Impact of anastomotic leakage on long-term oncologic outcome and its related factors in rectal cancer

Clinical and computational development of a patient-calibrated ICGFA bowel transection recommender

INTRODUCTION

Intraoperative indocyanine green fluorescence angiography (ICGFA) aims to reduce colorectal anastomotic complications. However, signal interpretation is inconsistent and confounded by patient physiology and system behaviours. Here, we demonstrate a proof of concept of a novel clinical and computational method for patient calibrated quantitative ICGFA (QICGFA) bowel transection recommendation.

METHODS

Patients undergoing elective colorectal resection had colonic ICGFA both immediately after operative commencement prior to any dissection and again, as usual, just before anastomotic construction. Video recordings of both ICGFA acquisitions were blindly quantified post hoc across selected colonic regions of interest (ROIs) using tracking-quantification software and computationally compared with satisfactory perfusion assumed in second time-point ROIs, demonstrating 85% agreement with baseline ICGFA. ROI quantification outputs detailing projected perfusion sufficiency-insufficiency zones were compared to the actual surgeon-selected transection/anastomotic construction site for left/right-sided resections, respectively. Anastomotic outcomes were recorded, and tissue lactate was also measured in the devascularised colonic segment in a subgroup of patients. The novel perfusion zone projections were developed as full-screen recommendations via overlay heatmaps.

RESULTS

No patient suffered intra- or early postoperative anastomotic complications. Following computational development (n = 14) the software recommended zone (ROI) contained the expert surgical site of transection in almost all cases (Jaccard similarity index 0.91) of the nine patient validation series. Previously published ICGFA time-series milestone descriptors correlated moderately well, but lactate measurements did not. High resolution augmented reality heatmaps presenting recommendations from all pixels of the bowel ICGFA were generated for all cases.

CONCLUSIONS

By benchmarking to the patient's own baseline perfusion, this novel QICGFA method could allow the deployment of algorithmic personalised NIR bowel transection point recommendation in a way fitting existing clinical workflow.

Impact of standardising indocyanine green fluorescence angiography technique for visual and quantitative interpretation on interuser variability in colorectal surgery

AIM/BACKGROUND

Intra-operative colonic perfusion assessment via indocyanine green fluorescence angiography (ICGFA) aims to address malperfusion-related anastomotic complications; however, its interpretation suffers interuser variability (IUV), especially early in ICGFA experience. This work assesses the impact of a protocol developed for both operator-based judgement and computational development on interpretation consistency, focusing on senior surgeons yet to start using ICGFA.

METHODS

Experienced and junior gastrointestinal surgeons were invited to complete an ICGFA-experience questionnaire. They subsequently interpreted nine operative ICGFA videos regarding perfusion sufficiency of a surgically prepared distal colon during laparoscopic anterior resection by indicating their preferred site of proximal transection using an online annotation platform (mindstamp.com). Six ICGFA videos had been prepared with a clinical standardisation protocol controlling camera and patient positioning of which three each had monochrome near infrared (NIR) and overlay display. Three others were non-standardised controls with synchronous NIR and overlay picture-in-picture display. Differences in transection level between different cohorts were assessed for intraclass correlation coefficient (ICC) via ImageJ and IBM SPSS.

RESULTS

58 clinicians (12 ICGFA experts, 46 ICGFA inexperienced of whom 23 were either finished or within one year of finishing training and 23 were junior trainees) participated as per power calculations. 63% felt that ICGFA should be routinely deployed with 57% believing interpretative competence requires 11-50 cases. Transection level concordance was generally good (ICC = 0.869) across all videos and levels of expertise (0.833-0.915). However, poor agreement was evident with the standardised protocol videos for overlay presentation (0.208-0.345). Similarly, poor agreement was seen for the monochrome display (0.392-0.517), except for those who were trained but ICG inexperienced (0.877) although even here agreement was less than with unstandardised videos (0.943).

CONCLUSION

Colorectal ICGFA acquisition and display standardisation impacts IUV with this specific protocol tending to diminish surgeon interpretation consistency. ICGFA video recording for computational development may require dedicated protocols.

Impact of anastomotic leakage on long-term prognosis after colorectal cancer surgery

Colorectal cancer (CRC) is one of the most common malignancies in the world. Despite significant improvements in surgical technique, postoperative complications still occur in a fair percentage of patients undergoing colorectal surgery. The most feared complication is anastomotic leakage. It negatively affects short-term prognosis, with increased post-operative morbidity and mortality, higher hospitalization time and costs. Moreover, it may require further surgery with the creation of a permanent or temporary stoma. While there is no doubt about the negative impact of anastomotic dehiscence on the short-term prognosis of patients operated on for CRC, still under discussion is its impact on the long-term prognosis. Some authors have described an association between leakage and reduced overall survival, disease-free survival, and increased recurrence, while other Authors have found no real impact of dehiscence on long term prognosis. The purpose of this paper is to review all the literature about the impact of anastomotic dehiscence on long-term prognosis after CRC surgery. The main risk factors of leakage and early detection markers are also summarized.

Deconstructing mastery in colorectal fluorescence angiography interpretation

INTRODUCTION

Indocyanine green fluorescence angiography (ICGFA) is commonly used in colorectal anastomotic practice with limited pre-training. Recent work has shown that there is considerable inconsistency in signal interpretation between surgeons with minimal or no experience versus those consciously invested in mastery of the technique. Here, we deconstruct the fluorescence signal patterns of expert-annotated surgical ICGFA videos to understand better their correlation and combine this with structured interviews to ascertain whether such interpretative capability is conscious or unconscious.

METHODS

For fluorescence signal analysis, expert-annotated ICGFA videos (n = 24) were quantitatively interrogated using a boutique intensity tracker (IBM Research) to generate signal time plots. Such fluorescence intensity data were examined for inter-observer correlation (Intraclass Correlation Coefficients, ICC) at specific curve milestones: the maximum fluorescence signal (Fmax), the times to both achieve this maximum (Tmax), as well as half this maximum (T1/2max) and the ratio between these (T1/2/Tmax). Formal tele-interview with contributing experts (n = 6) was conducted with the narrative transcripts being thematically mapped, plotted, and qualitatively analyzed.

RESULTS

Correlation by mathematical measures was excellent (ICC0.9-1.0) for Fmax, Tmax, and T1/2max (0.95, 0.938, and 0.925, respectively) and moderate (0.5-0.75) for T1/2/Tmax (0.729). While all experts narrated a deliberate viewing strategy, their specific dynamic signal appreciation differed in the manner of description.

CONCLUSION

Expert ICGFA users demonstrate high correlation in mathematical measures of their signal interpretation although do so tacitly. Computational quantification of expert behavior can help develop the necessary lexicon and training sets as well as computer vision methodology to better exploit ICGFA technology.

Neoadjuvant chemoradiotherapy determines the prognostic impact of anastomotic leakage in advanced rectal cancer

Purpose

The prognostic impact of anastomotic leakage (AL) in rectal cancer remains uncertain. We investigated the prognostic significance of AL in rectal cancer patients who underwent curative surgery, especially in terms of chemoradiotherapy.

Methods

A total of 1,818 rectal cancer patients who underwent radical surgery from 2011 to 2015 were retrospectively evaluated. We categorized patients according to AL and compared survival outcomes between the groups before and after matching. In locally advanced rectal cancer patients, we classified patients according to neoadjuvant chemoradiotherapy (nCRT) or adjuvant chemotherapy (aCTx) and analyzed survival outcomes according to AL in each group.

Results

Before matching, overall survival (OS) was significantly worse in the AL (+) group compared to the AL (–) group (P = 0.004). In matched patients, there were no differences in disease-free survival (DFS) and OS between groups (P = 0.423 and P = 0.083, respectively). In subgroup analysis for locally advanced rectal cancer, patients were classified as follows: nCRT (+) and aCTx (+) group; nCRT (+) and aCTx (–) group; nCRT (–) and aCTx (+) group; and nCRT (–) and aCTx (–) group. In the nCRT (–) and aCTx (+) group, patients with AL exhibited significantly worse DFS than patients without AL (P = 0.040). In the other 3 groups, there were no differences in DFS according to AL.

Conclusion

In locally advanced rectal cancer, AL had an adverse effect on oncologic outcome in patients receiving aCTx without nCRT but not in patients receiving nCRT.

Prognostic value of increased postoperative carcinoembryonic antigen in patients with early intestinal anastomosis leakage who underwent right hemicolectomy surgery

<b> Introduction:</b> Anastomotic leak after colorectal surgery is a serious complication that causes significant postoperative morbidity and mortality. </br></br> <b>Aim:</b> This study aimed to investigate the predictive value of increased postoperative carcinoembryonic antigen (CEA) in early intestinal anastomosis leakage in patients who underwent right hemicolectomy surgery.</br></br> <b>Material and methods:</b> In this prospective study, 535 patients who underwent right colon cancer surgery with stapled anastomosis were enrolled. A subset of 315 patients was included in the study after meeting the inclusion criteria. Preoperatively, their serum CEA levels were measured, and on postoperative days 3 and 6, the levels were measured again.</br></br> <b>Results:</b> Early AL occurred in 18 patients (5.71%). The mean SD age of patients was 65.06 11.69 years. Increased CEA level was associated with increased odds of intestinal AL among the patients after three and six days of surgery (OR after three days = 1.3; 95%CI = 1.11.5, OR after six days = 1.7 95%CI = 1.142.5). The mean CEA level significantly increased among patients with anastomose leakage (P-value < 0.001). </br></br> <b>Conclusion:</b> The results showed that increasing CEA levels can be used as one of the non-invasive markers in detecting early AL in patients with right colon cancer surgery.

Transanal Total Mesorectal Excision for Malignant Rectal Lesion: A Prospective Cohort Study

AIMS: The main outcome of this study was to use the transanal total mesorectal excision (TaTME) technique for rectal cancer resection and to assess as a primary endpoint the short-term oncological outcome; in terms of circumferential resection margin, longitudinal resection margins (proximally and distally), and lymph nodes (LN) retrieval, while secondary endpoints were operative time, estimated blood loss, length of hospital stay, cost per case, and overall complication rate. METHODS: This was a prospective cohort study. Forty patients were included and subjected to TaTME from May 2018 to January 2020 and patients were followed up for a period of 6 months. RESULTS: Primary endpoint: Depending on the post-operative specimen pathological assessment; circumferential resection margin (CRM) was free in all patients, proximal resection margins had a mean 14.37 2.87 cm, distal resection margins had a mean 2.08 ± 0.4 cm and LNs retrieval had a mean 13.27 ± 5.9, and number of positive LNs had a mean 2.40 ± 3.77. Secondary endpoints: Mean total operative time (from induction of anesthesia till skin closure) was 179.10, estimated blood loss (using gauze visual analog plus what was obtained in the OR suction device) was 133.67 66.59 ml, the length of hospital stay (admission till discharge) was 5.27 ± 1.08 days, cost per case had a mean (in 1000 USD) 2.95 ± 0.12, and overall complication rate was 10%. CONCLUSION: TaTME represents a promising complementary technique to laparoscopic TME in the step of low rectal dissection.

The influence and countermeasure of obesity in laparoscopic colorectal resection

BACKGROUND

The aim of this study was to investigate the influence of obesity and the usefulness of a preoperative weight loss program (PWLP) for obese patients undergoing laparoscopic colorectal resection (LCR).

METHODS

Study 1: 392 patients who underwent LCR for colorectal cancer were divided into two groups: those with a body mass index (BMI) ≥25 kg/m2 (n = 113) and those with a BMI <25 kg/m2 (n = 279). The influence of BMI on LCR was investigated. Study 2: Patients with a BMI ≥28 kg/m2 who were scheduled to undergo LCR (n = 7, mean body weight 87.0 kg, mean BMI 33.9 kg/m2) undertook a PWLP including caloric restriction and exercise for 29.6 (15-70) days. The effects of this program were evaluated.

RESULTS

Study 1: The BMI ≥25 kg/m2 group had a prolongation of operation time and hospital stay than the BMI <25 kg/m2 group. Study 2: The patients achieved a mean weight loss of 6.9% (-6.0 kg). The mean visceral fat area was significantly decreased by 18.0%, whereas the skeletal muscle mass was unaffected. The PWLP group had a significantly lower prevalence of postoperative complications compared with the BMI ≥25 kg/m2 group.

CONCLUSION

Obesity affected the surgical outcomes in LCR. A PWLP may be useful for obese patients undergoing LCR.

Surgery for Colorectal Cancer: A Trigger for Liver Metastases Development? New Insights into the Underlying Mechanisms

Surgery is a crucial intervention and provides the best chance of cure for patients with colorectal cancer. Experimental and clinical evidence, however, suggests that paradoxically surgery itself may precipitate or accelerate tumor recurrence and/or liver metastasis development. This review addresses the various aspects of surgery-induced metastasis formation and sheds light on the role of inflammation as potential trigger for metastasis development. Understanding these mechanisms may provide potential new perioperative interventions to improve treatment outcomes, and as such could transform the perioperative timeframe from a facilitator of metastatic progression to a window of opportunity to reduce the risk of liver metastasis development. Ultimately, this can potentially improve long-term survival rates and quality of life in patients with colorectal cancer.

The impact of anastomotic leakage on oncology after curative anterior resection for rectal cancer: A systematic review and meta-analysis

BACKGROUND

Anastomotic leakage (AL) is a serious clinical complication after anterior resection for rectal cancer and will lead to an increase in postoperative mortality. However, the effect on long-term oncology outcomes remains controversial.

METHODS

We searched the PubMed, Embase, and Cochrane library databases for related articles. The included studies assessed local recurrence, distant recurrence, overall survival, cancer-specific survival and disease-free survival. The systematic reviews and meta-analyses was conducted in accordance with the PRISMA guidelines. The combined RRs with 95% CI were then calculated using a fixed effects model or a randomized effect model.

RESULTS

A total of 18 cohort studies included 34,487 patients who met the inclusion criteria. The meta-analysis demonstrated that AL was associated with increased local recurrence (RR 1.47, 95% CI 1.14-1.90, I = 57.8%). Anastomotic leakage decreased overall survival (RR 0.92, 95% CI 0.88-0.96, I = 58.1%), cancer-specific survival (RR 0.96, 95% CI 0.92-1.00, I = 30.4%), and disease-free survival (RR 0.85, 95% CI 0.77-0.94, I = 80.4%). Distant recurrence may had no significant effects of AL (RR 1.16, 95% CI 0.91-1.46, I = 58.4%).

CONCLUSION

AL has a negative effect on local recurrence and long-term survival (including overall survival, cancer-specific survival, and disease-free survival) after anterior resection for rectal cancer, but not related to distant recurrence.

A double-lumen irrigation-suction tube placed during operation could reduce the risk of grade C anastomotic leakage resulting from selective sigmoid colon cancer radical resection

AIM

This study investigated the effect of a double-lumen irrigation-suction tube in reducing the incidence of grade C anastomotic leakage (AL) resulting from a selective sigmoid colon cancer radical resection.

METHOD

This multicenter retrospective cohort study reviewed data of patients receiving sigmoid colon cancer radical resection from January 2010 to November 2019. The enrolled patients were divided into the passive drainage tube group and the double-lumen irrigation-suction tube group, based on the use of a double-lumen irrigation-suction tube or a passive drainage tube during the surgery. The effect of double-lumen irrigation-suction tube on the incidence of grade C anastomotic leakage was evaluated.

RESULTS

Of the 761 patients included in the study, 56 patients (7.36%) experienced AL. Of the 56 patients, 22 were diagnosed with grade C AL. The double-lumen irrigation-suction tube was a protective factor for forming a grade C AL compared with the passive drainage tube (OR = 0.194, 95% CI: 0.055-0.686, p = 0.011). Of the 34 patients with grade A or B AL, 26 patients had spontaneous closure-19 in the double-lumen irrigation-suction tube group and 7 in the passive drainage tube group. The double-lumen irrigation-suction tube (multivariable HR = 3.418, 95% CI: 1.43-11.203, p = 0.038) was associated with spontaneous closure of grade A or B AL.

CONCLUSION

Placing a double-lumen irrigation-suction tube may reduce the risk of grade C AL resulting from a selective sigmoid colon cancer radical resection. However, this study had substantial selection bias and the results should be reconfirmed by a randomized clinical trial.

Does anastomotic leakage after rectal cancer resection worsen long-term oncologic outcome?

PURPOSE

The influence of anastomotic leakage on long-term survival in patients with rectal cancer is debatable. The aim of this study was to evaluate relationships between anastomotic leakage and long-term survival.

METHODS

In this multicenter retrospective cohort study, 395 consecutive stage I to III rectal cancer patients underwent anterior resection between 2007 and 2012. Five-year overall survival, 5-year disease-free survival, and 5-year local recurrence-free survival were compared between patients with leakage (Leakage (+)) and patients without leakage (Leakage (-)).

RESULTS

Of 395 patients, 50 (12.7%) had anastomotic leakage. Of these 50, 34 (68.0%) required urgent surgery and 16 (32.0%) could be managed by watchful waiting or with percutaneous drainage. The median follow-up period was 62.6 months. Five-year overall survival did not differ between the two groups (Leakage (+) 93.8% vs. Leakage (-) 89.0%, P = 0.121). Five-year disease-free survival also did not differ between the two groups (81.6% vs. 80.3%, P = 0.731), and neither did 5-year local recurrence-free survival (91.9% vs. 86.1%, P = 0.206). In a multivariable Cox regression model, BMI > 25, preoperative CA19-9 > 37, pathological T stage, pathological N stage, and circumferential resection margin (CRM) positive were independent predictors of disease-free survival. Moreover, pathological T stage, pathological N stage, and CRM positive were the only independent predictors of overall survival and local recurrence-free survival. Anastomotic leakage was not a risk factor for overall survival, disease-free survival, or local recurrence-free survival.

CONCLUSION

Anastomotic leakage is not associated with a significant decrease in long-term survival in rectal cancer patients.

Meta-analysis of the impact of postoperative infective complications on oncological outcomes in colorectal cancer surgery

BACKGROUND

Cancer outcomes are complex, involving prevention, early detection and optimal multidisciplinary care. Postoperative infection and surgical site-infection (SSI) are not only uncomfortable for patients and costly, but may also be associated with poor oncological outcomes. A meta-analysis was undertaken to assess the oncological effects of SSI in patients with colorectal cancer.

METHODS

An ethically approved PROSPERO-registered meta-analysis was conducted following PRISMA guidelines. PubMed and Scopus databases were searched for studies published between 2007 and 2017 reporting the effects of postoperative infective complications on oncological survival in colorectal cancer. Results were separated into those for SSI and those concerning anastomotic leakage. Articles with a Methodological Index for Non-Randomized Studies score of at least 18 were included. Hazard ratios (HRs) with 95 per cent confidence intervals were computed for risk factors using an observed to expected and variance fixed-effect model.

RESULTS

Of 5027 articles were reviewed, 43 met the inclusion criteria, with a total of 154 981 patients. Infective complications had significant negative effects on overall survival (HR 1·37, 95 per cent c.i. 1·28 to 1·46) and cancer-specific survival (HR 2·58, 2·15 to 3·10). Anastomotic leakage occurred in 7·4 per cent and had a significant negative impact on disease-free survival (HR 1·14, 1·09 to 1·20), overall survival (HR 1·34, 1·28 to 1·39), cancer-specific survival (HR 1·43, 1·31 to 1·55), local recurrence (HR 1·18, 1·06 to 1·32) and overall recurrence (HR 1·46, 1·27 to 1·68).

CONCLUSION

This meta-analysis identified a significant negative impact of postoperative infective complications on overall and cancer-specific survival in patients undergoing colorectal surgery.

Long-term Oncological Outcomes Following Anastomotic Leak in Rectal Cancer Surgery

BACKGROUND

Anastomotic leak remains a critical complication after restorative rectal cancer surgery and is associated with significant morbidity and mortality rates, whereas reported rates range from 4% to 29%. Whether the occurrence of leak may have an impact on long-term oncological outcomes is under debate.

OBJECTIVE

This study aimed to describe the oncological impact of anastomotic leak on patients undergoing sphincter-preserving surgery for rectal adenocarcinoma.

DESIGN

This is a retrospective review of a prospectively maintained database.

SETTINGS

The study was conducted at a high-volume colorectal center.

PATIENTS

Data on patients who underwent restorative surgery for rectal adenocarcinoma from January 2000 until December 2013 were retrospectively analyzed.

MAIN OUTCOME MEASURES

The primary outcome measured was the impact of anastomotic leak, defined according to the classification proposed by the International Study Group of Rectal Cancer, on long-term overall survival, disease-free survival, disease-specific survival, and local recurrence.

RESULTS

A total of 787 patients undergoing sphincter-preserving surgery for rectal cancer met the inclusion criteria. Forty-two (5.3%) patients presented a symptomatic anastomotic leak. The median follow-up period was 64 months. Fifty-one (6.5%) patients experienced a cancer-related death, 2 of 42 in the anastomotic leak group. Five-year overall survival, disease-specific survival, and disease-free survival were 88%, 94.7%, and 85.3%. Local recurrence rate was 2%. There was no difference in long-term overall survival, disease-specific survival, disease-free survival, and local recurrence rate between groups. On a multivariable analysis, anastomotic leak did not impact oncological outcomes.

LIMITATIONS

This study was limited by retrospective analysis.

CONCLUSIONS

The occurrence of anastomotic leak after restorative resection for rectal cancer did not impact long-term oncological outcomes in our cohort of patients. See Video Abstract at http://links.lww.com/DCR/B187. RESULTADOS ONCOLÓGICOS A LARGO PLAZO DESPUÉS DE UNA FUGA ANASTOMÓTICA EN CIRUGÍA DE CÁNCER RECTAL: La fuga anastomótica sigue siendo una complicación crítica después de la cirugía restauradora del cáncer rectal y se asocia con tasas significativas de morbilidad y mortalidad, mientras que las tasas reportadas varían del 4% al 29%. Se está debatiendo si la aparición de fugas puede tener un impacto en los resultados oncológicos a largo plazo.Describir el impacto oncológico de la fuga anastomótica en pacientes sometidos a cirugía de preservación del esfínter para adenocarcinoma rectal.Revisión retrospectiva de una base de datos mantenida prospectivamente.El estudio se realizó en un centro colorrectal de alto volumen.Se analizaron retrospectivamente los datos de pacientes que se sometieron a cirugía reparadora por adenocarcinoma rectal desde Enero de 2000 hasta Diciembre de 2013.Impacto de la fuga anastomótica, definida de acuerdo con la clasificación propuesta por el Grupo de Estudio Internacional del Cáncer Rectal (International Study Group of Rectal Cancer), sobre la supervivencia general a largo plazo, la supervivencia libre de enfermedad, la supervivencia específica de la enfermedad y la recurrencia local.Un total de 787 pacientes sometidos a cirugía para preservar el esfínter por cáncer rectal cumplieron con los criterios de inclusión. Cuarenta y dos (5.3%) pacientes presentaron una fuga anastomótica sintomática. El tiempo mediano del período de seguimiento fue de 64 meses. Cincuenta y un (6.5%) pacientes sufrieron muerte relacionada con el cáncer, 2 de 42 en el grupo de fuga anastomótica. La supervivencia global a cinco años, la supervivencia específica de la enfermedad y la supervivencia libre de enfermedad fueron del 88%, 94.7% y 85.3%, respectivamente. La tasa de recurrencia local fue del 2%. No hubo diferencias en la supervivencia global a largo plazo, la supervivencia específica de la enfermedad, la supervivencia libre de enfermedad y la tasa de recurrencia local entre los grupos. En un análisis multivariable, la fuga anastomótica no afectó los resultados oncológicos.Este estudio fue limitado por análisis retrospectivo.La aparición de fuga anastomótica después de la resección restauradora para el cáncer rectal no afectó los resultados oncológicos a largo plazo en nuestra cohorte de pacientes. Consulte Video Resumen en http://links.lww.com/DCR/B187. (Traducción-Dr. Yesenia Rojas-Kahlil).

A Retrospective Study of Risk Factors for Symptomatic Anastomotic Leakage after Laparoscopic Anterior Resection of the Rectal Cancer without a Diverting Stoma

Background

Anastomotic leakage (AL) is a common and devastating postoperative issue for patients who have undergone anterior resection of rectal carcinoma and can lead to increased short-term morbidity and mortality. Moreover, it might be associated with a worse oncological prognosis of tumors. This study is aimed at exploring the risk factors for symptomatic AL after laparoscopic anterior resection (LAR) for rectal tumors without a preventive diverting stoma.

Materials and Methods

This case control study retrospectively reviewed the data of 496 consecutive patients who underwent LAR of the rectum without a preventive diverting stoma at the Cancer Hospital, Chinese Academy of Medical Sciences between September 2016 and September 2017. All patients were divided into an AL group and a control group based on the occurrence of postoperative symptomatic AL. Factors regarding patient-related variables, operation-related variables, and tumor-related variables were collected and assessed between the two groups through univariate and multivariate logistic regression analyses to identify independent risk factors for AL.

Results

In total, 18 (3.6%) patients developed postoperative symptomatic AL. Univariate analysis showed that a synchronous primary malignancy of the left hemicolon (P = 0.047), intraoperative chemotherapy (P = 0.003), and level of anastomosis (P = 0.033) were significantly related with AL. Multivariate analysis was subsequently performed to adjust for confounding biases and confirmed that a synchronous primary malignancy of the left hemicolon (odds ratio (OR), 12.225; 95% confidence interval (CI), 1.764-84.702; P = 0.011), intraoperative chemotherapy (OR, 3.931; 95% CI, 1.334-11.583; P = 0.013), and level of anastomosis (OR, 3.224; 95% CI, 1.124-9.249; P = 0.030) were independent risk factors for symptomatic AL for patients who received LAR for rectal neoplasms without a preventive diverting stoma.

Conclusions

Synchronous primary malignancy of the left hemicolon, intraoperative chemotherapy, and a low anastomotic level can increase the risks of postoperative symptomatic AL after LAR of the rectum without a protective diverting stoma.

The influence of anastomotic leakage for rectal cancer oncologic outcome: A systematic review and meta-analysis

BACKGROUND AND OBJECTIVE

Anastomotic leakage is a serious complication after arterial resection of rectal cancer. It has been found that anastomotic leakage is related to the oncological outcome. The purpose of the study is to evaluate the long-term outcome of the rectal tumor after anastomotic leakage.

METHODS

The effect of anastomotic leakage on the oncological outcome of rectal cancer was studied by electronic literature retrieval. Using the DerSimonian Laird random effect model to calculate the odds ratio and 95% confidence interval. Research heterogeneity was evaluated by Q statistics and I² , and bias was evaluated by funnel plot and Begg's test.

RESULTS

A total of 35 studies and 44 698 patients were included in the study. The studies have shown that anastomotic leakage is associated with local recurrence (OR = 1.93; 95% CI, 1.57-2.38; P < .0001), overall survival (OR = 1.64; 95% CI, 1.37-1.95; P < .00001), disease-free survival (OR = 2.07; 95% CI, 1.50-2.87; P < .00001) and cancer-specific survival (OR = 1.32; 95% CI, 1.02-1.70; P = .012), while it was not related to distant recurrence (OR = 1.25; 95% CI, 0.95-1.65; P = .12).

CONCLUSIONS

The results showed that anastomotic leakage after anterior resection increased the risk of local recurrence, decreased the overall survival, cancer-specific survival and disease-free survival.

Diverting Stoma Versus No Diversion in Laparoscopic Low Anterior Resection: A Single-center Retrospective Study in Japan

BACKGROUND/AIM

The purpose of this retrospective study was to describe the benefits and risks of a diverting stoma (DS) in laparoscopic low anterior resection (LAR) for rectal cancer.

MATERIALS AND METHODS

A total of 140 and 167 patients without and with DS, respectively, were included in this study in a high-volume cancer center of Japan within an 8-year period.

RESULTS

Small bowel obstruction occurred more frequently in patients with DS (2.86% vs. 16.17%, p<0.001). The difference in anastomotic leakage rate was not statistically significant (11.43% vs. 10.18%, p=0.72). In multivariate analysis, the operating time was associated with a higher rate of leakage in LAR [odds ratio (OR) 8.772, 95% confidence interval (CI)=1.002-1.012, p=0.027].

CONCLUSION

Operating time was associated with a higher rate of leakage in LAR for low rectal cancer. A DS did not reduce anastomotic leakage but increased the risk of postoperative intestinal obstruction in laparoscopic LAR.

Anastomotic leak in colorectal cancer patients: New insights and perspectives

Anastomotic leak (AL) remains a potentially life-threatening sequela of colorectal surgery impacting on mortality, short- and long-term morbidity, quality of life, local recurrence (LR) and disease-free survival. Despite technical improvements and the identification of several surgery- and patient-related factors associated to the risk of AL, its incidence has not significantly changed over time. In this context, the clarification of the mechanisms underlying anastomotic healing remains an important unmet need, crucial for improving patients' outcomes. This review concentrates on novel key findings in the etiopathogenesis of AL, how they can contribute in determining LR, and measures which may contribute to reducing its incidence. AL results from a complex, dynamic interplay of several factors and biological processes, including host genetics, gut microbiome, inflammation and the immune system. Many of these factors seem to act in concert to drive both AL and LR, even if the exact mechanisms remain to be elucidated. The next generation sequencing technology, including the microbial metagenomics, could lead to tailored bowel preparations targeting only those pathogens that can cause AL. Significant progress is being made in each of the reviewed areas, moving toward translational and targeted therapeutic strategies to prevent the difficult complication of AL.

Intraoperative intraperitoneal chemotherapy increases the incidence of anastomotic leakage after anterior resection of rectal tumors

BACKGROUND

Intraoperative intraperitoneal chemotherapy is an emerging treatment modality for locally advanced rectal neoplasms. However, its impacts on postoperative complications remain unknown. Anastomotic leakage (AL) is one of the most common and serious complications associated with the anterior resection of rectal tumors. Therefore, we designed this study to determine the effects of intraoperative intraperitoneal chemotherapy on AL.

AIM

To investigate whether intraoperative intraperitoneal chemotherapy increases the incidence of AL after the anterior resection of rectal neoplasms.

METHODS

This retrospective cohort study collected information from 477 consecutive patients who underwent an anterior resection of rectal carcinoma using the double stapling technique at our institution from September 2016 to September 2017. Based on the administration of intraoperative intraperitoneal chemotherapy or not, the patients were divided into a chemotherapy group (171 cases with intraperitoneal implantation of chemotherapy agents during the operation) or a control group (306 cases without intraoperative intraperitoneal chemotherapy). Clinicopathologic features, intraoperative treatment, and postoperative complications were recorded and analyzed to determine the effects of intraoperative intraperitoneal chemotherapy on the incidence of AL. The clinical outcomes of the two groups were also compared through survival analysis.

RESULTS

The univariate analysis showed a significantly higher incidence of AL in the patients who received intraoperative intraperitoneal chemotherapy, with 13 (7.6%) cases in the chemotherapy group and 5 (1.6%) cases in the control group (P = 0.001). As for the severity of AL, the AL patients who underwent intraoperative intraperitoneal chemotherapy tended to be more severe cases, and 12 (92.3%) out of 13 AL patients in the chemotherapy group and 2 (40.0%) out of 5 AL patients in the control group required a secondary operation (P = 0.044). A multivariate analysis was subsequently performed to adjust for the confounding factors and also showed that intraoperative intraperitoneal chemotherapy increased the incidence of AL (odds ratio = 5.386; 95%CI: 1.808-16.042; P = 0.002). However, the survival analysis demonstrated that intraoperative intraperitoneal chemotherapy could also improve the disease-free survival rates for patients with locally advanced rectal cancer.

CONCLUSION

Intraoperative intraperitoneal chemotherapy can improve the prognosis of patients with locally advanced rectal carcinoma, but it also increases the risk of AL following the anterior resection of rectal neoplasms.

Association of the prognostic nutritional index and overall survival in patients with colorectal cancer: A STROBE compliant retrospective cohort study

BACKGROUND

The TNM classification does not completely reflect the prognosis of patients with colorectal cancer (CRC). Several clinical factors have been used to increase its prognostic value, but factors pertaining to the patient's immunonutritional status have not usually been addressed. The aim of this study is to evaluate the role of Prognostic nutritional index (PNI) and other well-known prognostic factors by multivariate analysis in a cohort of patients with CRC.

METHODS

This is a retrospective cohort study of consecutive patients with CRC managed in a cancer center between January 1992 and December 2016. Cox's model was used to define the association of the PNI and other factors with Overall survival (OS).

RESULTS

A total of 3301 patients were included: 47.7% were female and 52.3% were male, with a mean age of 58.7 years. By bivariate analysis, PNI was strongly associated with OS (Risk ratio [RR] 0.968, 95% Confidence interval [CI] 0.962-0.974; P < 0.001). On multivariate analysis, PNI was an independent explanatory variable (as continuous variable and as categorized variable; RR 0.732, 95% CI 0.611-0.878; RR 0.656, 95% CI 0.529-0.813 and RR 0.646, 95% CI 0.521-0.802, for quintiles 2, 3, and 4-5, respectively); a biological gradient effect was demonstrated. The final prognostic model included PNI, location of the neoplasia in the colorectum, basal hemoglobin, lymphocyte count, neutrophil/lymphocyte ratio, platelet/lymphocyte ratio, TNM stage, differentiation degree, R classification, and postoperative complications.

CONCLUSIONS

PNI is a significant and independent prognostic factor in patients with CRC. Its prognostic value adds precision to the TNM staging system including specific subgroups of patients with CRC; it should be evaluated in prospective clinical studies.

Transanal total mesorectal excision (TaTME): current status and future perspectives

Total mesorectal excision (TME) is the gold standard surgical treatment for mid- and low rectal cancer; however, it is associated with specific technical hurdles. Transanal TME (TaTME) is a new procedure developed to overcome these difficulties, through an enhanced visualization of the dissection plane. This potentially could result in a more accurate distal dissection with a lower rate of positive circumferential resection margins, increasing the rate of sphincter-saving procedures. The indications for TaTME are currently expanding, despite not being yet standardized, and structured training programs are ongoing to help overcome the steep learning curve related to the technique. The procedure is feasible and safe with similar intraoperative complications and readmission rates when compared with conventional open or laparoscopic TME. Favorable short-term oncologic results have been reported: in particular, TaTME is associated with mesorectal specimen of a better quality and a longer distal resection margin that is established at the beginning of the procedure under direct view. Robotics, when available, will probably overcome the steep learning curve related to the complexity of TaTME. Long-term follow-up and ongoing RCT trials data are awaited regarding functional results, local recurrence and survival, and to facilitate the comparison with standard laparoscopic or robotic rectal resections. The present review is focused on critically analyzing the theoretical benefits and risks of the procedure, its indications, short- and long-term results and future direction in the application of TaTME.

Early reoperation following pancreaticoduodenectomy: impact on morbidity, mortality, and long-term survival

Background

Reoperation following PD is a surrogate marker for a complex post-operative course and may lead to devastating consequences. We evaluate the indications for early reoperation following PD and analyze its effect on short- and long-term outcome.

Methods

Four hundred and thirty-three patients that underwent PD between August 2006 and June 2016 were retrospectively analyzed.

Results

Forty-eight patients (11%; ROp group) underwent 60 reoperations within 60 days from PD. Forty-two patients underwent 1 reoperation, and 6 had up to 6 reoperations. The average time to first reoperation was 10.1 ± 13.4 days. The most common indications were anastomotic leaks (22 operations in 18 patients; 37.5% of ROp), followed by post-pancreatectomy hemorrhage (PPH) (14 reoperations in 12 patients; 25%), and wound complications in 10 (20.8%). Patients with cholangiocarcinoma had the highest reoperation rate (25%) followed by ductal adenocarcinoma (12.3%). Reoperation was associated with increased length of hospital stay and a high post-operative mortality of 18.7%, compared to 2.6% for the non-reoperated group. For those who survived the post-operative period, the overall and disease-free survival were not affected by reoperation.

Conclusions

Early reoperations following PD carries a dramatically increased mortality rate, but has no impact on long-term survival.

Oncologic outcome and recurrence rate following anastomotic leakage after curative resection for colorectal cancer

INTRODUCTION

Anastomotic leakage is one of the most severe early complications after colorectal surgery, and it is associated with a high reoperation rate-, and increased in short-term morbidity and mortality rates. It remains unclear whether anastomotic leakage is associated with poor oncologic outcomes. The aim of this study was to determine the impacts of anastomotic leakage on long-term oncologic outcomes, disease-free survival and overall mortality in patients who underwent curative surgery for colorectal cancer.

METHODS

This single-centre, retrospective, observational cohort study included patients who underwent curative surgery for colorectal cancer between 2005 and 2015 and who had a primary anastomosis. Survival- and multivariate cox regression analyses were performed to adjust for confounding.

RESULTS

A total of 1984 patients had a primary anastomosis after surgery. The overall incidence of anastomotic leakage was 7.5%; 19 patients were excluded because they were lost to follow-up. Of the remaining 1965 patients, 41 (2.1%) developed local recurrence associated with anastomotic leakage [adjusted hazard ratio (HR) = 2.25; 95% confidence interval (CI) 1.14-5.29; P = 0.03]. Distant recurrence developed in 291(14.8%) patients with no association with anastomotic leakage [adjusted HR = 1.30 (95% CI: 0.85-1.97) P = 0.23]. Anastomotic leakage was associated with increased long-term mortality [adjusted HR = 1.69 (95% CI 1.32-2.18) P < 0.01]. Five year disease-free survival was significantly decreased in patients with anastomotic leakage, (log rank test P < 0.01).

CONCLUSION

Anastomotic leakage was significantly associated with increased rates of local recurrence, disease free-survival and overall mortality. Associations of anastomotic leakage with distant recurrence was not found.

[Influence of anastomotic leakage on the long-term outcomes in patients with colorectal cancer]

Anastomotic leakage after surgery for colorectal cancer is a widely known factor aggravating immediate outcomes. At the same time, deterioration of oncological results is under much less attention. Long-term consequences of anastomotic leakage and possible mechanism of negative effect of this complication on long-term results are reviewed in the article.