Anterior Resection for Rectal Cancer and Visceral Blood Flow: An Explorative Study

High ligation versus low ligation of the inferior mesenteric artery in laparoscopic rectal cancer surgery: a retrospective study on surgical and long-term outcome

BACKGROUND

In laparoscopic low anterior resection for rectal cancer surgery, there has been controversy to whether the inferior mesenteric artery (IMA) should be ligated at the origin of its aorta (high ligation (HL)) or below the branches of the left colonic artery (LCA) (low ligation (LL)). This study was intended to clarify oncological outcome and long-term prognosis of retrospective analysis.

METHODS

Analyzed the cases who underwent laparoscopic low anterior resection (LAR) in Shanghai Ruijin Hospital from January 2015 to December 2016, 357patients scheduled into 2 groups according to the level of IMA ligation: HL (n = 247) versus LL (n = 110).

RESULTS

The primary endpoint is long-term outcomes, and the secondary endpoint is the incidence rate of major postoperative complications. There were no significant differences in 5-year overall survival (P = 0.92) and 5-year disease-free survival (P = 0.41). There were no differences between the clinical baseline levels in each group. The incidence of low anterior resection syndrome (LARS) in the two groups was statistically significant (P = 0.037). No significant differences were observed in operative time (P = 0.092) and intraoperative blood loss (P = 0.118). In the HL group, 6 cases (2.4%) had additional colonic excision due to poor anastomotic blood supply; none of the colonic anastomosis in the low ligation group had ischemic manifestations, and length from the proximal margin (P = 0.076), length from the distal margin (P = 0.184), the total number of lymph nodes excised (P = 0.065), and anastomotic leakage incidence (P = 0.33).

CONCLUSION

Low ligation of the IMA which reserved LCA with vascular root lymph node dissection in laparoscopic low anterior resection for rectal cancer surgery may help protect the blood supply of the anastomosis, and will not increase postoperative complications while enhance recovery, without compromising radical excision and long-term prognosis.

Real-time semi-quantitative assessment of anastomotic blood perfusion in mini‑invasive rectal resections by Sidestream Dark Field (SDF) imaging technology: a prospective in vivo pilot study

PURPOSE

Anastomotic leakage (AL) is one of the severe complications after rectal surgery, and anastomotic ischemia is one of the main factors. This prospective in vivo pilot study aimed to evaluate the effectiveness of Sidestream Dark Field (SDF) imaging in quantitative assessment of anastomotic microcirculation and to analyze its correlation with AL.

METHODS

Thirty-three patients with rectal cancer who underwent laparoscopic low anterior resection from 2019 to 2020 were enrolled. Microcirculation was measured by SDF imaging at the descending colon, the mesocolon transection line (MTL), and 1 cm and 2 cm distal to the MTL. Anastomotic microcirculation was measured at the stapler anvil edge before anastomosis. Quantitative perfusion-related parameters were as follows: microcirculation flow index (MFI), perfused vessel density (PVD), proportion of perfused vessels (PPV), and total vessel density (TVD).

RESULTS

All patients obtained stable microcirculation images. Functional microcirculation parameters (MFI, PPV, PVD) decreased successively from the descending colon, the colon at MTL, and 1 cm and 2 cm distal to the MTL (all P < 0.01). Extremely poor microcirculation was found at the intestinal segment 2 cm distal to the MTL. Micro-perfusion was significantly lower at the colonic limb of the anastomosis compared with the descending colon (all P < 0.001). Anastomotic leakage occurred in 3 patients (9.1%) whose anastomotic microcirculation was significantly lower than those without AL (all P < 0.01). Blood perfusion at the colonic limb of the anastomosis was significantly higher in patients with left colic artery preservation than in controls.

CONCLUSION

SDF imaging is a promising technique for evaluating anastomotic microcirculation and has potential clinical significance for risk stratification of AL.

Predictive Factors for Anastomotic Leakage Following Colorectal Cancer Surgery: Where Are We and Where Are We Going?

Anastomotic leakage (AL) remains one of the most severe complications following colorectal cancer (CRC) surgery. Indeed, leaks that may occur after any type of intestinal anastomosis are commonly associated with a higher reoperation rate and an increased risk of postoperative morbidity and mortality. At first, our review aims to identify specific preoperative, intraoperative and perioperative factors that eventually lead to the development of anastomotic dehiscence based on the current literature. We will also investigate the role of several biomarkers in predicting the presence of ALs following colorectal surgery. Despite significant improvements in perioperative care, advances in surgical techniques, and a high index of suspicion of this complication, the incidence of AL remained stable during the last decades. Thus, gaining a better knowledge of the risk factors that influence the AL rates may help identify high-risk surgical patients requiring more intensive perioperative surveillance. Furthermore, prompt diagnosis of this severe complication may help improve patient survival. To date, several studies have identified predictive biomarkers of ALs, which are most commonly associated with the inflammatory response to colorectal surgery. Interestingly, early diagnosis and evaluation of the severity of this complication may offer a significant opportunity to guide clinical judgement and decision-making.

Melatonin modulates rectal and body surface temperatures and their circadian rhythmicity in donkeys (Equus asinus) subjected to packing during the hot-dry season

The study aimed to evaluate the effects of melatonin administration on rectal and body surface temperature (RT and BST, respectively) responses and their circadian rhythmicity in donkeys subjected to packing (load carrying) during the hot-dry season. Twenty donkeys were divided into two equal groups randomly: Groups 1 (packing + melatonin) and 2 (packing - melatonin), subjected to packing and both covered 20 km. The RT, BST, and thermal environmental parameters were measured before and after packing. The procedure was carried out three times within the week, one day apart. This was followed 16-h after the last (third) packing procedure by 27-h recording period of all the parameters at 3-h intervals. The RT (37.77 ± 0.1℃) recorded in packing + melatonin donkeys was lower (P < 0.05) than in (packing - melatonin) (38.29 ± 0.1℃) post-packing, while the BSTs in packing + melatonin donkeys were lower than in (packing - melatonin) donkeys, especially the neck (33.07 ± 0.6℃ vs 35.4 ± 0.7℃, respectively) and coronary band (30.58 ± 0.5℃ vs 33.38 ± 0.7℃, respectively) temperatures. In both groups 16-h post-packing, overall mean RT and BST values were not different, except the coronary band temperature (26.61 ± 0.8℃) that was lower (P < 0.05) in packing + melatonin donkeys than (packing - melatonin) donkeys (28.78 ± 1.4℃). Melatonin-exerted biphasic effects on circadian rhythms of RT and BSTs by reducing body temperatures during the photophase and increasing the values during the scotophase in pack donkeys. In conclusion, melatonin may enhance packing output in donkeys during the hot-dry season.

Impacts of trans‐anal tube placement in patients with sigmoid colon cancer: Risk verification analysis using inverse probability weighting analysis

Purpose

Anastomotic leakage (AL) is a serious postoperative complication that affects short- and long-term outcomes. The use of a trans-anal drainage tube (TDT) is reported to prevent AL in rectal cancer patients, but its value in sigmoid colon cancer patients is unknown.

Methods

Admitted to the study were 379 patients who underwent surgery for sigmoid colon cancer between 2016 and 2020. Patients were divided into two groups according to the placement (n = 197) or nonplacement of a TDT (n = 182). To determine the factors affecting the association between TDT placement and AL, we estimated average treatment effects by stratifying each factor using the inverse probability of treatment weighting method. The association between prognosis and AL was evaluated in each identified factor.

Results

Factors associated with postsurgical insertion of a TDT were advanced age, male sex, high body mass index (BMI), poor performance status, and presence of comorbidities. TDT placement was associated with a significantly lower AL in male patients (odds ratio [OR], 0.22; 95% confidence interval [CI], 0.07-0.73; P = .013) and for BMI ≥ 25 kg/m² (OR, 0.13; 95% CI, 0.02-0.65; P = .013). In addition, there was a significant association of AL with poor prognosis in patients with BMI ≥ 25 kg/m² (P = .043), age > 75 y (P = .021), and pathological node-positive disease (P = .015).

Conclusion

Sigmoid colon cancer patients with BMI ≥ 25 kg/m² are the most appropriate candidates for postoperative TDT insertion, in terms of reduced incidence of AL and improved prognosis.

Left colic artery diameter is an important factor affecting anastomotic blood supply in sigmoid colon cancer or rectal cancer surgery: a pilot study

BACKGROUND

Anastomotic blood supply is vital to anastomotic healing. The aim of this study was to demonstrate the effect of the left colic artery (LCA) on blood supply in the anastomotic area, explore the relationship between individual differences in the LCA and blood supply in the anastomotic area, and elucidate the relevant indications for LCA retention during radical resection for sigmoid or rectal cancer.

METHOD

Radical sigmoid or rectal cancer resection with LCA retention was performed in 40 patients with colorectal cancer who participated in this study. Systemic pressure, LCA diameter, and the distance from the root of the LCA to the root of the inferior mesenteric artery were measured and recorded. The marginal artery stump pressure in the anastomotic colon before and after the LCA clamping was measured, respectively.

RESULTS

There is a significant difference between the marginal artery stump pressure before LCA ligation and after ligation (53.1 ± 12.38 vs 42.76 ± 12.71, p < 0.001). The anastomotic blood supply positively and linearly correlated with body mass index and systemic pressure. Receiver-operating curve analysis revealed that LCA diameter (area under the curve 0.971, cutoff 1.95 mm) was an effective predictor of LCA improving anastomosis blood supply. No relationship was found between the LCA root location and anastomotic blood supply.

CONCLUSION

Preserving the LCA is effective in improving blood supply in the anastomotic area, and larger LCA diameters result in a better blood supply to the anastomotic area.

Preservation versus nonpreservation of the left colic artery in anterior resection for rectal cancer: a propensity score-matched analysis

BACKGROUND

Preserving the left colic artery (LCA) during anterior resection for rectal cancer is controversial, and robust evidence of the outcomes of LCA preservation plus apical lymph node dissection is lacking. The purpose of this study was to investigate the impact of LCA preservation plus apical lymph node dissection surgery on anastomotic leakage and number of harvested lymph nodes.

METHODS

Patients who underwent laparoscopic or robotic anterior resection for rectal cancer between September 2017 and May 2020 were retrospectively assessed. The patients were categorized into two groups: preservation of LCA and nonpreservation of LCA. A one-to-one propensity score-matched analysis was performed to decrease confounding. The primary outcome was anastomotic leakage within 30 days after surgery. The secondary outcomes were number of harvested lymph nodes, 3-year overall survival, and 3-year disease-free survival.

RESULTS

A total of 216 patients were eligible for this study, and propensity score matching yielded 60 patients in each group. Anastomotic leakage in the LCA preservation group was significantly lower than that in the LCA nonpreservation group (3.3% vs. 13.3%, P = 0.048). No significant differences were observed in blood loss, operation time, intraoperative complications, splenic flexure mobilization, total number of harvested lymph nodes, number of positive lymph nodes, time to first flatus, or postoperative hospital stay. Kaplan-Meier survival analysis showed a 3-year disease-free survival of 85.7% vs. 80.5% (P = 0.738) and overall survival of 92.4% vs. 93.7% (P = 0.323) for the preservation and nonpreservation groups, respectively.

CONCLUSION

LCA preservation plus apical lymph node dissection surgery for rectal cancer may help reduce the incidence of anastomotic leakage without impairing the number of harvested lymph nodes. Preliminary results suggest that 3-year disease-free survival and overall survival rates may not differ between the two types of surgery, but studies with larger sample sizes are needed to confirm these conclusions. Trial registration ClinicalTrials.gov, NCT03776370. Registered 14 December 2018-Retrospectively registered, https://clinicaltrials.gov .

Preservation of the inferior mesenteric artery in laparoscopic nerve-sparing colorectal surgery for endometriosis

Laparoscopic rectosigmoid resection for endometriosis is usually performed with the section of the inferior mesenteric artery (IMA) distal to the left colic artery (low-tie ligation). This study was to determine outcomes in IMA-sparing surgery in endometriosis cases. A single-center retrospective study based on the analysis of clinical notes of women who underwent laparoscopic rectosigmoid segmental resection and IMA-sparing surgery for deep infiltrating endometriosis with bowel involvement between March the 1st, 2018 and February the 29th, 2020 in a referral hospital. During the study period, 1497 patients had major gynecological surgery in our referral center, of whom 253 (17%) for endometriosis. Of the 100 patients (39%) who had bowel endometriosis, 56 underwent laparoscopic nerve-sparing rectosigmoid segmental resection and IMA-sparing surgery was performed in 53 cases (95%). Short-term complications occurred in 4 cases (7%) without any case of anastomotic leak. Preservation of the IMA in colorectal surgery for endometriosis is feasible, safe and enables a tension-free anastomosis without an increase of postoperative complication rates.

Outcomes of level of ligation of inferior mesenteric artery in colorectal cancer: a systematic review and meta-analysis

The level of ligation of the inferior mesenteric artery (IMA) is a critical factor that can influence outcomes. The aim of this meta-analysis was to compare outcomes following high or low ligation of IMA. A systematic search was performed for relevant articles published between 2000 and 2020. Meta-analysis was performed using fixed-effects or random-effects models; 31 studies were included. Results show significantly lower rates of anastomotic leak, postoperative morbidity and urinary dysfunction with low ligation compared with high ligation. Though recurrence rates were similar, 5-year overall survival was longer in the low ligation group. Low ligation of IMA decreases anastomotic leak rates and overall morbidity. Addition of IMA nodal clearance to low ligation appears to improve overall survival in colorectal cancer.

Oncology Outcomes of Total Mesorectal Excision with Preservation of Both the Superior Rectum Artery and Left Colonic Artery for Upper-Rectal and Sigmoid Colon Cancers: A Meta-Analysis

Background: Total mesorectal resection (TME) has become the standard surgical procedure for resection of colorectal cancer tumors. We presented a systematic meta-analysis to evaluate the surgical outcomes of laparoscopic TME surgery with preservation or nonpreservation of both the superior rectum artery (SRA) and left colonic artery (LCA) for upper-rectal and sigmoid colon cancers. Methods: The comparative studies were systematically searched on PubMed, Science Direct, Web of Science, Wanfang Data, and China National Knowledge Infrastructure (CNKI) up to April 2021. Primary outcomes were oncology outcomes. And secondary outcomes involved surgical outcomes of interest and postoperative recovery. Results: Five relevant studies with a total of 761 patients undergoing laparoscopic TME surgery were eligible for meta-analysis. Three hundred seven patients received TME with preservation of both SRA and LCA (Group A), and 454 received TME surgery alone (Group B), respectively. Our results indicated that Group A had a less total postoperative complications (P = .000), lower anastomotic leakage rate (P = .002), shorter length of stay (P = .008), and longer operative time (P = .002). However, there was no significant difference between the two groups in terms of lymph node dissections (P = .188), intraoperative bleeding (P = .474), the first postoperative defecation (P = .943), recurrence rate (P = .547), and conversive rate (P = .504). Conclusions: Based on our meta-analysis, laparoscopic TME surgery with preservation of both the SRA and LCA for upper-rectal and sigmoid colon cancers may significantly receive better clinical and surgical outcomes. More well-designed large sample studies are required to replicate the short-term benefits and long-term oncologic outcomes.

Mucosal blood flow in the remaining rectal stump is more affected by total than partial mesorectal excision in patients undergoing anterior resection: a key to understanding differing rates of anastomotic leakage?

Purpose

Anterior resection is the procedure of choice for tumours in the mid and upper rectum. Depending on tumour height, a total mesorectal excision (TME) or partial mesorectal excision (PME) can be performed. Low anastomoses in particular have a high risk of developing anastomotic leakage, which might be explained by blood perfusion compromise. A pilot study indicated a worse blood flow in TME patients in an open setting. The aim of this study was to further evaluate perianastomotic blood perfusion changes in relation to TME and PME in a predominantly laparoscopic context.

Method

In this prospective cohort study, laser Doppler flowmetry was used to evaluate the perianastomotic colonic and rectal perfusion before and after surgery. The two surgical techniques were compared in terms of mean differences of perfusion units using a repeated measures ANOVA design, which also enabled interaction analyses between type of mesorectal excision and location of measurement. Anastomotic leakage until 90 days after surgery was reported for descriptive purposes.

Results

Some 28 patients were available for analysis: 17 TME and 11 PME patients. TME patients had a reduced blood perfusion postoperatively compared to PME patients in the aboral posterior area (mean difference: −57 vs 18 perfusion units; p = 0.010). An interaction between mesorectal excision type and anterior/posterior location was detected at the aboral level (p = 0.007). Two patients developed a minor leakage, diagnosed after discharge.

Conclusion

Patients operated on using TME have a decreased blood flow in the aboral posterior quadrant of the rectum postoperatively compared to patients operated on using PME. This might explain differing rates of anastomotic leakage.

Trial registration

ClinicalTrials.gov Identifier: NCT02401100

Lymphadenectomy Around Inferior Mesenteric Artery in Low-Tie vs High-Tie Laparoscopic Anterior Resection: Short- and Long-Term Outcome of a Cohort of 614 Rectal Cancers

Background

Preservation of the left colic artery in low-tie (LT) of inferior mesenteric artery remains controversial compared to high-tie (HT) in the colon and rectal cancers, for lymph node dissection, anastomotic leakage, and oncological outcome. This cohort study aims to analyze short- and long-term outcomes of laparoscopic anterior resections in LT vs HT for rectal cancers.

Methods

We analyzed a cohort of laparoscopic AR for RC from 2013 to 2016 at Renji Hospital, Shanghai, China. Short- and long-term outcome in LT vs HT group were compared for clinico-demographic characteristics, operative-time, lymph node dissection, short-term 30-day outcome, and long-term 3- and 5-year overall survival as well as disease-free survival. The x², t-test, and logistic regressions analysis were used and p<0.05 was considered significant.

Results

The cohort consisted of 614 laparoscopic AR with LT (236) and HT (378). The clinicodemographic characteristics were comparable among the groups. The surgery took longer in LT. The yield of LND was similar. Leakage occurred in 12.21% (n=75). Leakage was fewer in LT than HT, 8.89% vs 14.28%, p=0.047. The postoperative severe complications were higher in HT. The 30-day mortality was nil. The long-term 3- and 5-year overall survival and disease-free survival were similar in LT and HT.

Conclusion

The LT with preservation of left colic artery had similar lymph node yield, but lower leakage and complications than HT in laparoscopic anterior resections for rectal cancers. The long-term 3- and 5-year overall and disease-free survival were similar in the two groups.

Technical considerations depending on the level of vascular ligation in laparoscopic rectal resection

AIM

In addition to ischemia there is also anastomotic ends tension proven to be a risk factor for anastomotic leak. HT vascular ligation is accepted as a rule, in attempt to achieve tension-free anastomosis. LT is a preferred option, based on the more accurate preservation of proximal intestinal segment microperfusion and lower risk of damage to the hypogastric plexus. The aim of this study is evaluation of comparative indicators in high tie (HT) and low tie (LT) laparoscopic rectal resections.

METHODS

A prospective nonrandomized comparative cohort study of patients in our department with cancer of the rectum in clinical stage I-III, operated on in laparoscopic approach over a 6-years period.

RESULTS

For the period 2015-2020, a number of 208 laparoscopic surgeries have been done for rectal cancer. Patients were divided into three groups-group A with HT vascular ligation 116 pts. (69%), group B-53 pts. (25%), underwent low ligation-LT and group C-39pts. (19%) low tie plus lymph node dissection of the apical LN group (LT-appic LND). The distribution was made without randomization, based on the operators' expertise. Anastomotic leaks were 3.8% in group A, 3.0% in group B and 2.9% in group C (p > 0.05) with no significance difference. There is no significant difference in the number of lymph nodes obtained in group A and group B, while in group C the number of the harvested lymph nodes was higher (p < 0.05). The indicators for intestinal / defecation dysfunction, as well as for urinary/sexual dysfunction, according to our data, are significantly more favorable in patients with LT, in contrast to the other two groups.

CONCLUSION

HT vascular ligation attempts to achieve tension-free anastomosis and more harvested lymph nodes. However, LT could be a preferred option, based on the lack of significant evidence for a difference in specific oncological survival and due to more accurate preservation of proximal intestinal segment microperfusion to prevent anastomosis dehiscence, also for its lower risk of damage to the hypogastric plexus. Splenic flexure mobilization provides elongation of the proximal intestinal segment, but has no proven effect on anastomotic leakage incidence. It increases surgical duration and is in fact necessary in up to 30% of the cases. At the present moment there is no precise data whether LT has an advantage in terms of prevention of autonomic nervous and urogenital dysfunction. New prospective randomized and highly probative studies are needed to standardize the procedures in specific clinical situations.

The effect of different inferior mesenteric artery ligation levels and different lymph node dissection areas on the short- and long-term outcomes of rectal cancer

Background

Surgery is the most effective treatment for rectal cancer patients, but its key steps, including selection of the level of inferior mesenteric artery ligation and removal of 253 lymph nodes, are still inconclusive. This study aimed to analyze the effects of different surgical methods, including levels of ligation (low vs. high) and lymph node dissection areas (D2 vs. D3) on the short-term and long-term outcomes.

Methods

Between March 2014 and August 2018, 253 rectal cancer patients were retrospectively analyzed; 113 patients underwent low ligation D2 lymph node dissection (LLD2), 75 patients underwent low ligation D3 lymph node dissection (LLD3), and 65 patients underwent high ligation (HL). We compared the short-term and long-term outcomes among the different groups.

Results

There were no significant differences among the groups in terms of the intraoperative variables, including operative time, blood transfusion, and conversion from laparoscopic to open surgery. The median blood loss was significantly lower in LLD3 (50 mL) than in LLD2 (100 mL) and HL (100 mL), but it was not significantly different between LLD2 and HL. There were no significant differences among the LLD2, LLD3, and HL groups in the incidence of postoperative complications (9.7% vs. 12.0% vs. 10.8%, respectively) and hospital stay (14 vs. 15 vs. 14, respectively). The anastomotic leakage Clavien-Dindo grade was significantly lower with LLD2 and LLD3 than with HL, but it was the same between LLD2 and LLD3. The total number of lymph nodes harvested in the LLD3 group (n=14) was higher than that in the LLD2 group (n=12), but it was not significantly different than that in the HL group (n=13). There were no significant differences among the groups in terms of 3-year overall survival rate and disease-free survival rate.

Conclusions

Low ligation was similar to HL in terms of major intraoperative and postoperative parameters, but it can reduce the severity of anastomotic leakage to a certain extent. D3 lymph node dissection can increase the total number of lymph nodes harvested, but it did not improve long-term prognosis.

Analysis of Cumulative Fluid Balance Impact on the Stability of Gastrointestinal Tract Anastomosis

Anastomotic leakage is a serious postoperative complication following a low anterior resection of rectum. Current research in colorectal surgery focuses on searching for techniques which could minimize the risk of leakage. The main objective of this study was to evaluate the impact of cumulative fluid balance on microcirculatory changes at the anastomotic site.This experimental study used 15 domestic pigs; all of the animals underwent rectal resection. Then the animals were divided into three groups and received IV crystalloids at various rates, i.e. 5 ml/kg/h; 10 ml/kg/h; and 20 ml/kg/h. Large bowel micro-perfusion was measured using laser Doppler flowmetry during and following the surgical procedure.The experiments were successfully performed in all 15 cases. No animal died during the procedure or during the follow-up. We found no differences in micro-perfusion of the bowel between the experimental groups during the surgical procedure and during the follow-up period after the surgery. A significant decrease in micro-perfusion was observed after the transection of the inferior mesenteric artery in all the groups; again, no differences between the groups were observed.We did not confirm the original hypothesis that excessive load of IV crystalloids during the surgery would have a negative effect on bowel micro-perfusion and thus a negative effect on the healing of the anastomosis. However, laser Doppler flowmetry was found to have high accuracy in measuring tissue microcirculation and has the potential to be used in clinical practice.

High ligation of the inferior mesenteric artery and anastomotic leakage in anterior resection for rectal cancer: a systematic review and meta-analysis of randomized controlled trial studies

AIM

Surgeons have concerns whether high ligation (HL) of the inferior mesenteric artery (IMA) increases the incidence of anastomotic leakage (AL). This meta-analysis aimed to evaluate the influence of HL of the IMA on AL compared with low ligation (LL).

METHODS

PubMed, Embase, Web of Science, Cochrane Central Register of Controlled Trials and ClinicalTrials.gov databases were searched. Randomized controlled trial studies that compared HL with LL of the IMA in anterior resection for rectal cancer and reported AL outcomes were eligible for inclusion. The odds ratios and mean differences were analysed by a random-effects model. Trial sequential analysis was performed to minimize the risk of random errors. The Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach was used to evaluate the quality of evidence for outcomes.

RESULTS

Of the 531 records screened, five randomized controlled trials with 779 patients were selected for analysis. The pooled incidence of AL was 12.1% (95% Cl 7.77-18.26) in the HL group and 9.7% (95% Cl 5.79-15.82) in the LL group (OR 1.20, 95% CI 0.77-1.87, P = 0.42). In trial sequential analysis, the cumulative Z-score curve exceeded the futility boundary, although the required information size of 1060 had not been reached. The quality of evidence was judged to be high according to the GRADE approach.

CONCLUSIONS

This meta-analysis shows that HL of the IMA does not increase the incidence of AL in anterior resection for rectal cancer.

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.

Bowel surgery for endometriosis: A practical look at short- and long-term complications

Endometriosis involving the bowel requires a thorough evaluation prior to deciding upon surgical treatment. Patient symptoms, treatment goals, extent and location of disease, surgeon experience, and anticipated risks all play a part in the preoperative decision-making process. Short- and long-term complications after bowel surgery for endometriosis are the focus of this article. Unfortunately, the literature to date has inherent limitations that prevent generalizability. Most studies are retrospective or prospective single-center case series. Publication bias is unavoidable with mainly large volume experts sharing their experience. As a result, there is a need for high-quality prospective studies that standardize inclusion criteria and outcome measures among various centers with an aim to present long-term outcomes. In the meantime, care for those with endometriosis involving the bowel requires a thorough preoperative plan to minimize risks and a need for early diagnosis and management of complications unique to bowel surgery.

Low ligation has a lower anastomotic leakage rate after rectal cancer surgery

BACKGROUND

For laparoscopic rectal cancer surgery, the inferior mesenteric artery (IMA) can be ligated at its origin from the aorta [high ligation (HL)] or distally to the origin of the left colic artery [low ligation (LL)]. Whether different ligation levels are related to different postoperative complications, operation time, and lymph node yield remains controversial. Therefore, we designed this study to determine the effects of different ligation levels in rectal cancer surgery.

AIM

To investigate the operative results following HL and LL of the IMA in rectal cancer patients.

METHODS

From January 2017 to July 2019, this retrospective cohort study collected information from 462 consecutive rectal cancer patients. According to the ligation level, 235 patients were assigned to the HL group while 227 patients were assigned to the LL group. Data regarding the clinical characteristics, surgical characteristics and complications, pathological outcomes and postoperative recovery were obtained and compared between the two groups. A multivariate logistic regression analysis was performed to evaluate the possible risk factors for anastomotic leakage (AL).

RESULTS

Compared to the HL group, the LL group had a significantly lower AL rate, with 6 (2.8%) cases in the LL group and 24 (11.0%) cases in the HL group (P = 0.001). The HL group also had a higher diverting stoma rate (16.5% vs 7.5%, P = 0.003). A multivariate logistic regression analysis was subsequently performed to adjust for the confounding factors and confirmed that HL (OR = 3.599; 95%CI: 1.374-9.425; P = 0.009), tumor located below the peritoneal reflection (OR = 2.751; 95%CI: 0.772-3.985; P = 0.031) and age (≥ 65 years) (OR = 2.494; 95%CI: 1.080-5.760; P = 0.032) were risk factors for AL. There were no differences in terms of patient demographics, pathological outcomes, lymph nodes harvested, blood loss, hospital stay and urinary function (P > 0.05).

CONCLUSION

In rectal cancer surgery, LL should be the preferred method, as it has a lower AL and diverting stoma rate.

The median sacral artery in rectal blood supply: A cadaveric study

INTRODUCTION

Insufficient blood supply to the posterior rectal remnant after proctectomy is a possible mechanism for anastomotic leakage. The median sacral artery (MSA) is not generally considered to participate in the rectal blood supply, although some case studies have reported the rectum being supplied by it. The aim of this study is to elucidate the anatomy of the MSA in relation to the posterior rectal wall.

METHODS

Nineteen embalmed cadavers (12 males, seven females; mean age: 76 ± 9 years) were injected with a colored radio-opaque mixture in the aortic bifurcation, radiographed and subsequently dissected along the sacrum. The relationship between the MSA and the rectum was observed and the diameter of the MSA was measured 2 cm below the aortic bifurcation.

RESULTS

MSAs were identified in 16 (84.2%) of the 19 cadavers. Nine MSAs (47.4%) reached the rectal wall and penetrated it. MSAs that reached the posterior rectum took two different routes in the presacral space. Dissection and radiography showed four penetrating MSAs (21.1%) ending in a branching pattern and five (26.3%) as a tapering vessel. Seven MSAs (36.8%) did not reach the rectal wall. The mean MSA diameter was 1.98 ± 0.12 mm.

CONCLUSIONS

Almost half the MSAs reached and penetrated the posterior rectal wall, suggesting possible participation in the rectal blood supply. A large portion of the MSAs that penetrate the rectal wall run outside surgical margins and could continue to provide blood supply to the rectal remnant, potentially preventing anastomotic leakage.

Value of intra-operative Doppler sonographic measurements in predicting post-operative anastomotic leakage in rectal cancer: a prospective pilot study

BACKGROUND

Anastomotic leakage is a serious surgical complication in rectal cancer; however, effective evaluation methods for predicting anastomotic leakage individual risk in patients are not currently available. This study aimed to develop a method to evaluate the risk of leakage during surgery.

METHODS

The 163 patients with rectal cancer, who had undergone anterior resection and low-ligation procedures for Doppler sonographic hemodynamic measurement from April 2011 to January 2015 in Peking University Cancer Hospital, were prospectively recruited. A predictive model was constructed based on the associations between anastomotic leakage and alterations in the anastomotic blood supply in the patients, using both univariate and multivariate statistical analyses, as well as diagnostic methodology evaluation, including Chi-square test, logistic regression model, and receiver operating characteristic curve.

RESULTS

The overall anastomotic leakage incidence was 9.2% (15/163). Doppler hemodynamic parameters whose reduction was significantly associated with anastomotic leakage were peak systolic velocity, pulsatility index, and resistance index. The areas under the receiver operating characteristic curve of residual rates of peak systolic velocity, pulsatility index, and resistance index in predicting anastomotic leakage were 0.703 (95% confidence interval [CI]: 0.552-0.854), 0.729 (95% CI: 0.579-0.879), and 0.689 (95% CI: 0.522-0.856), respectively. The predictive model revealed that the patients with severely reduced blood-flow signal exhibited a significantly higher incidence rate of anastomotic leakage than those with sufficient blood supply (19.6% vs. 3.7%, P = 0.003), particularly the patients with low rectal cancer (25.9% vs. 3.9%, P = 0.007) and those receiving neoadjuvant chemoradiotherapy (32.1% vs. 3.7%, P = 0.001), independent of prophylactic ileostoma. Multivariate analysis revealed that insufficient blood supply of the anastomotic bowel was an independent risk factor for anastomotic leakage (odds ratio: 10.37, 95% CI: 2.703-42.735, P = 0.001).

CONCLUSION

Based on this explorative study, Doppler sonographic hemodynamic measurement of the anastomotic bowel presented potential value in predicting anastomotic leakage.

Spectrophotometric assessment of bowel perfusion during low anterior resection: a prospective study

Good perfusion of the bowel and a tension-free anastomosis are the two main prerequisites for an uneventful anastomotic healing in rectal surgery. This prospective cohort study investigates the noninvasive intraoperative spectrophotometric assessment of the bowel perfusion using a device called “Oxygen to See” (O2C^®). Forty patients, planned for low anterior resection, were prospectively enrolled in this study to undergo an intraoperative spectrophotometric assessment of the bowel. Three different O2C^® parameters were collected from the colonic and the rectal stumps before fashioning the anastomosis: SO2 (capillary venous oxygen saturation), rHb (relative hemoglobin amount), and flow (blood flow velocity). Bowel perfusion was also assessed with the cold-steel-test (CST), which involves severing the colic marginal artery of Drummond at the tip of the colon stump. The data collected from the spectrophotometric measurement and the CST were analyzed for correlation of both methods with respect to each other and to the outcome of the anastomosis. Nine patients were excluded due to different reasons, thus leaving 31 patients for statistical analysis. Three flow parameters collected at the colonic stump significantly predicted an anastomotic leak (p: 0.0057; p: 0.0250; p: 0.0404). One rHb parameter collected at the rectal stump correlated weakly with the anastomotic outcome (p: 0.0768). The CST did not correlate significantly with anastomotic leak (p: 0.1195), but showed significant correlations to some rHb values. Intraoperative noninvasive spectrophotometric measurement is feasible and could be a useful method in assessing bowel perfusion before fashioning a colorectal anastomosis.

A nationwide study on the incidence of mesenteric ischaemia after surgery for rectal cancer demonstrates an association with high arterial ligation

AIM

The incidence of mesenteric ischaemia after resection for rectal cancer has not been investigated in a population-based setting. The use of high ligation of the inferior mesenteric artery might cause such ischaemia, as the bowel left in situ depends on collateral blood supply after a high tie.

METHOD

The Swedish Colorectal Cancer Registry was used to identify all patients subjected to an abdominal resection for rectal cancer during the years 2007-2017 inclusive. Mesenteric ischaemia within the first 30 postoperative days was recorded, classified as either stoma necrosis or colonic necrosis. Multivariable logistic regression was used to estimate odds ratios (ORs) with 95% confidence intervals (CIs) for mesenteric ischaemia in relation to high tie, with adjustment for confounding.

RESULTS

Some 14 657 patients were included, of whom 59 (0.40%) had a reoperation for any type of mesenteric ischaemia, divided into 34 and 25 cases of stoma necrosis and colonic necrosis, respectively. Compared with patients who did not require reoperation for mesenteric ischaemia following rectal cancer surgery, the proportion having high tie was greater (54.2% vs 38.5%; P = 0.032). The adjusted OR for reoperation due to any mesenteric ischaemia with high tie was 2.26 (95% CI 1.34-3.79), while the corresponding estimates for stoma and colonic necrosis, respectively, were 1.60 (95% CI 0.81-3.17) and 3.69 (95% CI 1.57-8.66).

CONCLUSION

The incidence of reoperation for mesenteric ischaemia after abdominal resection for rectal cancer is low, but the use of a high tie might increase the risk of colonic necrosis demanding surgery.

Lymph node yield, survival benefit, and safety of high and low ligation of the inferior mesenteric artery in colorectal cancer surgery: a systematic review and meta-analysis

PURPOSE

The aim of this meta-analysis was to compare high inferior mesenteric artery (IMA) ligation (HL) with low IMA ligation (LL) for the treatment of colorectal cancer and to evaluate the lymph node yield, survival benefit, and safety of these surgeries.

METHODS

PubMed, Embase, Cochrane Library, Web of Science, and China Biomedical Literature Database (CBM) were systematically searched for relevant articles that compared HL and LL for sigmoid or rectal cancer. We calculated the odds ratio (OR) with 95% confidence intervals (CIs) for dichotomous outcomes and the weighted mean difference (WMD) for continuous outcomes.

RESULTS

In total, 30 studies were included in this analysis. There were significantly higher odds of anastomotic leakage and urethral dysfunction in patients treated with HL compared to those treated with LL (OR = 1.29; 95% CI = 1.08 to 1.55; OR = 2.45; 95% CI = 1.39 to 4.33, respectively). There were no significant differences between the groups in terms of the total number of harvested lymph nodes, the number of harvested lymph nodes around root of the IMA, local recurrence rate, and operation time. Further, no statistically significant group differences in 5-year overall survival rates and 5-year disease-free survival rates were detected among all patients nor among subgroups of stage II patients and stage III patients, respectively.

CONCLUSIONS

LL can achieve equivalent lymph node yield to HL, and both procedures have similar survival benefits. However, LL is associated with a lower incidence of leakage and urethral dysfunction. Thus, LL is recommended for colorectal cancer surgery.

Preservation versus non-preservation of left colic artery in colorectal cancer surgery: An updated systematic review and meta-analysis

BACKGROUND

It remains unclear whether or not preservation of the left colic artery (LCA) for colorectal cancer surgery. The objective of this updated systematic review and meta-analysis is to evaluate the current scientific evidence of LCA non-preservation versus LCA preservation in colorectal cancer surgery.

METHODS

A systematic search was conducted in the Medline, Embase, PubMed, Cochrane Library, ClinicalTrials, Web of Science, China National Knowledge Infrastructure and Chinese BioMedical Literature Database, and reference without limits. Quality of studies was evaluated by using the Newcastle-Ottawa scale and the Cochrane Collaboration's tool for assessing the risk of bias. Effective sizes were pooled under a random- or fixed-effects model. The funnel plot was used to assess the publication bias. The outcomes of interest were oncologic consideration including the number of apical lymph nodes, overall recurrence, 5-years overall survival, and 5-years disease-free survival (DFS); safety consideration including overall 30-day postoperative morbidity and overall 30-day postoperative mortality; anatomic consideration including anastomotic circulation, anastomotic leakage, urogenital, and defaecatory dysfunction.

RESULTS

Twenty-four studies including 4 randomized controlled trials (RCTs) and 20 cohort studies with a total of 8456 patients (4058 patients underwent LCA non-preservation surgery vs 4398 patients underwent LCA preservation surgery) were enrolled in this meta-analysis. The preservation of LCA was associated with significantly less anastomotic leakage (odds ratio 1.23, 95% confidence interval 1.02-1.48, P = .03). In term of sexual dysfunction, urinary retention, the number of apical lymph nodes, and long-term oncologic outcomes, there were no significant differences between the LCA non-preservation and LCA preservation group. It was hard to draw definitive conclusions on other outcomes including operation time, blood loss, the first postoperative exhaust time, and perioperative morbidity and mortality for insufficient data and highly significant heterogeneity among studies.

CONCLUSIONS

The pooled data provided evidence to support the LCA preservation preferred over LCA non-preservation in anastomotic leakage. Future more large-volume, well-designed RCTs with extensive follow-up are needed to draw a definitive conclusion on this dilemma.

Comparison of complexity and spectral indices of skin-surface laser-doppler signals in patients with breast cancer receiving chemotherapy and Kuan-Sin-Yin

This study tested the hypothesis that measuring and analyzing skin-surface blood flow dynamics can be used to noninvasively discriminate the different microcirculatory and physiological function states of breast-cancer patients with chemotherapy between receiving and not receiving Kuan-Sin-Yin (KSY) treatment. The 17 included patients were assigned randomly to 2 comparison groups: Group K (n = 10) received KSY treatment, while Group NK (n = 7) did not receive KSY treatment. Beat-to-beat, spectral, and approximate-entropy (ApEn) analyses were applied to the 20-minute laser-Doppler sequences. The self-reported quality of life and cancer-related symptoms of patients were also investigated. In posttests, Group NK had a significantly larger ApEn ratio than that in Group K, significantly smaller values of laser-Doppler-flowmetry variability indices, and a slightly higher relative energy contribution of the neural-related frequency band compared to those in the pretests. Almost all cancer-related symptoms showed improvements in Group K compared to in Group NK. The present findings indicated that the present analysis can be used to detect the significantly different responses in the laser-Doppler indices between taking and not taking KSY. The KSY effect was also noted to be accompanied with improvement of EORTC QLQ-C30 scores. These could lead to a rapid, inexpensive, and objective technique for enhancing clinical applications in quality-of-life monitoring of breast cancer therapy.

Evaluation of the clinical efficacy of preserving the left colic artery in laparoscopic resection for rectal cancer: A meta-analysis

The aim of the present meta-analysis compared left colic artery (LCA) preservation with non-preservation in laparoscopic resection of rectal cancer in terms of feasibility, efficacy and safety. The PubMed, Ovid, Embase, Web of Science, CBM, CNKI, VIP and WanFang Data databases were searched prior to June 2017 for studies comparing LCA preservation and non-preservation in laparoscopic resection for rectal cancer. Two researchers screened the literature independently, extracted the data and evaluated the risk of bias. The study was performed using RevMan 5.3 software for meta-analysis. A total of 10 studies comparing LCA preservation and non-preservation in laparoscopic resection for rectal cancer were selected for this meta-analysis, with a combined study population of 1,471 patients. The results of the meta-analysis demonstrated that, when comparing LCA preservation with non-preservation in laparoscopic resection for rectal cancer, there were significant differences between the two groups in terms of operative time (P<0.01), estimated blood loss (P<0.01), percentage of neostomy (P<0.01), the number of retrieved lymph nodes (P<0.01), time to first postoperative exhaust (P<0.01) and amount of anastomotic leakage (P<0.01). However, there were no significant differences in postoperative hospital stay (P=0.28), incidence of recurrence (P=0.73) and incidence of metastasis (P=0.52). Therefore, compared with LCA non-preservation, patients in whom the LCA was preserved during laparoscopic resection for rectal cancer had a better prognosis. However, there was no difference in recurrence or metastasis between the two groups. Although the operative time and estimated blood loss were increased with LCA preservation, these may be reduced with improving proficiency of the operating surgeons. The conclusions of the present study require verification by larger samples and high-quality randomized controlled trials.

High ligation of the inferior mesenteric artery during sigmoid colon and rectal cancer surgery increases the risk of anastomotic leakage: a meta-analysis

BACKGROUND

The ideal level of ligation of the inferior mesenteric artery (IMA) during curative resection of sigmoid colon and rectal cancer is still controversial. The aim of this meta-analysis was to examine the impact of high ligation and low ligation of the IMA on anastomotic leakage, overall morbidity, postoperative mortality, and oncological outcomes in patients undergoing surgery for sigmoid colon and rectal cancer.

METHODS

PubMed, EMBASE, Web of Science, and BioMed Central databases were searched to identify relevant articles published from May 1953 to March 2018. A total of 18 articles (14 non-randomized studies and 4 randomized clinical trials) were identified. Review Manager 5.3 software was used for analysis of data. The pooled odds ratio (OR) and weighted mean difference (WMD), with 95% CI, were calculated using either the fixed effects model or random effects model.

RESULTS

Of the 5917 patients included in this meta-analysis, 3652 patients underwent low ligation of the IMA and 2265 patients underwent high ligation of the IMA. Anastomotic leakage rate was 9.8% in high ligation patients vs. 7.0% in low ligation patients; the risk of anastomotic leakage was significantly higher in high ligation patients (OR = 1.33; 95% CI 1.10-1.62; P = 0.004). What is more, overall morbidity was also significantly higher in high ligation patients (OR = 1.39; 95% CI, 1.05-1.68; P = 0.05). Postoperative mortality, number of harvested lymph nodes, overall recurrence rate, and 5-year survival rate did not differ significantly between the two groups.

CONCLUSION

Low ligation of the IMA during curative resection of sigmoid colon and rectal cancer appears to be associated with lower risk of anastomotic leakage and overall morbidity. However, there was no significant advantage of low ligation over high ligation of IMA in terms of postoperative mortality, the number of harvested lymph nodes, overall recurrence rate, or 5-year survival rate.

Preservation versus non-preservation of left colic artery in sigmoid and rectal cancer surgery: A meta-analysis

BACKGROUND

The aim of this study was to conduct a meta-analysis comparing the oncological, intraoperative and safety outcomes in sigmoid and rectal cancer surgery with and without preservation of the left colic artery (LCA).

METHOD

We searched Medline, Embase, China National Knowledge Infrastructure (CNKI), and PubMed databases for relevant articles published between 1962 and 2017. Randomized and non-randomized clinical trials were identified and included in the study. End-points evaluated included 5-year mortality, number of patients with retrieved positive metastatic lymph nodes (LN) at the root of inferior mesenteric artery (IMA), number of retrieved LNs, morbidity, mortality, recurrence, bowel obstruction, intraoperative blood loss, anastomotic leakage, operation time, surgical site infection and postoperative bleed. Meta-analysis was conducted using RevMan 5.3 software. The odds ratio (OR) with 95% confidence intervals (CI) was used to analyze dichotomous data.

RESULTS

Seventeen studies including 6247 patients were identified for the meta-analysis. Meta-analysis revealed that preserving the LCA was associated with reduced anastomotic leakage rate (OR, 0.78; 95% CI, 0.62-0.98; P = 0.03). There were no significant differences between the two groups with respect to the 5-year mortality, number of retrieved LNs, number of patients with retrieved positive metastatic LNs at the root of IMA, morbidity, mortality, recurrence, bowel obstruction, intraoperative blood loss, operation time, surgical site infection and postoperative bleed.

CONCLUSION

In comparison with ligating the left colic artery, preserving the left colic artery seems to achieve comparable success with acceptable safety outcomes and we suggest to preserve the LCA in the sigmoid and rectal cancer surgeries. However, more multicenter randomized controlled trials are required to further evaluate the efficacy and safety of preserving the left colic artery in surgeries.

Anastomotic leakage in rectal cancer surgery: The role of blood perfusion

Anastomotic leakage after anterior resection for rectal cancer remains a common and often devastating complication. Preoperative risk factors for anastomotic leakage have been studied extensively and are used for patient selection, especially whether to perform a diverting stoma or not. From the current literature, data suggest that perfusion in the rectal stump rather than in the colonic limb may be more important for the integrity of the colorectal anastomosis. Moreover, available research suggests that the mid and upper rectum is considerably more vascularized than the lower part, in which the posterior compartment seems most vulnerable. These data fit neatly with the observation that anastomotic leaks are far more frequent in patients undergoing total compared to partial mesorectal excision, and also that most leaks occur dorsally. Clinical judgment has been shown to ineffectively assess anastomotic viability, while promising methods to measure blood perfusion are evolving. Much interest has recently been turned to near-infrared light technology, enhanced with fluorescent agents, which enables intraoperative perfusion assessment. Preliminary data are promising, but large-scale controlled trials are lacking. With maturation of such technology, perfusion measurements may in the future inform the surgeon whether anastomoses are at risk. In high colorectal anastomoses, anastomotic revision might be feasible, while a diverting stoma could be fashioned selectively instead of routinely for low anastomoses.