Management of anastomotic leakage after rectal surgery: a review article

Anastomotic tension "Bridging": a risk factor for anastomotic leakage following low anterior resection

BACKGROUND

Excessive tension at the anastomosis contributes to anastomotic leakage (AL) in low anterior resection (LAR). However, the specific tension has not been measured. We assessed whether "Bridging," characterized by the proximal colon resembling a suspension bridge above the pelvic floor, is a significant risk factor for AL following LAR for rectal cancer.

METHODS

This retrospective study reviewed the medical records and laparoscopic videos of 102 patients who underwent laparoscopic LAR using the double stapling technique at Yachiyo Hospital between January 2014 and December 2023. Patients were classified based on whether they had Bridging (tight or sagging) or were in a Resting state of the proximal colon, and the association between Bridging and AL was examined.

RESULTS

AL occurred in 31.3% of the Tight Bridging group, 20% of the Sagging Bridging group, and 2.2% of the Resting group (P = 0.002). The incidence of AL was significantly higher in patients with Bridging than in those without (23.2% vs. 2.2%, P = 0.003). Multivariate analysis revealed that Bridging is an independent risk factor for AL (odds ratio = 6.97; 95% confidence interval: 1.45-33.6; P = 0.016).

CONCLUSIONS

The presence of Bridging is a significant risk factor for AL following LAR for rectal cancer, suggesting the need for implementing preventive measures in patients with this condition.

Virtual Monoenergetic Images Facilitate Better Identification of the Arc of Riolan During Splenic Flexure Takedown

OBJECTIVE

This study aimed to investigate whether virtual monoenergetic images (VMIs) can aid radiologists and surgeons in better identifying the arc of Riolan (AOR) and to determine the optimal kilo electron volt (keV) level.

METHODS

Thirty-three patients were included. Conventional images (CIs) and VMI (40-100 keV) were reconstructed using arterial phase spectral-based images. The computed tomography (CT) attenuation and noise of the AOR, the CT attenuation of the erector spinal muscle, and the background noise on VMI and CI were measured, respectively. The signal-to-noise ratio, contrast-to-noise ratio (CNR), and signal intensity ratio were calculated. The image quality of the AOR was evaluated according to a 4-point Likert grade.

RESULTS

The CT attenuation, noise, CNR, and signal intensity ratio of the AOR were significantly higher in VMI at 40 and 50 keV compared with CI ( P < 0.001); VMI at 40 keV was significantly higher than 50 keV ( P < 0.05). No significant difference in signal-to-noise ratio, background noise, and CT attenuation of the spinal erector muscle was observed between VMI and CI ( P > 0.05). virtual monoenergetic image at 40 keV produced the best subjective scores.

CONCLUSIONS

Virtual monoenergetic image at 40 keV makes it easier to observe the AOR with optimized subjective and objective image quality. This may prompt radiologists and surgeons to actively search for it and encourage surgeons to preserve it during splenic flexure takedown.

Impact of Circular Stapler Size on the Risk of Anastomotic Complications in Patients With Left-sided Colorectal Cancer: A Propensity Score-matched Study

Background/Aim

The present study examined the impact of circular stapler size on anastomotic complications, including leakage and stricture in patients undergoing double-stapling technique (DST) anastomosis for left-sided colon or rectal cancer.

Patients and Methods

A total of 403 patients were enrolled in this study, with circular stapler sizes  of 25, 28, and 29 mm.

Results

A small circular stapler (25 mm) was used in 170 cases (42.2%), and a medium-sized circular stapler (28/29 mm) was used in 233 cases (57.8%). After propensity score matching, there was no marked difference in the incidence of anastomotic leakage/stricture between the groups (13.9% vs. 10.9%, 3.0% vs. 1.0%, respectively).

Conclusion

The size of the circular stapler was not associated with the incidence of anastomotic leakage or stricture in this cohort.

Risk factors of anastomotic leak in colorectal cancer: a multicentric study in a Latin American country

Introduction

The anastomotic leak (AL) is one of the most feared complications of colorectal surgery, since it is associated with a high rate of morbidity, mortality, length of hospital stay and cost of care. Our aim was to determine the risk factors associated with anastomosis leak in colorectal cancer patients who underwent surgical resection with anastomosis.

Methods

A multicentre observational, analytical, retrospective and case-control study was carried out. For each case, two controls were included from three national hospitals from Lima, Peru during the period 2021-2022. To determine the degree of association, multivariate logistic regression model was carried out.

Results

A total of 360 patients were included, 120 from each hospital. The mean age of the population was 68.03 ± 14.21 years old. The majority were 65 years old or older (66.1%), 52.8% were female, and 63.3% had clinical stage III. The 40% of the patients had albumin levels lower than 3.5 g/dL. Regarding the surgery, 96.4% were elective, 68.9% underwent open approach, and 80.8% had an operative time of more than 180 minutes. Most of them had right colon cancer (50.8%). In the multivariate analysis, a significant association was found with the age variable (OR = 2.48; 95%CI:1.24-4.97), clinical tumour level (OR = 2.71; 95%CI:1.34-5.48), American Society of Anesthesiologists (ASA) Score (OR = 3.23; 95%CI:1.10-9.50), preoperative serum albumin (OR = 22.2; 95%CI:11.5-42.9).

Conclusion

The most important independent risk factors associated with AL among patients with colorectal cancer were pre-operative such as lower preoperative serum albumin levels, followed by a higher ASA Score, clinical-stage III-IV, and an age ≥65 years old.

Anastomotic Leakage after Colorectal Surgery: Risk Factors, Diagnosis and Therapeutic Options

Anastomotic leakage (AL) is the most severe and devastating complication of colorectal surgery. The objectives of this study were to identify the risk factors involved in the development of AL, evaluate diagnostic methods and explore therapeutic options in case of colorectal cancer surgery.

MATERIAL AND METHODS

we conducted a retrospective study on 28 AL recorded after 315 elective colorectal cancer surgeries performed in 1st Surgery Clinic of Craiova over an 8-year period (2014-2022).

RESULTS

The overall incidence of AL was 8.88%. The identified risk factors were rectal cancer (22.38%), low anterior rectal resection (50%), open approach, advanced age (82.15% over 60 years old), male sex (3:1), and the presence of two or more co-morbidities. Medical conservative treatment was the primary line of treatment in all cases. Leakage closure was achieved in 22 cases (78.56%), with exclusive conservative treatment in 15 cases (46.42%) and combined conservative and surgical treatment in 7 cases (25.0%). Overall morbidity was recorded at 64.28%, with 8 cases of general evolving complications and 10 cases of local complications. General mortality was reported at 6 (21.42%), with 3 (16.66%) occurring after conservative treatment and 3 after re-interventions (30%).

CONCLUSIONS

our study identified advanced age, the presence of two or more co-morbidities, male sex, rectal surgery, and neoadjuvant chemoradiation as the most important risk factors for AL. Medical conservative treatment was the primary treatment modality, while reoperation was necessary in cases of uncontrollable sepsis and MODS. Mortality after re-intervention was nearly double compared to conservative treatment.

Specific Septic Complications after Rectal Cancer Surgery: A Critical Multicentre Study

The postoperative septic complications in gastrointestinal surgery impact immediate as well as long-term outcomes, which lead to reinterventions and additional costs. The authors presented the experience of three surgery clinics in Romania regarding the specific septic complications occurring in patients operated on for rectal cancer. The study group comprised 2674 patients who underwent surgery over a 5-year period (2017-2021). Neoplasms of the middle and lower rectum (76%) were the majority. There were 85% rectal resections and 15% abdominoperineal excisions of the rectum. In total, 68.54% of patients were operated on laparoscopically, and 31.46% received open surgery. Without taking wound infections into account, 97 (3.67%) patients had abdominal-pelvic septic complications. The aim was to evaluate the causes of the complications. The percentage of suppurations after surgery of the rectum treated by radiochemotherapy was considerably higher than after surgery of the non-radiated upper rectum. The fatality rate was 5.15%. The risk of fistulas was significantly associated with the preoperative treatment, tumour position and type of intervention. Sex, age, TNM stage or grade were not significant at 0.05 the threshold. The risk of fistulas is reduced with low anterior resection, but the gravity of these complications is higher in the lower rectum compared with the superior rectum. Preoperative radiochemotherapy is a contributing factor to septic complications.

Risk Factors of Anastomotic Leakage After Anterior Resection for Rectal Cancer Patients

OBJECTIVE

Anastomotic leakage (AL) is one of the serious complications after anterior resection for rectal cancer. Defunctioning stoma (DS) is one of the most widely used approaches to prevent it; however, the effect of DS on the occurrence of AL remains controversial. This study aimed to investigate risk factors of AL and assess the effect of DS after anterior resection for rectal cancer patients.

METHODS

A retrospective analysis was conducted for the data of 1840 patients who underwent anterior resection for rectal cancer from January 2014 to December 2019.

RESULTS

The results showed the overall AL incidence was 7.5%. Multivariate analyses revealed that males [odds ratio (OR) 1.562] and T3-T4 stage (OR 1.729) were independent risk factors for all patients. After propensity score matching analysis, the AL incidence was 14.1% in the group with no DS and 6.4% in the DS group (P<0.001). The clinical AL (grade B + grade C) incidence was 12.4% in no DS group and 4.6% in the DS group (P<0.001).

CONCLUSION

The study suggested that males and T3-T4 stage were independent risk factors of AL. In addition, DS could reduce the rate of symptomatic AL.

Early postoperative endoscopic evaluation of rectal anastomoses: a prospective cross-sectional study

BACKGROUND

Reported incidence of anastomotic leakage (AL) of rectal anastomoses is up to 29% with an overall mortality up to 12%. Nevertheless, there is no uniform evidence-based diagnostic procedure for early detection of AL. The objective of this prospective clinical trial was to demonstrate the diagnostic value of early postoperative flexible endoscopy for rectal anastomosis evaluation.

METHODS

Flexible endoscopy between 5 and 8th postoperative day was performed consecutively in 90 asymptomatic patients. Sample size calculation was made using the two-stage Simon design. Diagnostic value was measured by management change after endoscopic evaluation. Anastomoses were categorized according to a new classification. Study is registered in German Clinical Trials Register (DRKS00019217).

RESULTS

Of the 90 anastomoses, 59 (65.6%) were unsuspicious. 20 (22.2%) were suspicious with partial fibrin plaques (n = 15), intramural hematoma and/or local blood coagulum (n = 4) and ischemic area in one. 17 of these anastomoses were treated conservatively under monitoring. In three a further endoscopic re-evaluation was performed and as consequence one patient underwent endoscopic vacuum therapy. 11 (12.2%) AL were detected. Here, two could be treated conservatively under monitoring, four with endoscopic vacuum therapy and five needed revision surgery. No intervention-related adverse events occurred. A change in postoperative management was made in 31 (34.4%) patients what caused a significant improvement of diagnosis of AL (p < 0.001).

CONCLUSIONS

Early postoperative endoscopic evaluation of rectal anastomoses is a safe procedure thus allows early detection of AL. Early treatment for suspicious anastomoses or AL could be adapted to avoid severe morbidity and mortality.

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.

All-cause 30- and 90-day inpatient readmission costs associated with 4 minimally invasive colon surgery approaches: A propensity-matched analysis using Medicare and commercial claims data

Background

The purpose of this study is to assess which minimally invasive colon surgery approach may be associated with the least 30- and 90-day inpatient readmission costs from a payer perspective.

Methods

This retrospective claims analysis included adult Medicare and commercially insured beneficiaries who underwent minimally invasive sigmoid, left, or right colon surgery between January 2016 and December 2019. Two cohorts were created based on the use of near-infrared fluorescence (NIF) and were propensity-score matched 1 NIF:5 NoNIF. Four subgroups were then created based on the presence of robotics (R): NIF-NoR, NIF-R, NoNIF-R, and NoNIF-NoR.

Results

A total of 50,148 patients were identified, of which 165 (0.3%) indicated the use of NIF and 49,983 (99.7%) did not. After propensity score matching, 990 patients were included (NIF cohort: 165; NoNIF cohort: 825). Of the 165 NIF patients, 87 were robotic-assisted and 78 were conventional laparoscopy. Of the 825 NoNIF patients, 136 were robotic-assisted and 689 were conventional laparoscopy. Postindex inpatient readmission costs were significantly different between the NIF and NoNIF cohorts with the NIF cohort having the lowest 30- and 90-day postindex readmission costs. Postindex readmission costs were also significantly different across the 4 subgroups at 30 and 90 days, with the NIF-NoR group having the lowest postindex readmission costs (all P < .05).

Conclusion

Using NIF without the robot during minimally invasive colon surgery is associated with the least 30- and 90-day inpatient readmission costs compared to the other 3 approaches. Hospitals may want to consider these potential cost savings when evaluating technologies for laparoscopic colon surgery.

Key Message

Near-infrared fluorescence (NIF) imaging without the robot during minimally invasive colon surgery may significantly save hospitals 30- and 90-day inpatient readmission costs compared to NIF with the robot, NoNIF with the robot, and NoNIF without the robot. This is important as hospitals may want to consider these cost findings in addition to capital equipment and disposable costs when evaluating technologies for laparoscopic colon surgery.

Intraoperative Colonic Irrigation for Low Rectal Resections With Primary Anastomosis: A Fail-Safe Surgical Model

Aim

Regardless the technological developments in surgery, the anastomotic leakage (AL) rate of low rectal anastomosis remains high. Though various perioperative protocols have been tested to reduce the risk for AL, there is no standard peri-operative management approach in rectal surgery. We aim to assess the short-term outcome of a multidisciplinary approach to reduce the rates of ALs using a fail-safe-model using preoperative and intraoperative colonic irrigation in low rectal resections with primary anastomosis.

Methods

Between January 2015 and December 2020, 92 patients received low rectal resections for rectal cancer with primary anastomosis and diverting ileostomy. All these patients received pre-operative mechanical bowel preparation (MBP) without antibiotics as well as intraoperative colonic irrigation. The intraoperative colonic irrigation was performed via the efferent loop of the ileostomy. All data were analyzed by SPSS for descriptive and inferential analyses.

Results

In the study period, 1.987 colorectal surgical procedures were performed. This study reports AL in 3 (3.3%) of 92 recruited patients. Other postoperative complications (Dindo-Clavien I-IV) were reported in 25 patients (27.2%), which occurred mainly due to non-surgical reasons such as renal dysfunction and sepsis. According to the fail-safe model, AL was treated by endoscopic or re-do surgery. The median postoperative length of hospitalization was 8 days (4–45) days.

Conclusion

This study validates the effectiveness of a multi-disciplinary fail-safe model with a pre-operative MBP and an intraoperative colonic irrigation in reducing AL rates. Intraoperative colonic irrigation is a feasible approach that lowers the AL rates by reducing fecal load and by decontamination of the colon and anastomotic region. Our study does not recommend a pre-operative administration of oral antibiotics for colorectal decontamination.

Redo surgery after low anterior resection for chronic pelvic sinus and anastomotic disruption. Could pull-through procedure with delayed anastomosis be a feasible alternative? Case reports and narrative review

Introduction

Case presentation

Discussion

Conclusion

•

Complications after colorectal anastomosis, such as septic leakage or anastomotic disruption, remain a problem to deal with for colorectal surgeons.

•

Conversion to terminal colostomy is the most frequent option chosen, but the most of time restoration of bowel continuity is not performed.

•

Delayed coloanal anastomosis with pull-through procedure described by Turnbull-Cutait might be an option to consider in difficult situations, to maintain or to restore intestinal continuity and could be also chosen as a first option for coloanal anastomosis.

Endoscopic Vacuum Therapy for Left-Sided Colorectal Anastomotic Leak Without Fecal Diversion

BACKGROUND

Endoscopic vacuum therapy for the treatment of rectal anastomotic leak has been shown to be effective and safe. The majority of patients are treated after fecal diversion to avoid further septic complications.

OBJECTIVE

To report the effectiveness of endoscopic vacuum therapy for rectal anastomotic leak without diversion compared to secondary stoma creation.

DESIGN

Retrospective cohort analysis.

SETTINGS

University hospital, single-center.

PATIENTS

Patients undergoing sigmoid or rectal resection without fecal diversion during primary surgery who were treated with endoscopic vacuum therapy for clinically relevant anastomotic leak.

MAIN OUTCOME MEASURES

Treatment success (sepsis control, granulation and closure of the leak cavity, and no subsequent interventional or surgical procedure required); treatment duration; complications associated with endoscopic vacuum therapy; outpatient treatment; and restoration of intestinal continuity in diverted patients.

RESULTS

Fifty-seven patients were included. In 20 patients (35%), endoscopic vacuum therapy was initiated without secondary diversion since the leak was extraperitoneal, and the sponge could be placed into the leak cavity with an adequate seal toward the lumen. In 18 patients (90%), this approach was successful. None of these patients required subsequent diversion in the further course of their disease. In two patients, secondary diversion was necessary due to treatment failure. Balloon dilatation for luminal stenosis was required in two patients. When comparing patient and treatment characteristics of patients with and without a stoma, including treatment success and duration, no significant differences were found. Restoration of intestinal continuity was achieved in 69% of diverted patients.

LIMITATIONS

Unrandomized, retrospective study design; confounding factors of treatment assignment; low patient numbers and short follow-up of diverted patients; and low statistical power.

CONCLUSION

In this single-institution study, endoscopic vacuum therapy for rectal anastomotic leak was successful in 90% of patients without diversion with regard to sepsis control, granulation of the leak cavity, avoidance of surgery, and long-term stoma-free survival. See Video Abstract at http://links.lww.com/DCR/B737.TERAPIA ENDOSCÓPICA POR ASPIRACIÓN AL VACÍO EN CASOS DE FUGA ANASTOMÓTICA RECTO-CÓLICA IZQUIERDA SIN OSTOMÍA DE PROTECCIÓNANTECEDENTES:Se ha demostrado que la terapia endoscópica por aspiración al vacío en casos de fuga anastomótica recto-cólica izquierda en el tratamiento de la fuga anastomótica rectal es eficaz y segura. La mayoría de los casos beneficiaron del tratamiento después de la confeción de un ostomía de protección para evitar más complicaciones sépticas.OBJETIVO:Demostrar la efectividad de la terapia endoscópica por aspiración al vacío en casos de fuga anastomótica recto-cólica izquierda sin ostomía de protección comparada con los casos que tuvieron la creación de una ostomía secundaria.DISEÑO:Análisis de cohortes de tipo retrospectivo.AJUSTE:Hospital universitario, unicéntrico.PACIENTES:Aquellos pacientes sometidos a una resección sigmoidea o rectal sin ostomía de protección durante una cirugía primaria, y que fueron tratados con terapia endoscópica por aspiración al vacío en caso de fuga anastomótica clínicamente relevante.PRINCIPALES MEDIDAS DE RESULTADO:Tratamiento exitoso (control de la sepsis, granulación y cierre de la cavidad de la fuga, sin requerir procedimiento quirúrgico o intervención ulteterior); duración del tratamiento; complicaciones asociadas con la terapia endoscópica por aspiración al vacío; tratamiento ambulatorio; restablecimiento de la continuidad intestinal en los pacientes portadores de ostomía.RESULTADOS:Se incluyeron 57 pacientes. En 20 pacientes (35%), se inició la terapia endoscópica por aspiración al vacío sin derivación secundaria, ya que la fuga era extraperitoneal y la esponja podía colocarse en la cavidad de la fuga con un sellado adecuado hacia el lumen. En 18 pacientes (90%), este enfoque fue exitoso. Ninguno de estos pacientes requirió una derivación posterior durante la evolución de la enfermedad. En dos pacientes, fue necesaria una derivación secundaria debido al fracaso del tratamiento. Se requirió dilatación con balón por estenosis luminal en dos pacientes. Al comparar las características de los pacientes y del tratamiento con y sin ostomía, incluido el éxito y la duración del tratamiento, no se encontraron diferencias significativas. El restablecimiento de la continuidad intestinal se logró en el 69% de los pacientes derivados.LIMITACIONES:Diseño de estudio retrospectivo no aleatorio; factores de confusión en la asignación del tratamiento; escaso número de pacientes y seguimiento a corto plazo de los pacientes ostomizados; bajo poder estadístico.CONCLUSIÓN:En este estudio de una sola institución, la terapia al vacío por vía endoscópica en casos de fuga anastomótica rectal fue exitosa en el 90% de los pacientes sin derivación con respecto al control de la sepsis, granulación de la cavidad de la fuga, como se evitó la cirugía y la sobrevida sin ostomía a largo plazo. Consulte Video Resumen en http://links.lww.com/DCR/B737. (Traducción-Dr. Xavier Delgadillo).

Impact of intraoperative colonoscopy on anastomotic leakage detection and prevention in colorectal anastomosis for rectal cancer

INTRODUCTION AND AIM

The value of leakage testing during colorectal resections to identify anastomotic leaks or bleeding has not been established. Our aim was to compare the impact of intraoperative colonoscopy (IOC) versus insufflation with a syringe, as leakage testing in lower anterior resection (LAR) for rectal cancer, with respect to the incidence of postoperative leakage (PL).

MATERIALS AND METHODS

A retrospective study utilizing a prospective database of 426 patients with rectal cancer that underwent elective LAR, within the time frame of January 2015 and December 2019, was conducted. The anastomotic leak test was chosen by the surgeon. The incidence of postoperative leakage was compared between patients that underwent IOC and those that had the syringe leak test, utilizing the logistic regression analysis. Propensity score matching was included.

RESULTS

There were no significant differences in the clinical characteristics or morbidity and mortality rates between the two groups. Four patients were excluded, leaving a patient total of 422. Seventy patients with IOC were compared with 352 that had the syringe leak test. The incidence of postoperative leakage was 5.7% in the IOC group and 12.2% in the control group (p = 0.001). After propensity score matching (n = 221), balancing the characteristics between the groups, the incidence of postoperative leakage was 5.7% in the IOC group and 13.9% in the syringe leak test group (p = 0.001).

CONCLUSION

IOC was shown to be a safe method for evaluating the integrity of colorectal anastomosis and was associated with a higher percentage of protective stoma use, appearing to reduce the risk for PL.

Risk Factors for Outlet Obstruction in Patients with Diverting Ileostomy Following Rectal Surgery

Objectives:

Anastomotic leakage is one of the most severe complications of rectal cancer surgery. A diverting ileostomy was constructed for the purpose of reducing anastomotic failure risk. Outlet obstruction (OO) is one of the complications of diverting stoma that results in a lack of fecal discharge from the stoma. Detailed etiologies and preventive measures for outlet obstruction have not yet been identified.

Methods:

We studied 125 patients who underwent rectal resection, anastomosis, and elective ileostomy. We evaluated the incidence of outlet obstruction and looked for any relationship between perioperative factors and outlet obstruction.

Results:

Outlet obstruction was detected in 20 cases (16.0%). Outlet obstruction occurred 9 days after surgery in most cases. Inserting a decompressing tube improved obstructive symptoms in 4 days. Patients were divided into two cohorts according to the occurrence of outlet obstruction. Postoperative hospital stay was longer in the outlet obstruction group (19 vs. 15 days; p = 0.0003). A multivariate analysis identified that younger patients, a postoperative thicker rectus abdominis muscle at the stoma passage and high output syndrome were independent risk factors for outlet obstruction.

Conclusions:

Younger patients, a postoperative thicker rectus abdominis muscle at stoma passage and high output syndrome were independent risk factors for outlet obstruction.

Impact of anastomotic leakage on postoperative survival of patients with colorectal cancer: A meta-analysis using propensity score matching studies

OBJECTIVE

To explore the influence of anastomotic leakage (AL) on postoperative survival in patients with colorectal cancer (CRC).

BACKGROUND

Although several studies have compared the postoperative survival of patients with CRC with and without AL, the background characteristics of the two groups were not aligned in most studies.

METHODS

We performed a comprehensive electronic search of the literature up to March 2020 to identify propensity score matching (PSM) studies that compared postoperative survival between CRC patients with and without AL. A meta-analysis was performed using random-effects models to calculate the risk ratio (RR) and 95% confidence interval (CI), and heterogeneity was analyzed using I (Akiyoshi et al., 2011) [2] statistics.

RESULTS

Four PSM studies involving a total of 1676 patients with CRC undergoing surgery were included in this meta-analysis. Among 234 patients who had AL, 163 (69.7%) survived at 5 years after surgery, whereas among 1422 patients who did not have AL, 1156 (81.3%) survived at 5 years after surgery. Background characteristics of the two groups were adjusted with PSM in all 4 studies. The result of the meta-analysis revealed a significant difference between the two groups (RR, 1.63; 95% CI, 1.09-2.45; P = 0.02; I² = 66%) in 5-year overall survival (OS).

CONCLUSIONS

The results of this meta-analysis demonstrate a significantly decreased 5-year OS in patients with CRC who had AL compared with patients with CRC who did not have AL.

Reinforcement of Colonic Anastomosis with Improved Ultrafine Nanofibrous Patch: Experiment on Pig

Anastomotic leakage is a dreadful complication in colorectal surgery. It has a negative impact on postoperative mortality, long term life quality and oncological results. Nanofibrous polycaprolactone materials have shown pro-healing properties in various applications before. Our team developed several versions of these for healing support of colorectal anastomoses with promising results in previous years. In this study, we developed highly porous biocompatible polycaprolactone nanofibrous patches. We constructed a defective anastomosis on the large intestine of 16 pigs, covered the anastomoses with the patch in 8 animals (Experimental group) and left the rest uncovered (Control group). After 21 days of observation we evaluated postoperative changes, signs of leakage and other complications. The samples were assessed histologically according to standardized protocols. The material was easy to work with. All animals survived with no major complication. There were no differences in intestinal wall integrity between the groups and there were no signs of anastomotic leakage in any animal. The levels of collagen were significantly higher in the Experimental group, which we consider to be an indirect sign of higher mechanical strength. The material shall be further perfected in the future and possibly combined with active molecules to specifically influence the healing process.

Simultaneous approach for patients with synchronous colon and rectal liver metastases: Impact of site of primary on postoperative and oncological outcomes

BACKGROUND AND AIMS

We aimed to investigate the impact of the site of the primary on postoperative and oncological outcomes in patients undergone simultaneous approach for colon (CC) and rectal cancer (RC) with synchronous liver metastases (SCRLM).

PATIENTS AND METHODS

Of the 220 patients with SCRLM operated on between Mar 2006 and Dec 2017, 169 patients (76.8%) were treated by a simultaneous approach and were included in the study. Two groups were considered according to the location of primary tumor RC-Group (n = 47) and CC-group (n = 122).

RESULTS

Multiple liver metastases were observed in 70.2% in RC-Group and 77.0% in CC-Group (p = 0.233), whilst median Tumor Burden Score (TBS) was 4.7 in RC-Group and 5.4 CC-Group (p = 0.276). Severe morbidity (p = 0.315) and mortality at 90 days (p = 0.520) were comparable between RC-Group and CC-Group. The 5-year overall survival (OS) rate was similar comparing RC-Group and CC-Group (48.2% vs. 45.3%; p = 0.709), but it was significantly different when considering left-CC, right-CC and RC separately (54.5% vs. 35.2% vs. 48.2%; p = 0.041). Primary tumor location (right-CC, p = 0.001; RC, p = 0.002), microscopic residual (R1) disease at the primary (p < 0.001), TBS ≥6 (p = 0.012), bilobar metastases (p = 0.004), and chemotherapy strategy (preoperative ChT, p = 0.253; postoperative ChT, p = 0.012; and perioperative ChT, p < 0.001) resulted to be independent prognostic factors at multivariable analysis.

CONCLUSION

In patients with SCRLM, simultaneous resection of the primary tumor and liver metastases seems feasible and safe and allows satisfactory oncological outcomes both in CC and RC. Right-CC shows a worse prognosis when compared to left-CC and RC.

The influence of platelet-rich plasma (PRP) on colonic anastomosis healing impaired by intraperitoneal 5-flourouracil application. An experimental study

Purpose

5-flourourasil (5-FU) is commonly used for early intraperitoneal chemotherapy in colorectal or appendiceal cancer patients with peritoneal carcinomatosis. Due to its effect, anastomosis healing can be impaired and leads to anastomotic leakage. In this study, we aimed to investigate the potential healing effect of platelet-rich plasma (PRP) on colonic anastomosis impaired by intraperitoneal 5-flourouracil application.

Methods

After ten rats were sacrificed for preparing PRP, forty Wistar-albino rats were subjected to colonic anastomosis, and randomly allocated into four groups including 10 rats each. According to receiving PRP and/or 5-FU application, the groups were formed as control (C), 5-FU without PRP (CT), anastomosis with PRP (C-PRP), and 5-FU with PRP (CT-PRP). CT and CT-PRP groups also received 5-FU intraperitoneally on postoperative day 1 (POD 1). All animals were euthanized on pod 7. The body weight change, anastomotic bursting pressure (ABP), tissue hydroxiprolin (TH) and histopathological examination of each group were analyzed.

Results

5-FU application significantly reduced ABP levels when compared with group C, C-PRP and CT-PRP (for each comparison, p<0,01). PRP application in CT-PRP group raised the measure of ABP up to the levels of C group. Although tissue hydroxyproline levels (THL) levels of CT-PRP group were found higher than CT group, it was not significant (p=0.112). Microscopically, comparing with CT group, PRP application significantly promoted the healing of colonic anastomosis subjected to 5-FU application by improving tissue edema, necrosis, submucosal bridging and collagen formation (p<0.05). Tissue healing in CT-PRP group was observed as good as the control groups. (C, C-PRP, p=0.181, p=0.134; respectively).

Conclusion

PRP administration on colonic anastomosis significantly promotes the healing process of anastomosis in rats receiving 5-FU. This result encourages further clinical use of PRP to reduce the frequency of AL in patients receiving EPIC.