Fluorescence-guided lymphadenectomy in gastric cancer: a prospective western series

The use of indocyanine green and near-infrared fluorescence in the detection of metastatic lymph nodes during oesophageal and gastric cancer resection: a systematic review and meta-analysis

BACKGROUND

Lymph node status is one of the most important prognosticating factors for patients afflicted by oesophageal cancer (OC) and gastric cancer (GC), and lymphadenectomy during surgery is therefore an essential step to ensure complete oncological resection and accurate disease staging. Intraoperative lymph node visualisation using near-infrared fluorescence (NIRF) and indocyanine green (ICG) tracing has been postulated to improve the overall lymph node yield, and to ensure the appropriate radicality, but its usefulness in the detection of metastatic lymph nodes remains unclear.

METHODS

We conducted a systematic review and meta-analysis of the relevant literature to ascertain the accuracy of ICG-guided lymphadenectomy in the detection of metastatic nodes in OC and GC. The primary outcomes were the sensitivity, specificity and diagnostic odds ratio of ICG-guided lymphadenectomy. Secondary outcomes included measurement of the effect of prior neoadjuvant chemotherapy (NAC), tumour characteristics and method of ICG administration. Summary receiver operator characteristic (SROC) curves were built to illustrate the relationship between the sensitivity of ICG and false positive rate.

RESULTS

From an initial search of 6,302 articles, 15 studies met the criteria for inclusion, incorporating 4,004 patients. The pooled sensitivity for metastatic node detection was 69.1% (95% CI 56.5-79.3%), specificity 47.4% (38.0-56.9%), and DOR 2.02 (1.40-2.92). The SROC curve for diagnostic test accuracy yielded an area under the curve of 0.60. The use of NAC adversely affected the sensitivity of ICG 74.7% [59.2-85.8%] without NAC; 52.8% [43.6-61.9%] with NAC, p = 0.018). No significant difference in efficacy was demonstrated between pathological 'T' stage, or ICG administration method.

CONCLUSION

Our findings suggest that the oncological benefits of NIRF and ICG in the context of lymphadenectomy in OC and GC are limited, and that surgeons risk omitting a significant proportion of metastatic nodes if this technique is solely relied upon.

Evaluating Variations in Indocyanine Green Administration and Its Impact on Nodal Yield in Oesophagogastric Cancer Surgery

BACKGROUND

Indocyanine green (ICG), a near-infrared fluorescent dye, has the potential to improve oncological outcomes by increasing lymph node yield in oesophagogastric (OG) cancer. There is no consensus regarding the dose, timing, and method of injection. This study was designed to evaluate the variation in ICG administration and its potential impact on nodal yield in OG cancer surgery for the purpose of translation in Western patients.

METHODS

A systematic review and meta-analysis were conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) guidelines. The primary outcome of this review was nodal yield, and the secondary outcome was the diagnostic accuracy of ICG in detecting metastatic lymph nodes. A meta-analysis of diagnostic accuracy data was performed by using a random-effects model.

RESULTS

A total of 38 studies (12,138 patients) were included in the analysis. Nodal yield was significantly increased in the ICG groups by 7.6 nodes (95% confidence interval [CI] 5.9-9.4; P = 0.0001) compared with control. Trends towards greater nodal yield were observed when ICG was administered at doses less than 2.75 mg, on the day before surgery, and via subserosal injection, although these did not reach statistical significance. Of the 17 studies with diagnostic accuracy data, the pooled sensitivity and specificity of ICG were 0.81 (95% CI 0.67-0.90) and 0.41 (95% CI 0.29-0.53), I2 90.5%.

CONCLUSIONS

Indocyanine green-assisted lymphadenectomy significantly increased lymph node yield, which may translate into improved survival in patients with OG cancer. The ICG dose, timing, and method of injection warrant standardisation to maximise its potential benefits in Western patients.

Comparison of a submucosal and subserosal approach in ICG-guided laparoscopic lymphadenectomy in gastric cancer patients: long-term outcomes of a phase 3 randomized clinical trial

BACKGROUND

Previous studies have demonstrated similar short-term efficacy between subserosal (SSA) and submucosal (SMA) approaches for ICG injection in gastric cancer (GC). This study aims to compare the long-term oncological outcomes of these two injection methods for lymph node (LN) tracing in ICG-guided laparoscopic gastrectomy.

MATERIALS AND METHODS

This study was a phase 3, open-label, randomized clinical trial (FUGES-019). A total of 266 patients with resectable gastric adenocarcinoma (cT1-4a, N0/ +, M0) were enrolled. We report predefined long-term secondary outcomes, including three-year actual overall survival (OS), three-year actual disease-free survival (DFS), and recurrence patterns.

RESULTS

Of the 266 participants, 259 patients were included in the per-protocol analysis: 129 in the SSA group and 130 in the SMA group. The actual OS in the SSA group (87.6%) was comparable to that in the SMA group (90.8%, P = 0.41), as were the 3-year actual DFS rates (SSA: 82.9% vs. SMA: 88.5%, log-rank P = 0.19). Per-protocol analysis confirmed the equivalence of the SSA compared with the SMA. The most common type of recurrence was multiple site metastasis (11 of 259[4.24%]), with no differences in recurrence types across cancer stages. Further stratified analysis based on pT, pN staging, tumor size, and BMI showed no significant differences between the two groups.

CONCLUSION

The 3-year outcomes of the FUGES-019 trial confirm the equivalence of SSA and SMA in ICG-guided laparoscopic lymphadenectomy for GC, supporting the previous short-term findings. The subserosal approach can be recommended for ICG administration based on clinical considerations.

Evaluating the Role of Robotic Surgery Gastric Cancer Treatment: A Comprehensive Review by the Robotic Global Surgical Society (TROGSS) and European Federation International Society for Digestive Surgery (EFISDS) Joint Working Group

INTRODUCTION

Robot-assisted minimally invasive gastrectomy (RAMIG) represents a significant advancement in the surgical management of gastric cancer, offering superior dexterity, enhanced visualization, and improved ergonomics compared to laparoscopic gastrectomy (LG). This review systematically evaluates the current evidence on perioperative outcomes, oncological efficacy, learning curves, and economic considerations, providing insights into RAMIG's potential role in modern gastric cancer surgery.

METHODS

A thorough analysis of retrospective, prospective, and meta-analytic studies was conducted to compare RAMIG with LG. Key outcomes, including operative time, intraoperative blood loss, lymph node retrieval, postoperative complications, learning curve duration, and cost-effectiveness, were assessed. Emphasis was placed on both short-term and long-term oncological outcomes to determine the clinical value of RAMIG.

RESULTS

Evidence indicates that RAMIG is associated with reduced intraoperative blood loss, lower morbidity rates, and a shorter learning curve, with proficiency achieved after 11-25 cases compared to 40-60 cases for LG. The robotic platform's articulated instruments and enhanced three-dimensional visualization enable more precise lymphadenectomy, particularly in complex anatomical regions. Despite these advantages, operative time remains longer, and costs remain higher due to system acquisition, maintenance, and consumable expenses. However, emerging data suggest a gradual narrowing of cost disparities. While short-term outcomes are favorable, further high-quality, multicenter studies are needed to validate long-term oncological efficacy and survival outcomes.

CONCLUSION

RAMIG offers significant technical and clinical advantages over conventional LG, particularly in terms of precision and learning efficiency. However, the long-term oncological benefits and economic feasibility require further validation. Future research should focus on cost optimization, advanced technological integration such as near-infrared fluorescence and artificial intelligence, and multicenter trials to solidify RAMIG's role as a standard approach for 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.

Superior lymph node harvest by fluorescent lymphography during minimally invasive gastrectomy for gastric cancer patients with high body mass index

BACKGROUND

Fluorescent lymphography (FL) using indocyanine green (ICG) allows for the visualization of all draining lymph nodes (LNs), thereby increasing LN retrieval. However, no studies have assessed the efficacy of FL in high body mass index (BMI) gastric cancer patients, even as LN yield decreases with increasing BMI in gastrectomy. This study aimed to investigate the influence of FL on LN retrieval in high BMI gastric cancer patients.

METHODS

Gastric cancer patients who underwent laparoscopic or robotic gastrectomies from 2013 to 2021 were included. Patients were classified into two groups, with FL (FL group) or without FL (non-FL group). The effect of FL on LN retrieval was assessed by BMI. Inverse probability of treatment weighting (IPTW) was used to ensure comparability between groups.

RESULTS

Retrieved LN number decreased as BMI increased regardless of FL application (P < 0.001). According to the IPTW analysis, the mean retrieved LN number was significantly higher in the FL group (48.4 ± 18.5) than in the non-FL group (39.8 ± 16.3, P < 0.001), irrespective of BMI. The FL group exhibited a significantly higher proportion of patients with 16 or more LNs (99.5%) than the non-FL group (98.1%, P < 0.001). The FL group also had a significantly higher proportion of patients with 30 or more LNs (86.6%) than the non-FL group (72.2%, P < 0.001). In both the normal and high-BMI patients, the FL group had a significantly larger percentage of patients with a higher nodal classification than the non-FL group.

CONCLUSION

FL resulted in more LN retrieval, even in high BMI patients. FL ensures accurate staging by maintaining the appropriate retrieved LN number in high BMI gastric cancer patients.

History and evidence for state of the art of lymphadenectomy in esophageal cancer surgery

The current curative multimodal treatment of advanced esophageal cancers consists of neoadjuvant or perioperative chemo(radio)therapy followed by a radical surgical resection of the primary tumor and a 2- or 3-field lymphadenectomy. One of the most important predictors of long-term survival of esophageal cancer patients is lymph node involvement. The distribution pattern of lymph node metastases in esophageal cancer is unpredictable and depends on the primary tumor location, histology, T-stage and application of neoadjuvant or perioperative treatment. The optimal extent of the lymphadenectomy remains controversial; there is no global consensus on this topic yet. Some surgeons advocate an aggressive and extended lymph node dissection to remove occult metastatic disease, to optimize oncological outcomes. Others promote a more restricted lymphadenectomy, since the benefit of an extended lymphadenectomy, especially after neoadjuvant chemoradiotherapy, has not been clearly demonstrated, and morbidity may be reduced. In this review, we describe the development of lymphadenectomy, followed by a summary of current evidence for lymphadenectomy in esophageal cancer treatment.

Indocyanine green: The guide to safer and more effective surgery

In this editorial we comment on the article by Kalayarasan and co-workers published in the recent issue of the World Journal of Gastrointestinal Surgery. The authors present an interesting review on the use of indocyanine green fluorescence in different aspects of abdominal surgery. They also highlight future perspectives of the use of indocyanine green in mini-invasive surgery. Indocyanine green, used for fluorescence imaging, has been approved by the Food and Drug Administration and is safe for use in humans. It can be administered intravenously or intra-arterially. Since its advent, there have been several advancements in the applications of indocyanine green, especially in the surgical field, such as intraoperative mapping and biopsy of sentinel lymph node, measurement of hepatic function prior to resection, in neurosurgical cases to detect vascular anomalies, in cardiovascular cases for patency and assessment of vascular abnormalities, in predicting healing following amputations, in helping visualization of hepatobiliary anatomy and blood vessels, in reconstructive surgery, to assess flap viability and for the evaluation of tissue perfusion following major trauma and burns. For these reasons, the intraoperative use of indocyanine green has become common in a variety of surgical specialties and transplant surgery. Colorectal surgery has just lately begun to adopt this technique, particularly for perfusion visualization to prevent anastomotic leakage. The regular use of indocyanine green coupled with fluorescence angiography has recently been proposed as a feasible tool to help improve patient outcomes. Using the best available data, it has been shown that routine use of indocyanine green in colorectal surgery reduces the rates of anastomotic leak. The use of indocyanine green is proven to be safe, feasible, and effective in both elective and emergency scenarios. However, additional robust evidence from larger-scale, high-quality studies is essential before incorporating indocyanine green guided surgery into standard practice.

Impact of tumor stage and neoadjuvant chemotherapy in fluorescence-guided lymphadenectomy during laparoscopic gastrectomy for gastric cancer: A propensity score-matched study in a western center

BACKGROUND

The use of indocyanine green fluorescence has been shown to be a safe and effective method for improving lymph node retrieval in patients with gastric cancer. However, previous studies have focused on early-stage tumors and/or the Asian population and excluded patients who received neoadjuvant treatment.

METHODS

In this study, 142 patients with gastric adenocarcinoma underwent laparoscopic gastrectomy at a Spanish hospital between January 2017 and December 2022. Of these, 42 patients received preoperative indocyanine green injection to guide lymphadenectomy. Their outcomes were compared to a retrospective cohort of 42 patients after 1:1 propensity score matching.

RESULTS

The feasibility of indocyanine green lymphatic mapping was 95.5%. No complications associated with indocyanine green injection were observed. The indocyanine green group had a significantly higher number of retrieved lymph nodes than the non-indocyanine green group (32.67 vs 25.14; P = .013). This statistically significant difference was maintained across subgroups of neoadjuvant treatment, non-obese patients, pT0 to 2 stage, and pN0 stage. In 47.6% of patients from the indocyanine green group, lymphadenectomy was extended outside the standard D2 dissection area based on indocyanine green uptake, but none of the retrieved lymph nodes were metastatic. There were no differences in postoperative complications and length of hospital stay between the 2 groups.

CONCLUSION

Indocyanine green-guided lymphadenectomy is safe and feasible and increases the number of retrieved lymph nodes compared to conventional lymphatic dissection, as well as in patients receiving neoadjuvant chemotherapy. The use of indocyanine green should be routine if available for guiding lymph node dissection in gastric cancer, regardless of tumor stage or previous neoadjuvant treatment. However, further studies are needed to determine the impact of this technique on disease-free and overall survival.

Subserosal Indocyanine Green Plus Submucosal Carbon Nanoparticle Navigated Laparoscopic Gastrectomy (DANCE-01): a Cohort Study

BACKGROUND

Indocyanine green (ICG) and carbon nanoparticle (CN) have been widely used for radical gastrectomy. However, synchronous application of ICG and CN in gastrectomy has not been tried yet. For the first time, we herein reported a novel strategy using dual tracers in laparoscopic radical gastrectomy.

METHODS

This is a single-center, single-armed, prospective study. For each qualified patient, submucosal CN was injected the day before surgery, and subserosal ICG was injected immediately before surgery. Standard D2 laparoscopic gastrectomy and lymph node examination were subsequently performed. Demographics, lymph nodes (LNs) and postoperative outcome were collected for analysis. To analyze the safety and efficacy of this novel strategy, two contemporary historic control groups using single tracer were established.

RESULTS

A total of 60 patients underwent dual tracer laparoscopic gastrectomy and were divided into distal (n = 41) and total (n = 19) groups. An average of 53.3 and 62.2 LNs was harvested from two groups, respectively. The average operation duration was 213.3 and 250.0 min, and intra-operative blood loss was 100.2 ml and 94.7 ml. None received combined organ resection. Margin negativity and R0 resection were achieved in all patients. Three (7.3%) complications occurred in distal group. None required second operation or deceased. Postoperative hospitalization was 9.7 and 9.6 days, respectively. Compared to single tracer, more LNs (p < 0.01), shorter operation time (p < 0.01), less blood lost (p < 0.01) and accelerated postoperative recovery (p < 0.01) were observed in dual tracer group.

CONCLUSIONS

We propose a novel, feasible and safe tracing strategy for laparoscopic gastrectomy.

CLINICAL TRIAL REGISTRATION

Chinese Clinical Trial Registry (ChiCTR2100051309).

Textbook outcome in oncological gastric surgery: a systematic review and call for an international consensus

BACKGROUND

Textbook outcome (TO) is a multidimensional measure used to assess the quality of surgical practice. It is a reflection of an "ideal" surgical result, based on a series of benchmarks or established reference points that may vary depending on the pathology in question. References to TO in the literature are scarce, and the few reports that are available were all published very recently. In the case of gastric surgery, there is no established consensus on the parameters that should be included in TO, a circumstance that prevents comparison between series.

AIM

To present a review of the literature on TO in gastric surgery (TOGS) and to try to establish a consensus on its definition.

MATERIAL AND METHODS

Following the PRISMA guide, we performed an unlimited search for articles on TOGS in the MEDLINE (PubMed), EMBASE and Cochrane, Latindex, Scielo, and Koreamed databases, without language restriction, updated on December 31, 2022. The inclusion criterion was any type of study assessing TO in adult patients after oncological gastric surgery. Selected studies were assessed, and TOGS was measured. The parameters used to assess the achievement of TOGS in selected studies were also recorded.

RESULTS

Twelve articles were included, comprising a total of 44,581 patients who had undergone an oncological gastric resection. The median rate of TOGS was 38.6%. All the publications but one included mortality as a TO variable, showing statistically significant differences in favor of the group in which TOGS was achieved. All articles included the number of nodes examined in the surgical specimen, with the assessment of fewer than 15 being associated with a low rate of TOGS achievement in five studies (41.7%). The variable postoperative complications according to the Clavien-Dindo score was the most important cause of failure to achieve TOGS in four studies (33.3%). Seven articles (58.3%) found a significant increase in long-term survival in patients who obtained TO. Advanced age, elevated ASA, and Charlson score had a negative impact on obtaining TOGS.

CONCLUSIONS

The standardization of TOGS is necessary to be able to establish comparable results between groups.

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.

New clinical application of indocyanine green in fluorescence-guided laparoscopic lymph-node biopsy in case of lymphoma. Preliminary results on a case series

BACKGROUND

Indocyanine Green (ICG) fluorescence-guided surgery is widely used for intraoperative visualization of lymphatic structures. To date, there are no reports indicating this dye being used in lymph node biopsies for suspected or relapsed lymphoma.

METHODS

Between October 2021 and June 2022, 12 patients underwent a fluorescence-guided laparoscopic lymph node biopsy (FGLLB) using ICG. The following was retrospectively evaluated: the dosage of ICG, the injection site, the number of patients where fluorescence was obtained after ICG administration, and additionally, the parameters indicating the outcome of the surgical procedure.

RESULTS

The median duration of the surgery was 90 min. A laparotomy conversion was required in one case due to bleeding. Fluorescence was obtained in 10/12 (83.3%) patients by means of subcutaneous/perilesional injection in six of the patients, and intravenously in the other four. Hospitalization had a mean duration of three days. There were no major postoperative complications. FGLLB was used in seven patients to follow lymphoproliferative disease progression, and in five patients to establish a diagnosis. In all cases, FGLLB provided the information necessary for the correct diagnosis.

CONCLUSIONS

Fluorescence with ICG offers a simple and safe method for detecting pathological lymph nodes. FGLLB in suspected intra-abdominal lymphoma can largely benefit from this new opportunity which has not yet been tested to date. Further studies with large case series are needed to confirm its efficacy.

Fluorescence-based sentinel lymph node mapping and lymphography evaluation: results from the IHU-IRCAD-EAES EURO-FIGS registry

BACKGROUND

The identification of metastatic lymph nodes is one of the most important prognostic factors in gastrointestinal (GI) cancers. Near-infrared fluorescence (NIRF) imaging has been successfully used in GI tumors to detect the lymphatic pathway and the sentinel lymph node (SLN), facilitating fluorescence image-guided surgery (FIGS) with the purpose to achieve a correct nodal staging. The aim of this study was to analyze the current results of NIRF SLN navigation and lymphography through data collected in the EURO-FIGS registry.

METHODS

Prospectively collected data regarding patients and ICG-guided lymphadenectomies were analyzed. Additional analyses were performed to identify predictors of metastatic SLN and determinants of fluorescence positivity and nodal metastases outside the boundaries of standard lymphadenectomies.

RESULTS

Overall, 188 patients were included by 18 surgeons from 10 different centers. Colorectal cancer was the most reported pathology (77.7%), followed by gastric (19.1%) and esophageal tumors (3.2%). ICG was injected with higher doses (p < 0.001) via extraparietal side (63.3%), and with higher volumes (p < 0.001) via endoluminal side (36.7%). Overall, NIRF SLN navigation was positive in 75.5% of all cases and 95.5% of positive SLNs were retrieved, with a metastatic rate of 14.7%. NIRF identification of lymph nodes outside standard lymphatic stations occurred in 52.1% of all cases, 43.8% of which were positive for metastatic involvement. Positive NIRF SLN identification was an independent predictor of metastasis outside standard lymphatic stations (OR = 4.392, p = 0.029), while BMI independently predicted metastasis in retrieved SLNs (OR = 1.187, p = 0.013). Lower doses of ICG were protective against NIRF identification outside standard of care lymphadenectomy (OR = 0.596, p = 0.006), while higher volumes of ICG were predictive of metastatic involvement outside standard of care lymphadenectomy (OR = 1.597, p = 0.001).

CONCLUSIONS

SLN mapping helps identifying potentially metastatic lymph nodes outside the boundaries of standard lymphadenectomies. The EURO-FIGS registry is a valuable tool to share and analyze European surgeons' practices.

Fluorescence-guided surgery: comprehensive review

BACKGROUND

Despite significant improvements in preoperative workup and surgical planning, surgeons often rely on their eyes and hands during surgery. Although this can be sufficient in some patients, intraoperative guidance is highly desirable. Near-infrared fluorescence has been advocated as a potential technique to guide surgeons during surgery.

METHODS

A literature search was conducted to identify relevant articles for fluorescence-guided surgery. The literature search was performed using Medical Subject Headings on PubMed for articles in English until November 2022 and a narrative review undertaken.

RESULTS

The use of invisible light, enabling real-time imaging, superior penetration depth, and the possibility to use targeted imaging agents, makes this optical imaging technique increasingly popular. Four main indications are described in this review: tissue perfusion, lymph node assessment, anatomy of vital structures, and tumour tissue imaging. Furthermore, this review provides an overview of future opportunities in the field of fluorescence-guided surgery.

CONCLUSION

Fluorescence-guided surgery has proven to be a widely innovative technique applicable in many fields of surgery. The potential indications for its use are diverse and can be combined. The big challenge for the future will be in bringing experimental fluorophores and conjugates through trials and into clinical practice, as well as validation of computer visualization with large data sets. This will require collaborative surgical groups focusing on utility, efficacy, and outcomes for these techniques.

Indocyanine green near-infrared imaging-guided lymph node dissection during oesophageal cancer surgery: A single-centre experience

Objective

This study aimed to investigate the feasibility of using indocyanine green (ICG) near-infrared (NIR) imaging during lymphadenectomy for oesophageal cancer.

Methods

Eighty-seven patients with primary oesophageal cancer were enrolled in this study. All the enrolled patients received an endoscopic injection of ICG between 40 min and 23 h before surgery. Nodal dissection during surgery was performed under fluorescence imaging visualisation, with the NIR signal shown in purple. ICG⁺ or ICG^- nodes were recorded station by station and were microscopically evaluated.

Results

Endoscopic peritumoral ICG injection was successfully performed in all patients. Major post-surgery complications included wound infection, pleural effusion, dysphonia, pneumonia and anastomotic fistula. No patients experienced ICG-related adverse events. A total of 2,584 lymph nodes were removed, and the mean number of lymph nodes for each patient was 29.70 ± 9.24. Most of the removed nodes (97.83%) were ICG⁺, and 3.32% of the ICG⁺ nodes were metastatic. No metastatic nodes were ICG^- or belonged to an ICG^- lymph node station. The time from ICG injection to surgery did not affect the number of harvested lymph nodes.

Conclusions

The use of ICG-NIR imaging during oesophageal cancer surgery can enhance the visualisation of lymph nodes during surgery. It is a feasible, safe and helpful technique for lymphadenectomy.

Textbook outcome in gastric surgery, what implications does it have on survival?

INTRODUCTION

The textbook outcome (TO) is a multidimensional measure to assess the quality of healthcare practice. This is reflected as the "ideal" surgical result, attending to a series of indicators or established reference points that are adapted depending on the surgical disease that we want to analyze. There are few references and series published about TO, all of them very recent.

OBJECTIVE

We present a series of gastric surgery from the TO perspective and we analyze its impact on survival.

METHOD

Retrospective observational study of all gastric neoplasms operated on in our center.

PERIOD

January 2015-December 2020. The criteria for TO were: margins R0, >15 lymph nodes in the histological study, no Clavien-Dindo complications > IIIa, hospital stay < 21 days, no mortality or readmission in the 30 postoperative days. A comparative analysis was performed between the TO group versus the non-TO group.

RESULTS

91 patients were operated on. We reached the TO in 34.1% of the patients. The variable >15 lymph nodes was the one that most affected to achieve a TO. When performing the survival analysis, we obtained that the group in which the TO was obtained had a greater survival (p < 0.008).

CONCLUSION

In our series, obtaining the TO has an impact on survival which 34,1% of degree of compliance.

Application of Intraoperative Fluorescence Imaging with Indocyanine Green in the Difficult Gallbladder: A Comparative Study between Indocyanine Green-Guided Fluorescence Cholangiography and Conventional Surgery

Background: In the difficult gallbladder, the rate of bile duct injury (BDI) remains high. To lessen iatrogenic biliary injury, we attempted to utilize indocyanine green (ICG)-guided fluorescence cholangiography during surgery to illuminate the extrahepatic biliary tract. Materials and Methods: According to admission criteria, 38 patients were diagnosed with difficult gallbladder and underwent percutaneous transhepatic gallbladder drainage (PTGBD). Consecutive patients who underwent ICG-assisted laparoscopic biliary surgery (n = 18, ICG group) or conventional laparoscopic biliary surgery (n = 20, white light [WL group) were enrolled in this study. ICG group received ICG fluorescent cholangiography via PTGBD tube during operation; 16 cases of laparoscopic cholecystectomy (LC) and 2 cases of LC plus laparoscopic common bile duct exploration (LC+LCBDE) were performed by fluorescent laparoscopy. In the WL group, 16 cases of LC, 1 case of laparoscopic subtotal cholecystectomy (LSC), and 3 cases of LC+LCBDE were performed under white light without ICG. Result: The biliary system was successfully established in the ICG group. Compared with the WL group, the anatomy of the Calot's triangle with severe abdominal adhesion or local inflammatory edema was more clearly displayed by fluorescence. Laparoscopic surgery was completed in both groups without conversion to laparotomy. There were no significant differences in surgery-related complications (P = .232) and postoperative hospital stay (P = .074) between the two groups. However, compared with the WL group, the ICG group had less intraoperative blood loss (P = .002) and shorter operation duration (P = .006). Conclusion: ICG fluorescence cholangiography has good clinical application value in the difficult gallbladder, which can avoid iatrogenic BDI, reduce surgery-related complications and intraoperative blood loss, and shorten the duration of surgery.

Retrospective cohort study of laparoscopic ICG-Guided Lymphadenectomy in gastric cancer from a Western country center

BACKGROUND

Indocyanine green (ICG) guided lymphadenectomy has been proposed has a technique to improve the lymphadenectomy of patients with gastric cancer. Nevertheless, experience with this procedure is scarce in Western countries.

METHODS

A retrospective analytic study in a tertiary hospital in Spain was performed, comparing patients who underwent laparoscopic gastrectomy with (ICG cohort) and without (historic cohort) ICG guided lymphadenectomy.

RESULTS

Thirty four patients were included (17 in each group). Although the number of positive nodes was similar in both groups (0.0 in the ICG cohort vs. 2 in the historic cohort, p = 0.119), the number of lymph nodes removed was higher in the ICG cohort (42.0 vs 28.0, p = 0.040). In the ICG cohort, more lymph nodes were positive for adenocarcinoma in the group of nodes that were positive for IGC (10.6% of the IGC + nodes vs. 1.9% in the ICG - nodes, p < 0.001).

CONCLUSIONS

ICG lymphadenectomy is a promising procedure that could improve the lymphadenectomy of patients with gastric cancer. ICG lymphadenectomy could be used to increase the number of lymph nodes removed in patients with a high-risk of nodal invasion or it could be used to reduce the surgical aggressiveness in fragile patients with a low-risk of nodal invasion.

Securing Resection Margin Using Indocyanine Green Diffusion Range on Gastric Wall during NIR Fluorescence-Guided Surgery in Early Gastric Cancer Patients

Near-infrared (NIR) fluorescence lymphography-guided minimally invasive gastrectomy using indocyanine green (ICG) is employed to visualize draining lymphatic vessels and lymph nodes. Endoscopically injected ICG spreads along the gastric wall and emits fluorescence from the serosal surface of the stomach. We aimed to assess the efficacy of ICG diffusion in securing the resection margin. We retrospectively analyzed 503 patients with early gastric cancer located in the body of the stomach who underwent fluorescence lymphography-guided gastrectomy from 2018 to 2021. One day before surgery, ICG was endoscopically injected into four points of the submucosal layer peritumorally. We measured the extent of resection and the resection line based on the ICG diffusion area from the specimen using NIR imaging. The mean area of the ICG diffusion was 82.7 × 75.3 and 86.7 × 80.2 mm2 on the mucosal and serosal sides, respectively. After subtotal gastrectomy, the length of the proximal resection margin was 38.1 ± 20.1, 33.4 ± 22.2, and 28.7 ± 17.2 mm in gastroduodenostomy, loop gastrojejunostomy, and Roux-en-Y gastrojejunostomy, respectively. The ICG diffusion area along the gastric wall secured a resection margin of >28 mm. The ICG diffusion range can be used as a simple and easy method for determining the resection margin during gastrectomy using NIR imaging.

Fluorescent Lymphography-Guided Lymphadenectomy during Minimally Invasive Completion Total Gastrectomy for Remnant Gastric Cancer Patients

Simple Summary

The altered lymphatic anatomy around the remnant stomach after initial surgery causes technical difficulties in systematic lymphadenectomy during the completion total gastrectomy. A fluorescent lymphography with indocyanine green under near-infrared imaging is a reliable intraoperative technique for lymphatic identification in minimally invasive gastric cancer surgery. This study aimed to assess the clinical application of fluorescent lymphography in minimally invasive completion total gastrectomy for remnant gastric cancer. More lymph node retrieval was demonstrated in minimally invasive completion total gastrectomy with fluorescent lymphography than without fluorescent lymphography. Fluorescent lymphography is an effective tool for the intraoperative assessment of lymphatics around the remnant stomach and systemic lymphadenectomy during minimally invasive completion total gastrectomy.

Abstract

No study has evaluated fluorescent lymphography for lymphadenectomy in remnant gastric cancer (RGC). This study aimed to assess the clinical application of fluorescent lymphography in minimally invasive completion total gastrectomy for RGC. Patients who had undergone minimally invasive completion total gastrectomy for RGC from 2013 to 2020 were retrospectively reviewed. The perioperative outcomes and long-term prognosis were compared between patients who had undergone minimally invasive completion total gastrectomy with fluorescent lymphography (the FL group) and those without fluorescent lymphography (the non-FL group). The FL group comprised 32 patients, and the non-FL group comprised 36 patients. FL visualized lymphatics in all 32 patients without complications related to the fluorescent injection. The median number [the interquartile range] of LN retrieval was significantly higher in the FL group (17 [9.3–23.5]) than in the non-FL group (12.5 [4–17.8]); p = 0.016). The sensitivity of fluorescent lymphography in detecting metastatic LN stations was 75%, and the negative predictive value was 96.9% in the FL group. The overall relapse-free survivals were comparable between the groups (p = 0.833 and p = 0.524, respectively). FL is an effective tool to perform a more thorough lymphadenectomy during minimally invasive completion total gastrectomy for RGC. Using FL in RGC surgery may improve surgical quality and proper staging.

Indocyanine Green Fluorescence-Guided Surgery for Gastrointestinal Tumors: A Systematic Review

Objective

To conduct a systematic review of the currently available literature on the use of ICG to guide surgical dissection in gastrointestinal (GI) cancer surgery.

Background

Real-time indocyanine green (ICG) fluorescence-guided surgery has the potential to enhance surgical outcomes by increasing patient-tailored oncological precision.

Methods

MEDLINE, PubMed, EMBASE, and Google Scholar were searched for publications on the use of ICG as a contrast agent in GI cancer surgery until December 2020. Perfusion studies were excluded. Quality of the studies was assessed with the Methodological Index for nonrandomized Studies or Jadad scale for randomized controlled trials. A narrative synthesis of the results was provided, with descriptive statistics when appropriate.

Results

Seventy-eight studies were included. ICG was used for primary tumor and metastases localization, for sentinel lymph node detection, and for lymph flow mapping. The detection rate for primary colorectal and gastric tumors was 100% after preoperative ICG endoscopic injection. For liver lesions, the detection rate after intravenous ICG infusion was 80% and up to 100% for lesions less than 8 mm from the liver surface. The detection rate for sentinel lymph nodes was 89.8% for esophageal, 98.6% for gastric, 87.4% for colorectal, and 83.3% for anal tumors, respectively. In comparative studies, ICG significantly increases the quality of D2 lymphadenectomy in oncological gastrectomy.

Conclusion

The use of ICG as a guiding tool for dissection in GI surgery is promising. Further evidence from high-quality studies on larger sample sizes is needed to assess whether ICG-guided surgery may become standard of care.

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.

Fluorescence-guided nodal navigation during colectomy for colorectal cancer

INTRODUCTION

Indocyanine green (ICG) fluorescence is an emerging technique in the surgical field. Among its various applications, it allows surgeons to have real-time visualization of the lymphatic drainage of an organ. The primary outcome of our study is the feasibility and safety of ICG-guided colorectal surgery. Our secondary outcome is the efficacy of ICG-guided lymphadenectomy and whether or not ICG positivity correlates with the identification of nodal metastasis.

MATERIAL AND METHODS

We conducted a single-center prospective study including 32 patients who underwent surgery for colorectal cancer. For each case, ICG was injected into the tumor area either prior to or during surgery. Tumor specimens and excised lymph nodes were analyzed using hematoxylin and eosin (H&E) staining.

RESULTS

In all patients, ICG injected in the tumor area allowed clear visualization of the lymphatic drainage. A total of 499 lymph nodes were collected, with a mean of 16 per patient. Fifty ICG positive lymph nodes outside the standard lymphadenectomy zone were examined; however, none of the nodes showed signs of nodal metastasis.

CONCLUSIONS

ICG-guided colorectal surgery is safe, feasible and easily reproducible, with a relatively low cost and no radiation exposure. ICG can help the surgeon to visualize the anatomical structures. We did not find an oncological diagnostic advantage in the use of ICG-guided nodal navigation.

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.

Applicative Limitations of Indocyanine Green Fluorescence Assistance to Laparoscopic Lymph Node Dissection in Total Gastrectomy for Cancer

BACKGROUND

Indocyanine green (ICG) fluorescence has been recently introduced as a novel imaging technique improving the accuracy of lymph node (LN) dissection in gastric cancer (GC) surgery, although procedure standardization and achievements have not been clearly defined. This study analyzed the feasibility and effectiveness of ICG-guidance for laparoscopic D2-lymphadenectomy during total gastrectomy for cancer.

METHODS

This study retrospectively analyzed a single-center series of patients who underwent laparoscopic total gastrectomy for cancer between April 2015 and August 2021. All patients underwent surgery with standard D2 LN dissection. Intraoperative ICG-fluorescence was institutionally implemented in April 2018 and was performed routinely afterward. Primary outcomes were LN harvest and ratio. Secondary endpoints included operative time and subgroup analysis to assess variables potentially affecting LN retrieval.

RESULTS

The study population included 102 patients, and ICG-fluorescence was applied in 38 (37.3%). ICG and no-ICG groups presented similar median age, gender proportions, ASA score and comorbidities (age-adjusted Charlson Comorbidity Index), body mass index, and advanced pathological stage. The median of LNs retrieved was significantly higher after the intraoperative ICG-guidance (44 vs. 32; p = 0.004), although this association was not significant after neoadjuvant therapy or among patients with positive LNs. Lymph node ratio and operative time were not significantly impacted by ICG fluorescence. Multivariate analysis identified the ICG-assistance as the only independent determinant for LN harvest (p = 0.029).

CONCLUSIONS

ICG-guidance contributes to a significantly wider LN retrieval after laparoscopic D2-lymphadenectomy during total gastrectomy for cancer. However, neoadjuvant therapy and positive LN stage appeared to limit the procedural effectiveness to ICG-assisted LN identification.

Laparoscopic Gastrectomy with ICG Guided D2 Lymph Node Dissection – A Case Report and Review of the Literature

Radical surgery for gastric cancer remains the only reliable therapeutic tool and cornerstone for definitive treatment. With improving resectability, patients are given a better opportunity for long-term survival. Indocyanine green (ICG) is able to define more precisely the boundaries of the tumor in early and advanced gastric cancer. In addition, it can noticeably improve lymph node dissection and reduce the risk of subsequent complications. In this paper we present our experience with laparoscopic gastrectomy together with a review of the available literature.

Efficacy and Safety of Totally Laparoscopic Gastrectomy Compared with Laparoscopic-Assisted Gastrectomy in Gastric Cancer: A Propensity Score-Weighting Analysis

Objectives

To compare the short- and long-term outcomes of totally laparoscopic gastrectomy (TLG) with laparoscopic-assisted gastrectomy (LAG) in gastric cancer (GC) patients and evaluate the efficacy and safety of TLG.

Methods

This retrospective study was based on GC patients who underwent laparoscopic radical gastrectomy in the Qilu Hospital from January 2017 to December 2020. The groups’ variables were balanced by using the propensity score-based inverse probability of treatment weighting (PS-IPTW). The primary outcomes were 3-year relapse-free survival (RFS) and 3-year overall survival (OS). Postoperative recovery and complications were the secondary outcomes.

Results

A total of 250 GC patients were included in the study. There were no significant differences in baseline and pathological features between the TLG and the LAG groups after the PS-IPTW. TLG took around 30 min longer than LAG, while there were more lymph nodes obtained and less blood loss throughout the procedure. TLG patients had less wound discomfort than LAG patients in terms of short-term prognosis. There were no significant differences between groups in the 3-year RFS rate [LAG vs. TLG: 78.86% vs. 78.00%; hazard ratio (HR) = 1.14, 95% confidence interval (CI), 0.55–2.35; p = 0.721] and the 3-year OS rate (LAG vs. TLG: 78.17% vs. 81.48%; HR = 0.98, 95% CI, 0.42–2.27; p = 0.955). The lymph node staging was found to be an independent risk factor for tumor recurrence and mortality in GC patients with laparoscopic surgery. The subgroup analysis revealed similar results of longer operation time, less blood loss, and wound discomfort in totally laparoscopic distal gastrectomy, while the totally laparoscopic total gastrectomy showed benefit only in terms of blood loss.

Conclusion

TLG is effective and safe in terms of short- and long-term outcomes, with well-obtained lymph nodes, decreased intraoperative blood loss, and postoperative wound discomfort, which may be utilized as an alternative to LAG.

Role of Qualitative and Quantitative Indocyanine Green Angiography to Assess Mastectomy Skin Flaps Perfusion in Nipple/Skin-Sparing and Skin-Reducing Mastectomies with Implant-Based Breast Reconstruction

Methods

Consecutive women scheduled for nipple/skin-sparing/skin-reducing mastectomy between May 2020 and April 2021 were prospectively enrolled. Patients were divided into Group 1 in the absence of superficial and full-thickness necrosis (SN; FTN) and Group 2 in the presence of both. T1 (time between ICG injection and the initial perfusion of the least perfused MSF area), ICG-Q1, and ICG-Q% (absolute and relative perfusion values of the least vascularized area) were collected.

Results

38 breasts were considered. FTN was reported in 4 breasts (10.5%) and SN in 3 (7.9%). The two groups statistically differ in T1 (Group2 > Group1) and ICG-Q% (Group1 > Group2) (p < 0.05). T1 could statistically predict ICG-Q1 and ICG-Q%. Both quantitative values have a sensitivity of 57% and a NPV of 89%; ICG-Q% shows higher specificity (81% vs 77%) and PPV (40% vs 36%).

Conclusions

Quantitative ICG angiography may additionally reduce MSF necrosis. Moreover, longer T1 may indicate possible postoperative necrosis. Considering these factors, intraoperative changes of reconstructive strategy could be adopted to reduce reconstructive failure.

Assessment of indocyanine green fluorescence lymphography on lymphadenectomy during minimally invasive gastric cancer surgery: a systematic review and meta-analysis

BACKGROUND

In recent years, indocyanine green fluorescence lymphography has been introduced for lymphatic mapping in gastric cancer surgery. The aim of this study was to investigate the efficacy of ICGFL in lymph node dissection during minimally invasive surgery for gastric cancer.

METHODS

A systematic review of electronic databases including PubMed, Embase, Web of Science, the Cochrane Library, and China National Knowledge Infrastructure was performed from the inception to January 2021 for all studies comparing ICGFL with non-ICGFL in GC patients undergoing minimal access gastrectomy. The primary outcome was the total number of harvested lymph nodes. The secondary endpoints were the number of metastatic LNs, operative time, estimated blood loss, and postoperative complications. The registration number of this protocol is PROSPERO CRD42020203443.

RESULTS

A total of 13 studies including 1882 participants were included. In this meta-analysis, the use of ICGFL was associated with a higher number of harvested LNs (40.33 vs. 33.40; MD = 6.93; 95%CI: 4.28 to 9.58; P < 0.0001; I2 = 86%). No significant difference was found between the ICGFL and control groups in terms of metastatic LNs (2.63 vs. 2.42; MD = 0.21; 95%CI: -0.46 to 0.87; P = 0.54; I2 = 0%). In addition, the use of ICGFL could be safely performed without increasing the operative time (P = 0.49), estimated blood loss (P = 0.26) and postoperative complications (P = 0.54).

CONCLUSION

The use of ICGFL may be a useful tool facilitating complete lymph node dissection during minimally invasive GC resection. However, more high-quality RCTs with large sample size are needed to validate this issue.

Surgeon-Pathologist Team Approach Dramatically Affects Lymph Nodes Detection and Improves Patients' Short-Term Outcome

Simple Summary

Appropriate lymph node harvesting for patients with gastric cancer is fundamental for a correct staging and is strongly related to survival. In this study, we present a new protocol for on-site macroscopic evaluation and sampling of lymph nodes for gastric cancer patients. With the joint collaboration of surgeons and pathologists, our method aims to provide the largest possible number of analyzed lymph nodes per patient, allowing for a better staging. We are convinced that this approach is routinely feasible, and our preliminary results seem to confirm better patient stratification compared to other lymph node dissection methods.

Abstract

The downstaging of gastric cancer has recently gained particular attention in the field of gastric cancer surgery. The phenomenon is mainly due to an inappropriate sampling of lymph nodes during standard lymphadenectomy. Hence, collection of the maximum number of lymph nodes is a critical factor affecting the outcome of patients. None of the techniques proposed so far have demonstrated a real efficiency in increasing the number of identified lymph nodes. To harvest the maximum number of lymph nodes, we designed a protocol for on-site macroscopic evaluation and sampling of lymph nodes according to the Japanese Gastric Cancer Association protocol. The procedure was carried out by a surgeon/pathologist team in the operating room. We enrolled one hundred patients, 50 of whom belonged to the study group and 50 to a control group. The study group included patients who underwent lymph node dissection following the proposed protocol; the control group encompassed patients undergoing standard procedures for sampling. We compared the number and maximum diameter of lymph nodes collected in both groups, as well as some postoperative variables, the 30-day mortality and the overall survival. In the study group, the mean number of lymph nodes harvested was higher than the control one (p = 0.001). Moreover, by applying the proposed technique, we sampled lymph nodes with a very small diameter, some of which were metastatic. Noticeably, no difference in terms of postoperative course was identified between the two groups, again supporting the feasibility of an extended lymphadenectomy. By comparing the prognosis of patients, a better overall survival (p = 0.03) was detected in the study group; however, to date, no long-term follow-up is available. Interestingly, patients with metastasis in node stations number 8, 9, 11 or with skip metastasis, experienced a worse outcome and died. Based on our preliminary results, the pathologist/surgeon team approach seems to be a reliable option, despite of a slight increase in sfaff workload and technical cost. It allows for the harvesting of a larger number of lymph nodes and improves the outcome of the patients thanks to more precise staging and therapy. Nevertheless, since a higher number of patients are necessary to confirm our findings and assess the impact of this technique on oncological outcome, our study could serve as a proof-of-concept for a larger, multicentric collaboration.

Kynurenine and Anthranilic Acid in the Peritoneum Correlate With the Stage of Gastric Cancer Disease

BACKGROUND

This study aimed to assess the importance of selected kynurenines measured in peritoneal fluid, lavage washings, and blood serum in patients with advanced gastric cancer (GC) based on the clinical and pathological staging of TNM for a more precise evaluation of the stage of the disease.

METHODS

Data were collected from a prospectively maintained database of all patients operated on advanced GC between July 2018 and August 2020. In total, 98 patients were eligible for the analysis according to the REMARK guidelines.

RESULTS

Among the various kynurenines analyzed in this study, we found that the median concentration of anthranilic acid (AA) in the peritoneal lavage washings was significantly higher in patients with positive nodes (pN1-3) compared to those with negative nodes (pN0) (P = 0.0100). Based on the ROC analysis, AA showed diagnostic utility in the differentiation of the pN staging (P = 0.0047). Furthermore, there was a positive correlation between AA in peritoneal fluid with stage pN (P = 0.0116) and a positive correlation between AA in peritoneal lavage washings with stage cT (P = 0.0101). We found that the median concentration of kynurenine (Kyn) in peritoneal lavage washings was significantly higher in patients with cM1 compared to cM0 patients (P = 0.0047). Based on the ROC analysis, Kyn showed diagnostic utility in cM staging differentiation (P < 0.0001). There was a positive correlation between peritoneal Kyn and stage of cM (P = 0.0079).

CONCLUSIONS

AA and Kyn measured in peritoneal lavage indicate advanced GC and may be considered in the future as valuable adjunct tools in TNM staging of advanced GC.

Comparison of submucosal and subserosal approaches toward optimized indocyanine green tracer-guided laparoscopic lymphadenectomy for patients with gastric cancer (FUGES-019): a randomized controlled trial

BACKGROUND

Application of indocyanine green (ICG) fluorescence imaging is effective in guiding laparoscopic radical lymphadenectomy for gastric cancer. However, the optimal approach for indocyanine green injection is controversial. Therefore, the objective of this study was aimed to compare the efficacy and ICG injection between the preoperative submucosal and intraoperative subserosal approaches for lymph node (LN) tracing during laparoscopic gastrectomy.

METHOD

This randomized controlled trial (ClinicalTrials.gov, NCT04219332) included 266 patients with potentially resectable gastric cancer (cT1-T4a, N0/+, M0) enrolled from a tertiary teaching center between December 2019 and October 2020. The primary endpoint was total number of retrieved LNs.

RESULTS

In total, 259 patients (n = 130 and n = 129 in the submucosal and subserosal groups, respectively) were included in the per-protocol analysis. There are no significant differences in total number of retrieved LNs between the two groups (49.8 vs. 49.2, P = 0.713). The rate of LN noncompliance in the submucosal group was comparable to that in the subserosal group (32.3% vs. 33.3%, P = 0.860). No significant difference was found between the submucosal and subserosal groups in terms of the incidence (17.7% vs. 16.3%; P = 0.762) or severity of postoperative complications. The mean fluorescence cost in the submucosal group was higher than that in the subserosal group ($335.3 vs. $182.4; P < 0.001). The overall treatment satisfaction score was lower in the submucosal group than in the subserosal group (70.5 vs. 76.1%, P = 0.048).

CONCLUSION

ICG administered by subserosal injection was comparable to that administered by submucosal injection for lymph node tracing in gastric cancer. However, the former approach imposed a lower economic and mental burden on patients undergoing laparoscopic D2 lymphadenectomy.

TRIAL REGISTRATION

ClinicalTrials.gov, NCT04219332 .

Clinical implications of Indocyanine Green Fluorescence Imaging-Guided laparoscopic lymphadenectomy for patients with gastric cancer: A cohort study from two randomized, controlled trials using individual patient data

BACKGROUND

The value of indocyanine green (ICG) fluorescence imaging in tracing metastatic lymph nodes (LNs) has rarely been reported. We aimed to evaluate the clinical implications of fluorescence imaging-guided lymphadenectomy and the sensitivity of fluorescent lymphography to detect metastatic LN stations in gastric cancer (GC).

MATERIALS AND METHODS

This analysis pooled data from two randomized controlled trials (FUGES-012 and FUGES-019 studies) on laparoscopic ICG tracer-guided lymphadenectomy for GC between November 2018 and October 2020. Patients who received ICG injection using either the intraoperative subserosal or preoperative submucosal approaches 1 day before surgery and underwent fluorescence imaging-guided lymphadenectomy were defined as the ICG group. Patients who underwent conventional lymphadenectomy without ICG injection and intraoperative imaging were defined as the non-ICG group.

RESULTS

Among 514 enrolled patients, the ICG and non-ICG groups included 385 and 129, respectively. A significantly higher mean number of LNs was retrieved in the ICG group than in the non-ICG group (49.9 vs. 42.0, P < 0.001). The ICG group showed a lower LN noncompliance rate than that in the non-ICG group (31.9% vs. 57.4%, P < 0.001). The sensitivity of fluorescence imaging for detecting all metastatic LN stations was 86.8%. The negative predictive value was 92.2% for nonfluorescent stations. For detecting all metastatic stations, subgroup analysis revealed 97.7%, 91.7%, 86.2%, and 84.3% sensitivities for pT1, pT2, pT3, and pT4a tumors, respectively. Regardless of gastrectomy type, the diagnostic accuracy for detecting all metastatic stations in the D1+ and D2 stations for cT1-cT2 disease reached 100%.

CONCLUSION

ICG fluorescence imaging, using either the subserosal or submucosal approaches, assisted in the thorough dissection of potentially metastatic LNs, as recommended for individualized laparoscopic lymphadenectomy for GC.

Lymph Node Involvement in Advanced Gastric Cancer in the Era of Multimodal Treatment-Oncological and Surgical Perspective

Simple Summary

Gastric cancer (GC) continues to be one of the major oncological challenges on a global scale. The role of neoadjuvant chemotherapy (NAC) in GC is to downstage primary tumour, eliminate potential micrometastases, and increase the chance for radical resection. Although systemic treatment prolongs the survival in advanced GC, persistent lymph node (LN) metastases indicate poor prognosis. Therefore, further identification of prognostic factors after NAC is urgent and could positively influence clinical outcomes. This article aimed to review the actual trends and future perspectives in multimodal therapy of advanced GC, with a particular interest in the post-neoadjuvant pathological nodal stage. Since downstaged and primarily node-negative patients show a similar prognosis, the main target for NAC in advanced GC should be nodal clearance. Adequate staging and personalised perioperative therapy seem to be of great importance in the multimodal treatment of GC.

Abstract

Gastric cancer (GC) continues to be one of the major oncological challenges on a global scale. The role of neoadjuvant chemotherapy (NAC) in GC is to downstage primary tumour, eliminate potential micrometastases, and increase the chance for radical resection. Although systemic treatment prolongs the survival in advanced GC, persistent lymph node (LN) metastases indicate poor prognosis. Further identification of prognostic factors after NAC is urgent and could positively influence clinical outcomes. This article aimed to review the actual trends and future perspectives in multimodal therapy of advanced GC, with a particular interest in the post-neoadjuvant pathological nodal stage. A favourable prognostic impact for ypN0 patients is observed, either due to truly negative LN before the start of therapy or because preoperative therapy achieved a pathologically complete nodal response. Ongoing trials investigating the extent of lymphadenectomy after neoadjuvant therapy will standardise the LN dissection from the multimodal therapy perspective. Since downstaged and primarily node-negative patients show a similar prognosis, the main target for NAC in advanced GC should be nodal clearance. Adequate staging and personalised perioperative therapy seem to be of great importance in the multimodal treatment of GC.