Anastomotic leak in colorectal cancer patients: New insights and perspectives

Procalcitonin and C-reactive protein as early predictors in patients at high risk of colorectal anastomotic leakage

OBJECTIVE

To assess the diagnostic value of C-reactive protein (CRP) and procalcitonin (PCT) for anastomotic leakage (AL) following colorectal surgery.

METHODS

We retrospectively analyzed data for patients who underwent colorectal surgery at our hospital between November 2019 and December 2023. CRP and PCT were measured postoperatively to compare patients with/without AL, and changes were compared between low- and high-risk groups. Receiver operating characteristic (ROC) curve analysis was used to assess the diagnostic accuracy of CRP and PCT to identify AL in high-risk patients.

RESULTS

Mean CRP was 142.53 mg/L and 189.57 mg/L in the low- and high-risk groups, respectively, on postoperative day (POD)3. On POD2, mean PCT was 2.75 ng/mL and 8.16 ng/mL in low- and high-risk patients, respectively; values on POD3 were 3.53 ng/mL and 14.86 ng/mL, respectively. The areas under the curve (AUC) for CRP and PCT on POD3 were 0.71 and 0.78, respectively (CRP cut-off: 235.64 mg/L; sensitivity: 96%; specificity: 89.42% vs PCT cut-off: 3.94 ng/mL; sensitivity: 86%; specificity: 93.56%; AUC: 0.78). The AUC, sensitivity, and specificity for the combined diagnostic ability of CRP and PCT on POD3 were 0.92, 90%, and 100%, respectively (cut-off: 0.44).

CONCLUSIONS

Combining PCT and CRP on POD3 enhances the diagnostic accuracy for AL.

Perioperative Blood Transfusions and Anastomotic Leak After Colorectal Surgery for Cancer in an Australian Hospital

PURPOSE

Peri-operative blood transfusion has been identified as a risk factor for anastomotic leak in recent studies, but little is known about which patients are at risk for blood transfusion. This study aims to assess the relationship between blood transfusion and anastomotic leak and factors predisposing to leak in patients undergoing colorectal cancer surgery.

METHODS

This retrospective cohort study was conducted in a tertiary hospital in Brisbane, Australia, between 2010 and 2019. A total of 522 patients underwent resection of colorectal cancer with primary anastomosis with no covering stoma and the prevalence of anastomotic leak was compared between those who had had perioperative blood transfusion(s) and those who had not.

RESULTS

A total of 19 of 522 patients undergoing surgery for colorectal cancer had developed an anastomotic leak (3.64%). 11.3% of patients who had had a perioperative blood transfusion developed an anastomotic leak whereas 2.2% of patients who had not had a blood transfusion developed an anastomotic leak (p = 0.0002). Patients undergoing procedure on their right colon had proportionally more blood transfusions and this approached statistical significance (p = 0.06). Patients who received a greater quantity of units of blood transfusion prior to their diagnosis of anastomotic leak were more likely to develop an anastomotic leak (p = 0.001).

CONCLUSION

Perioperative blood transfusions are associated with a significantly increased risk of an anastomotic leak following bowel resection with primary anastomosis for colorectal cancer.

Preoperative neutrophil-to-lymphocyte ratio predicts symptomatic anastomotic leakage in elderly colon cancer patients: Multicenter propensity score-matched analysis

BACKGROUND

The neutrophil-to-lymphocyte ratio (NLR), a composite inflammatory biomarker, is associated with the prognosis in patients with colorectal tumors. However, whether the NLR can be used as a predictor of symptomatic postoperative anastomotic leakage (AL) in elderly patients with colon cancer is unclear.

AIM

To assess the role of the NLR in predicting the occurrence of symptomatic AL after surgery in elderly patients with colon cancer.

METHODS

Data from elderly colon cancer patients who underwent elective radical colectomy with anastomosis at three centers between 2018 and 2022 were retrospectively analyzed. Receiver operating characteristic curve analysis was performed to determine the best predictive cutoff value for the NLR. Twenty-two covariates were matched using a 1:1 propensity score matching method, and univariate and multivariate logistic regression analyses were used to determine risk factors for the development of postoperative AL.

RESULTS

Of the 577 patients included, 36 (6.2%) had symptomatic AL. The optimal cutoff value of the NLR for predicting AL was 2.66. After propensity score matching, the incidence of AL was significantly greater in the ≥ 2.66 NLR subgroup than in the < 2.66 NLR subgroup (11.5% vs 2.5%; P = 0.012). Univariate logistic regression analysis revealed statistically significant correlations between blood transfusion intraoperatively and within 2 d postoperatively, preoperative albumin concentration, preoperative prognostic nutritional index, and preoperative NLR and AL occurrence (P < 0.05); multivariate logistic regression analysis revealed that an NLR ≥ 2.66 [odds ratio (OR) = 5.51; 95% confidence interval (CI): 1.50-20.26; P = 0.010] and blood transfusion intraoperatively and within 2 d postoperatively (OR = 2.52; 95%CI: 0.88-7.25; P = 0.049) were risk factors for the occurrence of symptomatic AL.

CONCLUSION

A preoperative NLR ≥ 2.66 and blood transfusion intraoperatively and within 2 d postoperatively are associated with a higher incidence of postoperative symptomatic AL in elderly patients with colon cancer. The preoperative NLR has predictive value for postoperative symptomatic AL after elective surgery in elderly patients with colon cancer.

The value of C-reactive protein, leucocytes and vital signs in detecting major complications after oncological colorectal surgery

PURPOSE

To assess the association of postoperative C-reactive protein (CRP), leucocytes and vital signs in the first three postoperative days (PODs) with major complications after oncological colorectal resections in a tertiary referral centre for colorectal cancer in The Netherlands.

METHODS

A retrospective cohort study, including 594 consecutive patients who underwent an oncological colorectal resection at Maastricht University Medical Centre between January 2016 and December 2020. Descriptive analyses of patient characteristics were performed. Logistic regression models were used to assess associations of leucocytes, CRP and Modified Early Warning Score (MEWS) at PODs 1-3 with major complications. Receiver operating characteristic curve analyses were used to establish cut-off values for CRP.

RESULTS

A total of 364 (61.3%) patients have recovered without any postoperative complications, 134 (22.6%) patients have encountered minor complications and 96 (16.2%) developed major complications. CRP levels reached their peak on POD 2, with a mean value of 155 mg/L. This peak was significantly higher in patients with more advanced stages of disease and patients undergoing open procedures, regardless of complications. A cut-off value of 170 mg/L was established for CRP on POD 2 and 152 mg/L on POD 3. Leucocytes and MEWS also demonstrated a peak on POD 2 for patients with major complications.

CONCLUSIONS

Statistically significant associations were found for CRP, Δ CRP, Δ leucocytes and MEWS with major complications on POD 2. Patients with CRP levels ≥ 170 mg/L on POD 2 should be carefully evaluated, as this may indicate an increased risk of developing major complications.

Development and Validation of a Novel Nomogram Model for Early Diagnosis of Anastomotic Leakage After Laparoscopic Colorectal Cancer Surgery

Background: This study aimed to investigate the clinical value of inflammatory factors for predicting anastomotic leakage (AL) after laparoscopic colorectal cancer surgery and establish a nomogram model to assess the probability of its occurrence. Patients and Methods: Data of 637 patients who underwent laparoscopic colorectal cancer surgery between June 2019 and June 2022 were collected. Differences in procalcitonin (PCT), C-reactive protein (CRP), and white blood cell (WBC) levels before surgery and on postoperative day (POD) 3 and 5 were compared between patients with and without AL (AL and non-AL groups, respectively). The diagnostic accuracy was determined using the area under the receiver operating characteristic curve (AUC), and a nomogram model was developed. Results: Post-operative AL occurred in 46 (7.2%) patients. Procalcitonin, CRP, and WBC levels on POD 3 and 5 were higher in the AL group than in the non-AL group. The AUCs of PCT, CRP, and WBC levels for predicting AL on POD 3 were 0.833, 0.757, and 0.756, respectively, which were better than those on POD 5 (AUC = 0.669, 0.581, and 0.588, respectively). The nomogram model for AL was developed based on five variables (PCT, CRP, WBC, American Society of Anesthesiologists [ASA] grade and comorbidities), and it had an AUC of 0.922. Calibration curves demonstrated that the nomogram had good fit. The Delong test showed that the AUC of the nomogram for predicting the probability of AL was higher than that of PCT alone (z = 2.311, p = 0.02). Conclusions: Procalcitonin measured on POD 3 seems to be a promising negative predictor of AL after laparoscopic colorectal cancer surgery. Furthermore, the nomogram model developed in our study, which utilizes a series of predictors that can be easily accessed, has demonstrated potential to further improve the prediction accuracy.

Diet-induced shifts in the gut microbiota influence anastomotic healing in a murine model of colonic surgery

Host diet and gut microbiota interact to contribute to perioperative complications, including anastomotic leak (AL). Using a murine surgical model of colonic anastomosis, we investigated how diet and fecal microbial transplantation (FMT) impacted the intestinal microbiota and if a predictive signature for AL could be determined. We hypothesized that a Western diet (WD) would impact gut microbial composition and that the resulting dysbiosis would correlate with increased rates of AL, while FMT from healthy, lean diet (LD) donors would reduce the risk of AL. Furthermore, we predicted that surgical outcomes would allow for the development of a microbial preclinical translational tool to identify AL. Here, we show that AL is associated with a dysbiotic microbial community characterized by increased levels of Bacteroides and Akkermansia. We identified several key taxa that were associated with leak formation, and developed an index based on the ratio of bacteria associated with the absence and presence of leak. We also highlight a modifiable connection between diet, microbiota, and anastomotic healing, potentially paving the way for perioperative modulation by microbiota-targeted therapeutics to reduce AL.

Patient Factors Affecting Inpatient Mortality Following Colorectal Cancer Resection

BACKGROUND

Our objective is to identify factors for inpatient death in patients undergoing resection for colorectal cancer (CRC).

STUDY DESIGN

Unmatched 1:3 case-control study of surgically resected CRC at a tertiary care institution between 2004 and 2018. Variables for multivariate analysis were selected using tetrachoric correlation followed by a least absolute shrinkage and selection operator (LASSO) penalized regression model.

RESULTS

A total of 140 patients were included (N = 35 patients who died inpatient, N = 105 patients who did not die). Patients who died were older, had higher Charlson Comorbidity Index (CCI), higher rates of preoperative anemia, hypoalbuminemia, emergency surgeries, blood transfusion, postoperative vasopressor requirement, anastomotic leak, and postoperative ICU admission than patients who underwent surgical resection without inpatient mortality. Anemia (aOR = 8.62, 1.44-91.58), emergency admission (aOR = 5.71, 1.46-24.36), and ICU admission (aOR 45.51, 8.31-448.4) significantly predicted inpatient mortality when controlled for CCI and hypoalbuminemia.

CONCLUSIONS

Surprisingly, it appears that pre-existing anemia and perioperative factors are more important in predicting inpatient mortality of patients undergoing CRC surgery than baseline comorbidity or nutritional status.

Rates and risk factors for anastomotic leak following blunt trauma-associated bucket handle intestinal injuries: a multicenter study

Objectives

The risk factors for anastomotic leak (AL) after resection and primary anastomosis for traumatic bucket handle injury (BHI) have not been previously defined. This multicenter study was conducted to address this knowledge gap.

Methods

This is a multicenter retrospective study on small intestine and colonic BHIs from blunt trauma between 2010 and 2021. Baseline patient characteristics, risk factors, presence of shock and transfusion, operative details, and clinical outcomes were compared using R.

Results

Data on 395 subjects were submitted by 12 trauma centers, of whom 33 (8.1%) patients developed AL. Baseline details were similar, except for a higher proportion of patients in the AL group who had medical comorbidities such as diabetes, hypertension, and obesity (60.6% vs. 37.3%, p=0.015). AL had higher rates of surgical site infections (13.4% vs. 5.3%, p=0.004) and organ space infections (65.2% vs. 11.7%, p<0.001), along with higher readmission and reoperation rates (48.4% vs. 9.1%, p<0.001, and 39.4% vs. 11.6%, p<0.001, respectively). There was no difference in intensive care unit length of stay or mortality (p>0.05). More patients with AL were discharged with an ostomy (69.7% vs. 7.3%, p<0.001), and the mean duration until ostomy reversal was 5.85±3 months (range 2-12.4 months). The risk of AL significantly increased when the initial operation was a damage control procedure, after adjusting for age, sex, injury severity, presence of one or more comorbidities, shock, transfusion of >6 units of packed red blood cells, and site of injury (adjusted RR=2.32 (1.13, 5.17)), none of which were independent risk factors in themselves.

Conclusion

Damage control surgery performed as the initial operation appears to double the risk of AL after intestinal BHI, even after controlling for other markers of injury severity.

Level of evidence

III.

Anastomotic leak in colorectal cancer surgery: Contribution of gut microbiota and prediction approaches

AIM

To monitor prospectively the occurrence of colorectal anastomotic leakage (CAL) in patients with colon cancer undergoing resectional surgery, characterizing the microbiota in both faeces and mucosal biopsies of anastomosis. In a second stage, we investigated the ability to predict CAL using machine learning models based on clinical data and microbiota composition.

METHOD

A total of 111 patients were included, from whom a faecal sample was obtained, as well as biopsy samples from proximal and distal sites in the healthy margins of the tumour piece. The microorganisms present in the samples were investigated using microbial culture and 16S rDNA massive sequencing. Collagenase and protease production was determined, as well as the presence of genes responsible for expressing enzymes with these activities. Machine learning analyses were developed using clinical and microbiological data.

RESULTS

The incidence of CAL was 9.0%, and CAL was associated with collagenase/protease-producing Enterococcus. Significant differences were found in the microbiota composition of proximal and distal biopsy samples, but not in faecal samples, among patients who developed CAL. Clinical predictors of CAL were 5-day C-reactive protein and heart disease, whereas 3-day C-reactive protein and diabetes were negative predictors.

CONCLUSION

Biopsy samples from surgical margins, rather than faecal samples, are the most appropriate samples for exploring the contribution of the intestinal microbiota to CAL. Enterococci are only enriched in the anastomosis after surgery, and their collagenases and proteases are involved in the degradation of the anastomotic scar.

Stoma-free Survival After Rectal Cancer Resection With Anastomotic Leakage: Development and Validation of a Prediction Model in a Large International Cohort

OBJECTIVE

To develop and validate a prediction model (STOMA score) for 1-year stoma-free survival in patients with rectal cancer (RC) with anastomotic leakage (AL).

BACKGROUND

AL after RC resection often results in a permanent stoma.

METHODS

This international retrospective cohort study (TENTACLE-Rectum) encompassed 216 participating centres and included patients who developed AL after RC surgery between 2014 and 2018. Clinically relevant predictors for 1-year stoma-free survival were included in uni and multivariable logistic regression models. The STOMA score was developed and internally validated in a cohort of patients operated between 2014 and 2017, with subsequent temporal validation in a 2018 cohort. The discriminative power and calibration of the models' performance were evaluated.

RESULTS

This study included 2499 patients with AL, 1954 in the development cohort and 545 in the validation cohort. Baseline characteristics were comparable. One-year stoma-free survival was 45.0% in the development cohort and 43.7% in the validation cohort. The following predictors were included in the STOMA score: sex, age, American Society of Anestesiologist classification, body mass index, clinical M-disease, neoadjuvant therapy, abdominal and transanal approach, primary defunctioning stoma, multivisceral resection, clinical setting in which AL was diagnosed, postoperative day of AL diagnosis, abdominal contamination, anastomotic defect circumference, bowel wall ischemia, anastomotic fistula, retraction, and reactivation leakage. The STOMA score showed good discrimination and calibration (c-index: 0.71, 95% CI: 0.66-0.76).

CONCLUSIONS

The STOMA score consists of 18 clinically relevant factors and estimates the individual risk for 1-year stoma-free survival in patients with AL after RC surgery, which may improve patient counseling and give guidance when analyzing the efficacy of different treatment strategies in future studies.

Metagenomics of microbiota following probiotic supplementation in rats subjected to intestinal anastomosis

Background

The use of probiotics positively modifies the composition and function of the intestinal flora, decreasing inflammation, and these changes improve the quality of intestinal anastomosis. Therefore, the objective of this study was to evaluate the metagenomics of the microbial community after probiotic supplementation in rats subjected to intestinal anastomosis.

Methods

The probiotic chosen for this study was composed of the strains Lactobacillus paracasei LPC37, Bifidobacterium lactis HN0019, Lactobacillus rhamnosus HN001 and Lactobacillus acidophilus NCFM. Both groups underwent two colostomies, one in the right colon and the second in the rectosigmoid colon, followed by anastomosis with eight interrupted stitches. The rats were killed on the fifth day of PO. Changes in the intestinal microbiota were evaluated by means of a metagenomic study that evaluated bacterial alpha and beta diversity indices.

Results

Although there were no significant differences for any alpha diversity index, changes were observed for beta diversity indexes in the microbiota of rats. The group that received the probiotic preserved and even increased the abundance of beneficial bacterial genera and, at the same time, decreased the abundance of potentially pathogenic bacteria, promoting a favorable environment for anastomoses' healing.

Conclusion

The use of probiotics had a positive impact on the quality of the intestinal microbiota.

Single-stapled anastomosis is associated with a lower anastomotic leak rate than double-stapled technique after minimally invasive total mesorectal excision for MRI-defined low rectal cancer

BACKGROUND

After total mesorectal excision, distal rectal transection and anastomosis are critical for short-term, oncological, and functional outcomes, including anastomotic leak. A double-pursestring, single-stapled anastomosis avoids cross-stapling, overcoming the potential drawbacks of transabdominal rectal transection and double-stapled anastomosis. This study aims to compare the anastomotic leak rate in double-stapled and single-stapled anastomoses after minimally invasive total mesorectal excision for magnetic resonance imaging-defined low rectal cancer.

METHODS

Adult patients (>18 years old) undergoing minimally invasive total mesorectal excision for magnetic resonance imaging-defined low rectal cancer with a stapled low anastomosis (below 5 centimeters from the anal verge) between January 2010 and January 2022 at a single institution were allocated to 2 groups according to the anastomosis: double-stapled (abdominal stapled transection and double-stapled anastomosis) or single-stapled (transanal rectal transection and double-pursestring single-stapled anastomosis). The exclusion criteria were nonrestorative procedures or any type of manual anastomosis. The primary endpoint was the rate of 90-day clinical and radiologic anastomotic leak.

RESULTS

In total, 185 single-stapled and 458 double-stapled were included. Clinical and tumor characteristics were comparable between the groups. The 90-day anastomotic leak rate was significantly lower in the single-stapled group (6.48% vs 15.28%; P = .002), with similar rates of grade and timing. Thirty- and 90-day complication rates were higher in the double-stapled group (P = .0001; P = .02), with comparable Clavien-Dindo grades. At multivariable analysis, double-stapled anastomosis (P = .01), active smoking (P = .03), and the presence of comorbidities (P = .01) resulted as independent risk factors for an anastomotic leak.

CONCLUSION

Transanal transection and double-pursestring, single-stapled anastomosis were associated with a lower anastomotic leak rate after minimally invasive total mesorectal excision for magnetic resonance imaging-defined low rectal cancer.

Safety and feasibility of robotic surgery for old rectal cancer patients

Robotic surgery is widely utilized for rectal cancer. Older patients are associated with comorbidity and diminished cardiopulmonary reserve, resulting in uncertainty and reluctance to perform robotic surgery in older patients. The aim of the study was to assess the safety and feasibility of robotic surgery in older rectal cancer patients. We collected the data of patients diagnosed with rectal cancer and operated at our hospital from May 2015 to January 2021. All patients undergoing robotic surgery were classified into two groups: the old group (≥ 70 years) and young group (< 70 years). Perioperative outcomes were analyzed and compared between the two groups. Risk factors related to postoperative complications were also explored. A total of old N = 114 and young N = 324 rectal patients were enrolled in our study. Older patients were prone to exhibit comorbidity than the young and had lower body mass index and higher scores of American Society of Anesthesiologists than the young. No statistical difference was found in operative time, estimated blood loss, lymph nodes retrieved, tumor size, pathological TNM stage, hospital stay after surgery and total hospital cost between the two groups. The incidence of postoperative complications did not show difference between the two groups. On multivariate analyses, male sex and longer operative time could predict postoperative complications, whereas old age was not an independent factor for postoperative complications. After careful preoperative evaluation, robotic surgery is a technically feasible and safe procedure for older rectal cancer patients.

Rationale for Colonic Pre-Habilitation Prior to Restoration of Gastrointestinal Continuity

The emergence of the gut microbiome as a complex ecosystem that plays a key role in human heath and disease has touched virtually every aspect of medical and surgical care. With the advent of next-generation technology to interrogate the microbiome at the level of its membership, community structure and production of metabolites, applying measures by which the gut microbiome can be manipulated to the advantage of both the patient and provider is now possible. Among the many proposed methods, the most practical and promising is dietary pre-habilitation of the gut microbiome prior to high-risk anastomotic surgery. In this review, we will outline the scientific rationale and molecular underpinning that support dietary pre-habilitation as a practical and deliverable method to prevent complications after high-risk anastomotic surgery.

Role of Damage-Associated Molecular Patterns (DAMPS) in the Postoperative Period after Colorectal Surgery

Anastomotic leakage (AL) is a defect of the intestinal wall at the anastomotic site and is one of the most severe complications in colorectal surgery. Previous studies have shown that the immune system response plays a significant role in the development of AL. In recent years, DAMPs (damage-associated molecular patterns) have been identified as cellular compounds with the ability to activate the immune system. The NLRP3 inflammasome plays an important role in the inflammatory responses which are mediated by DAMPs such as ATP, HSP proteins or uric acid crystals, when found in extracellular environments. Recent publications suggest that systemic concentration of DAMPs in patients with colorectal surgery may determine the inflammatory process and have a role in the occurrence of AL and other post-surgery complications. This review provides valuable knowledge about the current evidence supporting this hypothesis and highlights the possible role of these compounds in postoperative processes, which could open a new path to explore new strategies to prevent possible post-surgical complications.

The usefulness of indocyanine green fluorescence imaging for intestinal perfusion assessment of intracorporeal anastomosis in laparoscopic colon cancer surgery

PURPOSE

The purpose of this study was to clarify the usefulness of indocyanine green fluorescence imaging (ICG-FI) in the assessment of intestinal vascular perfusion in patients who receive intracorporeal anastomosis (IA) in colon cancer surgery.

METHODS

This was a single-center, retrospective study using propensity score matching. We compared the surgical outcomes of colon cancer patients who underwent laparoscopic colonic resection with IA or external anastomosis (EA) with the intraoperative evaluation of anastomotic perfusion using ICG-FI from January 2019 to July 2021. The detection rate of poor anastomotic perfusion by ICG-FI was examined.

RESULTS

A total of 223 patients were enrolled. After matching, 69 patients each were classified into the IA and EA groups. There were no significant differences in age, sex, body mass index, tumor localization, or progression between the two groups. The operation time was similar (172 min vs. 171 min, p = 0.62) and the amount of bleeding was significantly lower (0 ml vs. 2 ml, p = 0.0023) in the IA group. The complication rates (grade ≥ 2) of the two groups were similar (14.5% vs. 11.6%, p = 0.59). ICG-FI identified four patients (5.8%) with poor anastomotic perfusion in the IA group, but none in the EA group (p = 0.046). All four patients with poor perfusion in the IA group underwent additional resection; none of these patients developed postoperative complications.

CONCLUSION

Poor anastomotic perfusion was detected in 5.8% of cases who underwent laparoscopic colon cancer surgery with IA. ICG-FI is useful for evaluating anastomotic perfusion in IA in order to prevent AL.

A nomogram to predict the risk of colorectal anastomotic leakage combining inflammatory-nutritional and abdominal aorta calcium index

Background

Anastomotic leakage is a serious complication after colorectal cancer surgery, which affects the quality of life and the prognosis. This study aims to create a novel nomogram to predict the risk of anastomotic leakage for patients with colorectal cancer based on the preoperative inflammatory-nutritional index and abdominal aorta calcium index.

Methods

292 patients at Tianjin Medical University General Hospital (Tianjin, China) from January 2018 to October 2021 who underwent colorectal cancer surgery with a primary anastomosis were retrospectively reviewed. A nomogram was constructed based on the results of multivariate logistic regression model. The calibration curves and receiver operating characteristic curves were used to verify the efficacy of the nomogram.

Results

Univariate and multivariate analyses showed that tumor location (P = 0.002), preoperative albumin (P = 0.006), preoperative lymphocyte (P = 0.035), preoperative neutrophil to lymphocyte ratio (P = 0.024), and superior mesenteric artery calcium volumes score (P = 0.004) were identified as the independent risk factors for postoperative anastomotic leakage in patients with colorectal carcinoma. A nomogram was constructed based on the results of the multivariate analysis, and the C-index of the calibration curves was 0.913 (95%CI: 0.870-0.957) in the training cohort and 0.840 (95%CI: 0.753-0.927) in the validation cohort.

Conclusion

The nomogram, combining basic variables, inflammatory-nutritional index and abdominal aorta calcium index, could effectively predict the possibility of postoperative anastomotic leakage for patients with colorectal cancer, which could guide surgeons to carry out the appropriate treatment for the prevention of anastomotic leakage.

Applying interpretable machine learning algorithms to predict risk factors for permanent stoma in patients after TME

Objective

The purpose of this study was to develop a machine learning model to identify preoperative and intraoperative high-risk factors and to predict the occurrence of permanent stoma in patients after total mesorectal excision (TME).

Methods

A total of 1,163 patients with rectal cancer were included in the study, including 142 patients with permanent stoma. We collected 24 characteristic variables, including patient demographic characteristics, basic medical history, preoperative examination characteristics, type of surgery, and intraoperative information. Four machine learning algorithms including extreme gradient boosting (XGBoost), random forest (RF), support vector machine (SVM) and k-nearest neighbor algorithm (KNN) were applied to construct the model and evaluate the model using k-fold cross validation method, ROC curve, calibration curve, decision curve analysis (DCA) and external validation.

Results

The XGBoost algorithm showed the best performance among the four prediction models. The ROC curve results showed that XGBoost had a high predictive accuracy with an AUC value of 0.987 in the training set and 0.963 in the validation set. The k-fold cross-validation method was used for internal validation, and the XGBoost model was stable. The calibration curves showed high predictive power of the XGBoost model. DCA curves showed higher benefit rates for patients who received interventional treatment under the XGBoost model. The AUC value for the external validation set was 0.89, indicating that the XGBoost prediction model has good extrapolation.

Conclusion

The prediction model for permanent stoma in patients with rectal cancer derived from the XGBoost machine learning algorithm in this study has high prediction accuracy and clinical utility.

Fusobacterium nucleatum induces colon anastomosis leak by activating epithelial cells to express MMP9

Background

Despite advances in anastomotic techniques and perioperative care, the incidence of anastomotic leak (AL) has not substantially decreased over time. Although it is known that AL etiology is multifactorial and the mechanisms involved remain unclear, there is accumulating evidence pointing at AL related to gut microbiota.

Method

We firstly performed a clinical study to analyze the gut microbiota between colorectal cancer patients who developed AL and those who did not (nAL) using 16S-rRNA sequencing and quantitative real-time PCR to identify AL risk bacterial taxa. Then we built a rat anastomosis model and performed a bacteria transplantation to ensure the cause-effect relationship. The anastomotic healing score was used to evaluate the healing of anastomosis. In addition, we assessed the adhesion ability of bacteria by staining with fluorescein isothiocyanate and attachment assay. The expression of matrix metalloproteinase 9 (MMP9) was detected by western blot, and the activity was detected by gelatin zymography.

Results

We found that the abundance and positive rate of Fusobacterium nucleatum (Fn) were higher in the AL patients. Exposure of the rat's colon anastomosis to Fn contributes to the loss of submucosa collagen I and III, leading to AL's pathogenesis. Fn can attach to the gut epithelial cells and stimulate intestinal MMP9 expression in vitro and in vivo. We further confirmed that these effects of Fn depended on the E-cadherin/β-catenin signaling pathway.

Conclusion

This work demonstrates that Fn attaches and then stimulates the expression of epithelial cells MMP9 by the E-cadherin/β-catenin signaling pathway. These effects contribute to collagen break down in the intestinal tissue, finally leading to AL.

Modular stimuli-responsive hydrogel sealants for early gastrointestinal leak detection and containment

Millions of patients every year undergo gastrointestinal surgery. While often lifesaving, sutured and stapled reconnections leak in around 10% of cases. Currently, surgeons rely on the monitoring of surrogate markers and clinical symptoms, which often lack sensitivity and specificity, hence only offering late-stage detection of fully developed leaks. Here, we present a holistic solution in the form of a modular, intelligent suture support sealant patch capable of containing and detecting leaks early. The pH and/or enzyme-responsive triggerable sensing elements can be read out by point-of-need ultrasound imaging. We demonstrate reliable detection of the breaching of sutures, in as little as 3 hours in intestinal leak scenarios and 15 minutes in gastric leak conditions. This technology paves the way for next-generation suture support materials that seal and offer disambiguation in cases of anastomotic leaks based on point-of-need monitoring, without reliance on complex electronics or bulky (bio)electronic implantables.

Anastomotic Rings and Inflammation Values as Biomarkers for Leakage of Stapled Circular Colorectal Anastomoses

Reliable markers to predict or diagnose anastomotic leakage (AL) of stapled circular anastomoses following colorectal resections are an important clinical need. Here, we aim to quantitatively investigate the morphology of anastomotic rings as an early available prognostic marker for AL and compare them to established inflammatory markers. We perform a prospective single-center cohort study, including patients undergoing stapled circular anastomosis between August 2020 and August 2021. The predictive value of the anastomotic ring configuration and the neutrophil-to-lymphocyte ratio (NLR) regarding anastomotic leakage is examined by ROC analyses and compared to the C-reactive protein (CRP) as an established marker. We included 204 patients, of which 19 suffered from anastomotic leakage (LEAK group), while in 185 patients the anastomoses healed well (HEAL group). The minimal height of the anastomotic rings as a binary classifier had a good ROC-AUC of 0.81 but was inferior to the NLR at postoperative day (POD) 5, with an excellent ROC-AUC of 0.93. Still, it was superior to the NLR at POD 3 (0.74) and the CRP at POD 3 (ROC-AUC 0.54) and 5 (ROC-AUC 0.70). The minimal height of the anastomotic rings as indicator for technically insufficient anastomoses is a good predictor of AL, while postoperatively the NLR was superior to the CRP in prediction of AL.

Novel surgical procedure for preventing anastomotic leakage following colorectal cancer surgery: A propensity score matching study

Hypoperfusion is the main cause of anastomotic leakage (AL) following colorectal surgery. The conventional method for evaluating anastomotic perfusion is to observe color change and active bleeding of the resection margin of the intestine and the pulsation of mesenteric vessels. However, the accuracy of this method is low, which may be due to insufficient observation time. A novel surgical procedure that separates the mesentery in advance at the intended transection site can delay the observation of anastomotic perfusion, and can potentially detect more anastomotic sites with insufficient vascular supply and reduce the rate of AL. This study aimed to investigate the effects of a novel surgical procedure on AL following sigmoid colon and rectal cancer surgeries. A total of 343 patients who underwent rectal and sigmoid colon cancer surgeries were included in the study. From August 2021 to June 2022, patients with sigmoid colon or rectal cancer underwent a new surgical procedure of pre-division of the mesentery (PDM) at the intended transection site (PDM group). Patients with colorectal cancer who underwent conventional surgical procedures from August 2018 to July 2021 were categorized as the non-PDM group. Symptomatic AL (SAL) within 30 days and other outcomes were retrospectively analyzed using propensity score matching and compared between the two groups. The incidences of SAL were 1.3% and 11.3% in the PDM and non-PDM groups, respectively. PDM significantly reduced the SAL rate in sigmoid colon and rectal cancer surgeries (P = 0.009). The incidence of total postoperative complications (P < 0.05) was significantly lower in the PDM group than that in the non-PDM group. There were no significant differences between the two groups for operative time (P = 0.662), intraoperative blood loss (P = 0.651), intraoperative blood transfusion (P = 0.316), and intensive care rate (P = 1). The length of postoperative hospital stay (P = 0.010) and first exhaust (P = 0.001) and defecation time (P < 0.05) were shorter in the PDM group than in the non-PDM group. PDM can effectively prevent AL, and this procedure can be safely performed in sigmoid colon and rectal cancer surgeries.

New understanding of gut microbiota and colorectal anastomosis leak: A collaborative review of the current concepts

Anastomotic leak (AL) is a life-threatening postoperative complication following colorectal surgery, which has not decreased over time. Until now, no specific risk factors or surgical technique could be targeted to improve anastomotic healing. In the past decade, gut microbiota dysbiosis has been recognized to contribute to AL, but the exact effects are still vague. In this context, interpretation of the mechanisms underlying how the gut microbiota contributes to AL is significant for improving patients' outcomes. This review concentrates on novel findings to explain how the gut microbiota of patients with AL are altered, how the AL-specific pathogen colonizes and is enriched on the anastomosis site, and how these pathogens conduct their tissue breakdown effects. We build up a framework between the gut microbiota and AL on three levels. Firstly, factors that shape the gut microbiota profiles in patients who developed AL after colorectal surgery include preoperative intervention and surgical factors. Secondly, AL-specific pathogenic or collagenase bacteria adhere to the intestinal mucosa and defend against host clearance, including the interaction between bacterial adhesion and host extracellular matrix (ECM), the biofilm formation, and the weakened host commercial bacterial resistance. Thirdly, we interpret the potential mechanisms of pathogen-induced poor anastomotic healing.

Value of different anastomoses in laparoscopic radical right hemicolectomy for right-sided colon cancer: retrospective study and literature review

Background

This study aimed to analyze the safety of circular lateral anastomosis and cross-lateral anastomosis in laparoscopic radical resection of right-sided colon cancer.

Methods

From January 2018 to March 2021, 147 patients with right-sided colon cancer were admitted to the Department of General Surgery, Cancer Hospital, Zhengzhou University. The experimental group comprised patients with circular lateral anastomosis, whereas the control group comprised patients with cruciform lateral anastomosis. The general clinical data, intraoperative features, and postoperative results of the two groups were compared and analyzed.

Results

Both groups successfully underwent laparoscopic lateral ileocolic anastomosis, with significant differences in anastomotic leakage (χ²=4.520, P < 0.05). By contrast, body mass index (t = 1.568, P = 0.119), histological typing (χ² = 2.067, P = 0.559), intraoperative bleeding (t = 0.418, P = 0.677), and intestinal obstruction (χ² = 2.564, P = 0.109) were not significantly different between the groups (P > 0.05).

Conclusions

In laparoscopic-assisted radical hemicolectomy for right-sided colon cancer, the incidence of postoperative anastomotic leakage was lower with circular lateral anastomosis than with cross-lateral anastomosis, and circular lateral anastomosis was superior to cross-lateral anastomosis in terms of reducing the length of hospital stay and improving patients' postoperative quality of life.

Efficacy of staple line reinforcement by barbed suture for preventing anastomotic leakage in laparoscopic rectal cancer surgery

BACKGROUND

Anastomotic leakage (AL) is a severe complication in rectal cancer surgery. Various methods, including intracorporeal reinforcing suturing, have been used to reduce the incidence of AL. However, little is known about the efficacy of staple-line reinforcement by barbed suture for preventing AL.

AIM

To evaluate the efficacy of staple-line reinforcement using barbed suture for preventing AL in laparoscopic surgery for rectal cancer.

METHODS

We retrospectively reviewed the clinical datum of 319 patients undergoing laparoscopic low anterior resection combined with double stapling technique between May 1, 2017 and January 31, 2021. All surgeries were performed by the same surgical team specializing in colorectal surgery. Patients were divided into two groups depending on whether they received reinforcing sutures. Patients’ baseline characteristics did not show any significant difference between the two groups. We analyzed patient-, tumor-, as well as surgery-related variables using univariate and multivariate logistic analyses.

RESULTS

There were 168 patients in the reinforcing suture group and 151 patients in the non-reinforcing suture group. AL occurred in 25 cases (7.8%). Its incidence was significantly higher in the non-reinforcing suture group than in the reinforcing suture group (4.8% vs 11.3%, P = 0.031). The multivariate analyses demonstrated that the tumor site, tumor size and presence of staple-line reinforcement were independent risk factors for AL. We divided these patients into two risk groups based on the combination of tumor site and tumor size. Patients without any risk factor were assigned to the low-risk group (n = 177), whereas those having one or two risk factors were assigned to the high-risk group (n = 142). In the high-risk group, the AL incidence considerably decreased in the reinforcing suture group compared with that in the non-reinforcing suture group (P = 0.038). Nonetheless, no significant difference was found in the low-risk group between the two groups.

CONCLUSION

Staple-line reinforcement by barbed suture may decrease the incidence of AL. A large-scale prospective randomized controlled trial is needed for evaluating the efficacy of staple-line reinforcement for preventing AL.

A novel colorectal anastomotic method in natural orifice specimen extraction surgery for colorectal cancer

PURPOSE

We introduced a novel colorectal anastomotic technique, double-angle anastomosis combined with the double stapling technique (DAA-DST), to simplify the anastomosis step during natural orifice specimen extraction surgery (NOSES) and compared its safety and effectiveness with purse string anastomosis combined with the double stapling technique (PSA-DST).

METHODS

Between January 2018 and March 2021, 63 patients with colorectal cancer underwent NOSES with DAA-DST or PSA-DST. We compared the perioperative and oncological outcomes between the groups.

RESULTS

There were no significant differences in the operation time, blood loss, time to first passage of flatus and excrement or hospital stay duration between PSA-DST and DAA-DST groups. The overall postoperative complication rates were similar (DAA-DST vs PSA-DST, 21.2% vs 26.7%, p = 0.78), including the rate of anastomotic leakage (6.1% vs 10%, p = 0.91). The rate of successful DAA-DST was higher than that of PSA-DST (100% vs 93.3%). The DAA-DST group had a lower rate of positive drain fluid culture than the PSA-DST group (18.2% vs 26.7% p = 0.61). Recurrence (3.01% vs 6.67%, p = 0.93) and metastasis rates (6.06% vs 6.67%, p = 0.98) were similar between the groups.

CONCLUSION

DAA-DST is a safe and effective procedure and can simplify the procedure of NOSES.

Role of transanal drainage tubes in preventing anastomotic leakage after low anterior resection: a meta-analysis of randomized controlled trials

BACKGROUND

The transanal drainage tube (TDT) is thought to reduce the incidence of anastomotic leakage (AL) in patients with low anterior resection (LAR). However, results from different clinical trials are inconsistent, although nearly all meta-analyses agree on the efficacy. In contrast to results of many previous studies, 2 recent independent randomized controlled trials (RCTs) suggest that the use of TDT does not prevent AL. We performed a meta-analysis including only RCTs to compare patients with TDTs vs. those without TDTs in terms of AL rate.

METHODS

A systematic literature search was performed in the PubMed, Embase, Cochrane Library databases, Clinicaltrials.gov and WHO/ICTRP from inception until February 14, 2022. RCTs that evaluated the role of TDTs in AL prevention in patients who underwent LAR for rectal cancer were included. A meta-analysis was performed according to Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) reporting guidelines. Data were extracted by two authors independently, and random-effects models were implemented. The main outcome was AL, and the secondary outcome was the grade of AL.

RESULTS

Three RCTs were included involving a total of 1115 participants (559 patients in the TDT group and 556 in the non-TDT group). No significant difference in the AL rate was detected (RR = 0.69, 95% confidence interval (CI) 0.42-1.15, p = 0.15, I² = 21%, very low certainty evidence). The incidence of grade C AL was possibly lower in the TDT group (RR = 0.33, 95% CI 0.11-1.01, p = 0.05, very low certainty evidence), while the rate of grade B AL was similar between the two groups (RR = 1.17, 95% CI 0.66-2.08, p = 0.59, very low certainty evidence).

CONCLUSIONS

The present meta-analysis suggests that TDTs are not effective in reducing the overall incidence of AL, but possibly have a potential benefit in reducing the occurrence of grade C AL in patients with LAR. Based on the current limited data and existing heterogeneity, the inclusion of larger populations and the identification of more uniform indications for TDT need to be addressed in future studies.

Anastomotic Leak Impact on Long-Term Survival after Right Colectomy for Cancer: A Propensity-Score-Matched Analysis

Our goal was to assess the impact of anastomotic leaks (ALs) on oncologic outcomes using a case-matched analysis. Patients undergoing right hemicolectomy for cancer between 2014 and 2018 were included. The main variables were the risk factor of anastomotic leak, overall survival and disease-free survival. Propensity score matching was performed according to the patient’s age, co-morbidities and TNM staging as well as the type of procedure. Oncologic outcomes were analyzed. We included 488 patients and performed final analysis on 69 patients. The AL rate was 4.71% (23 patients). Intrahospital mortality was significantly higher in the AL group, at 1.3% (6 of 465) vs. 8.7% (2 of 23), p = 0.05. Three-year overall survival (OS) in the non-AL group was higher, although the difference could not be considered significant (71.5% vs. 37.3%, p = 0.082); similarly, the likelihood for impaired 3-year progression-free survival (PFS) was lower, but the difference here could also not be considered significant (69.3% vs. 37.3%, p = 0.106). Age, advanced tumor stage, lymph node metastases and distant metastases were associated with higher probability of death or recurrence of disease. In contrast, minimally invasive surgery was associated with lower probability of death (HR (95% CI): 0.99 (0.14–0.72); p = 0.023) and recurrence of disease (HR (95% CI): 0.94 (0.13–0.68); p = 0.020). In an adjusted Cox regression analysis, AL, age and distant metastases were associated with poor long-term survival. Moreover, AL, age and distant metastases were associated with higher probability of recurrence of disease. Based on our results, AL is a significant factor for worse oncologic outcomes. Simple summary: we aimed to assess patients with anastomotic leaks following right hemicolectomy for cancer. These patients were matched to patients without leaks. Propensity score analysis demonstrated that anastomotic leak was a marker of worse oncologic outcomes.

VIVOSTAT ® SYSTEM AS A METHOD OF PREVENTING ANASTOMOTIC LEAKAGE FOLLOWING LOW ANTERIOR RECTAL RESECTION: CLINICAL CASE

Background: According to current literature, anastomosis leakage holds a leading position among all complications of colorectal surgery. A particular area of prevention of this complication in colorectal oncology is the research of the possibilities of using biological adhesive compounds as a universal biological and mechanical barrier to the spread of intraluminal microflora and tumor cells.

Clinical case: A 65-year-old patient (female) was hospitalized with a diagnosis of rectal cancer cT3cN1cM0 (stage III) after neoadjuvant chemoradiotherapy. Surgical treatment was performed: the laparoscopic low anterior resection of the rectum with expanded lymphodissection, protective loop ileostomy. The anastomosis was formed at a height of 4 cm from the anus. Intraoperatively, the anastomosis line was strengthened using the Vivostat R system product. The technology of on-site preparation and application of the compound is described in the paper.. The postoperative period passed without complications.

Conclusion: Due to the possible economic, oncological and postoperative advantages, the use of modern fibrin adhesive compositions is quite promising for introduction into surgical practice. It is required to conduct research aimed at studying the effectiveness of this method of preventing the leakage of colorectal anastomoses.

Application of Transurethral Prostate Resection Instrumentation for Treating Low Rectal Anastomotic Leakage: A Pilot Study

Purpose

To determine an accurate method of inspecting low anastomotic leakages and application of transurethral prostate resection instrumentation for treating low rectal anastomotic leakage.

Patients and Methods

Clinical data of eight patients treated for anastomotic leakage after rectal cancer surgery at Zhangye People’s Hospital (affiliated to Hexi University), from August 2019 to November 2021, were retrospectively analyzed. Transanal prostate resection instrumentation was used to assess the leakage and surrounding conditions. Using prostate resection instrumentation, the presacral and perirectal residual cavities were washed and removed, and indwelling suprapubic presacral, transanal presacral, and rectal drainage tubes were placed. Continuous presacral saline irrigation and drainage and open negative-pressure suction in the rectal cavity were performed until the patients’ fistula healed.

Results

Of the eight patients with anastomotic leakages, one had grade B and seven had grade C International Study Group of Rectal Cancer anastomotic leakage classifications following Dixon operation. Transanal prostate resection instrumentation showed that the leakage of the one patient with grade B was less than a third of the circumference of the anastomosis. Among the seven patients with grade C, one leakage was less than a third of the anastomotic circumference. One patient had complete separation of the anastomosis and one distal colon necrosis, which necessitated immediate descending colostomy. Conservative treatment was successful in six patients; the conservative overall cure rate was 75%, and the median healing time was 43 (21–68) days.

Conclusion

Transanal examination of rectal anastomotic leakage using prostate resection instrumentation is comprehensive, easy to perform, provides clear visualization, accurately guides catheter placement, and can be combined with continuous open negative-pressure drainage, which is a safe, convenient, and effective method for treating low rectal leakage.

Implantation of an Impedance Sensor for Early Detection of Gastrointestinal Anastomotic Leaks

INTRODUCTION

Accurate early diagnosis of a gastrointestinal anastomotic leak remains a challenge. When an anastomotic leak develops, the electrical properties of the tissue undergoing inflammatory processes change, resulting from the extravasation of inflammatory fluid and cellular infiltration. The method described here intends to provide a novel early anastomotic leak warning system based upon measurable changes in tissue impedance nearby an acute inflammatory process.

METHODS

A biodegradable Mg-alloy was compared with a nonabsorbable stainless steel (STS) electrode connected to a wireless recording system for impedance measurement. In vitro measurements were made in physiological solutions and small animal (eight mice) and large animal (eight pigs) models with an anastomotic leak simulated by an open colotomy. Measurements were made at 10 mm intervals from the open colon at baseline and up to 120 min comparing these with a sutured colonic wound and normal tissue.

RESULTS

In-vitro biodegradable magnesium electrode impedance evaluation showed good sensitivity to different media due to its environmental corrosion properties. The impedance of an acidic environment (1.06 ± 0.02 kΩ for citric acid) was twice that of phosphate-buffered saline (PBS) (0.64 ± 0.008 kΩ) with a distinction between Normal Saline (0.42 ± 0.013 kΩ) and PBS (0.64 ± 0.008 kΩ). This was in contrast to the performance characteristics of the control STS electrodes, where impedance in an acidic environment was lower than saline or PBS (citric acid:0.76 ± 0.01 kΩ versus PBS: 1.32 ± 0.014 kΩ). In a mouse model simulating an anastomotic leak, there was a significant increase in impedance after 120 min when compared with controls (99.7% increase versus 9.6% increase, respectively; P < 0.02). This effect was confirmed in a pig model when relative impedance measurements of the leak and control groups were compared (1.86 ± 0.46 versus 1.07 ± 0.02, respectively; P < 0.027).

CONCLUSIONS

Electrophysiological measurement shows diagnostic sensitivity for a gastrointestinal leak with potential clinical utility in the postoperative detection of early intra-abdominal sepsis. Further investigation of biodegradable tissue sensors capable of monitoring an early anastomotic leak is required.

Severe complications from anastomotic leakage after total mesorectal excision with the protective loop ileostomy in three patients

Introduction and importance

A protective loop ileostomy is recommended in ultra-low rectal cancer to reduce the complications associated with anastomotic leakage (AL), but there are few studies on the complications after AL. The purpose of this study was to outline our experience in the successful treatment of severe abdominal infection after AL in rectal cancer patients with the protective loop ileostomy.

Case presentation

In this report, we describe three cases of AL after standard total mesorectal excision with the protective loop ileostomy. Severe abdominal infection occurred postoperatively. The patients were successfully treated by surgical reintervention and had an uneventful recovery. No recurrence was observed after 2 years.

Clinical discussion

We consider that pelvic floor reconstruction and extending the extubation time should be performed in patients with a high risk of AL. Moreover, when severe abdominal infection and early infectious shock occur after AL, immediate reoperation should be performed to minimize the complication.

Conclusion

Protective loop ileostomy can't decrease the re-operation rate for patients with AL. We should take preventive measures during and after the operation, as well as early detection and early treatment.

•

The protective loop ileostomy sometimes can’t prevent severe complications for patients with anastomotic leakage after TME operation

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Severe abdominal infection needs operation immediately.

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Pelvic floor reconstruction and extending the extubation time can reduce reoperation rate

Does Preoperative Waiting Time Affect the Short-Term Outcomes and Prognosis of Colorectal Cancer Patients? A Retrospective Study from the West of China

PURPOSE

The purpose of this study is to analyze the effect of preoperative waiting time on the short-term outcomes and prognosis in colorectal cancer (CRC) patients.

METHODS

We retrospectively analyzed 3744 CRC patients who underwent primary CRC surgery at a single clinical medical center from Jan 2011 to Jan 2020. The baseline information, short-term outcomes, overall survival (OS), and disease-free survival (DFS) were compared among the short-waiting group, the intermediate-waiting group, and the long-waiting group.

RESULTS

A total of 3744 eligible CRC patients were enrolled for analysis. There were no significant differences in all of the baseline information and short-term outcomes among the three groups. In multivariate analysis, older age (OS: p=0.000, HR = 1.947, 95% CI = 1.631-2.324; DFS: p=0.000, HR = 1.693, 95% CI = 1.445-1.983), advanced clinical stage (OS: p=0.000, HR = 1.301, 95% CI = 1.161-1.457; DFS: p=0.000, HR = 1.262, 95% CI = 1.139-1.400), overall complications (OS: p=0.000, HR = 1.613, 95% CI = 1.303-1.895; DFS: p=0.000, HR = 1.560, 95% CI = 1.312-1.855), and major complications (OS: p=0.001, HR = 1.812, 95% CI = 1.338-2.945; DFS: p=0.006, HR = 1.647, 95% CI = 1.153-2.352) were independent factors of OS and DFS. In addition, no significant difference was found in all stages (OS, p=0.203; DFS, p=0.108), stage I (OS, p=0.419; DFS, p=0.579), stage II (OS, p=0.465; DFS, p=0.385), or stage III (OS, p=0.539; DFS, p=0.259) in terms of OS and DFS among the three groups.

CONCLUSION

Preoperative waiting time did not affect the short-term outcomes or prognosis in CRC patients.

Prophylactic endoluminal vacuum therapy after major gastrointestinal surgery: a systematic review

In the last decade, endoluminal vacuum therapy (eVAC) has emerged as an effective treatment for anastomotic leak (AL); however, little is known regarding its prophylactic use. In this systematic review we evaluated overall outcomes in patients undergoing major gastrointestinal surgery and treated with prophylactic eVAC. A systematic review of English articles on four electronic databases was performed according to the PRISMA statement up until January 2022. References of selected articles were manually screened to identify relevant missing papers. Primary endpoints were AL and mortality rates estimates. Secondary endpoints included analysis of eVAC-associated morbidity, treatment duration, long-term complications, and general indications for the eVAC management in the perioperative period. A total of 11 studies (5 case reports, 5 retrospective case series and a retrospective, case-control study) were included in the analysis. AL ranged from 0 to 25%. No major eVAC-associated complications were observed, except for sponge dislocation or obstruction. Overall mortality ranged between 0 and 12.5%; however, these fatalities were neither related to the use of eVAC, nor to AL-associated complications. The most frequent long-term complication was anastomotic stenosis responsive to endoscopic dilatation in most cases. The operating negative pressure ranged from -25 to -125 mmHg among different papers. In all studies but two, prophylactic eVAC was applied to anastomoses at high risk of dehiscence based on the subjective evaluation of the leading surgeon. In conclusion, prophylactic eVAC is safe and it could lead to potential benefit for prevention of AL, especially in high-risk anastomoses.

Stem cell therapy applied for digestive anastomosis: Current state and future perspectives

BACKGROUND

Digestive tract resections are usually followed by an anastomosis. Anastomotic leakage, normally due to failed healing, is the most feared complication in digestive surgery because it is associated with high morbidity and mortality. Despite technical and technological advances and focused research, its rates have remained almost unchanged the last decades. In the last two decades, stem cells (SCs) have been shown to enhance healing in animal and human studies; hence, SCs have emerged since 2008 as an alternative to improve anastomoses outcomes.

AIM

To summarise the published knowledge of SC utilisation as a preventative tool for hollow digestive viscera anastomotic or suture leaks.

METHODS

PubMed, Science Direct, Scopus and Cochrane searches were performed using the key words “anastomosis”, “colorectal/colonic anastomoses”, “anastomotic leak”, “stem cells”, “progenitor cells”, “cellular therapy” and “cell therapy” in order to identify relevant articles published in English and Spanish during the years of 2000 to 2021. Studies employing SCs, performing digestive anastomoses in hollow viscera or digestive perforation sutures and monitoring healing were finally included. Reference lists from the selected articles were reviewed to identify additional pertinent articles.

Given the great variability in the study designs, anastomotic models, interventions (SCs, doses and vehicles) and outcome measures, performing a reliable meta-analysis was considered impossible, so we present the studies, their results and limitations.

RESULTS

Eighteen preclinical studies and three review papers were identified; no clinical studies have been published and there are no registered clinical trials. Experimental studies, mainly in rat and porcine models and occasionally in very adverse conditions such as ischaemia or colitis, have been demonstrated SCs as safe and have shown some encouraging morphological, functional and even clinical results. Mesenchymal SCs are mostly employed, and delivery routes are mainly local injections and cell sheets followed by biosutures (sutures coated by SCs) or purely topical. As potential weaknesses, animal models need to be improved to make them more comparable and equivalent to clinical practice, and the SC isolation processes need to be standardised. There is notable heterogeneity in the studies, making them difficult to compare. Further investigations are needed to establish the indications, the administration system, potential adjuvants, the final efficacy and to confirm safety and exclude definitively oncological concerns.

CONCLUSION

The future role of SC therapy to induce healing processes in digestive anastomoses/sutures still needs to be determined and seems to be currently far from clinical use.

Multispectral Imaging Using Fluorescent Properties of Indocyanine Green and Methylene Blue in Colorectal Surgery-Initial Experience

Introduction: Image-guided surgery is becoming a new tool in colorectal surgery. Intraoperative visualisation of different structures using fluorophores helps during various steps of operations. In our report, we used two fluorophores—indocyanine green (ICG), and methylene blue (MB)—during different steps of colorectal surgery, using one camera system for two separate near-infrared wavelengths. Material and methods: Twelve patients who underwent complex open or laparoscopic colorectal surgeries were enrolled. Intravenous injections of MB and ICG at different time points were administered. Visualisation of intraoperative ureter position and fluorescent angiography for optimal anastomosis was performed. A retrospective analysis of patients treated in our departments during 2020 was performed, and data about ureter injury and anastomotic site complications were collected. Results: Intraoperative localisation of ureters with MB under fluorescent light was possible in 11 patients. The mean signal-to-background ratio was 1.58 ± 0.71. Fluorescent angiography before performing anastomosis using ICG was successful in all 12 patients, and none required a change in position of the planned colon resection for anastomosis. The median signal-to-background ratios was 1.25 (IQR: 1.22–1.89). Across both centres, iatrogenic injury of the ureter was found in 0.4% of cases, and complications associated with anastomosis was found in 5.5% of cases. Conclusions: Our study showed a substantial opportunity for using two different fluorophores in colorectal surgery, whereby the visualisation of one will not change the possible quantification analysis of the other. Using two separate dyes during one procedure may help in optimisation of the fluorescent properties of both dyes when using them for different applications. Visualisation of different structures by different fluorophores seems to be the future of image-guided surgery, and shows progress in optical technologies used in image-guided surgery.

The natural orifice specimen extraction surgery compared with conventional laparoscopy for colorectal cancer: A meta-analysis of efficacy and long-term oncological outcomes

PURPOSE

Natural orifice specimen extraction surgery (NOSES) has gradually become established in treating colorectal cancer. This meta-analysis assesses NOSES in the treatment of colorectal cancer compared with conventional laparoscopy (CL) and determines the effect of long-term prognosis.

METHODS

Various medical databases were searched up to May 2021. We included retrospective and randomized trials on the treatment of colorectal cancer with NOSES. Pooled weighted/standardized mean differences (WMD/SMD), odds ratios (OR) and hazard ratios (HR) with 95% confidence intervals (CIs) were calculated using either fixed- or random-effects models. STATA was conducted for the meta-analysis.

RESULTS

This meta-analysis included 16 studies comprising 2266 patients. Compared with CL, NOSES had more benefits in terms of overall postoperative complications (OR = 0.47, 95%CI [0.35,0.64]; Z = 4.91, P < 0.001), incision-related complications (OR = 0.15, 95%CI [0.07,0.31]; Z = 4.97, P < 0.001), time to first flatus (SMD = -0.58, 95%CI [-0.68,-0.48]; Z = 11.21, P < 0.001), hospital stay (WMD = -1.03, 95%CI [-1.55,-0.51]; Z = 3.86, P < 0.001), cosmetic scores (WMD = 1.37, 95%CI [0.59,2.14]; Z = 3.47, P = 0.001), the visual analogue scale on postoperative day 1（WMD = -1.46, 95%CI [-2.39,-0.52]; Z = 3.06, P = 0.002), additional analgesics usage (OR = 0.33, 95%CI [0.26, 0.43]; Z = 8.43, P < 0.001), whereas the operative time of NOSES was prolonged (WMD = 13.09, 95%CI [7.07,19.11]; Z = 4.26, P < 0.001). Postoperative anastomotic complications, intra-abdominal infection, pelvic floor function, intraoperative blood loss, number of lymph node dissection, 3-year disease-free and overall survival in the NOSES group were comparable with those in the CL group.

CONCLUSIONS

NOSES is a safe and reliable surgical procedure for the treatment of colorectal cancer and provides good long-term oncological outcomes. Large-scale multicenter studies are required to confirm its clinical benefits.

Anastomotic Leak: Toward an Understanding of Its Root Causes

BACKGROUND

When an anastomotic leak is discussed at a typical surgical morbidity and mortality conference, it is often presented as a due to an error in surgical technique involving ischemia, tension, or device failure. Here we assert that without direct visual analysis of the leak site and its tissue histology, an ex post facto claim that an anastomotic leak is due to an error in surgical technique remains speculative.

METHODS

The arguments and rationale used to conclude that an anastomotic leak is due to an error in surgical technique are critically reviewed and assessed for their validity.

RESULTS

No case series or literature exists in which a root cause analysis has been carried out with visual and tissue level evidence to determine the root cause(s) of an anastomotic leak.

CONCLUSIONS

At the individual case level, declaring that an anastomotic leak is due to an error in surgical technique without clear and compelling evidence either visually and/or at the tissue level to substantiate such a claim remains speculative.

C-reactive protein level on postoperative day 3 as a predictor of anastomotic leakage after elective right-sided colectomy

PURPOSE

To investigate the factors predictive of anastomotic leakage in patients undergoing elective right-sided colectomy.

METHODS

The subjects of this retrospective study were 247 patients who underwent elective right hemicolectomy or ileocecal resection with ileocolic anastomosis between April 2012 and March 2019, at our institution.

RESULTS

Anastomotic leakage occurred in 9 of the 247 patients (3.6%) and was diagnosed on median postoperative day (POD) 7 (range POD 3-12). There were no significant differences in the background factors or preoperative laboratory data between the patients with anastomotic leakage (anastomotic leakage group) and those without anastomotic leakage (no anastomotic leakage group). Open surgery was significantly more common than laparoscopic surgery (P = 0.027), and end-to-side anastomosis was less common (P = 0.025) in the anastomotic leakage group. The C-reactive protein (CRP) level in the anastomotic leakage group was higher than that in the no anastomotic leakage group on PODs 3 (P < 0.001) and 5 (P < 0.001). ROC curve analysis revealed that anastomotic leakage was significantly more frequent in patients with a serum CRP level ≥ 11.8 mg/dL [area under the curve (AUC) 0.83].

CONCLUSION

A serum CRP level ≥ 11.8 mg/dL on POD 3 was predictive of anastomotic leakage being detected on median POD 7.

Dynamic Serosal Perfusion Assessment during Colorectal Resection Using Visible Light Spectroscopy

INTRODUCTION

Anastomotic leakage (AL) in colorectal surgery occurs with an incidence of up to 20%. Bowel perfusion is deemed to be one of the most important factors for anastomotic healing. However, not much is known about its variability during colorectal surgery and its impact on the outcome. Therefore, this study aims to evaluate serosal oxygen saturation patterns during colorectal resections with visible light spectroscopy (VLS).

MATERIALS AND METHODS

Bowel perfusion in patients undergoing left-sided colorectal resections was assessed at different timepoints during surgery using VLS on the colonic serosa. The primary outcome parameter was serosal oxygen saturation (StO2) at the anastomosis during different timepoints of surgery.

RESULTS

We included 50 patients who underwent colorectal resection for bowel cancer (58%) and diverticular disease (34%). StO2 at the proximal site of the anastomosis increased significantly throughout the surgery (mean difference 3.61%; 95% CI -6.22 to -1.00; p = 0.008). However, aberrancy from this identified perfusion pattern had no impact on the postoperative outcome.

CONCLUSION

During colorectal resections, we could demonstrate an increase of the colonic StO2 throughout surgery. Appearance of AL was not associated with lower StO2, underlining the multifactorial genesis of developing AL.

Safe Anastomoses without Ostomies in Cytoreductive Surgery with Heated Intraperitoneal Chemotherapy: Technical Considerations and Modifications

BACKGROUND

Gastrointestinal complications, predominantly anastomotic leak (AL), are the most frequent source of severe morbidity after cytoreductive surgery (CRS).

OBJECTIVE

The aim of this study was to present the technical standards for colorectal anastomoses developed and systematically applied to all patients undergoing CRS in a high-volume tertiary center, and the associated AL rates.

METHODS

This was a descriptive study reporting the technical characteristics of a standardized protocol for three types of colorectal anastomoses (colorectal, ileorectal, and ileocolic) in CRS with heated intraperitoneal chemotherapy (HIPEC), and a retrospective analysis of prospectively collected data on anastomotic outcomes. All patients (1172) undergoing CRS with HIPEC from September 2006 to September 2020 were included. The anastomotic complications were classified according to the International Study Group of Rectal Cancer Surgery (ISGRCS) classification.

RESULTS

Overall, 1172 patients underwent 1300 procedures and 1359 gastrointestinal anastomoses. An ileocolic anastomosis was performed in 408 patients, colorectal anastomosis in 469 patients, and ileorectal anastomosis in 16 patients, none with diverting ileostomy; 345 other gastrointestinal reconstructions and 82 urinary reconstructions were performed in these patients. The AL rate was 1% (4/408) for the ileocolic anastomosis, 0.85% (4/469) for the colorectal anastomosis, and 0% (0/16) for the ileorectal anastomosis. One patient died postoperatively due to AL.

CONCLUSIONS

Systematic application of standardized techniques adapted to ensure optimal tissue healing (stapled anastomoses avoiding overlap, accurate staple deployment, and hand-sewn reinforcement) are associated with a very high level of anastomotic safety in a large cohort of patients undergoing CRS and HIPEC.

Hypocalcemia: A possible risk factor for anastomotic leak in digestive surgery

Anastomotic leaks (ALs) remain the most severe complication in digestive surgery, as well as the most consumptive in terms of human and financial resources. There is an abundance of international research which has focused on identifying and correcting risk factors, and on individualized surgical management as well. The most frequent risk factors are male sex, obesity, diabetes, advanced malignant disease, ASA score, perioperative blood loss or perioperative transfusion, long operation time, emergency operation and altered nutritional status. The aim of the present study was to measure the preoperative serum calcium level and to find a possible correlation between calcium levels and the risk of AL occurrence. A retrospective analysis of medical records for 122 patients who underwent surgical gut resection with anastomosis for different pathologies was carried out. Preoperative serum calcium level and the occurrence of AL was noted. The results revealed that the average value of total blood calcium was 8.78 mg/dl, without a significant difference in sex groups. Hypocalcemia was identified in 44 patients (36.1%). AL was identified in 8 patients (6.6%), with a statistically insignificant difference between male and female patients. The average value of blood calcium in the AL patient group was 8.07 mg/dl, while in patients without AL the average value was 8.83 mg/dl. Hypocalcemia, defined as a serum calcium level below 8.5 mg/dl, was observed in 7 of the 8 patients presenting with AL (87.5%) and 37 patients who did not present with AL (32.5%), a significant difference with which to consider and include hypocalcemia in the group of risk factors for AL (P=0.001). In conclusion, preoperative low serum calcium level can represent a risk factor for AL in digestive surgery.

Intestinal Microbiota in Colorectal Cancer Surgery

Simple Summary

The microbial communities of the intestine exist in a delicate balance with the human. Colorectal cancer is one of the most common gastrointestinal malignancies, and the microbiota seems to be related to it. The intestinal microbiota of patients after colorectal surgery is changed due to surgical stress and other perioperative factors. The occurrence of complications after colorectal cancer (CRC) surgery may depend on these bacterial shifts, which could also be associated with prognosis and survival in postoperative CRC patients.

Abstract

The intestinal microbiota consists of numerous microbial species that collectively interact with the host, playing a crucial role in health and disease. Colorectal cancer is well-known to be related to dysbiotic alterations in intestinal microbiota. It is evident that the microbiota is significantly affected by colorectal surgery in combination with the various perioperative interventions, mainly mechanical bowel preparation and antibiotic prophylaxis. The altered postoperative composition of intestinal microbiota could lead to an enhanced virulence, proliferation of pathogens, and diminishment of beneficial microorganisms resulting in severe complications including anastomotic leakage and surgical site infections. Moreover, the intestinal microbiota could be utilized as a possible biomarker in predicting long-term outcomes after surgical CRC treatment. Understanding the underlying mechanisms of these interactions will further support the establishment of genomic mapping of intestinal microbiota in the management of patients undergoing CRC surgery.

IMARI: multi-Interventional program for prevention and early Management of Anastomotic leakage after low anterior resection in Rectal cancer patIents: rationale and study protocol

Background

Anastomotic leakage (AL) is still a common and feared complication after low anterior resection (LAR) for rectal cancer. The multifactorial pathophysiology of AL and lack of standardised treatment options requires a multi-modal approach to improve long-term anastomotic integrity. The objective of the IMARI-trial is to determine whether the one-year anastomotic integrity rate in patients undergoing LAR for rectal cancer can be improved using a multi-interventional program.

Methods

IMARI is a multicentre prospective clinical effectiveness trial, whereby current local practice (control cohort) will be evaluated, and subsequently compared to results after implementation of the multi-interventional program (intervention cohort). Patients undergoing LAR for rectal cancer will be included. The multi-interventional program includes three preventive interventions (mechanical bowel preparation with oral antibiotics, tailored full splenic flexure mobilization and intraoperative fluorescence angiography using indocyanine green) combined with a standardised pathway for early detection and active management of AL. The primary outcome is anastomotic integrity, confirmed by CT-scan at one year postoperatively. Secondary outcomes include incidence of AL, protocol compliance and association with AL, temporary and permanent stoma rate, reintervention rate, quality of life and functional outcome. Microbiome analysis will be conducted to investigate the role of the rectal microbiome in AL.

In a Dutch nationwide study, the AL rate was 20%, with anastomotic integrity of 90% after one year. Based on an expected reduction of AL due to the preventive approaches of 50%, and increase of anastomotic integrity by a standardised pathway for early detection and active management of AL, we hypothesised that the anastomotic integrity rate will increase from 90 to 97% at one year. An improvement of 7% in anastomotic integrity at one year was considered clinically relevant. A total number of 488 patients (244 per cohort) are needed to detect this difference, with 80% statistical power.

Discussion

The IMARI-trial is designed to evaluate whether a multi-interventional program can improve long-term anastomotic integrity after rectal cancer surgery. The uniqueness of IMARI lies in the multi-modal design that addresses the multifactorial pathophysiology for prevention, and a standardised pathway for early detection and active treatment of AL.

Trial registration

Trialregister.nl (NL8261), January 2020.