Predictive score for anastomotic leakage after elective colorectal cancer surgery: a decision making tool for choice of protective measures

Development of a Clinical Framework-Anastomotic Leakage Prediction Score (CF-ALPS) After Colorectal Surgery

Background: Anastomotic leakage (AL) is a severe complication of colorectal surgery and is associated with high morbidity, mortality, and prolonged hospital stay. Current predictive models vary in complexity and utility, highlighting the need for clinically accessible and accurate tools. This study aimed to develop and validate the clinical framework-anastomotic leakage prediction score (CF-ALPS) score, a practical and accessible risk prediction model for AL that integrates patient-, tumor-, and surgery-related factors. Methods: A retrospective cohort of 294 patients who underwent colorectal surgery between 2019 and 2024 was analyzed. Patients were categorized into the AL (n = 84) and non-AL groups (n = 210). The factors included age, sex, hypoalbuminemia, and comorbidities. Tumor-related factors included lymph node stage and neoadjuvant therapy, while surgical variables included urgency, duration, and type of procedure. The outcomes evaluated were the incidence of AL, duration of hospital stay, and in-hospital mortality. Independent predictors were identified using multivariate logistic regression analysis. The CF-ALPS score, which was developed from significant predictors, was validated using ROC curve analysis and 10-fold cross-validation. Results: A total of 294 patients who underwent colorectal surgery were included, of whom 84 (28.57%) developed AL. A male predominance was observed in the AL group (73.81% vs. 36.19%; p = 0.001). Nutritional status played a critical role, with significantly lower albumin levels in AL patients (2.8 ± 0.5 g/dL vs. 3.5 ± 0.4 g/dL; p < 0.001). Independent predictors of AL included hypoalbuminemia (<3.0 g/dL, OR: 0.52, p < 0.001), ASA score (OR, 1.85; p = 0.004), advanced lymph node stage (N2/N3, OR: 1.94, p = 0.037), neoadjuvant therapy (OR, 2.89; p = 0.002), and emergent surgery (OR, 1.67; p = 0.042). These variables formed the basis of the CF-ALPS score, which assigns weighted points based on the magnitude of their ORs. The CF-ALPS model achieved a ROC AUC of 0.82 (95% CI: 0.75-0.89) with a sensitivity of 85.0% and specificity of 78.0%. A cutoff score ≥7 demonstrated optimal risk stratification, classifying patients into high- and low-risk groups with a positive predictive value (PPV) of 72.0% and a negative predictive value (NPV) of 88.0%. Cross-validation yielded a moderate AUC of 0.44 (SD = 0.062). Conclusions: The CF-ALPS score offers a simple and effective tool for AL risk prediction in colorectal surgery, emphasizing its practicality and clinical integration. Although its predictive accuracy was moderate, further prospective multicenter validation is warranted.

When Is Diversion Indicated After Right-Sided Colon Resections?

INTRODUCTION

Ileocolonic anastomoses have a low anastomotic leak (AL) risk, resulting in infrequent diverting loop ileostomy use. Identifying patients who warrant diverting loop ileostomy with right-sided resection is challenging due to this low incidence of AL. Therefore, a multicenter database was used to develop an AL risk score to help inform when diversion should be strongly considered after right-sided resections.

MATERIALS AND METHODS

Patients undergoing elective right-sided resections within the 2012-2020 American College of Surgeons National Surgical Quality Improvement Program-targeted colectomy participant user files were identified. Multivariable logistic regression identified AL risk factors that were then converted to point values to develop an AL risk score. The developed AL risk score was then assessed for visual correspondence and analyzed for internal validity.

RESULTS

42,176 patients underwent right-sided resection without diversion, and the incidence of AL was 2.4%. The risk calculator exhibited excellent calibration and fair discrimination. Strong visual correspondence was observed for predicted and actual AL rates within the 95% confidence interval for nine of ten risk score deciles.

CONCLUSIONS

An internally validated AL risk score for elective ileocolic resections was developed. Most patients had scores that categorized them at a low risk of AL. The diversion after elective right-sided resections should be reserved for extreme cases.

Machine learning-based preoperative analytics for the prediction of anastomotic leakage in colorectal surgery: a swiss pilot study

BACKGROUND

Anastomotic leakage (AL), a severe complication following colorectal surgery, arises from defects at the anastomosis site. This study evaluates the feasibility of predicting AL using machine learning (ML) algorithms based on preoperative data.

METHODS

We retrospectively analyzed data including 21 predictors from patients undergoing colorectal surgery with bowel anastomosis at four Swiss hospitals. Several ML algorithms were applied for binary classification into AL or non-AL groups, utilizing a five-fold cross-validation strategy with a 90% training and 10% validation split. Additionally, a holdout test set from an external hospital was employed to assess the models' robustness in external validation.

RESULTS

Among 1244 patients, 112 (9.0%) suffered from AL. The Random Forest model showed an AUC-ROC of 0.78 (SD: ± 0.01) on the internal test set, which significantly decreased to 0.60 (SD: ± 0.05) on the external holdout test set comprising 198 patients, including 7 (3.5%) with AL. Conversely, the Logistic Regression model demonstrated more consistent AUC-ROC values of 0.69 (SD: ± 0.01) on the internal set and 0.61 (SD: ± 0.05) on the external set. Accuracy measures for Random Forest were 0.82 (SD: ± 0.04) internally and 0.87 (SD: ± 0.08) externally, while Logistic Regression achieved accuracies of 0.81 (SD: ± 0.10) and 0.88 (SD: ± 0.15). F1 Scores for Random Forest moved from 0.58 (SD: ± 0.03) internally to 0.51 (SD: ± 0.03) externally, with Logistic Regression maintaining more stable scores of 0.53 (SD: ± 0.04) and 0.51 (SD: ± 0.02).

CONCLUSION

In this pilot study, we evaluated ML-based prediction models for AL post-colorectal surgery and identified ten patient-related risk factors associated with AL. Highlighting the need for multicenter data, external validation, and larger sample sizes, our findings emphasize the potential of ML in enhancing surgical outcomes and inform future development of a web-based application for broader clinical use.

Score prediction of anastomotic leak in colorectal surgery: a systematic review

OBJECTIVE

Predicting the risk of anastomotic leak (AL) is of importance when defining the optimal surgical strategy in colorectal surgery. Our objective was to perform a systematic review of existing scores in the field.

METHODS

We followed the PRISMA checklist (S1 Checklist). Medline, Cochrane Central and Embase were searched for observational studies reporting on scores predicting AL after the creation of a colorectal anastomosis. Studies reporting only validation of existing scores and/or scores based on post-operative variables were excluded. PRISMA 2020 recommendations were followed. Qualitative analysis was performed.

RESULTS

Eight hundred articles were identified. Seven hundred and ninety-one articles were excluded after title/abstract and full-text screening, leaving nine studies for analysis. Scores notably included the Colon Leakage Score, the modified Colon Leakage Score, the REAL score, www.anastomoticleak.com and the PROCOLE score. Four studies (44.4%) included more than 1.000 patients and one extracted data from existing studies (meta-analysis of risk factors). Scores included the following pre-operative variables: age (44.4%), sex (77.8%), ASA score (66.6%), BMI (33.3%), diabetes (22.2%), respiratory comorbidity (22.2%), cardiovascular comorbidity (11.1%), liver comorbidity (11.1%), weight loss (11.1%), smoking (33.3%), alcohol consumption (33.3%), steroid consumption (33.3%), neo-adjuvant treatment (44.9%), anticoagulation (11.1%), hematocrit concentration (22.2%), total proteins concentration (11.1%), white blood cell count (11.1%), albumin concentration (11.1%), distance from the anal verge (77.8%), number of hospital beds (11.1%), pre-operative bowel preparation (11.1%) and indication for surgery (11.1%). Scores included the following peri-operative variables: emergency surgery (22.2%), surgical approach (22.2%), duration of surgery (66.6%), blood loss/transfusion (55.6%), additional procedure (33.3%), operative complication (22.2%), wound contamination class (1.11%), mechanical anastomosis (1.11%) and experience of the surgeon (11.1%). Five studies (55.6%) reported the area under the curve (AUC) of the scores, and four (44.4%) included a validation set.

CONCLUSION

Existing scores are heterogeneous in the identification of pre-operative variables allowing predicting AL. A majority of scores was established from small cohorts of patients which, considering the low incidence of AL, might lead to miss potential predictors of AL. AUC is seldom reported. We recommend that new scores to predict the risk of AL in colorectal surgery to be based on large cohorts of patients, to include a validation set and to report the AUC.

Systematic review of preoperative and intraoperative colorectal Anastomotic Leak Prediction Scores (ALPS)

OBJECTIVE

To systematically review preoperative and intraoperative Anastomotic Leak Prediction Scores (ALPS) and validation studies to evaluate performance and utility in surgical decision-making. Anastomotic leak (AL) is the most feared complication of colorectal surgery. Individualised leak risk could guide anastomosis and/or diverting stoma.

METHODS

Systematic search of Ovid MEDLINE and Embase databases, 30 October 2020, identified existing ALPS and validation studies. All records including >1 risk factor, used to develop new, or to validate existing models for preoperative or intraoperative use to predict colorectal AL, were selected. Data extraction followed CHecklist for critical Appraisal and data extraction for systematic Reviews of prediction Modelling Studies guidelines. Models were assessed for applicability for surgical decision-making and risk of bias using Prediction model Risk Of Bias ASsessment Tool.

RESULTS

34 studies were identified containing 31 individual ALPS (12 colonic/colorectal, 19 rectal) and 6 papers with validation studies only. Development dataset patient populations were heterogeneous in terms of numbers, indication for surgery, urgency and stoma inclusion. Heterogeneity precluded meta-analysis. Definitions and timeframe for AL were available in only 22 and 11 ALPS, respectively. 26/31 studies used some form of multivariable logistic regression in their modelling. Models included 3-33 individual predictors. 27/31 studies reported model discrimination performance but just 18/31 reported calibration. 15/31 ALPS were reported with external validation, 9/31 with internal validation alone and 4 published without any validation. 27/31 ALPS and every validation study were scored high risk of bias in model analysis.

CONCLUSIONS

Poor reporting practices and methodological shortcomings limit wider adoption of published ALPS. Several models appear to perform well in discriminating patients at highest AL risk but all raise concerns over risk of bias, and nearly all over wider applicability. Large-scale, precisely reported external validation studies are required.

PROSPERO REGISTRATION NUMBER

CRD42020164804.

Short-Term Outcomes in Patients Undergoing Virtual/Ghost Ileostomy or Defunctioning Ileostomy after Anterior Resection of the Rectum: A Meta-Analysis

BACKGROUND AND OBJECTIVES

Anterior rectal resection (ARR) represents one of the most frequently performed methods in colorectal surgery, mainly carried out for rectal cancer (RC) treatment. Defunctioning ileostomy (DI) has long been chosen as a method to "protect" colorectal or coloanal anastomosis after ARR. However, DI does not rule out risks of more or less serious complications. A proximal intra-abdominal closed-loop ileostomy, the so-called virtual/ghost ileostomy (VI/GI), could limit the number of DIs and the associated morbidity.

MATERIALS AND METHODS

We performed a systematic review following the Preferred Reporting Items for Systematic Reviews and Meta-Analyzes (PRISMA) guidelines. Meta-analysis was performed by use of RevMan [Computer program] Version 5.4.

RESULTS

The five included comparative studies (VI/GI or DI) covering an approximately 20-year study period (2008-2021). All included studies were observational ones and originated from European countries. Meta-analysis indicated VI/GI as significantly associated with lower short-term morbidity rates related to VI/GI or DI after primary surgery (RR: 0.21, 95% CI: 0.07-0.64, p = 0.006), fewer dehydration (RR: 0.17, 95% CI: 0.04-0.75, p = 0.02) and ileus episodes after primary surgery (RR: 0.20, 95% CI: 0.05-0.77, p = 0.02), fewer readmissions after primary surgery (RR: 0.17, 95% CI: 0.07-0.43, p = 0.0002) and readmissions after primary surgery plus stoma closure surgery (RR: 0.14, 95% CI: 0.06-0.30, p < 0.00001) than the DI group. On the contrary, no differences were identified in terms of AL after primary surgery, short-term morbidity after primary surgery, major complications (CD ≥ III) after primary surgery and length of hospital stay after primary surgery. Conclusions: Given the significant biases among meta-analyzed studies (small overall sample size and the small number of events analyzed, in particular), our results require careful interpretation. Further randomized, possibly multi-center trials may be of paramount importance in confirming our results.

Prediction model of anastomotic leakage after anterior resection for rectal cancer-based on nomogram and multivariate analysis with 1995 patients

BACKGROUND

Postoperative anastomotic leakage for rectal cancer shows higher morbidity with grievous concomitant symptoms. Accurate assessment of the incidence of anastomotic leakage, multivariate analysis, and establishment of a scientific prediction model can be useful to dispose of its possible severe clinical consequences.

METHODS

This retrospective study collected 1995 consecutive patients who underwent anterior resection of rectal cancer with primary anastomosis at Northern Jiangsu People's Hospital between January 2016 and June 2022. Independent risk factors associated with anastomotic leakage were analyzed by univariate and multivariate logistic regression. The chosen independent risk factors were used to construct a nomogram risk prediction model whose availability was evaluated by using a bootstrapped-concordance index and calibration plots with R software.

RESULTS

A total of 1995 patients who underwent anterior resection for rectal cancer were included while 120 patients were diagnosed with anastomotic leakage, an incidence of 6.0%. Univariate analysis and its concomitant multivariate cox regression analysis indicated that independent risk factors associated with anastomotic leakage included male gender (odds ratio (OR) = 2.873), diabetes (OR = 2.480), neoadjuvant therapy (OR = 5.283), tumor's distance from the anus verge < 5 cm (OR = 5.824), tumor size ≥ 5 cm (OR = 4.888), and the blood lose > 50 mL (OR = 9.606).We established a nomogram prediction model with proper applicability (concordance index, 0.83) and the calibration curve to justify its predictive ability that the predicted occurrence probability keeps a high degree of consistency with the actual occurrence probability. Meanwhile, the area under the receiver operating characteristic (ROC) curve was 0.83.

CONCLUSIONS

The characteristics of patients and tumor surgery-related conditions can affect the incidence of anastomotic leakage. However, whether the surgical method will affect morbidity is still controversial. Our nomogram can be seen as an effective instrument to predict anastomotic leakage after anterior resection for rectal cancer precisely.

Risk Factors for Predicting Lymph Node Metastasis in Submucosal Colorectal Cancer

Objectives:

The cornerstone of treating colorectal cancer (CRC) is generally a surgical resection with lymph node (LN) dissection. The tools for predicting lymph node metastasis (LNM) in submucosal (SM) CRC are useful to avoid unnecessary surgical resection.

Methods:

Retrospectively, we analyzed 526 consecutive patients with SM CRC who underwent surgical resection at the Osaka International Cancer Institute, Osaka University Hospital, and Minoh City Hospital, Japan, between 1984 and 2012. The Osaka International Cancer Institute group and the Osaka University Hospital group were randomly divided into a training set and a test set of 2:1. The prediction model was validated in Minoh City Hospital.

Results:

We partitioned patients using three risk factors involved in the presence or absence of LNM in SM CRC: lymphatic invasion (Ly), budding grade (BD) and the depth of submucosal invasion (DSI) (cut-off value 2789 μm) that were significantly different in the multivariate analysis. As a result, a predictive model of “LNM <5%” when “Ly negative and DSI <2789 μm” was evaluated. We similarly partitioned by DSI 3000 μm as easy-to-evaluate values in clinical use. We developed the additional model for predicting LNM is 1.05%, that is, LNM <5%, when there are “Ly negative and DSI <3000 μm.”

Conclusions:

As a limitation, only patients who underwent surgical resection were included in this study. This predictive model could help clinicians and CRC patients decide on the additional surgery required after endoscopic resection.

Updates of Risk Factors for Anastomotic Leakage after Colorectal Surgery

Anastomotic leakage is a potentially severe complication occurring after colorectal surgery and can lead to increased morbidity and mortality, permanent stoma formation, and cancer recurrence. Multiple risk factors for anastomotic leak have been identified, and these can allow for better prevention and an earlier diagnosis of this significant complication. There are nonmodifiable factors such as male gender, comorbidities and distance of tumor from anal verge, and modifiable risk factors, including smoking and alcohol consumption, obesity, preoperative radiotherapy and preoperative use of steroids or non-steroidal anti-inflammatory drugs. Perioperative blood transfusion was shown to be an important risk factor for anastomotic failure. Recent studies on the laparoscopic approach in colorectal surgery found no statistical difference in anastomotic leakage rate compared with open surgery. A diverting stoma at the time of primary surgery does not appear to reduce the leak rate but may reduce its clinical consequences and the need for additional surgery if anastomotic leakage does occur. It is still debatable if preoperative bowel preparation should be used, especially for left colon and rectal resections, but studies have shown similar incidence of postoperative leak rate.

Defining Anastomotic Leaks After Colorectal Surgery: Results of a National Survey

BACKGROUND

Anastomotic leaks are a dreaded complication after colorectal surgery. Although anastomotic leak is often used as a metric to compare patient outcomes, a standard definition does not exist.

MATERIALS AND METHODS

A web-based survey was developed and distributed to US surgeons. Respondents were queried on the definition of anastomotic leaks using a 5-point Likert scale to rate different scenarios related to colorectal surgery.

RESULTS

Of potential 2209 respondents, 649 (29%) responded to the survey. The majority of respondents was men (76%) and practiced colon and rectal surgery as their primary specialty (89%). Contrast extravasation at the anastomosis, regardless of timing related to the surgery, is the clinical scenario with greatest consensus (>85%). 50% of surgeons do not believe that an abscess near the anastomosis in an asymptomatic patient defines a leak.

CONCLUSIONS

These results highlight the pressing need for standardization of the anastomotic leak definition given the implications on outcomes measurement, research trials, and health care reimbursement.

Risk prediction models for postoperative outcomes of colorectal cancer surgery in the older population - a systematic review

BACKGROUND

An increasing number of patients with Colorectal Cancer (CRC) is 65 years or older. We aimed to systematically review existing clinical prediction models for postoperative outcomes of CRC surgery, study their performance in older patients and assess their potential for preoperative decision making.

METHODS

A systematic search in Pubmed and Embase for original studies of clinical prediction models for outcomes of CRC surgery. Bias and relevance for preoperative decision making with older patients were assessed using the CHARMS guidelines.

RESULTS

26 prediction models from 25 publications were included. The average age of included patients ranged from 61 to 76. Two models were exclusively developed for 65 and older. Common outcomes were mortality (n = 10), anastomotic leakage (n = 7) and surgical site infections (n = 3). No prediction models for quality of life or physical functioning were identified. Age, gender and ASA score were common predictors; 12 studies included intraoperative predictors. For the majority of the models, bias for model development and performance was considered moderate to high.

CONCLUSIONS

Prediction models are available that address mortality and surgical complications after CRC surgery. Most models suffer from methodological limitations, and their performance for older patients is uncertain. Models that contain intraoperative predictors are of limited use for preoperative decision making. Future research should address the predictive value of geriatric characteristics to improve the performance of prediction models for older patients.

Development of a Risk Score to Predict Anastomotic Leak After Left-Sided Colectomy: Which Patients Warrant Diversion?

BACKGROUND

Anastomotic leak is a feared complication after left-sided colectomy, but its risk can potentially be reduced with the use of a diverting ostomy. However, an ostomy has its own associated negative sequelae; therefore, it is critical to appropriately identify patients to divert. This is difficult in practice since many risk factors for anastomotic leak exist and outside factors bias this decision. We aimed to develop and validate a risk score to predict an individual's risk of anastomotic leak and aid in the decision.

METHODS

The American College of Surgeons National Surgical Quality Improvement Program Colectomy Targeted PUF was queried from 2012 to 2016 for patients undergoing elective left-sided resection for malignancy, benign neoplasm, or diverticular disease. Multivariable logistic regression identified predictors of anastomotic leak in non-diverted patients, and a risk score was developed and validated.

RESULTS

38,475 patients underwent resection with an overall anastomotic leak rate of 3%. Independent risk factors for anastomotic leak included younger age, male sex, tobacco use, and omission of combined bowel preparation. A risk score incorporating independent predictors demonstrated excellent calibration. There was strong visual correspondence between predicted and observed anastomotic leak rates. 3960 patients underwent resection with diversion, yet over half of these patients had a predicted leak rate of less than 4%.

CONCLUSION

A novel risk score can be used to stratify patients according to anastomotic leak risk after elective left-sided resection. Intraoperative calculation of scores for patients can help guide surgical decision-making in both diverting the highest risk patients and avoiding diversion in low-risk patients.

Preventive strategies for anastomotic leakage after colorectal resections: A review

Anastomosis is a crucial step in radical cancer surgery. Despite being a daily practice in gastrointestinal surgery, anastomotic leakage (AL) stands as a frequent postoperative complication. Because of increased morbidity, mortality, combined with longer hospital stay, the rate of re-intervention, and poor oncological outcomes, AL is considered the most feared and life-threatening complication after colorectal resections. Furthermore, poor functional outcomes with a higher rate of a permeant stoma in 56% of patients this could negatively affect the patient’s quality of life. This a narrative review which will cover intraoperative anastomotic integrity assessment and preventive measures in order to reduce AL. Although the most important prerequisites for the creation of anastomosis is well-perfused and tension-free anastomosis, surgeons have proposed several preventive measures, which were assumed to reduce the incidence of AL, including antibiotic prophylaxis, intraoperative air leak test, omental pedicle flap, defunctioning stoma, pelvic drain insertion, stapled anastomosis, and general surgical technique. However, lack of clear evidence of which preventive measures is superior over the other combined with the fact that the decision remains based on the surgeon’s choice. Despite the advances in surgical techniques, AL remains a serious health problem associated with increased morbidity, mortality with additional cost. Many preventative measures were employed with no clear evidence supporting the superiority of stapled anastomosis over hand-Sewn anastomosis, coating of the anastomosis, or pelvic drain. Defunctioning stoma, when justified it could decrease the leakage-related complications and the incidence of reoperation. MBP combined with oral antibiotics still recommended.

A Nomogram for Predicting Lymph Node Metastasis in Submucosal Colorectal Cancer

In colorectal cancer (CRC), the possibility of lymph node (LN) metastasis is an important consideration when deciding on treatment. We developed a nomogram for predicting lymph node metastasis of submucosal (SM) CRC. The medical records of 509 patients with SM CRC from 1984 to 2012 were retrospectively investigated. All the patients underwent curative surgical resection at the Osaka Medical Center for Cancer and Cardiovascular Diseases. A total 113 patients with inadequate data were excluded. Using a group of 293 patients who underwent surgery from 1984 to 2008, a logistic regression model was used to develop a prediction model for LN metastasis. The prediction model was validated in an additional group of 103 patients who underwent surgery from 2009 to 2012. Univariate analysis of pathologic factors showed the influence of low histologic grade (muc, por, sig; P &lt; 0.001), positive lymphatic invasion (P &lt; 0.001), positive vascular invasion (P = 0.036), and tumor SM invasion depth (P = 0.098) in LN metastasis. Using these variables, a nomogram predicting LN metastasis was constructed using a logistic regression model with an area under the curve (AUC) of 0.717. The prediction model was validated by an external dataset in an independent patient group with an AUC of 0.920. We developed a novel and reliable nomogram predicting LN metastasis through the integration of 4 pathologic factors. This prediction model may help clinicians to decide on personalized treatment following endoscopic resection.

Reviewing the Management of Obstructive Left Colon Cancer: Assessing the Feasibility of the One-stage Resection and Anastomosis After Intraoperative Colonic Irrigation

BACKGROUND

The management of obstructive left colon cancer (OLCC) remains debatable with the single-stage procedure of primary colonic anastomosis after cancer resection and on-table intracolonic lavage now being supported.

PATIENTS AND METHODS

Patients with acute OLCC who were admitted between January 2008 and January 2015 were distributed into 5 different groups. Group ICI underwent emergency laparotomy for primary anastomosis following colonic resection and intraoperative colonic lavage; Group HP underwent emergency Hartmann's Procedure; Group CON consisted of patients treated by conservative management with subsequent elective open cancer resection; Group COL were colostomy patients; and Group INT consisted of patients who had interventional radiology followed by open elective colon cancer resection. The demographics of the patients and comorbidity, intraoperative data, and postoperative data were collected, with P < .05 as significant.

RESULTS

There were 4 deaths in 138 cases (2.90%). There was only 1 patient who had anastomotic leakage (5.56%) in Group ICI, compared with none in Group HP and Group COL, 1 case in Group INT (7.69%), and 2 cases in Group CON (6.06%) (P > .05). Group INT and Group CON, when compared to the three surgical groups, Groups ICI, Group COL, and Group HP, individually, were statistically significant for the duration of surgery (P < .05).

CONCLUSIONS

Primary anastomosis following colonic resection after irrigation can be safely performed in selected patients, with the necessary surgical expertise, with no increased risk in mortality, anastomotic leakage, and other postoperative complications.

Monitoring perioperative serum albumin can identify anastomotic leakage in colorectal cancer patients with curative intent

BACKGROUND

Preoperative hypoalbuminemia is a well-known risk factor for anastomotic leakage after colorectal surgery, but the association between perioperative albumin level and anastomotic leakage has not been fully investigated in curative colorectal cancer (CRC) patients.

METHODS

In total, 200 CRC patients (Stage I-III) undergoing curative laparoscopic surgery between January 2004 and December 2013 were enrolled in this study. We collected data on surgical factors, perioperative levels of serum albumin and inflammatory markers, and perioperative factors affecting hypoalbuminemia from 196 CRC patients to assess the relation to anastomotic leakage.

RESULTS

Anastomotic leakage occurred in 11 cases (5.6%) and the frequency was higher in rectal cancer patients (p = 0.0044). There was no significant difference of preoperative serum albumin level between the anastomotic leakage group (AL) and the nonanastomotic leakage group (NAL). Postoperative serum albumin levels in AL were significantly lower than in NAL [postoperative day (POD) 0, p = 0.0004; POD1, p = 0.0001; POD3, p = 0.0004; and POD7, p = 0.0021]. On multivariate analysis, lower average level of serum albumin on POD1 and POD3 {odds ratio (OR) [95% confidence interval (CI)] = 7.53 (1.60-55.80), p = 0.0095}, higher average level of serum white blood cells on POD1 and POD3 [OR (95% CI) = 7.24 (1.40-59.25), p = 0.0165], and surgery for rectal cancer [OR (95% CI) = 15.18 (3.26-93.99), p = 0.0004] were independent risk factors for anastomotic leakage.

CONCLUSION

Lower early postoperative serum albumin levels are a potentially valuable indicator of anastomotic leakage in CRC patients undergoing curative surgery.

A Multicentre Evaluation of Risk Factors for Anastomotic Leakage After Restorative Proctocolectomy with Ileal Pouch-Anal Anastomosis for Inflammatory Bowel Disease

BACKGROUND

Anastomotic leakage is a major complication after restorative proctocolectomy with ileal pouch-anal anastomosis [IPAA]. Identification of patients at high risk of leakage may influence surgical decision making. The aim of this study was to identify risk factors associated with anastomotic leakage after restorative proctocolectomy with IPAA.

METHODS

Between September 1990 and January 2015, patients who underwent IPAA for inflammatory bowel disease [IBD] were identified from prospectively maintained databases of three tertiary referral centres. Retrospective chart review identified additional data on demographic and surgical variables. Multivariable regression models were developed to identify risk factors for anastomotic leakage. Separate analyses were performed for type of procedure.

RESULTS

A total of 640 patients [56.9% male] were included, with a median age of 38 years [interquartile range 29-48]; 96 [15.0%] patients developed anastomotic leakage. Multivariable regression analysis demonstrated that being overweight (body mass index [BMI] > 25], (odds ratio [OR] 1.92; 95% confidence interval [CI] 1.15 - 3.18), and American Society of Anesthesiologists classification [ASA score > 2] [OR 1.91; 95% CI 1.03 - 3.54] were independent risk factors for anastomotic leakage in patients who underwent a completion proctectomy. A disease course of > 5 years [OR 2.34; 95% CI 1.42 - 3.87] and concurrent combination of anti-tumour necrosis factor [TNF] and steroids [OR 6.40; 95% CI 1.76 - 23.20] were independent risk factors for anastomotic leakage in patients who underwent a proctocolectomy and IPAA.

CONCLUSIONS

Independent risk factors for anastomotic leakage in IBD patients undergoing IPAA are BMI >25, ASA score >2, disease course > 5 years, and concurrent steroid and anti-TNF treatment, with a different risk profile for one-stage proctocolectomy and completion proctectomy procedures.

Colorectal anastomotic healing: why the biological processes that lead to anastomotic leakage should be revealed prior to conducting intervention studies

BACKGROUND

Anastomotic leakage (AL) remains the most dreaded complication after colorectal surgery and causes high morbidity and mortality. The pathophysiology of AL remains unclear, despite numerous studies that have been conducted on animals and humans, probably due to the undetermined healing process of colorectal anastomoses. Increasing basic knowledge on this healing process may shed more light on causal factors of AL, and additionally reduce the quantity and accelerate the quality of experimental studies. In this debate article, our aim was to provide different perspectives on what is known about the colorectal healing process in relation to wound healing and AL.

DISCUSSION

Since knowledge on anastomotic healing is lacking, it remains difficult to conclude which factors are essential in preventing AL. This is essential information in the framework of humane animal research, where the focus should lie on Replacement, Reduction and Refinement (3Rs). While many researchers compare anastomotic healing with wound healing in the skin, there are substantial recognized differences, e.g. other collagen subtypes and different components involved. Based on our findings in literature as well as discussions with experts, we advocate stop considering anastomotic healing in the gastrointestinal tract and cutaneous healing as a similar process. Furthermore, intervention studies should at least address the anastomotic healing process in terms of histology and certain surrogate markers. Finally, the anastomotic healing process ought to be further elucidated - with modern techniques to achieve 3Rs in animal research--to provide starting points for potential interventions that can prevent AL.

A Four-Probiotics Regimen Reduces Postoperative Complications After Colorectal Surgery: A Randomized, Double-Blind, Placebo-Controlled Study

BACKGROUND

Heterogeneous results of published studies led to conduct a randomized clinical trial to assess the efficacy of a new formulation of four probiotics as prophylaxis for complications after colorectal surgery.

METHODS

A double-blind, placebo-controlled randomized study was conducted enrolling patients undergoing colorectal surgery for cancer. Capsules of placebo or of a formulation containing Lactobacillus acidophilus, L. p lantarum, Bifidobacterium lactis and Saccharomyces boulardii were administered starting one day before operation and continuing for another 15 days postoperatively. Patients were followed up for 30 days with the development of postoperative complications as the primary outcome. Gene expression and serum levels of cytokines were measured on postoperative day 4 ( www.clinicaltrials.gov NCT02313519).

RESULTS

The study was prematurely stopped after enrolment due to efficacy in the primary outcome. Administration of probiotics significantly decreased the rate of all postoperative major complication (28.6 vs. 48.8 % of the placebo arm, p 0.010, odds ratio 0.42). Major benefit was found in the reduction of the rate of postoperative pneumonia (2.4 vs. 11.3 %, p 0.029), of surgical site infections (7.1 vs. 20.0 %, p 0.020) and of anastomotic leakage (1.2 vs. 8.8 %, p 0.031). The time until hospital discharge was shortened as well. Gene expression of SOCS3 was positively related with gene expression of TNF and of circulating IL-6 in the probiotic group but not in the placebo group.

CONCLUSIONS

The studied probiotic formulation significantly decreased the risk of postoperative complications, namely mechanical ventilation, infections and anastomotic leakage. Modulation of the gene expression of SOCS3 is one suggested mechanism ( www.clinicaltrials.gov NCT02313519).

Endo-sponge therapy for management of anastomotic leakages after colorectal surgery: A case series and review of literature

BACKGROUND

Endo-sponge treatment is a novel approach to manage selected patients with anastomotic leakage following colorectal surgery. However, the available data are still scanty.

AIMS

To evaluate the efficacy and safety of the endo-sponge therapy in a large series, and to perform a review of the current evidence concerning such a treatment.

METHODS

Consecutive patients diagnosed with partial colonic anastomotic leakage managed with endo-sponge placement were enrolled. The endo-sponge system was changed every 48-72 h as outpatient, until to cavity closure. Literature review was performed for pooled-data analysis.

RESULTS

Twenty-five patients were enrolled, including 13 (52%) with diverting ileostomy. Following endo-sponge applications (median sessions: 9, range: 1-39; median treatment duration: 4 weeks, range: 1-32), a complete healing was achieved in 22 (88%) patients. Three (12%) patients developed a major complication (1 uretheric fistula, 1 ileal fistula, and 1 pararectal abscess), all successfully treated by surgery. Ileostomy closure was achieved in 11 (84.6%) patients. No mortality related to the procedure was observed. Overall, 174 patients treated with endo-sponge were reported in literature. By considering data of the larger 7 studies, a complete healing of presacral cavity was achieved in 131 (94.3%) out of 149 patients.

CONCLUSIONS

Our relatively large series of patients confirmed the efficacy, tolerability, and an acceptably low complication rate of endo-sponge therapy for colorectal anastomosis leakage treatment.

Influence of CD68+ macrophages and neutrophils on anastomotic healing following laparoscopic sigmoid resection due to diverticulitis

BACKGROUND

The aim of this prospective study was to evaluate the predictive value of a potential preexisting low-grade inflammation regarding the incidence of anastomotic leakage in elective laparoscopic sigmoid resection due to diverticulitis.

METHODS

Patients with either chronically recurrent diverticulitis or sigmoid stenosis caused by chronic diverticulitis were included in this study. All patients with acute local or systemic inflammation were excluded. Detailed patient information (e.g. American Society of Anesthesiologists (ASA) grade, comorbidities, duration of hospital stay, and anastomotic leakage) was prospectively recorded. CD68(+) macrophages, neutrophils, CD3(+) T-lymphocytes, CD11c(+) dendritic cells, MHCII, TNFR1, and NF-κB were evaluated by immunohistochemistry within the acquired sample of colonic bowel wall tissue. Clinical and immunohistochemical data was compared between groups (leakage vs. no leakage). Additionally, a matched-pair analysis was performed due to the widely heterogeneous groups concerning the number of patients and to minimize the effect of extraneous variables.

RESULTS

A total of 83 patients were included in the study, of which 7 patients suffered an anastomotic leakage. Neither the clinical nor the immunohistochemical parameters were significantly different between the groups. The matched-pair analysis revealed a nonsignificant increase in mean duration of hospital stay for the group with anastomotic leakage and a significantly higher percentage of CD68(+) macrophages and neutrophils in the colonic wall obtained at the index operation in both the mucosal and submucosal layers for the leakage group.

CONCLUSIONS

A preexisting low-grade inflammation represented by infiltrates of macrophages and neutrophils is a predictor for increased risk of developing colon anastomotic leakage.