoring of perianal fistulas (particularly in patients with Crohn's disease).

Elective open versus laparoscopic sigmoid colectomy for diverticular disease: a meta-analysis with the Sigma trial.

BACKGROUND: A meta-analysis of published literature comparing open versus laparoscopic elective sigmoid resections for diverticular disease was conducted. METHODS: Electronic databases were searched for data from January 1991 to March 2009. A systematic review was performed to obtain a summative outcome. RESULTS: Twenty-two comparative studies involving 10,898 patients were analyzed; 1538 patients were in the laparoscopic group and 9360 were in the open group. The operative time for laparoscopic sigmoid resection (LSR) is longer than open resections (OSR) [random-effects model: SMD = 1.94, 95% CI = (1.14, 2.74), z = 4.74, p < 0.001]. However, patients who undergo LSR have earlier return to passage of feces [random-effects model: SMD = -1.01, 95% CI (-1.80, -0.22), z = -2.50, p = 0.013] and shorter hospital stay [random-effects model: SMD = -7.65, 95% CI (-10.96, -4.32), z = -4.52, p < 0.001]. Overall morbidity was higher in the OSR group [random-effects model: RR = 0.56, 95% CI (0.40, 0.80), z = -3.24, p < 0.001] and no difference in mortality rates was observed (p = 0.81). CONCLUSIONS: Laparoscopic sigmoid resection takes longer to perform than open procedures; however, it is safe and has lower overall morbidity, earlier return of bowel function, and shorter hospital stays. This approach should be considered for elective cases but more randomized controlled trials are required to strengthen the evidence.

FDG PET/CT Can Assess the Response of Locally Advanced Rectal Cancer to Neoadjuvant Chemoradiotherapy: Evidence From Meta-analysis and Systematic Review.

INTRODUCTION: Neoadjuvant chemoradiotherapy (CRT) is indicated in locally advanced rectal adenocarcinoma where there is a high risk of local recurrence based on preoperative imaging. Optimal radiological assessment of CRT response is unknown, and metabolic assessment of the tumor has been suggested to gauge response before surgical resection. PATIENTS AND METHODS: A systematic search of the MEDLINE database was performed using the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) statement to identify papers comparing pre- and post-CRT PET/CT in patients with locally advanced rectal adenocarcinoma with histopathological assessment of tumor regression. Papers were assessed with the QUADAS (Quality Assessment of Diagnostic Accuracy Studies) tool. Meta-analysis was performed for response index (RI) and SUVmax post-CRT. RESULTS: Ten of 69 studies met inclusion criteria containing a total of 538 patients. Methodological quality was high with low heterogeneity. In all studies, post-CRT PET/CT showed a reduction in SUVmax and the RI irrespective of histological findings. Tumors confirmed to have regressed after CRT had a mean difference of 12.21% higher RI (95% confidence interval, 6.51-17.91; P < 0.00001) compared with nonresponders. Mean difference between pre- and post-CRT SUVmax groups was -2.48 (95% confidence interval, -3.06 to -1.89; P < 0.00001) with histopathological responders having a lower post-CRT SUVmax. CONCLUSIONS: The available evidence suggests that PET/CT may be a useful addition to the current imaging modalities in the assessment of treatment response.

Systematic review of prognostic importance of extramural venous invasion in rectal cancer.

AIM: To systematically review the survival outcomes relating to extramural venous invasion in rectal cancer. METHODS: A systematic review was conducted using PRISMA guidelines. An electronic search was carried out using MEDLINE, EMBASE, CINAHL, Cochrane library databases, Google scholar and PubMed until October 2014. Search terms were used in combination to yield articles on extramural venous invasion in rectal cancer. Outcome measures included prevalence and 5-year survival rates. These were graphically displayed using Forest plots. Statistical analysis of the data was carried out. RESULTS: Fourteen studies reported the prevalence of extramural venous invasion (EMVI) positive patients. Prevalence ranged from 9%-61%. The pooled prevalence of EMVI positivity was 26% [Random effects: Event rate 0.26 (0.18, 0.36)]. Most studies showed that EMVI related to worse oncological outcomes. The pooled overall survival was 39.5% [Random effects: Event rate 0.395 (0.29, 0.51)]. CONCLUSION: Historically, there has been huge variation in the prevalence of EMVI through inconsistent reporting. However the presence of EMVI clearly leads to worse survival outcomes. As detection rates become more consistent, EMVI may be considered as part of risk-stratification in rectal cancer. Standardised histopathological definitions and the use of magnetic resonance imaging to identify EMVI will improve detection rates in the future.

Defining response to radiotherapy in rectal cancer using magnetic resonance imaging and histopathological scales.

AIM: To define good and poor regression using pathology and magnetic resonance imaging (MRI) regression scales after neo-adjuvant chemotherapy for rectal cancer. METHODS: A systematic review was performed on all studies up to December 2015, without language restriction, that were identified from MEDLINE, Cochrane Controlled Trials Register (1960-2015), and EMBASE (1991-2015). Searches were performed of article bibliographies and conference abstracts. MeSH and text words used included "tumour regression", "mrTRG", "poor response" and "colorectal cancers". Clinical studies using either MRI or histopathological tumour regression grade (TRG) scales to define good and poor responders were included in relation to outcomes [local recurrence (LR), distant recurrence (DR), disease-free survival (DFS), and overall survival (OS)]. There was no age restriction or stage of cancer restriction for patient inclusion. Data were extracted by two authors working independently and using pre-defined outcome measures. RESULTS: Quantitative data (prevalence) were extracted and analysed according to meta-analytical techniques using comprehensive meta-analysis. Qualitative data (LR, DR, DFS and OS) were presented as ranges. The overall proportion of poor responders after neo-adjuvant chemo-radiotherapy (CRT) was 37.7% (95%CI: 30.1-45.8). There were 19 different reported histopathological scales and one MRI regression scale (mrTRG). Clinical studies used nine and six histopathological scales for poor and good responders, respectively. All studies using MRI to define good and poor response used one scale. The most common histopathological definition for good response was the Mandard grades 1 and 2 or Dworak grades 3 and 4; Mandard 3, 4 and 5 and Dworak 0, 1 and 2 were used for poor response. For histopathological grades, the 5-year outcomes for poor responders were LR 3.4%-4.3%, DR 14.3%-20.3%, DFS 61.7%-68.1% and OS 60.7-69.1. Good pathological response 5-year outcomes were LR 0%-1.8%, DR 0%-11.6%, DFS 78.4%-86.7%, and OS 77.4%-88.2%. A poor response on MRI (mrTRG 4,5) resulted in 5-year LR 4%-29%, DR 9%, DFS 31%-59% and OS 27%-68%. The 5-year outcomes with a good response on MRI (mrTRG 1,2 and 3) were LR 1%-14%, DR 3%, DFS 64%-83% and OS 72%-90%. CONCLUSION: For histopathology regression assessment, Mandard 1, 2/Dworak 3, 4 should be used for good response and Mandard 3, 4, 5/Dworak 0, 1, 2 for poor response. MRI indicates good and poor response by mrTRG1-3 and mrTRG4-5, respectively.

Systematic review of emergent laparoscopic colorectal surgery for benign and malignant disease.

Laparoscopic surgery has become well established in the management of both and malignant colorectal disease. The last decade has seen increasing numbers of surgeons trained to a high standard in minimally-invasive surgery. However there has not been the same enthusiasm for the use of laparoscopy in emergency colorectal surgery. There is a perception that emergent surgery is technically more difficult and may lead to worse outcomes. The present review aims to provide a comprehensive and critical appraisal of the available literature on the use of laparoscopic colorectal surgery (LCS) in the emergency setting. The literature is broadly divided by the underlying pathology; that is, inflammatory bowel disease, diverticulitis and malignant obstruction. There were no randomized trials and the majority of the studies were case-matched series or comparative studies. The overall trend was that LCS is associated with shorter hospital stay, par or fewer complications but an increased operating time.Emergency LCS can be safely undertaken for both benign and malignant disease providing there is appropriate patient selection, the surgeon is adequately experienced and there are sufficient resources to allow for a potentially more complex operation.

Randomised controlled trials in plastic surgery: a systematic review of reporting quality.

BACKGROUND: We recently conducted a systematic review of the methodological quality of randomised controlled trials (RCTs) in plastic surgery. In accordance with convention, we are here separately reporting a systematic review of the reporting quality of the same RCTs. METHODS: MEDLINE® and the Cochrane Database of Systematic Reviews were searched by an information specialist from 1 January 2009 to 30 June 2011 for the MESH heading 'Surgery, Plastic'. Limitations were entered for English language, human studies and randomised controlled trials. Manual searching for RCTs involving surgical techniques was performed within the results. Scoring of the eligible papers was performed against the 23-item CONSORT Statement checklist. Independent secondary scoring was then performed and discrepancies resolved through consensus. RESULTS: Fifty-seven papers met the inclusion criteria. The median CONSORT score was 11.5 out of 23 items (range 5.3-21.0). Items where compliance was poorest included intervention/comparator details (7 %), randomisation implementation (11 %) and blinding (26 %). Journal 2010 impact factor or number of authors did not significantly correlate with CONSORT score (Spearman rho = 0.25 and 0.12, respectively). Only 61 % declared conflicts of interest, 75 % permission from an ethics review committee, 47 % declared sources of funding and 16 % stated a trial registry number. There was no correlation between the volume of RCTs performed in a particular country and reporting quality. CONCLUSIONS: The reporting quality of RCTs in plastic surgery needs improvement. Better education, awareness amongst all stakeholders and hard-wiring compliance through electronic journal submission systems could be the way forward. We call for the international plastic surgical community to work together on these long-standing problems.