Intraoperative colonoscopy in patients with colorectal cancer: Review of recent developments

Visualization of cecal tumor by near-infrared laparoscopy and intraoperative colonoscopy

BACKGROUND

In laparoscopic colorectal surgery, accurate localization of a tumor is essential for ensuring an adequate ablative margin. Therefore, a new method, near-infrared laparoscopy combined with intraoperative colonoscopy, was developed for visualizing the contour of a cecal tumor from outside of the bowel. The method was used after it was verified on a model that employed a silicone tube.

CASE PRESENTATION

The patient was a 77-year-old man with a cecal tumor near the appendiceal orifice. Laparoscopy was used to clamp of the terminal ileum, and a colonoscope was then inserted through the anus to the cecum. The laparoscope in the normal light mode could not be used to identify the cecal tumor. However, a laparoscope in the near-infrared ray mode could clearly visualize the contour of the cecal tumor from outside of the bowel, and the tumor could be safely resected by a stapler. The histopathological diagnosis of the resected specimen was adenocarcinoma with an invasion depth of M and a clear negative margin.

CONCLUSIONS

This is the first report of the laparoscopic detection of the contour of a cecal tumor from outside the bowel. This technique is useful and safe for contouring tumors in laparoscopic colorectal surgery and can be used in various surgeries that combine endoscopy and laparoscopy.

Effect of the lymphocyte-to-monocyte ratio on the prognosis of patients with obstructive colorectal cancer with a colonic stent: a retrospective multicenter study in Japan

PURPOSE

The prognostic value of the lymphocyte-to-monocyte (LMR) ratio has been reported for various cancers, including colorectal cancer (CRC). The insertion of colonic stents is considered effective for patients with surgically indicated obstructive CRC, but their LMR can vary depending on factors such as inflammation associated with stent dilation and improvement of obstructive colitis. However, the usefulness of the LMR in patients with obstructive CRC and colonic stents and the optimal timing for its measurement remain unclear. We conducted this study to investigate the relationship between the pre-stent LMR and the mid-term prognosis of patients with obstructive CRC and stents as a bridge to surgery (BTS).

METHODS

The subjects of this retrospective multicenter study were 175 patients with pathological stage 2 or 3 CRC. Patients were divided into a low pre-stent LMR group (n = 87) and a high pre-stent LMR group (n = 83).

RESULTS

Only 3-year relapse-free survival differed significantly between the low and high pre-stent LMR groups (39.9% vs. 63.6%, respectively; p = 0.015). The pre-stent LMR represented a prognostic factor for relapse-free survival in multivariate analyses (hazard ratio 2.052, 95% confidence interval 1.242-3.389; p = 0.005), but not for overall survival.

CONCLUSIONS

A low pre-stent LMR is a prognostic factor for postoperative recurrence in patients with obstructive CRC and a colonic stent as a BTS.

A comparison of the postoperative outcomes between intraoperative leak testing and no intraoperative leak testing for gastric cancer surgery: a systematic review and meta-analysis

BACKGROUND

Postoperative anastomotic leakage (PAL) is a serious complication of gastric cancer surgery. Although perioperative management has made considerable progress, anastomotic leakage (AL) cannot always be avoided. The purpose of this study is to evaluate whether intraoperative leak testing (IOLT) can reduce the incidence of PAL and other postoperative outcomes in gastric cancer surgery.

MATERIALS AND METHODS

In this meta-analysis, we searched the PubMed, Embase, and Cochrane Library databases for clinical trials to assess the application of IOLT in gastric cancer surgery. All patients underwent laparoscopic radical gastrectomy for gastric cancer surgery. Studies comparing the postoperative outcomes of IOLT and no intraoperative leak testing (NIOLT) were included. Quality assessment, heterogeneity, risk of bias, and the level of evidence of the included studies were evaluated. PAL, anastomotic-related complications, 30-day mortality, and reoperation rates were compared between the IOLT and NIOLT group.

RESULTS

Our literature search returned 721 results, from which six trials (a total of 1,666 patients) were included in our meta-analysis. Statistical heterogeneity was low. The primary outcome was PAL. IOLT reduced the incidence of PAL [2.09% vs 6.68%; (RR = 0.31, 95% Cl 0.19-0.53, P < 0.0001]. Anastomotic-related complications, which included bleeding, leakage, and stricture, were significantly higher in the NIOLT group than in the IOLT group [3.24% VS 10.85%; RR = 0.30, 95% Cl 0.18-0.53, P < 0.0001]. Moreover, IOLT was associated with lower reoperation rates [0.94% vs 6.83%; RR = 0.18, 95% CI 0.07-0.43, P = 0.0002].

CONCLUSION

Considering the observed lower incidence of postoperative anastomotic leakage (PAL), anastomotic-related complications, and reoperation rates, IOLT appears to be a promising option for gastric cancer surgery. It warrants further study before potential inclusion in future clinical guidelines.

Techniques for Diagnosing Anastomotic Leaks Intraoperatively in Colorectal Surgeries: A Review

Colorectal cancer is one of the most common surgically curable malignancies worldwide, having a good prognosis even with liver metastasis. This improved patient outcome is marred by anastomotic leaks (AL) in operated patients of colorectal cancer despite a microscopically margin-negative resection (R0). Various risk factors have been attributed to causing this. Preoperative non-modifiable factors are age, male sex, cancer cachexia, and neoadjuvant chemo-radiotherapy, and modifiable factors are comorbidities, peripheral vascular disease, anemia, and malnutrition. Intraoperative risk factors include intraoperative surgical duration, blood loss and transfusions, fluid management, oxygen saturation, surgical technique (stapled, handsewn, or compression devices), and approach (open, laparoscopic, or robotic). Postoperative factors like anemia, infection, fluid management, and blood transfusions also have an effect. With the advent of enhanced recovery after surgery (ERAS) protocols, many modifiable factors can be optimized to reduce the risk. Prevention is better than cure as the morbidity and mortality of AL are very high. There is still a need for an intraoperative technique to detect the viability of anastomotic ends to predict and prevent AL. Prompt diagnosis of an AL is the key. Many surgeons have proposed using methods like air leak tests, intraoperative endoscopy, Doppler ultrasound, and near-infrared fluorescence imaging to decrease the incidence of AL. All these methods can minimize AL, resulting in significant intraoperative alterations to surgical tactics. This narrative review covers the methods of assessing of integrity of anastomosis during the surgery, which can help prevent anastomotic leakage.

Detection methods of synchronous colorectal lesions in proximal colon for patients with obstructive colorectal cancer: a literature review

INTRODUCTION

Colorectal cancer holds a high morbidity and mortality rate. As a common method for colorectal cancer detection, colonoscopy has difficulty in passing through the malignant stenosis in patients with obstructive colorectal cancer, which results in incomplete detection and missed diagnosis. The missed synchronous lesions increase the risk of metachronous cancer. Therefore, detecting proximal synchronous lesions in patients with obstructive colorectal cancer should be appreciated before operation.

AREA COVERED

This review evaluates related literature, aiming at providing clinicians with more ideas and attention for detecting proximal synchronous lesions in patients with obstructive colorectal cancer.

EXPERT OPINION

In patients with obstructive colorectal cancer, missed diagnosis of lesions proximal to the obstruction may lead to metachronous colorectal cancer. Except for preoperative colonoscopy which is difficult to pass through malignant stenosis, other methods that can evaluate proximal colon segment are critical. This article introduced several preoperative, intraoperative and postoperative measures for synchronous lesions detection. The choice of methods should base on patients' conditions, aiming at a high diagnostic yield and low risk. Early detection and resection of synchronous lesions in the proximal section of malignant obstruction are expected to minimize the risk of metachronous colorectal cancer and even effect follow-up treatment strategy, which deserves the attention of clinicians.

Small-Dose Endoscopic Tattooing Using a Novel Needle for Localization Prior to Laparoscopic Surgery of Colorectal Cancer

BACKGROUNDS

Endoscopic tattooing failure by deep mural injection or tattoo leakage-induced massive staining causes localization errors or decreased laparoscopic visualization. To overcome these, we developed a novel tattoo needle with comparatively shorter needle (length, 2.5 mm) and minimal-caliber catheter (volume, 0.3 mL).

AIMS

The single-center, prospective observational study aimed to determine the efficacy and safety of a small-doze endoscopic tattooing prior to laparoscopic surgery for colorectal cancer, using the needle.

METHODS

Patients with colorectal cancer indicated for laparoscopic surgery were recruited. With the novel needle, a single tattoo was created at the anterior wall close to the lesion. During laparoscopic surgery, surgeons assessed the tattoo visibility, tattoo leakage, and the disturbance of laparoscopic view by tattoo leakage. The primary endpoint was an accurate localization by visible tattoo. Secondary endpoints were adverse events related to tattooing, the need for intraoperative endoscopy, and tattoo leakage.

RESULTS

A total of 383 tattoos in 358 patients were analyzed. Accurate tumor localization rate was 96.6% (95% confidence interval [CI]: 94.3-98.0%). No adverse events occurred. Intraoperative colonoscopy was performed in 7 (1.8%) patients with invisible tattoo. Tattoo leakage was found in 4.2% (95%CI: 2.6-6.7%), and leakage disturbed the laparoscopic view of the surgical plane in 0.7% (95%CI: 0.3-2.3%).

CONCLUSIONS

Prior to laparoscopic surgery for colorectal cancer, our endoscopic tattooing with a standardized protocol using a novel needle is considered a simple, highly reliable localization technique with an extremely safe profile, which would be valuable to reduce physician's efforts and redundant medical resources. Trial registration number UMIN000021012. Date of registration: June 2016.

Intra-operative assessment of left-sided colorectal anastomotic integrity: a systematic review of available techniques

AIM

Anastomotic leak (AL) after colorectal resection is associated with increased rates of morbidity and mortality: potential permanent stoma formation, increased local recurrence, reduced cancer-related survival, poor functional outcomes and associated quality of life. Techniques to reduce leak rates are therefore highly sought.

METHOD

A literature search was performed for published full text articles using PubMed, Cochrane and Scopus databases with a focus on colorectal surgery 1990-2020. Additional papers were detected by scanning references of relevant papers.

RESULTS

A total of 53 papers were included after a thorough literature search. Techniques assessed included leak tests, endoscopy, perfusion assessment and fluorescence studies. Air-leak testing remains the most commonly used method across Europe, due to ease of reproducibility and low cost. There is no evidence that this reduces the leak rate; however, identification of a leak intra-operatively provides the opportunity for either suture reinforcement or formal takedown with or without re-do of the anastomosis and consideration of diversion. Suture repair alone of a positive air-leak test is associated with an increased AL rate. The use of fluorescence studies to guide the site of anastomosis has demonstrated reduced leak rates in distal anastomoses, is safe, feasible and has a promising future.

CONCLUSION

Although over reliance on any assessment tool should be avoided, intra-operative techniques with the aim of reducing AL rates are increasingly being employed. Standardization of these methods is imperative for routine use. However, in the interim it is recommended that all anastomoses should be assessed intra-operatively for mechanical failure, particularly distal anastomoses.

Effectiveness and safety of tumor site marking with near-infrared fluorescent clips in colorectal laparoscopic surgery: A case series study

BACKGROUND

In colorectal laparoscopic surgery, accuracy of tumor marking has been an important but not fully resolved issue. The tattoo marking technique or intraoperative endoscopy have been used but they either carry the risk of accidental intestinal puncture or require either longer operation times, a skilled endoscopist and/or intraoperative colon insufflation. We supposed that tumor site marking with the near-infrared fluorescent clips, ZEOCLIP FS clips (Zeon Medical Co., Ltd., Tokyo, Japan) might overcome disadvantages of both tattoo marking and intraoperative endoscopy-based tumor localization methods. This is the first report on the case series using near-infrared fluorescent marking clip. We summarize the early results in 30 patients, who underwent colorectal laparoscopic surgery; we focus particularly on effectiveness and safety of the method.

MATERIALS AND METHODS

Thirty consecutive patients, who underwent laparoscopic surgery for colorectal cancer after previous endoscopic ZEOCLIP FS placement were enrolled from May 2019 till October 2019. The primary endpoint was the rate of intraoperative clip detection and the secondary endpoints were: the rate of adverse effects, percentage of slipped clips and usefulness of plain abdominal radiography to preoperatively confirm the clip retention. Locations of fluorescent clips were identified with a full-color fluorescence laparoscope. All operations and clip placements were performed by the same senior surgeon with sufficient experience in both procedures.

RESULTS

Fluorescent clips could be detected in 94.1% of tumor lesions. Three (2.1%) clips dropped before surgery. Plain abdominal radiography was sufficient to assess clip retention in all cases. No adverse effects related to either clip placement or clip detection were observed.

CONCLUSION

The ZEOCLIP FS could be easily detected from the serosal side of the intestinal tract when placed 1-2 days before surgery. Fluorescent clip-guided laparoscopy may be considered a safe and effective method for localization of colorectal tumor sites. The Research Registry UIN: researchregistry5400.

Anastomotic bleeding following ileocolic end-to-side anastomosis using a circular stapler: incidence and risk factors

PURPOSE

To identify the incidence of and risk factors for postoperative bleeding after ileocolic end-to-side anastomosis using a circular stapler.

METHODS

We analyzed, retrospectively, the risk factors for postoperative anastomotic bleeding in patients who underwent right-sided colectomy with end-to-side anastomosis done using a circular stapler during colon tumor surgery at our institute between January 2015 and March 2019.

RESULTS

Anastomotic bleeding developed in 10 (3.6%) of the total 279 patients. Univariate analysis revealed that age ≥ 80 years (8.8% vs. 1.9%; P = 0.008) and Eastern Cooperative Oncology Group performance status (ECOG PS) ≥ 1 (12.5% vs. 2.8%; P = 0.014) were significant risk factors for anastomotic bleeding. Postoperative anticoagulation therapy was not a risk factor for anastomotic bleeding. Multivariate analysis revealed that only age ≥ 80 years was an independent risk factor (odds ratio 4.12, 95% confidence interval 1.02-16.68, P = 0.047). Six of the ten patients with anastomotic bleeding were treated conservatively, three were treated by colonoscopic clipping, and one required surgery.

CONCLUSION

End-to-side anastomosis is safe and feasible, but must be performed carefully in the elderly, who are at higher risk of anastomotic bleeding.

Accurate localization of rectal cancer using near infrared ray-guided surgery with intra-operative colonoscopy and da Vinci Firefly technology

Accurate localization of the tumor during robot-assisted laparoscopic surgery for rectal cancer is crucial. Several techniques have been described, but each has its shortcomings. We developed a new technique of near infrared ray-guided surgery (NIRGS) to localize the tumor accurately, using intra-operative colonoscopy and da Vinci Firefly technology. After clamping the oral side of the tumor, the colonoscope was inserted. In the normal visible light mode, we could not recognize the endoscopic light; however, after changing to the Firefly mode, the endoscopic light was seen clearly. Using this simple and new technique, we could locate the tumor easily and accurately. We performed this technique in 12 patients and detected the location of the tumor clearly in all, without any procedure-related complications. Based on these findings, NIRGS is a useful and safe technique for detecting tumor location during robot-assisted laparoscopic surgery for rectal cancer.

Use of laparoscopic equipment for colonoscopy intraoperatively in case of lack of colonoscope

In the case where intraoperative endoscopy is necessary and there is no endoscope available in the hospital, there is a solution, the use of available laparoscopic equipment. The technique is simple and without being time consuming. All its needed is a laparoscopic video- camera, and laparoscopic ports. The whole procedure takes place in the surgical field and provides an immediate solution for the endoscopic inspection of stomach, small intestine and large intestine. We describe the first case where it takes place in an open right colectomy in a patient with colon cancer and a suspicious lesion at the left colon. Further studies are needed to evaluate the indications and the effectiveness of the method.

The Role of Bowel Preparation in Open, Minimally Invasive, and Converted-to-Open Colectomy

BACKGROUND

Bowel preparation before colectomy is considered an effective strategy to decrease postoperative complications. However, data regarding the effect of bowel preparation in patients undergoing minimally invasive colectomy are limited. The aim of this study was to investigate the role of different bowel preparation strategies in patients undergoing open, minimally invasive, and converted-to-open elective colectomies.

METHODS

We identified 39,355 patients who underwent elective colectomy from the American College of Surgeons National Surgical Quality Improvement Program colectomy-targeted database (2012-2016). Multivariate logistic regression models were used to assess the impact of different bowel preparation strategies on postoperative complications and mortality in three subapproach groups: open (n = 12,141), minimally invasive (n = 23,057), and converted to open (n = 4157).

RESULTS

Overall, a total of 10,066 (25.6%) patients received no preparation (NP), 11,646 (29.5%) mechanical bowel preparation (MBP) alone, 1664 (4.2%) antibiotic bowel preparation (ABP) alone, and 15,979 (40.6%) MBP + ABP. Compared with NP, MBP + ABP showed the strongest protective effects. MBP + ABP was associated with reduced risk of major complications (odds ratio [OR] = 0.60, 95% confidence interval [CI]: 0.55-0.66), infectious complications (OR = 0.50, 95% CI: 0.46-0.54), any complications (OR = 0.55, 95% CI: 0.51-0.60), 30-d mortality (OR = 0.68, 95% CI: 0.48-0.96), anastomotic leak (OR = 0.50, 95% CI: 0.43-0.58), and length of stay ≥ 4 d (OR = 0.64, 95% CI: 0.61-0.67) in overall population. These protective effects, except for 30-d mortality, were observed in open, minimally invasive, and converted-to-open groups. When the analysis was limited to robotic surgery only, MBP + ABP was only associated with reduced risk of major complications (OR = 0.61, 95% CI: 0.38-0.97) compared with NP. The protective effects remained similar over the study time period.

CONCLUSIONS

MBP + ABP is a preferred preoperative strategy in open, minimally invasive, and converted-to-open colectomy.

Efficacy of 18-fluoro deoxy glucose-positron emission tomography computed tomography for the detection of colonic neoplasia proximal to obstructing colorectal cancer

Identification of secondary colonic neoplasia proximal to obstructing colorectal cancer is essential for determining the range of colorectal resection.We examined the accuracy of 18-fluoro deoxy glucose-positron emission tomography (FDG-PET) for detection of colonic neoplasia.We recruited patients with obstructing colorectal cancer from our registry. Preoperative FDG-PET was performed, and the detection rate for colonic neoplasia was estimated. Preoperative colonoscopy or postoperative colonoscopy within a year after operation was employed as the indexed standard.Ninety-three patients were included in this study. Colonic neoplasia proximal to obstruction was confirmed in 83 cases. The sensitivity and positive predictive value of FDG-PET were 25.3% and 77.8%, respectively. The sensitivity was higher in larger lesions (3.2% for <5 mm, 29.4% for 6-10 mm, 45.5% for 11-20 mm, and 71.4% for >21 mm) and in higher pathological grade lesions (14.6% for low-grade adenoma, 38.5% for high-grade adenoma, 66.7% for carcinoma in situ, and 100% for invasive carcinoma). The round shape in PET images was a predictor for neoplasia, with an area under the curve of 0.75293 at an aspect ratio of 1.70.FDG-PET should be used as a screening modality for invasive colorectal cancer (CRC) proximal to obstructing colorectal cancer.

Contribution of intraoperative colonoscopy in a colorectal surgery unit. Scand J Gastroenterol 2017;52:1292-1297. [PMID: 28768440 DOI: 10.1080/00365521.2017.1362465]

OBJECTIVES

Intraoperative colonoscopy (IC) is routinely used in colorectal surgery procedures, both oncologic and benign ones. Despite its extensive use there is a lack of literature addressing this important issue. The aims of this paper are to determine the contributions of this tool, especially considering changes in attitude from preoperative designed intervention.

MATERIALS AND METHODS

This study is a retrospective analysis of a prospective maintained database. Patients who underwent colorectal resection and IC during a four-year period (2009-2012). The indications for performing IC in our unit are: Incomplete preoperative colonoscopy, confirm the exact location of the tumor and polypectomy of any lesion distant from the planned resection segment.

RESULTS

The success rate in performing IC is 100%, including 42% of them made trans-anastomotic. No postoperative complications that were attributable to the endoscopy were detected. Routine practice led to a change in attitude in 5% of the patients analyzed; 2% of the global sample corresponded to synchronous tumors finding. Of those patients in whom polypectomies where achieved during the procedure a 14.3% of potentially malignant lesions were resected.

CONCLUSIONS

Intraoperative colonoscopy is a useful and safe tool that in view of these results should be taken into account at any colorectal surgery unit. Trans-anastomotic techniques do not raise morbidity.

Intraoperative colonoscopy for the assessment and prevention of anastomotic leakage in low anterior resection for rectal cancer

PURPOSE

Anastomotic leakage (AL) after stapled anastomosis in rectal cancer surgery is a major concern. Various types of intraoperative anastomotic air leakage tests (ALTs) have been proposed to reduce AL. This study aimed to evaluate the impact of intraoperative colonoscopy (IOC) as an intraoperative ALT in low anterior resection for rectal cancer.

METHODS

A total of 1266 patients were retrospectively reviewed. Among them, 215 patients who underwent IOC as an ALT in rectal cancer surgery were identified. IOC was performed after anastomosis to visualize the anastomosis line and to perform an ALT by insufflating the neorectum. Propensity score matching was used to match this group at a 1:1 ratio with 215 patients who underwent ALT with a 250-mL bulb irrigation syringe. Anastomotic defects that were found intraoperatively were resolved either by means of primary repair of the anastomotic defect, if possible, or by performing a preventive diverting ileostomy.

RESULTS

The patient characteristics, pathologic outcomes, and operation details showed no significant difference between the two groups. Comparison of the AL rate showed a significant difference between the groups (IOC group without intraoperative leaks vs. non-IOC group without intraoperative leaks 4.3 vs. 11.7%, P = 0.007). The incidence of preventive diverting ileostomy because of a positive ALT was significantly higher in the IOC group than in the non-IOC group (10 vs. 2 cases, P = 0.036).

CONCLUSION

IOC can be a valuable method for the assessment of stapled anastomosis and has the additional benefit of directly visualizing the anastomosis line.