Application of fluorescence in robotic general surgery: review of the literature and state of the art

Indocyanine green fluorescence-guided surgery in the emergency setting: the WSES international consensus position paper

BACKGROUND

Decision-making in emergency settings is inherently complex, requiring surgeons to rapidly evaluate various clinical, diagnostic, and environmental factors. The primary objective is to assess a patient's risk for adverse outcomes while balancing diagnoses, management strategies, and available resources. Recently, indocyanine green (ICG) fluorescence imaging has emerged as a valuable tool to enhance surgical vision, demonstrating proven benefits in elective surgeries.

AIM

This consensus paper provides evidence-based and expert opinion-based recommendations for the standardized use of ICG fluorescence imaging in emergency settings.

METHODS

Using the PICO framework, the consensus coordinator identified key research areas, topics, and questions regarding the implementation of ICG fluorescence-guided surgery in emergencies. A systematic literature review was conducted, and evidence was evaluated using the GRADE criteria. A panel of expert surgeons reviewed and refined statements and recommendations through a Delphi consensus process, culminating in final approval.

RESULTS

ICG fluorescence imaging, including angiography and cholangiography, improves intraoperative decision-making in emergency surgeries, potentially reducing procedure duration, complications, and hospital stays. Optimal use requires careful consideration of dosage and timing due to limited tissue penetration (5-10 mm) and variable performance in patients with significant inflammation, scarring, or obesity. ICG is contraindicated in patients with known allergies to iodine or iodine-based contrast agents. Successful implementation depends on appropriate training, availability of equipment, and careful patient selection.

CONCLUSIONS

Advanced technologies and intraoperative navigation techniques, such as ICG fluorescence-guided surgery, should be prioritized in emergency surgery to improve outcomes. This technology exemplifies precision surgery by enhancing minimally invasive approaches and providing superior real-time evaluation of bowel viability and biliary structures-areas traditionally reliant on the surgeon's visual assessment. Its adoption in emergency settings requires proper training, equipment availability, and standardized protocols. Further research is needed to evaluate cost-effectiveness and expand its applications in urgent surgical procedures.

Real-Time Fluorescence Imaging for Thoracic Duct Identification during Oesophagectomy: A Systematic Review of the Literature

Postoperative chylothorax is a serious complication after oesophagectomy. Real-time identification of the thoracic duct (TD) could prevent injury or facilitate prompt management when it occurs. Intraoperative TD lymphography with indocyanine green (ICG) is a novel technique that may help prevent chyle leaks following thoracic surgery. A systematic search of PubMed, Embase, MEDLINE, Scopus, and the Cochrane Library for studies published until July 2024 evaluating ICG for TD identification during oesophagectomy was performed. Studies were included in the review if they assessed intraoperative TD identification with ICG to prevent chyle leakage in patients undergoing oesophagectomy. Nine of 265 screened papers were included in the present review, with 3 reporting comparative techniques of TD identification between patients. Only 1 study had a control group without ICG administration. TD was identified in 281 of the 303 patients who received ICG. Chyle leak incidence was 0.66% in the ICG group. The mean observation time of TD after ICG administration was 162 minutes. Most of the included patients received neoadjuvant treatment before surgery. Different application routes of ICG have been reported, with the most prominent one being through the inguinal region under ultrasound guidance. Real- time TD identification with ICG might be a valuable tool for avoiding injury or managing it intraoperatively. To our knowledge, this is the first systematic review on this complex topic. However, as no randomized controlled trials have been published, sufficient evidence is needed to determine whether the aforementioned method can sufficiently reduce the chyle leak rate.

Indocyanine green in gynecologic surgery: Where do we stand? A literature review and meta-analysis

The main objective of this study was to review and perform a meta-analysis of current literature on the use of indocyanine green for sentinel lymph node detection in pelvic gynecologic cancer. We included all studies focusing on indications and procedures associated with the use of ICG in gynecologic surgery and available on the Medline and Pubmed database. For the meta-analysis, random effect models were used for estimation of the 95 % detection rate and 95 % confidence interval, and stratified analyses by cancer type, concentration and localization of injection were performed. A total of 147 articles were included, of which 91 were studied in a meta-analysis. Results concerning detection rate by indocyanine green injection site were found to be 95.1 % and 97.3 % respectively for intracervical injection in 2 or 4 quadrants, and 77.0 % and 94.8 % for hysteroscopic and intradermal injection respectively. Results concerning detection rate by cancer type were 95.8 %, 95.2 %, 94.7 % and 95.7 % respectively for cervical, endometrial, vulvar and endometrial/cervical cancers. Finally, the results concerning detection rate by indocyanine green concentration were 91.2 %, 95.7 %, 96.7 % and 97.7 % for concentrations of <1.25 mg/ml, 1.25 mg/ml, 2.5 mg/ml and 5 mg/ml respectively. In conclusion, indocyanine green is shown to allow highlighting of sentinel lymph nodes with good reliability with an overall indocyanine green detection rate of 95.5 %. Our literature review revealed that indocyanine green feasibility has also been demonstrated in several surgical contexts, notably for reconstructive surgery and detection of endometriosis.

Robotic vs. laparoscopic distal gastrectomy for gastric cancer: A propensity score-matched retrospective comparative study at a single institution

BACKGROUND

Although robotic surgery is becoming more widespread worldwide, it is still in its infancy. This study aimed to confirm the safety and feasibility of the induction of robotic-assisted gastric surgery at a local hospital.

METHODS

For five years, between 2016 and 2020, 42 laparoscopic and 71 robotic distal gastrectomies were performed at the same institution. Patients diagnosed with gastric cancer were retrieved from the database. Propensity score matching was performed based on covariates such as Age, Sex, BMI, the American Society of Anesthesiologists Physical Status, Tumor Location, pT, and pN. Clinicopathological characteristics, surgical performance, postoperative outcomes, and pathological data were retrospectively collected and compared by the Chi-square test, the Fisher's exact test, the Student's t-test, and the Mann-Whitney U test.

RESULTS

Billroth II reconstruction was often selected for the robotic group more than the laparoscopic group (59.4% and 15.6%, respectively). In addition, the number of lymph nodes harvested after D2 dissection tended to be more significant in the robotic group than in the laparoscopic group (52.1 ± 7.6 and 29.1 ± 3.7, respectively; p = 0.00934). The mean operative time was 271.4 ± 10.5 min for the robotic group and 220.8 ± 12.3 min for the laparoscopic group (p = 0.00005). There were no differences in short-term clinical outcomes between the two groups.

CONCLUSIONS

Although a single-center, small comparative study, the results showed that the robotic surgery group was not inferior to the laparoscopic group in feasibility and safety. Moreover, robotic surgery enables harvesting a higher number of lymph nodes, which may be more advantageous than laparoscopic surgery. This study also showed that as the surgeon gains experience with robotic surgery, its operative time becomes significantly shorter.

From organ preservation to selective surgery: How immunotherapy changes colorectal surgery?

The emergence of immunotherapy has revolutionized the traditional treatment paradigm of colorectal cancer (CRC). Among them, immune checkpoint blockade has become the first-line treatment for metastatic colorectal cancer (mCRC) and has made significant progress in the treatment of locally advanced colorectal cancer (LACRC). We reviewed a series of clinical trials that have made breakthrough progress. We will emphasize the breakthrough progress in achieving organ preservation in patients with high microsatellite instability or DNA mismatch repair deficiency (MSI-H/dMMR), and based on this, we propose the concept of selective surgery, which includes selectively removing or preserving lymph nodes, with the aim of proving our idea through more research in the future.

Bibliometric analysis of robotic surgery research in breast cancer conducted between 2008 and 2022

BACKGROUND

To carry out a bibliometric analysis of robotic surgery research in the field of breast cancer conducted between 2008 and 2022 and to evaluate the status and trends in the field.

METHODS

A systematic search was undertaken in the Web of Science (WoS) for published articles related to surgical robots and breast cancer. R and VOSviewer software were used to carry out a quantitative analysis to explore the trend of annual publication volume and the cooperative relationship between countries, institutions, authors, and keywords.

RESULTS

A total of 177 publications were retrieved, 79.66% of which were published from 2016 to 2022, and most were conducted in the United States (US), China, and South Korea. Articles from the US had the most frequent international cooperation. A tally of institutional publications showed that Yonsei University (YONSEI UNIV; Korea) had produced the most publications. The author with the most published papers was Lee of YONSEI UNIV. The most accepted journal was the Asian Journal of Surgery. Keyword co-occurrence analysis showed that current research hotspots were mainly focused on nipple-conserving mastectomy and breast reconstruction, and breast-conserving and nipple-conserving mastectomy may be future research hotspots.

CONCLUSIONS

The annual incidence of robotic surgery and breast cancer is gradually increasing. The predominant countries conducting research in this field include the US, China, and South Korea, and the institutions are mainly distributed in universities and hospitals. Nipple-conserving mastectomy and breast reconstruction may be the current research hotspots, and breast-conserving mastectomy and minimally invasive surgery may represent hot research areas in the future. These findings may help scholars who are committed to the application of surgical robots to breast cancer to better understand the current research status and trends.

Quantifying the Impact of Signal-to-background Ratios on Surgical Discrimination of Fluorescent Lesions

PURPOSE

Surgical fluorescence guidance has gained popularity in various settings, e.g., minimally invasive robot-assisted laparoscopic surgery. In pursuit of novel receptor-targeted tracers, the field of fluorescence-guided surgery is currently moving toward increasingly lower signal intensities. This highlights the importance of understanding the impact of low fluorescence intensities on clinical decision making. This study uses kinematics to investigate the impact of signal-to-background ratios (SBR) on surgical performance.

METHODS

Using a custom grid exercise containing hidden fluorescent targets, a da Vinci Xi robot with Firefly fluorescence endoscope and ProGrasp and Maryland forceps instruments, we studied how the participants' (N = 16) actions were influenced by the fluorescent SBR. To monitor the surgeon's actions, the surgical instrument tip was tracked using a custom video-based tracking framework. The digitized instrument tracks were then subjected to multi-parametric kinematic analysis, allowing for the isolation of various metrics (e.g., velocity, jerkiness, tortuosity). These were incorporated in scores for dexterity (Dx), decision making (DM), overall performance (PS) and proficiency. All were related to the SBR values.

RESULTS

Multi-parametric analysis showed that task completion time, time spent in fluorescence-imaging mode and total pathlength are metrics that are directly related to the SBR. Below SBR 1.5, these values substantially increased, and handling errors became more frequent. The difference in Dx and DM between the targets that gave SBR < 1.50 and SBR > 1.50, indicates that the latter group generally yields a 2.5-fold higher Dx value and a threefold higher DM value. As these values provide the basis for the PS score, proficiency could only be achieved at SBR > 1.55.

CONCLUSION

By tracking the surgical instruments we were able to, for the first time, quantitatively and objectively assess how the instrument positioning is impacted by fluorescent SBR. Our findings suggest that in ideal situations a minimum SBR of 1.5 is required to discriminate fluorescent lesions, a substantially lower value than the SBR 2 often reported in literature.

Indocyanine Green Endoscopy for Pituitary Adenomas with Parasellar Extension: Results from a Preliminary Case Series

BACKGROUND

Advances in visualization tools have brought new confidence, including endoscope-integrated indocyanine (E-ICG), which makes pituitary and skull-base surgery safer and more effective. We report here our preliminary experience with the use of E-ICG to 1) visualize the cavernous segment of the internal carotid artery (ICA); and 2) functionally and anatomically preserve the pituitary gland.

METHODS

A dedicated ICG-integrated endoscope was used in 15 patients with parasellar pituitary adenomas. Indocyanine was administered at 2 different time points during surgery: an early bolus of 12.5 mg at the sphenoid sinus opening to expose the position of the parasellar segment of the ICAs and to identify the position of the normal pituitary gland so that it could be preserved during tumor removal. Subsequently, a second late bolus of 12 mg of ICG was injected to obtain a real-time "wire angiographic" visualization of the flow of the ICAs.

RESULTS

Gross total resection was achieved in 12 cases (80%), whereas subtotal resection was performed in the other 3 cases (20%). The pituitary gland was clearly discernable in 11 cases (91.6%). None of the patients manifested new endocrinologic deficits or major vascular complications.

CONCLUSIONS

E-ICG is a safe and essential aid for pituitary adenomas invading the cavernous sinus. Its performance as a pituitary marker and real-time video angiography showed promising results in terms of extent of resection, endocrinologic outcomes, and prevention of intraoperative complications.

The complementary value of intraoperative fluorescence imaging and Raman spectroscopy for cancer surgery: combining the incompatibles

A clear margin is an important prognostic factor for most solid tumours treated by surgery. Intraoperative fluorescence imaging using exogenous tumour-specific fluorescent agents has shown particular benefit in improving complete resection of tumour tissue. However, signal processing for fluorescence imaging is complex, and fluorescence signal intensity does not always perfectly correlate with tumour location. Raman spectroscopy has the capacity to accurately differentiate between malignant and healthy tissue based on their molecular composition. In Raman spectroscopy, specificity is uniquely high, but signal intensity is weak and Raman measurements are mainly performed in a point-wise manner on microscopic tissue volumes, making whole-field assessment temporally unfeasible. In this review, we describe the state-of-the-art of both optical techniques, paying special attention to the combined intraoperative application of fluorescence imaging and Raman spectroscopy in current clinical research. We demonstrate how these techniques are complementary and address the technical challenges that have traditionally led them to be considered mutually exclusive for clinical implementation. Finally, we present a novel strategy that exploits the optimal characteristics of both modalities to facilitate resection with clear surgical margins.

Application of the indocyanine green fluorescence imaging method in laparoscopic resection of a solitary retroperitoneal metastasis of renal cell carcinoma: A case report

Fluorescence image-guided surgery has improved intraoperative identification of anatomic structures including visualization of vascular anatomy. Herein, indocyanine green (ICG) fluorescence imaging was applied to identify of a recurrent small tumor of renal cell carcinoma (RCC) during laparoscopic surgery. The patient underwent left laparoscopic radical nephrectomy via the retroperitoneal approach for RCC (clear cell carcinoma, pT1bN0M0) at the age of 39 years. A solitary retroperitoneal mass (14 mm in diameter) was identified in a computed tomography scan 6 years after surgery. We performed laparoscopic resection with the application of the ICG angiography, because RCC is recognized as one of the most hypervascular cancers. The tumor was clearly visualized by fluorescence. Histopathological diagnosis of the resected tumor was recurrent RCC (low grade, G1). The patient remained free of disease at 2 years after surgery. The ICG fluorescence imaging would be a useful method for identification of metastatic small lesions of RCC during laparoscopic surgery.

Immunofluorescence in Robotic Colon and Rectal Surgery

The indocyanine green fluorescence imaging system is a surgical tool with increasing applications in colon and rectal surgery that has received growing acceptance in various surgical disciplines as a potentially valid method to enhance surgical field visualization, improve lymph node retrieval, and decrease anastomotic leak. Small noncomparative prospective trials have shown that intraoperative fluorescence imaging is a safe and feasible method to assess anastomotic perfusion and that its use may impact anastomotic leak rates. However, larger prospective and randomized studies are required to validate its role and impact in colorectal surgery. The purpose of this article is to review the current status of the use of immunofluorescence in colon and rectal surgery, as well as new applications in robotic colon and rectal resections.

Experimental validation of manipulability optimization control of a 7-DoF serial manipulator for robot-assisted surgery

PURPOSE

Both safety and accuracy are of vital importance for surgical operation procedures. An efficient way to avoid the singularity of the surgical robot concerning safety issues is to maximize its manipulability in robot-assisted surgery. The goal of this work was to validate a dynamic neural network optimization method for manipulability optimization control of a 7-degree of freedom (DoF) robot in a surgical operation.

METHODS

Three different paths, a circle, a sinusoid and a spiral were chosen to simulate typical surgical tasks. The dynamic neural network-based manipulability optimization control was implemented on a 7-DoF robot manipulator. During the surgical operation procedures, the manipulability of the robot manipulator and the accuracy of the surgical operation are recorded for performance validation.

RESULTS

By comparison, the dynamic neural network-based manipulability optimization control achieved optimized manipulability but with a loss of the accuracy of trajectory tracking (the global error was 1 mm compare to the 0.5 mm error of non-optimized method).

CONCLUSIONS

The method validated in this work achieved optimized manipulability with a loss of error. Future works should be introduced to improve the accuracy of the surgical operation.

Clinical Use of Indocyanine Green in Bowel Endometriosis Surgery

STUDY OBJECTIVE

To show feasibility of using indocyanine green (ICG) in endometriosis surgery, especially bowel endometriosis shaving, and to discuss its potential benefits.

DESIGN

Stepwise demonstration of this technique with narrated video footage.

SETTING

Endometriosis is a common benign chronic disorder, characterized by the presence of endometrial tissue outside the uterus. Deep infiltrating endometriosis (DIE) represents the most aggressive presentation. Robot-assisted laparoscopy represents an important innovation and has opened new perspectives for the treatment of endometriosis, offering numerous advantages especially in the most complex procedures, particularly when extragenital endometriosis diffusely involves pelvic structures including the bowel and the urinary tract [1]. Endometriosis affects the bowel in 30% of DIE cases, and it is usually associated with ovarian and ureteral involvement; therefore, a multidisciplinary team with both general and gynecologic surgeons is required. The goal of endometriosis surgery in these cases is to obtain long-term outcomes without compromising intestinal function. One possible treatment is laparoscopic shave excision, which consists of dissection, keeping it as superficial as possible to avoid compromising bowel integrity [2]. Recent studies have shown that ICG can be useful to evaluate the size and depth of penetration of lesions during endometriosis surgery to understand shaving excision and to prevent a major iatrogenic intestinal complication [3-7].

INTERVENTIONS

Total robot-assisted laparoscopic approach to a DIE case with adnexal, uterine, and intestinal endometriosis, with the presence of a nodular rectal lesion. The excision consisted of several key strategies to minimize iatrogenic rectal injury: CONCLUSION: The approach to DIE, particularly rectal endometriotic lesions, could be more accurate with ICG evaluation of vascular pertinence, in attempt to evaluate shaving feasibility of lesions in endometriosis laparoscopic robotic surgery.

Evolution of photodynamic medicine based on fluorescence image-guided diagnosis using indocyanine green and 5-aminolevulinic acid

New diagnostic techniques based on photodynamic medicine, such as near-infrared fluorescence using indocyanine green (NIR-ICG) and 5-aminolevulinic acid-mediated photodynamic diagnosis (ALA-PDD), are aiding navigation tasks across various fields of surgery. Specifically, NIR-ICG is being used for the intraoperative identification of sentinel lymph nodes or blood vessels in organ resection and for blood flow evaluation in surgery. These ICG-fluorescent imaging techniques could provide an additional and potentially valuable way to identify vascular and lymphatic structures in surrounding tissue. 5-Aminolevulinic acid is a precursor of a photosensitizing substance with affinity for tumors; thus, diagnostic laparoscopy using ALA-PDD in combination should improve the accuracy of detecting peritoneal dissemination in patients with advanced gastric cancer. The ability to overlay fluorescent imaging with conventional color images in real time using ALA-PDD and NIR with ICG would be of immense benefit to surgeons, providing good visualization and detection of target lesions not seen with the naked eye. A multi-center clinical study examining the safety and efficacy of ALA-PDD during laparoscopic examination for patients with advanced gastric cancer is currently underway in the form of doctor-initiated trials, and further verification studies will be conducted. Such imaging capability could have broad potential across cancer and vascular surgery.

Laser speckle contrast imaging and quantitative fluorescence angiography for perfusion assessment

PURPOSE

Indocyanine green fluorescence angiography (ICG-FA) is an established technique for assessment of intestinal perfusion during gastrointestinal surgery, whereas quantitative ICG-FA (q-ICG) and laser speckle contrast imaging (LSCI) are relatively unproven. The study aimed to investigate whether the techniques could be applied interchangeably for perfusion assessment.

METHODS

Nineteen pigs underwent laparotomy, two minor resections of the small bowel, and anastomoses. Additionally, seven pigs had parts of their stomach and small intestine de-vascularized. Data was also collected from an in vivo model (inferior caval vein measurements in two additional pigs) and an ex vivo flow model, allowing for standardization of experimental flow, distance, and angulation. Q-ICG and LSCI were performed, so that regions of interest were matched between the two modalities in the analyses, ensuring coverage of the same tissue.

RESULTS

The overall correlation of q-ICG and LSCI evaluated in the porcine model was modest (rho = 0.45, p < 0.001), but high in tissue with low perfusion (rho = 0.74, p < 0.001). Flux values obtained by LSCI from the ex vivo flow model revealed a decreasing flux with linearly increasing distance as well as angulation to the model. The Q-ICG perfusion values obtained varied slightly with increasing distance as well as angulation to the model.

CONCLUSIONS

Q-ICG and LSCI cannot be used interchangeably but may supplement each other. LSCI is profoundly affected by angulation and distance. In comparison, q-ICG is minimally affected by changing experimental conditions and is more readily applicable in minimally invasive surgery.

Double indocyanine green technique of robotic right colectomy: Introduction of a new technique

In robotic right hemicolectomy for colorectal cancer (CRC), appropriate lymphadenectomy and anastomotic leak prevention are critical. Visualisation of lymph nodes and blood flow with near-infrared (NIR) fluorescence DaVinci^® imaging system is a recent development. Herein, we present an improved robotic modified complete mesocolic excision (mCME) technique using indocyanine green (ICG) fluorescence. Before surgery, ICG is injected into the submucosa around the tumour with endoscopy for intraoperative detection of lymph nodes. Robotic mCME with central vascular ligation is performed, supplemented in most of the cases with selective extended lymphadenectomy. Intestinal blood flow before anastomosis is evaluated by administering ICG intravenously and NIR visualisation. Visualisation of the lymph nodes with ICG facilitates standard mCME lymphadenectomy and enables extended lymphadenectomy. Blood flow of the intestinal walls of the anastomotic site can be assessed and determines the extent of intestinal resection. Robotic double ICG technique for robotic right hemicolectomy enables improved lymphadenectomy and warrants the extent of intestinal resection; thus, becoming a strong candidate for gold standard in robotic resections of the right colon for CRC.

Chinese Herbal Medicine for Osteosarcoma in the Mouse: A Systematic Review and Meta-Analysis

OBJECTIVE

To summarize and critically assess the inhibitory effects of Chinese herbal medicine (CHM) on tumor volume and tumor weight for the treatment of osteosarcoma (OS) in mouse models.

METHODS

PubMed, Embase, Web of Science, China Knowledge Resource Integrated Database (CNKI), Wanfang Database, VIP Database, and Chinese BioMedical (CBM) were searched since their inception dates to March 10, 2016. Two reviewers independently selected the controlled studies estimating effects of CHM on mouse OS by administration in vivo. A pair-wise meta-analysis was performed. Twenty-five studies with adequate randomization were included in the systematic review.

RESULTS

CHM may significantly inhibit OS growth in mice, as assessed using the tumor weight [20 studies, n=443; 290 for CHM and 153 for the control: pooled mean difference (MD)=-2.90; 95% confidence interval (Cl): -3.50 to -2.31: P<0.01], tumor volume (16 studies, n=382; 257 for CHM and 125 for the control; pooled MD =-2.57; 95% Cl: -3.33 to -1.80; P<0.01) and tumor growth inhibition rate.

CONCLUSION

CHM could significantly inhibit the growth of OS in mouse models, which might be supportive for the design of preclinical and clinical trials in future.

Use of indocyanine green in endometriosis surgery

OBJECTIVE

To report and visually demonstrate the feasibility of using indocyanine green (ICG) in endometriosis surgery and to discuss potential benefits.

DESIGN

ICG fluorescent imaging has been validated to assess tissue perfusion with clinical use in many medical fields, including gynecology and digestive surgery, but has not described in endometriosis surgery for bowel assessment. To our knowledge, there is no validated, objective, intraoperative method to assess the vascularity of the operated bowel in endometriosis surgery, a potentially good indicator for postoperative fistula formation. Our center is conducting a registered clinical trial examining the use of ICG to evaluate the bowel vascularization after endometriosis rectal shaving surgery, and the potential role in reducing fistula rates (Institutional Review Board no 2016-002773-35).

SETTING

Tertiary university hospital.

PATIENT(S)

Three patients undergoing laparoscopic surgery for deep infiltrating endometriosis (DIE) with the use of a rectal shaving procedure.

INTERVENTIONS(S)

Patients undergoing laparoscopic surgery for DIE with a rectal shaving procedure were injected with ICG intravenously at the end of endometriosis resection.

MAIN OUTCOME MEASURES

Visual assessment of the rectal shaving area was assessed as fluoresced or not with the use of a Likert-type scale (0 = no fluorescence; 4 = very good fluorescence).

RESULT(S)

After ICG injection, all three patients have showed very good fluorescence levels at the rectal shaving area with no adverse reactions. Other uses of ICG are demonstrated throughout the video (vaginal cuff, ureter, and ovary assessment).

CONCLUSION(S)

ICG fluorescent imaging is feasible in endometriosis surgery, and there is an ongoing trial to determine if its use reduces postoperative fistula formation.

CLINICAL TRIAL REGISTRATION NUMBER

NCT03080558.

Fluorescence-guided surgery and intervention - An AAPM emerging technology blue paper

Fluorescence-guided surgery (FGS) and other interventions are rapidly evolving as a class of technologically driven interventional approaches in which many surgical specialties visualize fluorescent molecular tracers or biomarkers through associated cameras or oculars to guide clinical decisions on pathological lesion detection and excision/ablation. The technology has been commercialized for some specific applications, but also presents technical challenges unique to optical imaging that could confound the utility of some interventional procedures where real-time decisions must be made. Accordingly, the AAPM has initiated the publication of this Blue Paper of The Emerging Technology Working Group (TETAWG) and the creation of a Task Group from the Therapy Physics Committee within the Treatment Delivery Subcommittee. In describing the relevant issues, this document outlines the key parameters, stakeholders, impacts, and outcomes of clinical FGS technology and its applications. The presentation is not intended to be conclusive, but rather to inform the field of medical physics and stimulate the discussions needed in the field with respect to a seemingly low-risk imaging technology that has high potential for significant therapeutic impact. This AAPM Task Group is working toward consensus around guidelines and standards for advancing the field safely and effectively.

Feasibility of fluorescence lymph node imaging in colon cancer: FLICC

BACKGROUND

In colon cancer, appropriate tumour excision and associated lymphadenectomy directly impact recurrence and survival outcomes. Currently, there is no standard for mesenteric lymphadenectomy, with a lymph node yield of 12 acting as a surrogate quality marker. Our goal was to determine the safety and feasibility of indocyanine green (ICG) fluorescence imaging to demonstrate lymphatic drainage in colon cancer in a dose-escalation study.

METHODS

A prospective pilot study of colon cancer patients undergoing curative laparoscopic resection was performed. At surgery, peritumoural subserosal ICG injection was done to demonstrate lymphatic drainage of the tumour. A specialized fluorescence system excited the ICG and assessed lymphatics in real time. The primary outcome was the feasibility of ICG fluorescent lymphangiography for lymphatic drainage in colon cancer. Secondary outcomes were the optimal protocol for dose, injection site, and ICG lymphatic mapping timing.

RESULTS

Ten consecutive patients were evaluated (six males, mean age 69.5 years). In all, lymphatic channels were seen around the tumour to a varying extent. Eight (80%) had drainage to the sentinel node. In all cases where the lymphatic map was seen, there was no further spread 10 min after injection. In 2 patients (20%), additional lymph nodes located outside of the proposed resection margins were demonstrated. In both cases the resection was extended to include the nodes and in both patients these nodes were positive on histopathology. Factors contributing to reduced lymphatic visualization were inadequate ICG concentrations, excess India ink blocking drainage, and inflammation from tattoo placement.

CONCLUSIONS

ICG can be safely injected into the peritumoural subserosal and demonstrate lymphatic drainage in colon cancer. This proof of concept and proposed standards for the procedure can lead to future studies to optimize the application of image-guided precision surgery in colon cancer. Furthermore, this technique may be of value in indicating the need for more extended lymphadenectomy.

Fluorescence image-guided lymphadenectomy using indocyanine green and near infrared technology in robotic gastrectomy

In recent years, some researchers have tried to find a way to improve the surgical identification of the lymphatic drainage routes and lymph node stations during radical gastrectomy, thus starting a new research frontier in this field called " navigation surgery”. Among the different reported solutions, the introduction of the indocyanine green (ICG) has drawn attention for its characteristics, a fluorescence dye that can be detected in the near infrared spectral band (NIR). A fluorescence imaging technology has been integrated in the latest version of the Da Vinci robotic system and surgeons have extensively reported their experiences in colorectal and hepato-biliary surgery for tumors, vascular and lymphatic structures visualization. However, up to date, the combined use of fluorescence imaging and robotic technology has not been adequately investigated during lymphadenectomy in gastric cancer.

Intraoperative near-infrared fluorescent imaging during robotic operations

The intraoperative identification of certain anatomical structures because they are small or visually occult may be challenging. The development of minimally invasive surgery brought additional difficulties to identify these structures due to the lack of complete tactile sensitivity. A number of different forms of intraoperative mapping have been tried. Recently, the near-infrared fluorescence imaging technology with indocyanine green has been added to robotic platforms. In addition, this technology has been tested in several types of operations, and has advantages such as safety, low cost and good results. Disadvantages are linked to contrast distribution in certain clinical scenarios. The intraoperative near-infrared fluorescent imaging is new and promising addition to robotic surgery. Several reports show the utility of this technology in several different procedures. The ideal dose, time and site for dye injection are not well defined. No high quality evidence-based comparative studies and long-term follow-up outcomes have been published so far. Initial results, however, are good and safe. RESUMO A identificação intraoperatória de certas estruturas anatômicas, por seu tamanho ou por elas serem ocultas à visão, pode ser desafiadora. O desenvolvimento da cirurgia minimamente invasiva trouxe dificuldades adicionais, pela falta da sensibilidade tátil completa. Diversas formas de detecção intraoperatória destas estruturas têm sido tentadas. Recentemente, a tecnologia de fluorescência infravermelha com verde de indocianina foi associada às plataformas robóticas. Além disso, essa tecnologia tem sido testada em uma variedade de cirurgias, e suas vantagens parecem estar ligadas a baixo custo, segurança e bons resultados. As desvantagens estão associadas à má distribuição do contraste em determinados cenários. A imagem intraoperatória por fluorescência infravermelha é uma nova e promissora adição à cirurgia robótica. Diversas séries mostram a utilidade da tecnologia em diferentes procedimentos. Dose ideal, local e tempo da injeção do corante ainda não estão bem estabelecidos. Estudos comparativos de alta qualidade epidemiológica baseados em evidência ainda não estão disponíveis. No entanto, os resultados iniciais são bons e seguros.

Vision 20/20: Molecular-guided surgical oncology based upon tumor metabolism or immunologic phenotype: Technological pathways for point of care imaging and intervention

Surgical guidance with fluorescence has been demonstrated in individual clinical trials for decades, but the scientific and commercial conditions exist today for a dramatic increase in clinical value. In the past decade, increased use of indocyanine green based visualization of vascular flow, biliary function, and tissue perfusion has spawned a robust growth in commercial systems that have near-infrared emission imaging and video display capabilities. This recent history combined with major preclinical innovations in fluorescent-labeled molecular probes, has the potential for a shift in surgical practice toward resection guidance based upon molecular information in addition to conventional visual and palpable cues. Most surgical subspecialties already have treatment management decisions partially based upon the immunohistochemical phenotype of the cancer, as assessed from molecular pathology of the biopsy tissue. This phenotyping can inform the surgical resection process by spatial mapping of these features. Further integration of the diagnostic and therapeutic value of tumor metabolism sensing molecules or immune binding agents directly into the surgical process can help this field mature. Maximal value to the patient would come from identifying the spatial patterns of molecular expression in vivo that are well known to exist. However, as each molecular agent is advanced into trials, the performance of the imaging system can have a critical impact on the success. For example, use of pre-existing commercial imaging systems are not well suited to image receptor targeted fluorophores because of the lower concentrations expected, requiring orders of magnitude more sensitivity. Additionally the imaging system needs the appropriate dynamic range and image processing features to view molecular probes or therapeutics that may have nonspecific uptake or pharmacokinetic issues which lead to limitations in contrast. Imaging systems need to be chosen based upon objective performance criteria, and issues around calibration, validation, and interpretation need to be established before a clinical trial starts. Finally, as early phase trials become more established, the costs associated with failures can be crippling to the field, and so judicious use of phase 0 trials with microdose levels of agents is one viable paradigm to help the field advance, but this places high sensitivity requirements on the imaging systems used. Molecular-guided surgery has truly transformative potential, and several key challenges are outlined here with the goal of seeing efficient advancement with ideal choices. The focus of this vision 20/20 paper is on the technological aspects that are needed to be paired with these agents.

Utility of indocyanine-green fluorescent imaging during robot-assisted sphincter-saving surgery on rectal cancer patients

BACKGROUND

There have been few studies describing the use of indocyanine green (ICG) fluorescent imaging during robot-assisted (RA) sphincter-saving operations (SSOs) and assessing its potential role in reducing anastomotic leak (AL).

METHODS

A consecutive cohort of 436 rectal cancer patients who underwent curative RA SSOs were prospectively enrolled during 2010-2014, including 123 patients with ICG imaging (ICG+ group) and 313 patients without ICG imaging (ICG- group).

RESULTS

ICG imaging appeared to be helpful in identifying competent perfusion of the bowel adjacent to the anastomosis in 13 patients (10.6%) who might be susceptible to bowel ischaemia, including restrictive mesocolon. AL was remarkably greater in the ICG- group compared with the ICG+ group (5.4% vs 0.8%; p = 0.031).

CONCLUSIONS

ICG imaging during RA SSO provides accurate real-time knowledge of the perfusion status at or near the anastomosis, specifically reducing AL in patients who may incur bowel ischaemia. Copyright © 2015 John Wiley & Sons, Ltd.

Lymph Node Fluorescence During Robot-Assisted Radical Prostatectomy With Indocyanine Green: Prospective Dosing Analysis

OBJECTIVE

To prospectively assess the ideal dosing and the value of fluorescent sentinel lymph node (LN) detection with indocyanine green (ICG) for the detection of LN metastases in intermediate- and high-risk patients undergoing robot-assisted prostatectomy and extended pelvic LN dissection (ePLND).

PATIENTS AND METHODS

Twenty patients received transperineal prostatic injections of ICG. Patients were cycled through 5 doses (1.25, 2.5, 3.75, 5, and 7.5 mg) so optimal ICG dosing could be discovered early.

RESULTS

ICG injection was able to identify fluorescent LN (FLN) packets in all 20 patients. Compared to the higher ICG doses, the 1.25 and 2.5 mg doses had fewer FLN packets and were abandoned after 1 dose each. The median number of FLN packets was 4.0, 6.0, and 4.5 for the respective doses of 3.75, 5.0, and 7.5 mg. The external iliac group was the most common site of fluorescence in 27.2% of patients, followed by the common iliac (21.3%), obturator (20.3%), internal iliac (18.5%), and node of Cloquet (7.7%). Seven (35%) of 20 patients had node-positive disease. Of the 5 patients that had fluorescent tissue outside of our ePLND template, 1 had a positive node present in the anterior bladder neck fat. Across all patients, ICG had 62% sensitivity, 50% specificity, 8% positive predictive value, and 95% negative predictive value in detecting LN metastases.

CONCLUSION

The low sensitivity of ICG for the detection of LN metastases highlights why FLN dissection with ICG does not represent an alternative to ePLND.

Robotic Liver Surgery: Early Experience From a Single Surgical Center

INTRODUCTION

The use of robotic surgery in liver resection is still limited. Our aim is to present our early experience of robotic liver resection.

MATERIALS AND METHODS

It is a retrospective review of Sanchinarro University hospital experience of robotic liver resection performed from 2011 to 2014. Clinicopathologic characteristics, and perioperative and postoperative outcomes were recorded and analyzed.

RESULTS

Twenty-one procedures have been performed and 13 (65%) of them were for malignancy. There were 2 left hepatectomies, 1 right hepatectomy, 1 associated liver partition and portal vein ligation staged procedure (both steps by robotic approach), 1 bisegmentectomy and 3 segmentectomies, 9 wedge resections, and 3 pericystectomies. The mean operating time was 282 minutes (range, 90 to 540 min). Overall conversion rate and postoperative complication rate were 4.7% and 19%, respectively. The mean length of hospital stay was 13.4 days (range, 4 to 64 d).

CONCLUSION

From our early experience, robotic liver surgery is a safe and feasible procedure, especially for major hepatectomies.

The future of partial nephrectomy

Innovation in recent times has accelerated due to factors such as the globalization of communication; but there are also more barriers/safeguards in place than ever before as we strive to streamline this process. From the first planned partial nephrectomy completed in 1887, it took over a century to become recommended practice for small renal tumours. At present, identified areas for improvement/innovation are 1) to preserve renal parenchyma, 2) to optimise pre-operative eGFR and 3) to reduce global warm ischaemia time. All 3 of these, are statistically significant predictors of post-operative renal function. Urologists, have a proud history of embracing innovation & have experimented with different clamping techniques of the renal vasculature, image guidance in robotics, renal hypothermia, lasers and new robots under development. The DaVinci model may soon no longer have a monopoly on this market, as it loses its stranglehold with novel technology emerging including added features, such as haptic feedback with reduced costs. As ever, our predictions of the future may well fall wide of the mark, but in order to progress, one must open the mind to the possibilities that already exist, as evolution of existing technology often appears to be a revolution in hindsight.

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

PURPOSE

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

METHODS

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

RESULTS

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

CONCLUSION

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

Making cancer visible--Dyes in surgical oncology

Dyes share an intricate relationship with oncology. Dyes can cause cancer as chemical carcinogens, but can also be harnessed against cancer when used as diagnostic and therapeutic agents. Histopathology, imaging, and newer molecular diagnostics all rely on dyes, and their use in sentinel lymph node biopsies and intra-operative imaging has helped drive a paradigm shift in cancer surgery towards minimally-invasive and organ sparing approaches with enhanced resection accuracy. As therapeutic agents, the cytotoxicity of specific dyes can be employed in direct chemo-ablation or in photodynamic therapy. The same agent can have dual functionalities in cancer detection and treatment, in a novel field known as theranostics. This is facilitated by newer generation dyes conjugated with tumour-targeting probes such as antibodies, and these bio-conjugate agents can also incorporate nanotechnology or radio-isotopes. Further advances will be closely aligned with our increasing understanding of molecular oncology, and will form a new generation of cancer detection and treatment agents that promote precision medicine for cancer. Dyes and their roles have evolved and been reinvented, but they remain relevant as ever. This review explores the fascinating history of dyes, and their place in the state-of-the-art of oncology.

Clostridium perfringens enterotoxin C-terminal domain labeled to fluorescent dyes for in vivo visualization of micrometastatic chemotherapy-resistant ovarian cancer

Identification of micrometastatic disease at the time of surgery remains extremely challenging in ovarian cancer patients. We used fluorescence microscopy, an in vivo imaging system and a fluorescence stereo microscope to evaluate fluorescence distribution in Claudin-3- and -4-overexpressing ovarian tumors, floating tumor clumps isolated from ascites and healthy organs. To do so, mice harboring chemotherapy-naïve and chemotherapy-resistant human ovarian cancer xenografts or patient-derived xenografts (PDXs) were treated with the carboxyl-terminal binding domain of the Clostridium perfringens enterotoxin (c-CPE) conjugated to FITC (FITC-c-CPE) or the near-infrared (NIR) fluorescent tag IRDye CW800 (CW800-c-CPE) either intraperitoneally (IP) or intravenously (IV). We found tumor fluorescence to plateau at 30 min after IP injection of both the FITC-c-CPE and the CW800-c-CPE peptides and to be significantly higher than in healthy organs (p < 0.01). After IV injection of CW800-c-CPE, tumor fluorescence plateaued at 6 hr while the most favorable tumor-to-background fluorescence ratio (TBR) was found at 48 hr in both mouse models. Importantly, fluorescent c-CPE was highly sensitive for the in vivo visualization of peritoneal micrometastatic tumor implants and the identification of ovarian tumor spheroids floating in malignant ascites that were otherwise not detectable by conventional visual observation. The use of the fluorescent c-CPE peptide may represent a novel and effective optical approach at the time of primary debulking surgery for the real-time detection of micrometastatic ovarian disease overexpressing the Claudin-3 and -4 receptors or the identification of residual disease at the time of interval debulking surgery after neoadjuvant chemotherapy treatment.

Anatomical laparoscopic hepatectomy for hepatocellular carcinoma using indocyanine green fluorescence imaging

PURPOSE

It is important to minimize surgical invasiveness in the therapy of patients with hepatocellular carcinoma (HCC), and consequently laparoscopic hepatic resection is widely performed. However, most anatomical resections, except left lateral sectionectomy, remain difficult technically, and laparoscopy-assisted procedures have been introduced as an alternative approach because of the safety and curative success of the operation. We reported previously pure laparoscopic subsegmentectomy of the liver using puncture of the portal branch under percutaneous ultrasound (US) with artificial ascites. Herein, we describe pure anatomical laparoscopic segmentectomy using the puncture method with indocyanine green (ICG) injection under laparoscopic US.

PATIENTS AND METHODS

Pure laparoscopic segmentectomy was planned for 2 patients with HCC of the liver. Identification of the segment was performed by ICG injection for optical imaging using near-infrared fluorescence under laparoscopic US guidance.

RESULTS

The procedures were completed successfully, and the postoperative courses were uneventful.

CONCLUSIONS

Pure laparoscopic segmentectomy for HCC with a conventional puncture technique by ICG injection under laparoscopic US is considered to be a useful procedure featuring both low invasiveness and curative success.

An update on laparoscopic liver resection: The French Hepato-Bilio-Pancreatic Surgery Association statement

Laparoscopic liver resection has been recognized as a safe and efficient approach since the Louisville Conference in 2008, but its use still remains confined to experienced teams in specialized centers, and may lack some standardization. The 2013 Session of French Association for Hepatobiliary and Pancreatic Surgery (ACHBT) specifically focused on laparoscopic liver surgery and the particular aspects and issues arising since the 2008 conference. Our objective is to provide an update and summarize the current French position on laparoscopic liver surgery. An overview of the current practice of laparoscopic liver resections in France since 2008 is presented. The issues surrounding standardization for left lateral sectionectomy and right hepatectomy, hybrid and hand-assisted techniques are raised and discussed. Finally, future technologies and technical perspectives are outlined.

Minimally invasive pancreatectomy for cancer: a critical review of the current literature

Minimally invasive surgery (MIS) has transformed operative practices by offering patients procedures with reduced hospital stay and recovery compared to that of open operations. In spite of the advantages of a MIS approach, the application to pancreatectomy has only recently emerged. This review aims to analyze and discuss available comparative studies as they relate to resection techniques for treatment of malignant disease. A PubMed search was used to obtain original studies and meta-analyses relating to MIS pancreatectomy from 2008 to 2013. Several studies were identified that reported on the application of MIS specifically to the treatment of cancer, many of which were retrospective, single-institution studies. Notwithstanding an inherent selection bias, several studies suggest that MIS can provide equivalent R0 resection rates, number of lymph nodes harvested, and survival to that of open resection. Furthermore, parameters such as blood loss and length of stay are significantly reduced in patients treated with MIS. The current literature supports the conclusion that MIS is safe and effective as a treatment for cancer in well-selected patients in the hands of experienced surgeons. However, the published studies to date are observational in nature and therefore higher quality studies will be needed to support the application and generalizability of MIS in the treatment of pancreatic malignancies.

Near-infrared imaging of brain tumors using the Tumor Paint BLZ-100 to achieve near-complete resection of brain tumors

OBJECT

The intraoperative clear delineation between brain tumor and normal tissue in real time is required to ensure near-complete resection without damaging the nearby eloquent brain. Tumor Paint BLZ-100, a tumor ligand chlorotoxin (CTX) conjugated to indocyanine green (ICG), has shown potential to be a targeted contrast agent. There are many infrared imaging systems in use, but they are not optimized to the low concentration and amount of ICG. The authors present a novel proof-of-concept near-infrared (NIR) imaging system using a standard charge-coupled device (CCD) camera for visualizing low levels of ICG attached to the tumors. This system is small, inexpensive, and sensitive. The imaging system uses a narrow-band laser at 785 nm and a notch filter in front of the sensor at the band. The camera is a 2-CCD camera, which uses identical CCDs for both visible and NIR light.

METHODS

The NIR system is tested with serial dilution of BLZ-100 from 1 μM to 50 pM in 5% Intralipid solution while the excitation energy is varied from 5 to 40 mW/cm(2). The analog gain of the CCD was changed from 0, 6, and 12 dB to determine the signal-to-noise ratio. In addition to the Intralipid solution, BLZ-100 was injected 48 hours before euthanizing the mice that were implanted with the human glioma cell line. The brain was removed and imaged using the NIR imaging system.

RESULTS

The authors' results show that the NIR imaging system using a standard CCD is able to visualize the ICG down to 50 nM of concentration with a high signal-to-noise ratio. The preliminary experiment on human glioma implanted in mouse brains demonstrated that BLZ-100 has a high affinity for glioma compared with normal brain tissue. Additionally, the results show that NIR excitation is able to penetrate deeply and has a potential to visualize metastatic lesions that are separate from the main tumor.

CONCLUSIONS

The authors have seen that BLZ-100 has a very high affinity toward human gliomas. They also describe a small, cost-effective, and sensitive NIR system for visualizing brain tumors tagged using BLZ-100. The authors hope that the use of BLZ-100 along with NIR imaging will be useful to delineate the brain tumors in real time and assist surgeons in near-complete tumor removal to increase survival and reduce neurological deficits.

Intraoperative optical imaging and tissue interrogation during urologic surgery

PURPOSE OF REVIEW

To review optical imaging technologies in urologic surgery aimed to facilitate intraoperative imaging and tissue interrogation.

RECENT FINDINGS

Emerging new optical imaging technologies can be integrated in the operating room environment during minimally invasive and open surgery. These technologies include macroscopic fluorescence imaging that provides contrast enhancement between normal and diseased tissue and microscopic imaging that provides tissue characterization.

SUMMARY

Optical imaging technologies that have reached the clinical arena in urologic surgery were reviewed, including photodynamic diagnosis, near infrared fluorescence imaging, optical coherence tomography, and confocal laser endomicroscopy.

Robotic-assisted microsurgery for an elective microsurgical practice

Robotic-assisted microsurgery can be utilized for either intracorporal or extracorporeal surgical procedures. Three-dimensional high-definition magnification, a stable ergonomic platform, elimination of physiologic tremor, and motion scaling make the robotic platform attractive for microsurgeons for complex procedures. Additionally, robotic assistance enables the microsurgeon to take microsurgery to challenging intracorporeal locations in a minimally invasive manner. Recent adjunctive technological developments offer the robotic platform enhanced optical magnification, improved intraoperative imaging, and more precise ablation techniques for microsurgical procedures. The authors present the current state-of-the art tools available in the robotic-assisted microsurgical platform.

Robotic versus open gastrectomy for gastric cancer: a meta-analysis

Aim

To evaluate the safety and efficacy of robotic gastrectomy versus open gastrectomy for gastric cancer.

Methods

A comprehensive search of PubMed, EMBASE, Cochrane Library, and Web of Knowledge was performed. Systematic review was carried out to identify studies comparing robotic gastrectomy and open gastrectomy in gastric cancer. Intraoperative and postoperative outcomes were also analyzed to evaluate the safety and efficacy of the surgery. A fixed effects model or a random effects model was utilized according to the heterogeneity.

Results

Four studies involving 5780 patients with 520 (9.00%) cases of robotic gastrectomy and 5260 (91.00%) cases of open gastrectomy were included in this meta-analysis. Compared to open gastrectomy, robotic gastrectomy has a significantly longer operation time (weighted mean differences (WMD) =92.37, 95% confidence interval (CI): 55.63 to 129.12, P<0.00001), lower blood loss (WMD: -126.08, 95% CI: -189.02 to -63.13, P<0.0001), and shorter hospital stay (WMD = -2.87; 95% CI: -4.17 to -1.56; P<0.0001). No statistical difference was noted based on the rate of overall postoperative complication, wound infection, bleeding, number of harvested lymph nodes, anastomotic leakage and postoperative mortality rate.

Conclusions

The results of this meta-analysis suggest that robotic gastrectomy is a better alternative technique to open gastrectomy for gastric cancer. However, more prospective, well-designed, multicenter, randomized controlled trials are necessary to further evaluate the safety and efficacy as well as the long-term outcome.