Safe anastomosis in laparoscopic and robotic low anterior resection for rectal cancer: a narrative review and outcomes study from an expert tertiary center

Quantification of indocyanine green fluorescence angiography in colorectal surgery: a systematic review of the literature

BACKGROUND

Indocyanine green fluorescence angiography (ICGFA) during colorectal surgery associates with reduced post-operative anastomotic complication rates. Because its interpretation is subjective, quantification has been proposed to address inter-user variability. This study reviews the published literature regarding ICGFA quantification during colorectal surgery with a focus on impactful clinical deployment.

METHODS

A systematic review was performed of English language publications regarding clinical studies of ICGFA quantification in colorectal surgery in PubMed, Scopus, Web of Science and Cochrane Library on 29th August 2024, updated to 18th November 2024, following PRISMA guidelines. Newcastle Ottawa scale (NOS) was used to assess quality.

RESULTS

A total of 1428 studies were screened with 22 studies (1469 patients) selected. There was significant heterogeneity of ICGFA methodology, quantification methods and parameter selection and only three studies were NOS "high" quality. Extracorporeal application was most common. Four studies (154 patients) conducted real-time ICGFA analyses (others were post hoc) and four utilised artificial intelligence methods. Eleven studies only included patients undergoing left-sided resection (six focusing specifically on rectal resections). Only one study employed the quantification method to guide intra-operative decision-making regarding colonic transection. Twenty-six different perfusion parameters were assessed, with time from injection to visible fluorescence and maximum intensity the most commonly (but not only) correlated parameters regarding anastomotic complication (n = 18). Other grounding correlates were tissue oxygenation (n = 3, two with hyperspectral imagery), metabolites (n = 2) and surgeon interpretation (n = 5).

CONCLUSION

Quantification of the ICGFA signal for colorectal surgery is feasible but has so far seen limited academic advancement beyond feasibility.

Impact of indocyanine green fluorescence angiography on surgeon action and anastomotic leak in colorectal resections. A systematic review and meta-analysis

BACKGROUND

Indocyanine green fluorescence angiography (ICGFA) during colorectal surgery either reassures surgeons regarding intestinal perfusion sufficiency or prompts changed surgical strategy by indicating unsuspected insufficiency. This study describes existing evidence supporting ICGFA use in colorectal surgery, particularly regarding impact on intraoperative decisions.

METHODS

Searches were performed on PubMed, ScienceDirect, Scopus, Web of Science, Cochrane Collaboration databases on 5th December 2023, updated to 19th August 2024. Full English language publications of clinical studies in human patients undergoing colorectal resection with primary anastomosis with the use of ICGFA to assess bowel perfusion intraoperatively, with a control group, were included. Pooling of anastomotic leak (AL) rates was performed for primary outcome analysis with odds ratio (OR) and number-needed-to-treat (NNT) calculated regarding leak reduction.

RESULTS

45 studies comprising 14,333 patients were included, with 7 randomised controlled trials (2911 patients). Overall, AL rate was 6.8%, 4.5% with ICGFA and 8.5% without (OR:0.47, p < 0.001, NNT 23), increasing to 9.5%, 7.5% and 11.6%, respectively, in randomised controlled trials (OR:0.62, p < 0.01, NNT 25). In rectal resections, AL rate was 4.7% with ICGFA vs 11.5% without (OR: 0.38, p < 0.0001). 26 studies performed ICGFA before and after anastomosis formation and 19 used ICGFA only prior to bowel transection, with no significant difference of AL rate reduction on subgroup testing. ICGFA prompted a change in surgical plan in 8.4% of thirty-four studies reporting this. Interestingly, in these studies, leak rates overall were 3.7% when ICGFA matched surgeon judgement versus 5.7% when it prompted change (OR 0.51, p < 0.0025), versus 7.7% without (OR 0.45, p < 0.0001). In rectal resections, these figures were 5%, 8.8% (OR 0.42, p = 0.01) and 12.0% (OR0.39, p < 0.0001), respectively.

CONCLUSIONS

ICGFA colorectal perfusion assessment is associated with lower anastomotic leak rates, especially when confirming surgeons' judgement, and may so stratify patients post-operatively regarding subsequent anastomotic leak rate.

Impact of diversion ileostomy on postoperative complications and recovery in the treatment of locally advanced upper-half rectal cancer

The efficacy of diversion ileostomy followed by radical surgery for locally advanced upper-half rectal cancer remains uncertain. This study seeks to compare the effectiveness of treatment with and without diversion ileostomy in preventing anastomotic leakage (AL) and to identify a subset who may benefit from diversion ileostomy after AL occurs in Chinese patients with stage II and III upper-half rectal cancer. A retrospective study enrolled a total of 809 patients with locally advanced upper-half rectal cancer between 2017 and 2021, with 27.6% (n = 223) treated with diversion ileostomy and 72.4% (n = 586) treated without diversion ileostomy. The Diversion(+) group (n = 172) and Diversion(-) group (n = 172) were compared for perioperative outcomes through 1:1 propensity score matching (PSM). The selection of variables for multivariable logistic regression was determined through bivariate logistic regression analysis. Additionally, optimal cutoff values for risk factors were identified using ROC curve analysis. Within the entire cohort, patients in the Diversion(+) group exhibited a lower distance from the anal verge (DAV) and higher rates of chemoradiotherapy (CRT), diabetes, cN2 stage, mrCRM positivity, EMVI positivity, and CEA elevation compared to those in the Diversion(-) group. Following PSM, a satisfactory balance of baseline variables was achieved between the two groups. There were no statistically significant differences in AL rates (7.0% vs. 5.8%, p = 0.659) or AL grade distribution (Grade A: 0.6% vs. 0%, Grade B: 5.2% vs. 4.1%, Grade C: 1.2% vs. 1.7%, p = 0.691) between the two groups. However, the Diversion(+) group demonstrated a higher incidence of postoperative complications (30.8% vs. 17.4%, p = 0.004), Clavien‒Dindo III-IV complications (2.9% vs. 2.3%, p = 0.013), particularly wound infections (8.1% vs. 1.2%, p = 0.002), and early postoperative inflammatory small bowel obstruction (EPISBO) (8.7% vs. 1.2%, p = 0.001) compared to the Diversion(-) group. Results from multivariate logistic regression analysis revealed that male gender (OR = 2.354, p = 0.014) was the only independent risk factor associated with AL, while the presence of diversion ileostomy (with vs. without, OR = 1.144, p = 0.686) did not show significant associations. In patients with AL, the onset of the AL was observed to occur later in the Diversion(+) group compared to the Diversion(-) group (7.0 ± 3.3 vs. 3.4 ± 1.4 days, p < 0.001), while the recovery time was significantly shorter (11.3 ± 4.7 vs. 20.3 ± 7.2 days, p < 0.001). Similarly, in Grade C AL patients, the occurence time was delayed in the Diversion(+) group compared to the Diversion(-) group (8.7 ± 4.7 vs. 3.2 ± 1.5 days, p = 0.008), with a shorter recovery time (19.3 ± 2.1 vs. 25.7 ± 6.7 days, p = 0.031). A trend was observed indicating a longer interval before ileostomy restoration in the AL patients compared to the non-AL patients (7.6 ± 4.9 months vs. 5.5 ± 2.9 months, p = 0.079). In addition, DAV (OR = 0.078, p = 0.002) was identified as the only independent factor associated with potential-diversion-benefit in patients with AL, with an optimal cutoff point of 8.6 cm. The utilization of diversion ileostomy as a preventative measure for AL in cases of locally advanced upper-half rectal cancer is not universally endorsed due to potential complications such as small bowel obstruction and wound infection. Nevertheless, in the occurrence of AL, diversion ileostomy may prove advantageous for patient recuperation. Particularly, male patients with a DAV ranging from 7 to 8.6 cm may experience benefits from undergoing diversion ileostomy subsequent to AL in cases of locally advanced upper-half rectal cancer.

Preoperative risk factors and cumulative incidence of temporary ileostomy non-closure after sphincter-preserving surgery for rectal cancer: a meta-analysis

BACKGROUND

Temporary ileostomy (TI) has proven effective in reducing the severity of anastomotic leakage after rectal cancer surgery; however, some ileostomies fail to reverse over time, leading to conversion into a permanent stoma (PS). In this study, we aimed to investigate the preoperative risk factors and cumulative incidence of TI non-closure after sphincter-preserving surgery for rectal cancer.

MATERIALS AND METHODS

We conducted a meta-analysis after searching the Embase, Web of Science, PubMed, and MEDLINE databases from their inception until November 2023. We collected all published studies on the risk factors related to TI non-closure after sphincter-preserving surgery for rectal cancer.

RESULTS

A total of 1610 studies were retrieved, and 13 studies were included for meta-analysis, comprising 3026 patients. The results of the meta-analysis showed that the identified risk factors included older age (p = 0.03), especially > 65 years of age (p = 0.03), male sex (p = 0.009), American Society of Anesthesiologists score ≥ 3 (p = 0.004), comorbidity (p = 0.001), and distant metastasis (p < 0.001). Body mass index, preoperative hemoglobin, preoperative albumin, preoperative carcinoma embryonic antigen, tumor location, neoadjuvant chemoradiotherapy, smoking, history of abdominal surgery, and open surgery did not significantly change the risk of TI non-closure.

CONCLUSION

We identified five preoperative risk factors for TI non-closure after sphincter-preserving surgery for rectal cancer. This information enables surgeons to identify high-risk groups before surgery, inform patients about the possibility of PS in advance, and consider performing protective colostomy or Hartmann surgery.

Clinical Outcomes of Ileostomy Closure during versus after Adjuvant Chemotherapy in Patients with Rectal Cancer

Background

Protective ileostomy can effectively prevent severe anastomotic leakage after rectal cancer surgery; however, the optimal timing for ileostomy closure during adjuvant chemotherapy remains unclear. This study aimed to explore the safety and long-term outcomes of early ileostomy closure during adjuvant chemotherapy.

Method

Patients who underwent laparoscopic rectal cancer surgery combined with protective ileostomy and adjuvant chemotherapy between April 2017 and April 2021 were retrospectively evaluated. Patients were divided into an early closure group during chemotherapy (group A) and a late closure group after chemotherapy (group B).

Results

A total of 215 patients were included in this study, with 115 in group A and 100 in group B. There were no significant differences in demographic and clinical characteristics between the two groups. In group A, durations of stoma status (p < 0.001) and low anterior resection syndrome (LARS) (p < 0.001) were shorter, and rectal stenosis (p=0.036) and stoma-related complications (p=0.007), especially stoma stenosis (p=0.041), were less common. However, compliance with chemotherapy was worse (p=0.009). There were no significant differences in operative time, postoperative hospital stay, postoperative complications, incidence and severity of LARS, disease-free survival, or overall survival between groups.

Conclusion

Early ileostomy closure can effectively reduce the duration of stoma status, duration of LARS, rectal stenosis, and stoma-related complications while not affecting surgical complications and oncological outcomes. Ileostomy closure should not be delayed because of adjuvant chemotherapy. However, follow-up should be strengthened to increase compliance and integrity with chemotherapy.

Risk factors for anastomotic stenosis after radical resection of rectal cancer: A systematic review and meta-analysis

Radical resection of rectal cancer is a safe and effective treatment, but there remain several complications related to anastomosis. We aimed to assess the risk factors and incidence of rectal anastomotic stenosis (AS) after rectal cancer resection. We conducted a systematic review and meta-analysis after searching PubMed, Embase, Web of Science, and Medline databases from inception until May 2023. Data are reported as the combined odds ratio (OR) for categorical variables and the weighted mean difference (WMD) for continuous variables. Six hundred and fifty-nine studies were retrieved, nine (3031 patients) of which were included in the meta-analysis. Young age (WMD = -3.09, P = 0.0002), male sex (OR = 1.53, P = 0.0002), smoking (OR = 1.54, P = 0.009), radiotherapy (OR = 2.34, P = 0.0002), protective stoma (OR = 2.88, P = 0.007), intersphincteric resection surgery (OR = 6.28, P = 0.05), anastomotic fistula (OR = 3.72, P = 0.003), and anastomotic distance (WMD = -3.11, P = 0.0006) were identified as factors that increased the risk of AS, while staple (OR = 0.39, P < 0.001) was a protective factor. The incidence of AS after rectal cancer resection was approximately 17% (95% CI: 13%-21%). We identified eight risk factors and one protective factor associated with AS after rectal cancer resection. These factors may be combined in future studies to develop a more comprehensive and accurate prediction model related to AS after rectal cancer resection.

Self-expanding metal stent placement and pathological alterations among obstructive colorectal cancer cases

BACKGROUND

Experimental studies suggest that self-expanding metal stents (SEMSs) enhance the aggressive behavior of obstructive colorectal cancer. The influence of SEMS placement on pathological alterations remains to be elucidated.

AIM

To determine whether SEMS placement is associated with molecular or pathological features of colorectal carcinoma tissues.

METHODS

Using a nonbiased molecular pathological epidemiology database of patients with obstructive colorectal cancers, we examined the association of SEMS placement with molecular or pathological features, including tumor size, histological type, American Joint Committee on Cancer (AJCC)-pTNM stage, and mutation statuses in colorectal cancer tissues compared with the use of transanal tubes. A multivariable logistic regression model was used to adjust for potential confounders.

RESULTS

SEMS placement was significantly associated with venous invasion (P < 0.01), but not with the other features examined, including tumor size, disease stage, mutation status, and lymphatic invasion. In both the univariable and multivariable models with adjustment for potential factors including tumor location, histological type, and AJCC-pT stage, SEMS placement was significantly associated with severe venous invasion (P < 0.01). For the outcome category of severe venous invasion, the multivariable odds ratio for SEMS placement relative to transanal tube placement was 19.4 (95% confidence interval: 5.24–96.2). No significant differences of disease-free survival and overall survival were observed between SEMS and transanal tube groups.

CONCLUSION

SEMS placement might be associated with severe venous invasion in colorectal cancer tissue, providing an impetus for further investigations on the pathological alterations by SEMSs in colorectal cancer development.

Postoperative complications after robotic resection of colorectal cancer: An analysis based on 5-year experience at a large-scale center

BACKGROUND

As a common gastrointestinal malignancy, colorectal cancer (CRC) poses a serious health threat globally. Robotic surgery is one of the future trends in surgical treatment of CRC. Robotic surgery has several technical advantages over laparoscopic surgery, including 3D visualization, elimination of the fulcrum effect, and better ergonomic positioning, which together lead to better surgical outcomes and faster recovery. However, analysis of independent factors of postoperative complications after robotic surgery is still insufficient.

AIM

To analyze the incidence and risk factors for postoperative complications after robotic surgery in patients with CRC.

METHODS

In total, 1040 patients who had undergone robotic surgical resection for CRC between May 2015 and May 2020 were analyzed retrospectively. Postoperative complications were categorized according to the Clavien-Dindo (C-D) classification, and possible risk factors were evaluated.

RESULTS

Among 1040 patients who had undergone robotic surgery for CRC, the overall, severe, local, and systemic complication rates were 12.2%, 2.4%, 8.8%, and 3.5%, respectively. Multivariate analysis revealed that multiple organ resection (P < 0.001) and level III American Society of Anesthesiologists (ASA) score (P = 0.006) were independent risk factors for overall complications. Multivariate analysis identified multiple organ resection (P < 0.001) and comorbidities (P = 0.029) as independent risk factors for severe complications (C-D grade III or higher). Regarding local complications, multiple organ resection (P = 0.002) and multiple bowel resection (P = 0.027) were independent risk factors. Multiple organ resection (P < 0.001) and level III ASA score (P = 0.007) were independent risk factors for systemic complications. Additionally, sigmoid colectomy had a lower incidence of overall complications (6.4%; P = 0.006) and local complications (4.7%; P = 0.028) than other types of colorectal surgery.

CONCLUSION

Multiple organ resection, level III ASA score, comorbidities, and multiple bowel resection were risk factors for postoperative complications, with multiple organ resection being the most likely.

Redefining the collateral system between the superior mesenteric artery and inferior mesenteric artery: a novel classification

AIM

The aim of this study was to evaluate the arterial collateral vasculature between the superior mesenteric artery and the inferior mesenteric artery (IMA) from a surgical perspective.

METHOD

A total of 107 fresh adult cadavers (94 male) were studied with emphasis on the vascular anatomy of the left colon. Dissections were carried out mimicking the anterior resection technique. The vasculature of the left mesocolon and the collaterals between the superior mesenteric artery and the IMA with respect to their relationship to the inferior mesenteric vein (IMV) were assessed and classified. Collaterals were classified into three different groups: marginal anastomoses (via the marginal = pericolic artery), intermediate mesocolic anastomoses (parallel to the marginal artery but neither adjacent to the IMV nor close to the duodenum) and central mesocolic anastomoses (next to the IMV at the level of the duodenojejunal junction and the lower border of the pancreas).

RESULTS

All patients had a marginal anastomosis. However, the marginal anastomosis, as the only anastomosis between the superior and inferior mesenteric arteries at the splenic flexure, was observed in 41 cases (38%). In addition to the marginal artery, intermediate mesocolic anastomoses were found in 49 (46%) and a central mesocolic anastomosis was observed in 17 (16%) of the 107 cases in the splenic flexure mesocolon. It is in this latter variant that collateral vessels can be compromised during ligation/transection of the IMV.

CONCLUSION

This new classification can contribute to a precise mesocolic dissection technique and splenic flexure mobilization and help prevent ischaemic damage to the descending colon.

Optimal Complete Rectum Mobilization Focused on the Anatomy of the Pelvic Fascia and Autonomic Nerves: 30 Years of Experience at Severance Hospital

The primary goal of surgery for rectal cancer is to achieve an oncologically safe resection, i.e., a radical resection with a sufficient safe margin. Total mesorectal excision has been introduced for radical surgery of rectal cancer and has yielded greatly improved oncologic outcomes in terms of local recurrence and cancer-specific survival. Along with oncologic outcomes, functional outcomes, such as voiding and sexual function, have also been emphasized in patients undergoing rectal cancer surgery to improve quality of life. Intraoperative nerve damage or combined excision is the primary reason for sexual and urinary dysfunction. In the past, these forms of damage could be attributed to the lack of anatomical knowledge and poor visualization of the pelvic autonomic nerve. With the adoption of minimally invasive surgery, visualization of nerve structure and meticulous dissection for the mesorectum are now possible. As the leading hospital employing this technique, we have adopted minimally invasive platforms (laparoscopy, robot-assisted surgery) in the field of rectal cancer surgery and standardized this technique globally. Here, we review a standardized technique for rectal cancer surgery based on our experience at Severance Hospital, suggest some practical technical tips, and discuss a couple of debatable issues in this field.

The safety and efficacy of laparoscopic surgery versus laparoscopic NOSE for sigmoid and rectal cancer

BACKGROUND

Laparoscopic surgery with natural orifice specimen extraction (La-NOSE) is being performed more frequently for the minimally invasive management of sigmoid and rectal cancer. The objective of this meta-analysis was to compare the clinical and oncological safety and efficacy of La-NOSE versus conventional laparoscopy (CL).

METHODS

A search of the PubMed, Web of Science, and Cochrane databases was performed for studies that compared clinical or oncological outcomes of conventional laparoscopic resection using NOSE with conventional laparoscopic resection for sigmoid and rectal cancer.

RESULTS

Compared with CL group, the length of hospital stay and the pain score on the first day were shorter in the La-Nose group. The La-NOSE group had a lower incidence of total perioperative complications (OR 0.46; 95% CI [0.32 to 0.66]; I² = 0%; P < 0.0001) and a lower incidence of surgical site infections (SSIs) (OR 0.11; 95% CI [0.04 to 0.29]; I² = 0%; P < 0.0001) than the CL group, while the anastomotic leakage showed no significant difference between the La-Nose group and the CL group (P = 0.19). 5-year disease-free survival (DFS) and 5-year overall survival (OS) were no significant difference between the La-Nose group and the CL group (P = 0.43, P = 0.40, respectively).

CONCLUSIONS

La-NOSE can achieve oncological and surgical safety comparable to that of CL for patients with sigmoid and rectal cancer. La-NOSE in patients was associated with a shorter hospital stay, shorter time to first flatus or defecation, less postoperative pain, and fewer surgical site infections (SSIs) and total perioperative complications. In general, the operative time in La-NOSE was longer than that in CL. The long-term oncological efficacy of La-NOSE seems to be equivalent to that of CL.

Prospective Study Comparing Clinical vs Indocyanine Green Fluorescence-Based Assessment of Line of Transection in Robotic Rectal Cancer Surgery-Indian Study

Anastomotic leakage continues to be the most feared postoperative complications in rectal surgery with negative impact on both short- and long-term outcomes. Fortunately, new surgical strategies have helped to offset this complication and improve surgical outcomes. Traditionally, perfusion is assessed by intraoperative visual judgment by the surgeon. These subjective methods lack predictive accuracy resulting in either excess or insufficient colonic resection. Indocyanine green (ICG) fluorescence has shown promise in identifying the adequacy of perfusion. After injection of ICG, the system projected high-resolution near-infrared real-time images of blood flow in mesentery and bowel wall. This novel imaging method is used intraoperatively for taking real-time informed decisions. We conducted a single institutional prospective study to identify the feasibility of ICG identification of vascularity of anastomotic site and its impact on the change of plan of surgical management in robotic rectal cancer surgery. Between September 2017 and April 2019, fifty patients undergoing robotic rectal cancer surgery were included in the study. The aim was to analyze the feasibility and clinical benefit of intraoperative near-infrared fluorescence imaging in determining the line of transection in comparison with the traditional method. Line of proximal transection of the bowel subjectively assessed by the surgical team was marked point B and that after ICG injection was marked point A if moved proximally and point C if moved distally. The vascular anatomy was clearly identified with no intraoperative or injection-related adverse effects. Of the 50 patients, the line of transaction remained the same in 6 patients (12%). Based on the fluorescence imaging, the surgical team opted for further proximal change of the transection line up to an "adequate" fluorescent portion in 3 patients (6%) and distally in 41 patients (82%). ICG-based infrared image-guided localization gives a real-time image of colon vascularity possibly affecting anastomotic leak. The ICG fluorescence imaging system is a simple, safe, and useful technique, performed within a short time, and it enables visual evaluation of the blood flow in the intestinal tract prior to anastomosis. Larger studies are needed before this can become the standard of care.

A trinity technique for prevention of low rectal anastomotic leakage in the robotic era

BACKGROUND

Anastomotic leakage (AL) is a severe complication of low anterior resection (LAR) for rectal cancer, and effective prevention is urgently needed. In the robotic era, this study aimed to explore the role of innovative techniques in preventing AL in rectal cancer patients undergoing robotic LAR.

METHODS

From May 2012 to May 2017, a total of 601 patients underwent robotic LAR, with 191 patients participated as control subjects (non-PST group) and 410 patients are subjected to a trinity technique (PST group). The AL rate, short-term and long-term outcomes are analyzed and compared.

RESULTS

The overall rate of AL was 6.8% out of 601 patients, with Grade B at 5.7% and Grade C at 1.1%, using the ISREC grading system. The PST group presented lower incidence of both overall AL (5.1% vs 10.5%, P = 0.015) and major AL (0.2% vs 3.2%, P = 0.005), when compared with the non-PST group, respectively. Furthermore, the PST group had similar surgical complications (17.3% vs 20.9%, P = 0.286), while with lower re-hospitalization rate (2.7% vs 6.3%, P = 0.038) and reoperation rate (0.2% vs 4.2%, P = 0.001), compared with the non-PST group, respectively. Short-term recovery and long-term oncological outcomes were not significant in the two groups. By multivariate logistic regression models, the risk factors of AL of robotic LAR are confirmed as non-PST technique, estimated blood loss ≥100 mL, anastomosis from anal verge <5 cm, and distal resection margin from tumor <2 cm.

CONCLUSIONS

The innovative PST technique may shed light on an effective method for preventing occurrence of AL in robotic LAR.

To what extent should the intestinal be resected proximally after radiotherapy: hint from a pathological view

BACKGROUND

Neoadjuvant chemoradiotherapy (nCRT) is associated with post-operative anastomotic complications in rectal-cancer patients. Anastomosis involving at least one non-irradiated margin reportedly significantly reduces the risk of post-operative anastomotic complications in radiation enteritis. However, the exact scope of radiotherapy on the remaining sigmoid colon remains unknown.

METHODS

We evaluated the radiation damage of proximally resected colorectal segments in 44 patients with rectal cancer, who received nCRT followed by conventional resection (nCRT-C, n = 21) or proximally extended resection (nCRT-E, n = 23). The segments from another 13 patients undergoing neoadjuvant chemotherapy (nCT) were used as control. We dissected these samples at a distance of 2 cm between the two adjacent sections. Radiation damage in proximally resected colorectal segments was evaluated using the radiation injury score (RIS) and the concentration and distribution patterns of angiostatin.

RESULTS

Compared to those in the nCT group, the nCRT group showed higher RIS, levels of angiostatin, and proportion of diffuse pattern of angiostatin. With increasing distance from the tumor site, these parameters all gradually decreased; and the differences came to be not significant at the site that is over 20 cm from the tumor. The nCRT-E group showed lower RIS (median: 2 vs 4, P = 0.002) and a greater proportion of non-diffuse angiostatin (87% vs 55%, P = 0.039) at the proximal margins compared with the nCRT-C group.

CONCLUSIONS

The severity of the radiation damage of the proximal colon is inversely proportional to the proximal-resection margin length. Little damage was left on the proximal margin that was over 20 cm from the tumor. Removal of an initial length of ≥20 cm from the tumor may be beneficial for rectal-cancer patients after nCRT.

A prospective study of real-time identification of line of transection in robotic colorectal cancer surgery by ICG

Colorectal cancer is the second most common cancer in women and the third most common cancer in men in the world. Surgical resection is the gold standard treatment and minimally invasive surgery remains the standard of care. Anastomotic leakage is one of the most feared postoperative complications in colorectal surgery. Although several factors have been identified as possible causes of anastomotic leakage (i.e., surgical techniques, patient risk factors, suture material or devices), the complete pathogenesis is still unclear. The reported leak rate ranges from 1 to 30% and increases as the anastomosis is more distal. To date the most widely used methods to assess tissue perfusion includes the surgeon intraoperative visual judgement based on the colour; bleeding edges of resected margins; pulsation and temperature, thereby resulting in either excess or insufficient colonic resection. Earlier studies in colorectal surgery have suggested that assessment of tissue perfusion by the clinical judgment of the operating surgeon underestimated the risk of anastomotic leakage. Indocyanine green (ICG) is a intravenous dye which has shown promise in identifying the bowel vascularity real time. Earlier studies on colorectal cancer have shown that ICG based detection of bowel vascularity is technically possible and has reduced the anastomotic leak rates in 16.7% of patients. We conducted a prospective study on patients with ICG guided bowel perfusion during robotic colorectal cancer surgery. The method is technically easy, reproducible and safe. This technique has changed the intraoperative decision in 88% of patients. Larger studies are needed before this can become the standard of care.

Indocyanine green fluorescence imaging to assess bowel perfusion during totally laparoscopic surgery for colon cancer

BACKGROUND

To retrospectively evaluate the feasibility and safety of intraoperative assessment of bowel perfusion in totally laparoscopic surgery for colon cancer using indocyanine green fluorescence imaging (IGFI).

METHODS

From October 2017 to June 2019, consecutive patients with colon cancer who underwent totally laparoscopic surgery were enrolled retrospectively and grouped into the IGFI group (n = 84) and control group (n = 105). In the IGFI group, indocyanine green (ICG) was injected intravenously, and the bowel perfusion was observed using a fluorescence camera system prior to and after completion of the anastomosis.

RESULTS

The two groups were demographically comparable. The IGFI group exhibited a significantly shorter operative time (p = 0.0374) while intraoperative blood loss did not significantly differ among the groups (p = 0.062). In the IGFI group, average time to perfusion fluorescence was 48.4 ± 14.0 s after ICG injection, and four patients (4.8%) were required to choose a more proximal point of resection due to the lack of adequate fluorescence at the point previously selected. There were no differences in terms of pathological outcomes, postoperative recovery and the postoperative complication rates between the groups (p>0.05).

CONCLUSION

IGFI shows promise as a safe and feasible tool to assess bowel perfusion during a totally laparoscopic surgery for colon cancer and may reduce the operative time.

Short-term and long-term outcomes of robotic rectal surgery-from the real word data of 1145 consecutive cases in China

Background

Due to a limited patient sample size, substantial data on robotic rectal resection (RRR) is lacking. Here, we reported a large consecutive cases from the real word data to assess the safety and efficacy of RRR.

Methods

From September 2010 to June 2017, a total of 1145 consecutive RRR procedures were performed in patients with stage I–IV disease. We conducted an analysis based on information from a prospectively designed database to evaluate surgical outcomes, urogenital function, and long-term oncological outcomes.

Results

Of three types of RRR performed, 227 (24.2%) were abdominoperineal resections, 865 (75.5%) were anterior resections, and 3 (0.3%) were Hartmann. Conversion to an open procedure occurred in 5.9% of patients. The overall positive circumferential margin rate was 1.3%. Surgical complication rate and mortality were 16.2% and 0.8% within 30 days of surgery, respectively. Mean hospital stay after surgery and hospital cost were 6.3 ± 2.9 days and 10442.5 ± 3321.5 US dollars, respectively. Risk factors for surgical complications included male gender, tumor location (mid-low rectum), combined organ resection, and clinical T category (cT3–4). Urinary function and general sexual satisfaction decreased significantly 1 month after surgery for both sexes. Subsequently, both parameters increased progressively, and the values 1 year after surgery were comparable to those measured before surgery. At a median follow-up of 34.6 months, local recurrence and distant metastases occurred in 2.3% and 21.1% of patients, respectively.

Conclusions

Robotic rectal resection was safe with preserved urogenital function and arrived equivalent oncological outcomes in a nonselected group of patients with rectal cancer.

Short-term efficacy of natural orifice specimen extraction surgery for low rectal cancer

BACKGROUND

This case-control study compared the short-term clinical efficacy of natural orifice specimen extraction surgery (NOSES) using a prolapsing technique and the conventional laparoscopic-assisted approach for low rectal cancer.

AIM

To further explore the application value of the transanal placement of the anvil and to evaluate the short-term efficacy of NOSES for resecting specimens of low rectal cancer, as well as to provide a theoretical basis for its extensive clinical application.

METHODS

From June 2015 to June 2018, 108 consecutive laparoscopic-assisted low rectal cancer resections were performed at our center. Among them, 26 specimens were resected transanally using a prolapsing technique (NOSES), and 82 specimens were resected through a conventional abdominal wall small incision (LAP). A propensity score matching method was used to select 26 pairs of matched patients, and their perioperative data were analyzed.

RESULTS

The baseline data were comparable between the two matched groups. All 52 patients underwent the surgery successfully. The operative time, blood loss, number of harvested lymph nodes, postoperative complication rate, circumferential margin involvement, postoperative follow-up data, and postoperative anal function were not statistically significant. The NOSES group had shorter time to gastrointestinal function recovery (2.6 ± 1.0 d vs 3.4 ± 0.9 d, P = 0.006), shorter postoperative hospital stay (7.1 ± 1.7 d vs 8.3 ± 1.1 d, P = 0.003), lower pain score (day 1: 2.7 ± 1.8 vs 4.6 ± 1.9, day 3: 2.0 ± 1.1 vs 4.1 ± 1.2, day 5: 1.7 ± 0.9 vs 3.3 ± 1.0, P < 0.001), a lower rate of additional analgesic use (11.5% vs 61.5%, P = 0.001), and a higher satisfaction rate in terms of the aesthetic appearance of the abdominal wall after surgery (100% vs 23.1%, P < 0.001).

CONCLUSION

NOSES for low rectal cancer can achieve satisfactory short-term efficacy and has advantages in reducing postoperative pain, shortening the length of postoperative hospital stay, and improving patients’ satisfaction in terms of a more aesthetic appearance of the abdominal wall.

Quantitative analysis of colon perfusion pattern using indocyanine green (ICG) angiography in laparoscopic colorectal surgery

Purpose

This study aimed to quantitatively evaluate colon perfusion patterns using indocyanine green (ICG) angiography to find the most reliable predictive factor of anastomotic complications after laparoscopic colorectal surgery.

Methods

Laparoscopic fluorescence imaging was applied to colorectal cancer patients (n = 86) from July 2015 to December 2017. ICG (0.25 mg/kg) was slowly injected into peripheral blood vessels, and the fluorescence intensity of colonic flow was measured sequentially, producing perfusion graphs using a video analysis and modeling tool. Colon perfusion patterns were categorized as either fast, moderate, or slow based on their fluorescence slope, T_1/2MAX and time ratio (TR = T_1/2MAX/T_MAX). Clinical factors and quantitative perfusion factors were analyzed to identify predictors for anastomotic complications.

Results

The mean age of patients was 65.4 years, and the male-to-female ratio was 63:23. Their operations were laparoscopic low anterior resection (55 cases) and anterior resection (31 cases). The incidence of anastomotic complication was 7%, including colonic necrosis (n = 1), anastomotic leak (n = 3), delayed pelvic abscess (n = 1), and delayed anastomotic dehiscence (n = 1). Based on quantitative analysis, the fluorescence slope, T_1/2MAX, and TR were related with anastomotic complications. The cut-off value of TR to categorize the perfusion pattern was determined to be 0.6, as shown by ROC curve analysis (AUC 0.929, P < 0.001). Slow perfusion (TR > 0.6) was independent factor for anastomotic complications in a logistic regression model (OR 130.84; 95% CI 6.45–2654.75; P = 0.002). Anastomotic complications were significantly correlated with the novel factor TR (> 0.6) as the most reliable predictor of perfusion and anastomotic complications.

Conclusions

Quantitative analysis of ICG perfusion patterns using T_1/2MAX and TR can be applied to detect segments with poor perfusion, thereby reducing anastomotic complications during laparoscopic colorectal surgery.

Complications of Diverting Ileostomy after Low Anterior Resection for Rectal Carcinoma

There have been few studies directly comparing the postoperative complications in patients with a diverting ileostomy to patients who were not diverted after low anterior resection (LAR) for rectal carcinoma. This study is a retrospective chart review of all rectal carcinoma patients (99) who underwent a LAR from January 2009 to December 2014 at Loma Linda University Medical Center and Veterans Affairs Loma Linda Healthcare System. A majority of patients were diverted (58% vs 42%). The diverted patients were more likely to have a low tumor location ( P < 0.01), preoperative chemoradiation ( P < 0.01), and more intraoperative blood loss ( P < 0.01). Our study shows a statistically significant higher overall complication rate among patients receiving a diverting ileostomy in the six months after LAR (61% vs 38%, P = 0.02). The difference is due to a higher rate of readmission (27% vs 14%) and acute kidney injury (14% vs 5%) in patients with a diverting ileostomy. It also shows that there is a higher rate of unplanned reoperation (11% vs 6%) due to anastomotic leak (17% vs 5%) in nondiverted patients. Further studies are needed to refine the specific indications to maximize the benefit of diverting ileostomy after LAR for rectal carcinoma.

Indocyanine green fluorescence angiography for intraoperative assessment of gastrointestinal anastomotic perfusion: a systematic review of clinical trials

PURPOSE

Anastomotic leakage following gastrointestinal surgery remains a frequent and serious complication associated with a high morbidity and mortality. Indocyanine green fluorescence angiography (ICG-FA) is a newly developed technique to measure perfusion intraoperatively. The aim of this paper was to systematically review the literature concerning ICG-FA to assess perfusion during the construction of a primary gastrointestinal anastomosis in order to predict anastomotic leakage.

METHODS

The following four databases PubMed, Scopus, Embase, and Cochrane were independently searched by two authors. Studies were included in the review if they assessed anastomotic perfusion intraoperatively with ICG-FA in order to predict anastomotic leakage in humans.

RESULTS

Of 790 screened papers 14 studies were included in this review. Ten studies (n = 916) involved patients with colorectal anastomoses and four studies (n = 214) patients with esophageal anastomoses. All the included studies were cohort studies. Intraoperative ICG-FA assessment of colorectal anastomoses was associated with a reduced risk of anastomotic leakage (n = 23/693; 3.3 % (95 % CI 1.97-4.63 %) compared with no ICG-FA assessment (n = 19/223; 8.5 %; 95 % CI 4.8-12.2 %). The anastomotic leakage rate in patients with esophageal anastomoses and intraoperative ICG-FA assessment was 14 % (n = 30/214). None of the studies involving esophageal anastomoses had a control group without ICG-FA assessment.

CONCLUSION

No randomized controlled trials have been published. ICG-FA seems like a promising method to assess perfusion at the site intended for anastomosis. However, we do not have the sufficient evidence to determine that the method can reduce the leak rate.

Indocyanine green-enhanced fluorescence to assess bowel perfusion during laparoscopic colorectal resection

Aims

Anastomotic leakage after colorectal surgery is a severe complication. One possible cause of anastomotic leakage is insufficient vascular supply. The aim of this study was to evaluate the feasibility and the usefulness of intraoperative assessment of vascular anastomotic perfusion in colorectal surgery using indocyanine green (ICG)-enhanced fluorescence.

Methods

Between May 2013 and October 2014, all anastomosis and resection margins in colorectal surgery were investigated using fluorescence angiography (KARL STORZ GmbH & Co. KG, Tuttlingen, Germany) intraoperatively to assess colonic perfusion prior to and after completion of the anastomosis, both in right and left colectomies.

Results

A total of 107 patients undergoing colorectal laparoscopic resections were enrolled: 40 right colectomies, 10 splenic flexure segmental resections, 35 left colectomies, and 22 anterior resections. In 90 % of cases, the indication for surgery was cancer and high ligation of vessels was performed. Based on the fluorescence intensity, the surgical team judged the distal part of the proximal bowel to be anastomosed insufficiently perfused in 4/107 patients (two anterior, one sigmoid and one segmental splenic flexure resections for cancer), and consequently, further proximal “re-resection” up to a “fluorescent” portion was performed. None of these patients had a clinical leak. The overall morbidity rate was 30 %; one patient undergoing right colectomy had an anastomotic leakage, apparently unrelated to ischemia; there were no clinical evident anastomotic leakages in colorectal resections including all low anterior resections.

Conclusions

ICG-enhanced fluorescent angiography provides useful intraoperative information about the vascular perfusion during colorectal surgery and may lead to change the site of resection and/or anastomosis, possibly affecting the anastomotic leak rate. Larger further randomized prospective trials are needed to validate this new technique.

National disparities in minimally invasive surgery for rectal cancer

BACKGROUND

Social and racial disparities have been identified as factors contributing to differences in access to care and oncologic outcomes in patients with colorectal cancer. The aim of this study was to investigate national disparities in minimally invasive surgery (MIS), both laparoscopic and robotic, across different racial, socioeconomic and geographic populations of patients with rectal cancer.

METHODS

We utilized the American College of Surgeons National Cancer Database to identify patients with rectal cancer from 2004 to 2011 who had undergone definitive surgical procedures through either an open, laparoscopic or robotic approach. Inclusion criteria included only one malignancy and no adjuvant therapy. Multivariate analysis was performed to investigate differences in age, gender, race, income, education, insurance coverage, geographic setting and hospital type in relation to the surgical approach.

RESULTS

A total of 8633 patients were identified. The initial surgical approach included 46.5% open (4016), 50.9% laparoscopic (4393) and 2.6% robotic (224). In evaluating type of insurance coverage, patients with private insurance were most likely to undergo laparoscopic surgery [OR (odds ratio) 1.637, 95% CI 1.178-2.275], although there was a less statistically significant association with robotic surgery (OR 2.167, 95% CI 0.663-7.087). Patients who had incomes greater than $46,000 and received treatment at an academic center were more likely to undergo MIS (either laparoscopic or robotic). Race, education and geographic setting were not statistically significant characteristics for surgical approach in patients with rectal cancer.

CONCLUSIONS

Minimally invasive approaches for rectal cancer comprise approximately 53% of surgical procedures in patients not treated with adjuvant therapy. Robotics is associated with patients who have higher incomes and private insurance and undergo surgery in academic centers.