Efficacy of Assessing Intraoperative Bowel Perfusion with Near-Infrared Camera in Laparoscopic Gastric Cancer Surgery

Fluorescence and tracers in surgery: the coming future

The revolution that we are seeing in the world of surgery will determine the way we understand surgical approaches in coming years. Since the implementation of minimally invasive surgery, innovations have constantly been developed to allow the laparoscopic approach to go further and be applied to more and more procedures. In recent years, we have been in the middle of another revolutionary era, with robotic surgery, the application of artificial intelligence and image-guided surgery. The latter includes 3D reconstructions for surgical planning, virtual reality, holograms or tracer-guided surgery, where ICG-guided fluorescence has provided a different perspective on surgery. ICG has been used to identify anatomical structures, assess tissue perfusion, and identify tumors or tumor lymphatic drainage. But the most important thing is that this technology has come hand in hand with the potential to develop other types of tracers that will facilitate the identification of tumor cells and ureters, as well as different light beams to identify anatomical structures. These will lead to other types of systems to assess tissue perfusion without the use of tracers, such as hyperspectral imaging. Combined with the upcoming introduction of ICG quantification, these developments represent a real revolution in the surgical world. With the imminent implementation of these technological advances, a review of their clinical application in general surgery is timely, and this review serves that aim.

[Fluorescence navigation and angiography with indocyanine green in stomach cancer surgery]

OBJECTIVE

To evaluate the effectiveness of intraoperative angiography and fluorescence navigation with indocyanine green in reducing the risks of intra- and postoperative complications, as well as resection quality in patients with gastric cancer.

MATERIAL AND METHODS

The main group consisted of patients who underwent intraoperative angiography and fluorescence navigation with indocyanine green (n=43). The control group included patients without these procedures (n=154). Both groups did not differ in gender (p=0.937) and age (p=0.437). The lower third of the stomach was the most common tumor location in the main group (62.7% of cases), the middle and lower thirds of the stomach - in the control group (37% and 38.9% of patients, respectively). There was no between-group difference in «cT» grading (p>0.05). However, there were more «cN+» patients in the main group (14 (32.6%) versus 28 (18.4%) ones of «N0» category, p=0.042). Therefore, 41.9% and 13.6% of patients underwent neoadjuvant chemotherapy in both groups, respectively (<0.001).

RESULTS

Intraoperative angiography and fluorescence navigation with indocyanine green does not increase mortality (p=0.631), incidence of major (CD 3-5) (p=0.436) and minor (CD 1-2) postoperative complications (p=0.177), surgery time (p=0.288), mean intraoperative blood loss (p=0.144) and length of hospital-stay (p=0.631). Fluorescence navigation with indocyanine green does not affect the number of detected «positive» resection margins (R1) (p=0.883) but significantly increases the number of excised lymph nodes (p<0.001).

CONCLUSION

Intraoperative angiography and fluorescence navigation with indocyanine green are safe for intraoperative visualization of tumor and lymph nodes, as well as assessment of arterial blood supply. This technique is effective in traditional and minimally invasive surgeries for gastric cancer. Fluorescence navigation with indocyanine green significantly increases the number of excised lymph nodes.

Progress of near-infrared-II fluorescence in precision diagnosis and treatment of colorectal cancer

Colorectal cancer is a malignant tumour with high incidence and mortality worldwide; therefore, improving the early diagnosis of colorectal cancer and implementing a targeted "individualized treatment" strategy is of great concern. NIR-II fluorescence imaging is a large-depth, high-resolution optical bioimaging tool. Around the NIR-II window, researchers have developed a variety of luminescent probes, imaging systems, and treatment methods with colorectal cancer targeting capabilities, which can be visualized and image-guided in clinical surgery. This article aims to overcome the difficulties in diagnosing and treating colorectal cancer. The present review summarizes the latest results on using NIR-II fluorescence for targeted colorectal cancer imaging, expounds on the application prospects of NIR-II optical imaging for colorectal cancer, and discusses the imaging-guided multifunctional diagnosis and treatment platforms.

Impact of anastomotic leakage on survival after surgery for gastric carcinoma: A PRISMA systematic review and meta-analysis

BACKGROUND

The long-term survival of postoperative anastomotic leakage (AL) following gastric cancer (GC) surgery is still debating. Our aim was to investigate the association between AL and survival of the patients following GC.

METHODS

We searched articles in databases from inception to July 2023 to retrieve literature related to postoperative AL and survival of GC patients. We evaluated the association of postoperative AL and survival of GC patients using the software STAT10.0.

RESULTS

Seven articles with 6209 GC patients were included. Our results showed that the postoperative AL were associated with pooled 1-year patient overall survival (OS) result in an odds ratio (OR) of 0.504 (95% confidence interval (CI): 0.372-0.682; I2 = 84.1%; P = .000), pooled 3-year patient OS (OR = 0.467, 95% CI: 0.356-0.614; I2 = 85.3%; P = .000) and pooled 5-year patient OS (OR = 0.370, 95% CI: 0.171-0.805; I2 = 82.5%; P = .012). The P value of Egger test were 0.759, 0.187, 0.175. The postoperative AL were associated with pooled 1-year patient disease-free survival (DFS) result in an OR of 0.538 (95% CI: 0.171-1.691; I2 = 89.0%; P = .289), the pooled 3-year patient DFS (OR = 0.143, 95% CI: 0.119-1.431; I2 = 91.7%; P = .163), and the pooled 5-year patient DFS (OR = 0.344, 95% CI: 0.088-1.338; I2 = 91.0%; P = .124), and the P value of Egger test of pooled 1-, 3-, and 5-year DFS were 0.759, 0.247, 0.07.

CONCLUSION

Postoperative AL was correlated with a worse OS in GC patients, but not correlated with DFS in GC patients, but more studies are required to confirm this conclusion.

Application of near-infrared fluorescence imaging in theranostics of gastrointestinal tumors

Gastrointestinal cancers have become an important cause of cancer-related death in humans. Improving the early diagnosis rate of gastrointestinal tumors and improving the effect of surgical treatment can significantly improve the survival rate of patients. The conventional diagnostic method is high-definition white-light endoscopy, which often leads to missed diagnosis. For surgical treatment, intraoperative tumor localization and post-operative anastomotic state evaluation play important roles in the effect of surgical treatment. As a new imaging method, near-infrared fluorescence imaging (NIRFI) has its unique advantages in the diagnosis and auxiliary surgical treatment of gastrointestinal tumors due to its high sensitivity and the ability to image deep tissues. In this review, we focus on the latest advances of NIRFI technology applied in early diagnosis of gastrointestinal tumors, identification of tumor margins, identification of lymph nodes, and assessment of anastomotic leakage. In addition, we summarize the advances of NIRFI systems such as macro imaging and micro imaging systems, and also clearly describe the application process of NIRFI from system to clinical application, and look into the prospect of NIRFI applied in the theranostics of gastrointestinal tumors.

Effect of indocyanine green near-infrared light imaging technique guided lymph node dissection on short-term clinical efficacy of minimally invasive radical gastric cancer surgery: a meta-analysis

Objective

In recent years, the utilization of indocyanine green near-infrared (ICG NIR) light imaging-guided lymph node dissection in the context of minimally invasive radical gastric cancer has emerged as a novel avenue for investigation. The objective of this study was to assess the influence of employing this technique for guiding lymph node dissection on the short-term clinical outcomes of minimally invasive radical gastric cancer surgery.

Methods

The present study conducted a comprehensive search for short-term clinical outcomes, comparing the group undergoing ICG NIR light imaging-guided lymph node dissection with the control group, by thoroughly examining relevant literature from the inception to July 2023 in renowned databases such as PubMed, Embase, Web of Science, and Cochrane Library. The primary endpoints encompassed postoperative complications, including abdominal infection, abdominal bleeding, pneumonia, anastomotic fistula, and overall incidence of complications (defined as any morbidity categorized as Clavien-Dindo class I or higher within 30 days post-surgery or during hospitalization). Additionally, secondary outcome measures consisted of the time interval until the initiation of postoperative gas and food intake, as well as various other parameters, namely postoperative hospital stay, operative time, intraoperative blood loss, total number of harvested lymph nodes, and the number of harvested metastatic lymph nodes. To ensure methodological rigor, the Cochrane Collaboration Risk of Bias Tool and the Newcastle-Ottawa Scale (NOS) were employed to assess the quality of the included studies, while statistical analyses were performed using Review Manager 5.4 software and Stata, version 12.0 software.

Results

A total of 19 studies including 3103 patients were ultimately included (n=1276 in the ICG group and n=1827 in the non-ICG group). In this meta-analysis, the application of ICG near-infrared light imaging in minimally invasive radical gastric cancer surgery effectively improved the occurrence of postoperative Clavien-Dindo grade II or higher complications in patients (RR=0.72, 95% CI 0.52 to 1.00) with a statistically significant P=0.05; in reducing intraoperative blood loss and shortening While reducing intraoperative blood loss and shortening postoperative hospital stay, it could ensure the thoroughness of lymph node dissection in minimally invasive radical gastric cancer surgery (MD=5.575, 95% CI 3.677-7.473) with significant effect size (Z=5.76, p<0.00001).

Conclusion

The utilization of indocyanine green near-infrared light imaging technology in the context of minimally invasive radical gastric cancer surgery demonstrates notable efficacy in mitigating the occurrence of postoperative complications surpassing Clavien-Dindo grade II, while concurrently augmenting both the overall quantity of lymph node dissections and the identification of positive lymph nodes, all the while ensuring the preservation of surgical safety. Furthermore, the implementation of this technique proves particularly advantageous in the realm of robotic-assisted radical gastric cancer surgery, thus bearing significance for enhancing the short-term prognostic outcomes of patients.

Indocyanine green (ICG) fluorescence guide for the use and indications in general surgery: recommendations based on the descriptive review of the literature and the analysis of experience

Indocyanine Green is a fluorescent substance visible in near-infrared light. It is useful for the identification of anatomical structures (biliary tract, ureters, parathyroid, thoracic duct), the tissues vascularization (anastomosis in colorectal, esophageal, gastric, bariatric surgery, for plasties and flaps in abdominal wall surgery, liver resection, in strangulated hernias and in intestinal ischemia), for tumor identification (liver, pancreas, adrenal glands, implants of peritoneal carcinomatosis, retroperitoneal tumors and lymphomas) and sentinel node identification and lymphatic mapping in malignant tumors (stomach, breast, colon, rectum, esophagus and skin cancer). The evidence is very encouraging, although standardization of its use and randomized studies with higher number of patients are required to obtain definitive conclusions on its use in general surgery. The aim of this literature review is to provide a guide for the use of ICG fluorescence in general surgery procedures.

Modified -shaped esophagojejunostomy in totally laparoscopic total gastrectomy: a report of 40 consecutive cases from a single center

Objective

Intracorporeal esophagojejunostomy remains a challenging technique in totally laparoscopic total gastrectomy (TLTG) because of the lack of an established standard anastomosis method. However, π-shaped esophagojejunostomy in TLTG is reportedly safe and feasible. Therefore, we evaluated the short-term surgical outcomes of our modified π-shaped esophagojejunostomy in TLTG.

Methods

This study involved patients without neoadjuvant therapy diagnosed with gastric cancer who underwent TLTG by the same surgeon with modified π-shaped esophagojejunostomy from April 2018 to October 2019. Clinicopathologic data were collected and retrospectively analyzed.

Results

Forty patients diagnosed with gastric cancer were included. The mean operative time and estimated blood loss were 264.6 ± 56.9 minutes and 68.5 ± 53.3 mL, respectively. Postoperative flatus occurred at 4.6 ± 1.7 days. The mean time to resumption of diet was 7.4 ± 1.7 days postoperatively. One patient was diagnosed with anastomotic leakage and managed with conservative therapy. Pleural effusion was the most common complication, occurring in four (10%) patients. One patient developed intra-abdominal bleeding that required reoperation. Other complications were atrial fibrillation and wound infection. No mortality occurred during the 6-month follow-up.

Conclusions

Modified π-shaped esophagojejunostomy is safe and feasible for intracorporeal anastomosis in TLTG and showed favorable surgical outcomes in this study.

The Use of Indocyanine Green (ICG) and Near-Infrared (NIR) Fluorescence-Guided Imaging in Gastric Cancer Surgery: A Narrative Review

Near-infrared fluorescence imaging with indocyanine green is an emerging technology gaining clinical relevance in the field of oncosurgery. In recent decades, it has also been applied in gastric cancer surgery, spreading among surgeons thanks to the diffusion of minimally invasive approaches and the related development of new optic tools. Its most relevant uses in gastric cancer surgery are sentinel node navigation surgery, lymph node mapping during lymphadenectomy, assessment of vascular anatomy, and assessment of anastomotic perfusion. There is still debate regarding the most effective application, but with relatively no collateral effects and without compromising the operative time, indocyanine green fluorescence imaging carved out a role for itself in gastric resections. This review aims to summarize the current indications and evidence for the use of this tool, including the relevant practical details such as dosages and times of administration.

Association between Vascular Calcification and Esophagojejunal Anastomotic Complications after Total Gastrectomy for Gastric Cancer: A Propensity-Matched Study

Esophagojejunal anastomosis (EJA) complications after total gastrectomy are related to significant morbidity and mortality. The aim of this study was to evaluate the association between arterial calcifications and EJA complications such as leak and stricture for gastric cancer. Between January 2014 and October 2019, 30 patients with EJA complications after total gastrectomy were enrolled and matched to 30 patients without complications through retrospective data review. Arterial calcification grade on preoperative computed tomography (CT) was reported in the abdominal aorta and superior mesenteric artery (SMA) as “absent”, “minor”, or “major”, and in the jejunal vascular arcade (JVA) and left inferior phrenic artery (LIPA) as “absent” or “present”. A Chi-square test was used to compare the variables between the two groups. p-Value < 0.050 was considered statistically significant. Among 30 patients, the numbers of patients with leak and stricture were 23 and seven, respectively. Aortic calcifications were not associated with EJA complications regardless of their grade (p = 0.440). Only major SMA calcifications were associated with EJA complications, as they were present in five patients (16.7%) in the complication group and absent in the non-complication group (p = 0.020). Major SMA calcifications were more related to anastomotic stricture than leak. Three (13.0%) out of 23 patients with leak and two (28.6%) out of seven with stricture had major SMA calcifications (p = 0.028). No calcifications were detected in the JVA or LIPA in any of the 60 patients. Major SMA calcifications were found to be associated with EJA complications, especially in stricture.

Modern surgical therapy for gastric cancer-Robotics and beyond

The surgical paradigm for gastric cancer has been changed from extended surgery to minimally invasive surgery. Laparoscopic surgery is a practical method for minimally invasive surgery for early gastric cancer, and the indication is expanding to advanced gastric cancer. In recent years, robotic gastrectomy has been highlighted as a breakthrough to overcome the drawbacks of laparoscopic gastrectomy. Here, we discuss the recent updates of modern surgical therapy for gastric cancer-robotics and beyond.

Near-Infrared Fluorescence Image-Guided Surgery in Esophageal and Gastric Cancer Operations

Background

Near-infrared fluorescence image-guided surgery helps surgeons to see beyond the classical eye vision. Over the last few years, we have witnessed a revolution which has begun in the field of image-guided surgery.

Purpose, and Research design

Fluorescence technology using indocyanine green (ICG) has shown promising results in many organs, and in this review article, we wanted to discuss the 6 main domains where fluorescence image-guided surgery is currently used for esophageal and gastric cancer surgery.

Study sample and data collection

Visualization of lymphatic vessels, tumor localization, fluorescence angiography for anastomotic evaluation, thoracic duct visualization, tracheal blood flow analysis, and sentinel node biopsy are discussed.

Conclusions

It seems that this technology has already found its place in surgery. However, new possibilities and research avenues in this area will probably make it even more important in the near future.

Impact of the indocyanine green fluorescence method for anastomotic blood flow in robotic distal gastrectomy

PURPOSE

To evaluate the blood flow at the site of delta-shaped anastomosis during robotic distal gastrectomy and determine surgical outcomes and risk factors for ischemia at the anastomotic site from the perspective of clinical characteristics, surgical outcomes and perigastric vascular anatomy.

METHODS

We included 55 patients who underwent robotic distal gastrectomy with a blood flow evaluation in the duodenal walls using intravenous indocyanine green injection with the da Vinci Xi-equipped Firefly system. Additional resection was performed in patients with a poor blood flow. Clinical characteristics, surgical outcomes and perigastric vascular anatomy were compared between the 45 patients with sufficient blood flow (group S) and the 10 patients with insufficient blood flow (group I). Vascular anatomy was assessed by preoperative contrast-enhanced computed tomography according to Hiatt's classification.

RESULTS

The patient characteristics and surgical outcomes were not significantly different. No patient developed anastomotic complications requiring intervention; more patients in group I had aberrant branching of the left hepatic artery than those in group S (p = 0.047).

CONCLUSIONS

An indocyanine green-based blood flow evaluation might be an effective method of preventing anastomotic complications of delta-shaped anastomosis. Anatomical branching variations of the left hepatic artery might be a risk factor for impaired vascular perfusion of the anastomotic site.

New Intraoperative Imaging Tools and Image-Guided Surgery in Gastric Cancer Surgery

Innovations and new advancements in intraoperative real-time imaging have gained significant importance in the field of gastric cancer surgery in the recent past. Currently, the most promising procedures include indocyanine green fluorescence imaging (ICG-FI) and hyperspectral imaging or multispectral imaging (HSI, MSI). ICG-FI is utilized in a broad range of clinical applications, e.g., assessment of perfusion or lymphatic drainage, and additional implementations are currently investigated. HSI is still in the experimental phase and its value and clinical relevance require further evaluation, but initial studies have shown a successful application in perfusion assessment, and prospects concerning non-invasive tissue and tumor classification are promising. The application of machine learning and artificial intelligence technologies might enable an automatic evaluation of the acquired image data in the future. Both methods facilitate the accurate visualization of tissue characteristics that are initially indistinguishable for the human eye. By aiding surgeons in optimizing the surgical procedure, image-guided surgery can contribute to the oncologic safety and reduction of complications in gastric cancer surgery and recent advances hold promise for the application of HSI in intraoperative tissue diagnostics.

Current Status and Trends of Minimally Invasive Gastrectomy in Korea

Since its introduction in the early 1990s, laparoscopic gastrectomy has been widely accepted for the treatment of gastric cancer worldwide. In the last decade, the Korean Laparoendoscopic Gastrointestinal Surgery Study group performed important clinical trials and exerted various efforts to enhance the quality of scientific knowledge and surgical techniques in the field of gastric cancer surgery. Laparoscopic gastrectomy has shifted to a new era in Korea due to recent advances and innovations in technology. Here, we discuss the recent updates of laparoscopic gastrectomy—namely, reduced-port, single-incision, robotic, image-guided, and oncometabolic surgery.

Safety and efficacy of indocyanine green fluorescence imaging-guided radical gastrectomy: a systematic review and meta-analysis

BACKGROUND

The clinical value of indocyanine green (ICG) in laparoscopic radical gastrectomy remains controversial. We performed this meta-analysis to investigate the safety and efficacy of ICG fluorescence imaging-guided radical gastrectomy.

METHODS

All relevant studies published until 30 October 2020 were retrieved from several databases. Fixed- and random-effects models were used to analyze the results based on different heterogeneity levels. Data were expressed as odds ratios or weighted mean differences along with 95% confidence intervals. The Grading of Recommendations, Assessment, Development, and Evaluation system scale was used for quality of evidence evaluation.

RESULTS

This meta-analysis included six cohort studies that investigated 622 patients. Compared with conventional radical gastrectomy, ICG fluorescence imaging-guided gastrectomy facilitates complete lymph node dissection, reduces intraoperative blood loss, and shortens the length of postoperative hospitalization. Moreover, we observed no significant intergroup differences in the operative time, first exhaust time, and postoperative complications.

CONCLUSION

ICG fluorescence imaging-guided radical gastrectomy scores over conventional gastrectomy and appears to be a promising approach in patients who require radical gastrectomy. However, further research is warranted to explore the potential long-term survival benefit of ICG fluorescence imaging in patients with gastric cancer.

The short-term and long-term outcomes of indocyanine green tracer-guided laparoscopic radical gastrectomy in patients with gastric cancer

Background

The safety and efficacy of indocyanine green (ICG) imaging navigational laparoscopic gastrectomy remain controversial. This study is to evaluate the short-term and long-term outcomes of ICG-guided laparoscopic radial gastrectomy in patients with gastric cancer.

Methods

Consecutive patients with definitive diagnosis of gastric cancer that underwent laparoscopic radical gastrectomy were collected retrospectively. Propensity score matching (PSM) at 1:1 ratio was performed to compare the outcomes of two groups.

Results

A total of 122 qualified patients were divided into ICG group (n = 34) and non-ICG group (n = 88). PSM yielded 28 patients with comparable baseline characteristics into each group. The number of retrieved lymph node in ICG group was significantly higher than that in non-ICG group (P = 0.0196). There was no statistical difference of perioperative, short-term, and long-term complications between the two groups.

Conclusion

ICG-guided laparoscopic radical gastrectomy is safe and effective, and ICG-navigated lymphadenectomy improves the number of retrieved lymph nodes for patients with gastric cancer.

Evaluation of Near-infrared Fluorescence-conjugated Peptides for Visualization of Human Epidermal Receptor 2-overexpressed Gastric Cancer

Purpose

A near-infrared (NIR) fluorescence imaging is a promising tool for cancer-specific image guided surgery. Human epidermal receptor 2 (HER2) is one of the candidate markers for gastric cancer. In this study, we aimed to synthesize HER2-specific NIR fluorescence probes and evaluate their applicability in cancer-specific image-guided surgeries using an animal model.

Materials and Methods

An NIR dye emitting light at 800 nm (IRDye800CW; Li-COR) was conjugated to trastuzumab and an HER2-specific affibody using a click mechanism. HER2 affinity was assessed using surface plasmon resonance. Gastric cancer cell lines (NCI-N87 and SNU-601) were subcutaneously implanted into female BALB/c nu (6–8 weeks old) mice. After intravenous injection of the probes, biodistribution and fluorescence signal intensity were measured using Lumina II (Perkin Elmer) and a laparoscopic NIR camera (InTheSmart).

Results

Trastuzumab-IRDye800CW exhibited high affinity for HER2 (K_D=2.093(3) pM). Fluorescence signals in the liver and spleen were the highest at 24 hours post injection, while the signal in HER2-positive tumor cells increased until 72 hours, as assessed using the Lumina II system. The signal corresponding to the tumor was visually identified and clearly differentiated from the liver after 72 hours using a laparoscopic NIR camera. Affibody-IRDye800CW also exhibited high affinity for HER2 (K_D=4.71 nM); however, the signal was not identified in the tumor, probably owing to rapid renal clearance.

Conclusions

Trastuzumab-IRDye800CW may be used as a potential NIR probe that can be injected 2–3 days before surgery to obtain high HER2-specific signal and contrast. Affibody-based NIR probes may require modifications to enhance mobilization to the tumor site.

Value of preoperative gastroscopic carbon nanoparticles labeling in patients undergoing laparoscopic radical gastric cancer surgery

BACKGROUND AND OBJECTIVES

Lymph node metastasis is crucial for gastric cancer. We aim to explore the value of preoperative gastroscopic carbon nanoparticles labeling in patients undergoing laparoscopic radical gastric cancer surgery.

METHODS

1199 cases undergoing laparoscopic radical gastric cancer surgery were retrospectively analyzed. 214 cases received preoperative gastroscopic carbon nanoparticles labeling. The number of total lymph nodes detected, positive lymph nodes, N staging, and operation time were analyzed.

RESULTS

The patients received carbon nanoparticles labeling had more total lymph nodes detected (27.9 ± 6.5 vs 22.2 ± 4.0; P ＜ 0.001) and shorter operation time (185.9 ± 27.8min vs 218.7 ± 69.2min; P ＜ 0.001) compared with the control group. In addition, preoperative endoscopic carbon nanoparticles labeling improved the diagnosis rate of synchronous multiple gastric cancer (2.8% vs 0.4%; P ＜ 0.001).

CONCLUSIONS

Preoperative endoscopic carbon nanoparticles tracer labeling is of great value in patients undergoing laparoscopic radical gastric cancer surgery. It shortens the operation time, increases the number of total lymph nodes detected for more accurate pathological TNM staging, and finds some cases of synchronous multiple gastric cancer.

Defining indocyanine green fluorescence to assess anastomotic perfusion during gastrointestinal surgery: systematic review

Background

The aim of this systematic review was to identify all methods to quantify intraoperative fluorescence angiography (FA) of the gastrointestinal anastomosis, and to find potential thresholds to predict patient outcomes, including anastomotic leakage and necrosis.

Methods

This systematic review adhered to the PRISMA guidelines. A PubMed and Embase literature search was performed. Articles were included when FA with indocyanine green was performed to assess gastrointestinal perfusion in human or animals, and the fluorescence signal was analysed using quantitative parameters. A parameter was defined as quantitative when a diagnostic numeral threshold for patient outcomes could potentially be produced.

Results

Some 1317 articles were identified, of which 23 were included. Fourteen studies were done in patients and nine in animals. Eight studies applied FA during upper and 15 during lower gastrointestinal surgery. The quantitative parameters were divided into four categories: time to fluorescence (20 studies); contrast‐to‐background ratio (3); pixel intensity (2); and numeric classification score (2). The first category was subdivided into manually assessed time (7 studies) and software‐derived fluorescence–time curves (13). Cut‐off values were derived for manually assessed time (speed in gastric conduit wall) and derivatives of the fluorescence–time curves (F_max, T_1/2, TR and slope) to predict patient outcomes.

Conclusion

Time to fluorescence seems the most promising category for quantitation of FA. Future research might focus on fluorescence–time curves, as many different parameters can be derived and the fluorescence intensity can be bypassed. However, consensus on study set‐up, calibration of fluorescence imaging systems, and validation of software programs is mandatory to allow future data comparison.

[Status of minimally invasive gastrectomy : Current advancements: robotic surgery and intraoperative imaging for gastric cancer]

The surgical treatment of gastric cancer has arrived at a turning point towards the routine application of minimally invasive techniques. After the first results of prospective randomized trials from Asia confirmed the surgical and oncological safety, the latest results of international trials provided evidence for minimally invasive gastrectomy of advanced gastric cancer in a multimodal setting. A new addition in the field of minimally invasive procedures is robotic-assisted surgical techniques, which have already been implemented for these indications in many centers in Germany. The technical advantages that are applicable in the robotics setting in comparison to laparoscopy lead to a rapid dissemination of the procedure but still need to be evaluated in controlled trials. Further developments for the surgical treatment of gastric cancer are found in the field of intraoperative imaging procedures. In this field various technologies are available, such as fluorescence imaging using a near-infrared camera, which requires the use of a fluorescent agent or the hyperspectral camera system, which does not require the application of a fluorophore and merges pictures from visible and non-visible wavelengths to a functional image. It is to be expected that in the future various technological advancements can make a valuable contribution to the surgical treatment of gastric cancer in the clinical routine, especially if they support and facilitate the use of minimally invasive surgical techniques.

Jejunal limb obstruction by a tumor thrombus from pancreatic metastasis of renal cell carcinoma: a case report

BACKGROUND

Renal cell carcinoma (RCC) is a primary tumor with the highest frequency of pancreatic metastasis. Although surgical resection can improve the prognosis of some patients with pancreatic metastasis of RCC (PM-RCC), the role of palliative surgery remains unclear. Herein, we described a case of jejunal limb occlusion caused by a tumor thrombus arising from a PM-RCC which was treated by surgical resection.

CASE PRESENTATION

A 75-year-old, male patient with metastatic RCC was admitted to our hospital with new-onset dysphagia and weight loss. Twenty years earlier he underwent a right nephrectomy with an adrenalectomy for the first surgical resection of RCC, and 12 years ago he underwent a left partial nephrectomy for metachronous primary RCC. Nine years later, multiple pancreatic metastases were detected. After discontinuing interferon therapy, he was followed up at his request without anticancer treatment. Multiple, pulmonary metastases developed 3 years ago, and resection of a brain metastasis was performed 6 months ago. He had also undergone a total gastrectomy with Roux-en Y reconstruction and splenectomy for gastric cancer 23 years ago. Computed tomography revealed a metastatic lesion in the pancreatic tail extending into the jejunal limb, which was obstructed by a tumor thrombus. Jejunal limb resection was performed concomitantly with a distal pancreatectomy as palliative surgery. The jejunal limb remnant was approximately 30 cm long and was re-anastomosed to the esophagus using a circular stapler. Blood perfusion at the anastomotic site was confirmed by indocyanine green fluorescence imaging. He was discharged on postoperative day 24 and was followed in the outpatient clinic. He achieved sufficient oral intake at 8 months postoperatively.

CONCLUSIONS

PM-RCC can invade the gastrointestinal tract and cause tumor thrombus formation resulting in bowel occlusion requiring surgical intervention.

A Novel Parameter Identified Using Indocyanine Green Fluorescence Angiography may Contribute to Predicting Anastomotic Leakage in Gastric Cancer Surgery

BACKGROUND

Anastomotic leak is one of the most serious postoperative complications, and intraoperative adequate perfusion plays a key role in preventing its development in gastric cancer surgery. This study aimed to investigate the relationships between anastomotic leak and the parameters defined by an assessment of intraoperative anastomotic perfusion using a near-infrared indocyanine green (ICG) fluorescence system and to evaluate the usefulness of this ICG fluorescence assessment in gastric cancer surgery.

METHODS

We retrospectively reviewed data of 100 patients who underwent gastric cancer surgery. In a visual assessment based on fluorescence intensity, we classified ICG fluorescence image patterns as homogeneous, heterogeneous, or faint. In a chronological assessment, the first or second time point of ICG fluorescence appearance on one or the other side of the anastomosis was defined as FT or ST, respectively. The time difference in ICG fluorescence appearance between FT and ST was defined as TD. The relationships between anastomotic leak and the evaluated clinical factors, including the parameters identified by the ICG fluorescence assessment, were evaluated using univariate or multivariate analysis.

RESULTS

Although no signs of leak were found by surgeons' subjective judgments, four patients developed postoperative anastomotic leak of Clavien-Dindo grade III or IV. Multivariate analysis revealed that TD was an independent predictor of anastomotic leak (odds ratio 35.361, 95% confidence interval 1.489-839.923, p = 0.027).

CONCLUSIONS

A novel parameter identified using near-infrared ICG fluorescence assessment may be useful to predict anastomotic leak in gastric cancer surgery.

TRIAL REGISTRATION

UMIN Clinical Trials Registry: #UMIN000030747 ( https://www.umin.ac.jp/ctr/index.htm ).

Real-time identification of aberrant left hepatic arterial territories using near-infrared fluorescence with indocyanine green during gastrectomy for gastric cancer

BACKGROUND

An aberrant left hepatic artery is frequently encountered during upper gastrointestinal surgery, and researchers have yet to propose optimal strategies with which to address this arterial variation. The objective of this study was to determine whether the areas perfused by an aberrant left hepatic artery can be visualized in real-time using near-infrared fluorescence imaging with indocyanine green.

METHODS

Patients with gastric adenocarcinoma who underwent minimally invasive radical gastrectomy from May 2018 to August 2019 were enrolled and retrospectively analyzed at a single-center. Patients with an aberrant left hepatic artery and normal preoperative liver function were examined. After the clamping of an aberrant left hepatic artery, indocyanine green was administered via a peripheral intravenous route during surgery. Fluorescence at the liver was visualized under near-infrared fluorescence imaging.

RESULTS

In 31 patients with aberrant left hepatic arteries, near-infrared fluorescence imaging was used without adverse events associated with indocyanine green. Six (19%) patients were reported to have an aberrant left hepatic artery upon preoperative CT imaging, while all other instances were detected during surgery. Fluorescence excitation on the liver was, on average, visible after 43 s (range, 25-65). Fluorescence across the entire surface of the liver was noted in 20 (65%) patients in whom the aberrant left hepatic artery could be ligated. Aberrant left hepatic arteries were safely preserved in 10 (32%) patients who showed areas of no or partial fluorescence excitation. Guided by near-infrared fluorescence imaging, ligation of aberrant left hepatic arteries elicited no significant changes in postoperative liver function.

CONCLUSION

Near-infrared fluorescence imaging facilitates the identification of aberrant left hepatic arterial territories, guiding decisions on the preservation or ligation of this arterial variation.

Safety and Efficacy of Indocyanine Green Tracer-Guided Lymph Node Dissection During Laparoscopic Radical Gastrectomy in Patients With Gastric Cancer: A Randomized Clinical Trial

Importance

The application of indocyanine green (ICG) imaging in laparoscopic radical gastrectomy is in the preliminary stages of clinical practice, and its safety and efficacy remain controversial.

Objective

To investigate the safety and efficacy of ICG near-infrared tracer-guided imaging during laparoscopic D2 lymphadenectomy in patients with gastric cancer.

Design, Setting, and Participants

Patients with potentially resectable gastric adenocarcinoma (clinical tumor stage cT1-cT4a, N0/+, M0) were enrolled in a prospective randomized clinical trial at a tertiary referral teaching hospital between November 2018 and July 2019. Patients were randomly assigned to the ICG group or the non-ICG group. The number of retrieved lymph nodes, rate of lymph node noncompliance, and postoperative recovery data were compared between the groups in a modified intention-to-treat analysis. Statistical analysis was performed from August to September 2019.

Interventions

The ICG group underwent laparoscopic gastrectomy using near-infrared imaging after receiving an endoscopic peritumoral injection of ICG to the submucosa 1 day before surgery.

Main Outcomes and Measures

Total number of retrieved lymph nodes.

Results

Of 266 participants randomized, 133 underwent ICG tracer-guided laparoscopic gastrectomy, and 133 underwent conventional laparoscopic gastrectomy. After postsurgical exclusions, 258 patients were included in the modified intention-to-treat analysis, which comprised 129 patients (86 men and 43 women; mean [SD] age, 57.8 [10.7] years) in the ICG group and 129 patients (87 men and 42 women; mean [SD] age, 60.1 [9.1] years) in the non-ICG group. The mean number of lymph nodes retrieved in the ICG group was significantly more than the mean number retrieved in the non-ICG group (mean [SD], 50.5 [15.9] lymph nodes vs 42.0 [10.3] lymph nodes, respectively; P < .001). Significantly more perigastric and extraperigastric lymph nodes were retrieved in the ICG group than in the non-ICG group. In addition, the mean total number of lymph nodes retrieved in the ICG group within the scope of D2 lymphadenectomy was also significantly greater than the mean number retrieved in the non-ICG group (mean [SD], 49.6 [15.0] lymph nodes vs 41.7 [10.2] lymph nodes, respectively; P < .001). The lymph node noncompliance rate of the ICG group (41 of 129 patients [31.8%]) was lower than that of the non-ICG group (74 of 129 patients [57.4%]; P < .001). The postoperative recovery process was comparable, and no significant difference was found between the ICG and non-ICG groups in the incidence (20 of 129 patients [15.5%] vs 21 of 129 [16.3%], respectively; P = .86) or severity of complications within 30 days after surgery.

Conclusions and Relevance

Indocyanine green can noticeably improve the number of lymph node dissections and reduce lymph node noncompliance without increased complications in patients undergoing D2 lymphadenectomy. Indocyanine green fluorescence imaging can be performed for routine lymphatic mapping during laparoscopic gastrectomy, especially total gastrectomy.

Trial Registration

ClinicalTrials.gov Identifier: NCT03050879.

Incidence and risk factors for fluorescence abnormalities on near-infrared imaging using indocyanine green in stapled functional end-to-end anastomosis in laparoscopic colectomy

PURPOSE

Recently, several studies have suggested that near-infrared (NIR) imaging using indocyanine green (ICG) may contribute to the reduction of anastomotic leakage (AL) after colorectal cancer (CRC) surgery. However, few reports have focused on the usefulness of NIR imaging for AL after stapled functional end-to-end anastomosis (stapled FEEA). The purpose of this study was to clarify the frequency of fluorescence abnormalities on NIR imaging, in cases reconstructed with stapled FEEA.

METHODS

This retrospective study included patients with colon or appendiceal cancer who underwent laparoscopic colectomy with stapled FEEA reconstruction between March 2016 and August 2019.

RESULTS

A total of 400 patients who were managed at our three institutions were included in the present study. The rate of Clavien-Dindo (CD) grade > III AL was 1.0% (4/400). The median length of postoperative hospital stay was 7 days (IQR 25-75th percentile 6-8 days). In 11 patients (2.8%), the transection line was changed by NIR imaging, due to fluorescence abnormalities. The rate of transverse colon involvement in anastomosis was significantly higher in cases with fluorescence abnormalities than in cases with normal fluorescence (p = 0.035).

CONCLUSIONS

The frequency of fluorescence abnormalities on NIR was 2.8% in cases of colon resection with reconstruction by using stapled FEEA. There was a probability of abnormal fluorescence on NIR in cases where the transverse colon was involved in the anastomosis. This means that NIR may have potential benefit in such cases.

TRIAL REGISTRATION

UMIN000039977.

Advances in laparoscopic surgery for the treatment of advanced gastric cancer in China

Most gastric cancer (GC) cases are diagnosed at an advanced stage in China. Because of its high morbidity and mortality, GC remains a major health crisis in China. Surgical resection is the only potentially curative treatment for GC. Owing to being minimally invasive, laparoscopic radical gastrectomy has been widely used in various countries, especially in East Asia, since Kitano first reported the feasibility and safety of this technique. Although laparoscopic gastric surgery was introduced relatively late in China, Chinese surgeons have made unique contributions to the research and clinical practice of laparoscopic gastric surgery due to the large number of clinical cases. This review focuses on the progress in laparoscopic gastrectomy for advanced stage GC in China, including reasonable approaches in different areas and oncologic efficacy of laparoscopic surgery, and introduce advanced technology to facilitate surgeons to rapidly overcome the learning curve in clinical practice.

Successful preservation of the proximal stomach tube by evaluating blood flow using indocyanine green for gastric tube cancer: a case report

BACKGROUND

There have been two reports on preserving the proximal gastric tube by using intraoperative indocyanine green (ICG)-based photodynamic detection to evaluate blood flow through the anastomosis for gastric tube cancer after esophagectomy. However, in those cases, the period since the first operation was > 3 years 11 months, and there have been no reports of cases with < 1-year periods after the first operation.

CASE PRESENTATION

A 59-year-old man underwent video-assisted thoracic subtotal esophagectomy and gastric tube reconstruction after two courses of preoperative chemotherapy for middle thoracic esophageal cancer. After half a year, follow-up upper gastrointestinal endoscopy showed a submucosal tumor in the posterior wall of the pre-pyloric region. We performed a biopsy, and the results led to a diagnosis of gastric cancer (moderately differentiated adenocarcinoma: tub2). Clinically, the patient was described as having stage IB (cT2N0M0) gastric cancer of the reconstructed gastric tube. To avoid total gastrectomy, we tried to evaluate the blood flow of the proximal part of the gastric tube by intraoperative ICG-based photodynamic detection. Intraoperative findings confirmed neo-vascularization from the remnant cervical esophagus to the upper region of the gastric tube approximately 7 cm through the esophagogastric anastomosis. Therefore, we dissected the distal part of the gastric tube approximately 4 cm from the esophagogastric anastomosis and then performed Roux-en-Y gastro-jejunostomy via the ante-sternum route. The postoperative course was stable, and the patient was discharged on the 14th postoperative day.

CONCLUSIONS

ICG-based photodynamic diagnosis was found to be simple and less invasive. Therefore, even if the postoperative period is short, this method should be considered for evaluation of blood flow prior to performing less invasive surgery.

Global updates in the treatment of gastric cancer: a systematic review. Part 2: perioperative management, multimodal therapies, new technologies, standardization of the surgical treatment and educational aspects

Gastric cancer is the fifth malignancy and the third cause of cancer death worldwide, according to the global cancer statistics presented in 2018. Its definition and staging have been revised in the eight edition of the AJCC/TNM classification, which took effect in 2018. Novel molecular classifications for GC have been recently established and the process of translating these classifications into clinical practice is ongoing. The cornerstone of GC treatment is surgical, in a context of multimodal therapy. Surgical treatment is being standardized, and is evolving according to new anatomical concepts and to the recent technological developments. This is leading to a massive improvement in the use of mini-invasive techniques. Mini-invasive techniques aim to be equivalent to open surgery from an oncologic point of view, with better short-term outcomes. The persecution of better short-term outcomes also includes the optimization of the perioperative management, which is being implemented on large scale according to the enhanced recovery after surgery principles. In the era of precision medicine, multimodal treatment is also evolving. The long-time-awaited results of many trials investigating the role for preoperative and postoperative management have been published, changing the clinical practice. Novel investigations focused both on traditional chemotherapeutic regimens and targeted therapies are currently ongoing. Modern platforms increase the possibility for further standardization of the different treatments, promote the use of big data and open new possibilities for surgical learning. This systematic review in two parts assesses all the current updates in GC treatment.

Near-infrared fluorescence-guided surgery using indocyanine green facilitates secure infrapyloric lymph node dissection during laparoscopic distal gastrectomy

PURPOSE

We aimed to investigate the usefulness of near-infrared indocyanine green (ICG)-enhanced fluorescence guidance for infrapyloric LN dissection in laparoscopic distal gastrectomy.

METHODS

This study enrolled patients with early gastric cancer scheduled for laparoscopic distal gastrectomy. After intraoperative submucosal injection of ICG (0.1 mg/mL), LN dissection was conducted under near-infrared ICG fluorescence guidance. The operation time, bleeding events during infrapyloric LN dissection were analyzed. Cases were retrospectively 1:3 propensity-score matched to patients who underwent laparoscopic distal gastrectomy without ICG injection.

RESULTS

The mean time from midline omentectomy to exposure of the right gastroepiploic vein was significantly shorter in the ICG group (n = 20) than in the non-ICG group (n = 60) (13.05 ± 5.77 vs 18.68 ± 7.92 min; p = 0.001), and the incidence of bleeding during infrapyloric LN dissection was lower in the ICG group (20% vs 68.3%, p < 0.001). The two groups did not differ significantly regarding the number of LNs retrieved from the infrapyloric area (p = 0.434).

CONCLUSIONS

Near-infrared ICG fluorescence guidance facilitates safe and fast infrapyloric LN dissection in laparoscopic distal gastrectomy.