Diagnostic value of sentinel lymph node biopsy in gastric cancer: a meta-analysis

[Fluorescence lymphoscopy with sentinel lymph node biopsy in research of lymphatic flow in early gastric cancer]

OBJECTIVE

To analyze the incidence and risk factors of regional lymph node metastatic lesions, as well as patterns of lymphatic drainage in early gastric cancer using indocyanine green (ICG).

MATERIAL AND METHODS

A prospective single-center non-randomized study included 67 patients with early gastric cancer between 2016 and 2019. All patients underwent endoscopic dissection or surgical resection with sentinel lymph node biopsy.

RESULTS

Regional lymph node metastatic lesions were detected in 12 (20.2%) out of 59 patients with examined lymph nodes. Of these, 11 out of 12 patients had sentinel lymph node lesion, and only 1 patient had metastasis outside this lymph node. The proposed technique for sentinel lymph node biopsy demonstrated high sensitivity, specificity and accuracy (93.2%, 100% and 98.3%, respectively). Risk factors for metastasis of early gastric cancer to regional lymph nodes were high grade adenocarcinoma (p=0.038) and tumor of anterior gastric wall (p=0.013). All patients with tumors of the upper third of the stomach had sentinel lymph node in the left gastric artery basin. Lymph flow was multidirectional in patients with tumors of the middle third of the stomach. In tumors of the lower third of the stomach, sentinel lymph node was located in the right gastroepiploic artery (50%) and left gastric artery basins (36.84%) (p=0.002). Sentinel lymph node was located in the left gastric artery basin in 84% of patients with tumors of the lesser curvature (p<0.001). Lymphatic drainage was multidirectional if tumors were localized on anterior and posterior walls, as well as on the greater curvature.

CONCLUSION

The proposed technique for sentinel lymph node biopsy demonstrated high sensitivity, specificity and accuracy (93.2%, 100% and 98.3%, respectively). ICG is valuable to identify the first lymph node in lymphatic drainage pathway in 83.6% of cases that makes it possible to assess the regional lymphatic collector. In addition, sentinel lymph node biopsy with ICG contributes to analysis of lymphatic drainage in early gastric cancer. The last one has both scientific and practical significance.

Lymph node mapping with ICG near-infrared fluorescence imaging: technique and results

PURPOSE

Lymphadenectomy represents a fundamental step during gastrointestinal cancer resection, as the removal of an adequate number of lymph nodes is crucial to define the stage of the disease and prognosis. Lymphadenectomy during gastric and colorectal resection and adrenalectomy for cancer are technically demanding and can be associated with risk of bleeding. To date, lymphadenectomy is often performed without any visual aid. Indocyanine green fluorescence for lymph node mapping can provide better intraoperative visualization. The purpose of this review is to report the current evidence on this topic.

MATERIALS AND METHODS

A systematic research of the electronic databases Medline, Embase and Google Scholar was conducted from the inception to December 2022.

RESULTS

This review summarizes the current evidence of techniques and results of fluorescence guided lymphatic mapping during gastrointestinal and adrenal surgery.

CONCLUSION

According to this review, ICG guided lymphadenectomy for gastrointestinal tumours and adrenocortical carcinoma is feasible and safe. In gastrointestinal tumours it allows higher number of harvested lymph nodes.

Endoscopic Resection of Early Gastric Cancer and Pre-Malignant Gastric Lesions

Early gastric cancer comprises gastric malignancies that are confined to the mucosa or submucosa, irrespective of lymph node metastasis. Endoscopic resection is currently pivotal for the management of such early lesions, and it is the recommended treatment for tumors presenting a very low risk of lymph node metastasis. In general, these lesions consist of two groups of differentiated mucosal adenocarcinomas: non-ulcerated lesions (regardless of their size) and small ulcerated lesions. Endoscopic submucosal dissection is the technique of choice in most cases. This procedure has high rates of complete histological resection while maintaining gastric anatomy and its functions, resulting in fewer adverse events than surgery and having a lesser impact on patient-reported quality of life. Nonetheless, approximately 20% of resected lesions do not fulfill curative criteria and demand further treatment, highlighting the importance of patient selection. Additionally, the preservation of the stomach results in a moderate risk of metachronous lesions, which underlines the need for surveillance. We review the current evidence regarding the endoscopic treatment of early gastric cancer, including the short-and long-term results and management after resection.

Preclinical evaluation of sentinel node localization in the stomach via mannose-labelled magnetic nanoparticles and indocyanine green

BACKGROUND

Gastrectomy with extended (D2) lymphadenectomy is considered standard of care for gastric cancer to provide the best possible outcomes and pathologic staging. However, D2 gastrectomy is a technically demanding operation and reported to be associated with increased complications and mortality. Application of sentinel lymph node (SLN) concept in gastric cancer has the potential to reduce patient morbidity; however, SLN techniques are not established for gastrectomy, in part due to lack of practical tracers. An effective and convenient tracer with enhanced SLN accumulation is critically needed.

METHODS

Mannose-labelled magnetic tracer 'FerroTrace' and fluorescent dye indocyanine green (ICG) were injected laparoscopically into the stomach submucosa of 8 healthy swine under general anaesthesia. Intraoperative fluorescence imaging was used to highlight draining lymphatic pathways containing ICG, while preoperative T2-weighted MRI and ex vivo magnetometer probe measurements were used to identify nodes containing FerroTrace. Lymphadenectomy was performed either robotically (n = 2) or via laparotomy (n = 6).

RESULTS

Mixing ICG and FerroTrace ensured concurrence of fluorescent and magnetic signals in SLNs. An initial trial with robotic dissection removed all magnetic LNs (n = 4). In the subsequent laparotomy study that targeted all ICG-LNs based on intraoperative fluorescence imaging, dissection removed an average of 4.7 ± 1.2 fluorescent, and 2.0 ± 1.3 magnetic LNs per animal. Both MRI and magnetometer detected 100% of SLNs (n = 7). FerroTrace demonstrated high specificity to SLNs, which contained 76 ± 30% of total lymphotropic iron, and 88 ± 20 % of the overall magnetometer signal.

CONCLUSIONS

Through utilisation of this dual tracer approach, SLNs were identified via preoperative MRI, visualised intraoperatively with fluorescence imaging, and confirmed with a magnetometer. This combination pairs the sensitivity of ICG with SLN-specific FerroTrace and can be used for reliable SLN detection in gastric cancer, with potential applications in neoadjuvant therapy.

Application of indocyanine green (ICG)-guided surgery in clinical practice: lesson to learn from other organs-an overview on clinical applications and future perspectives

Indocyanine green (ICG) fluorescence-guided surgery is a modality of intra-operative navigation that might support the surgeon with enhanced visualization of anatomical structures in real time. Over the last years, it has emerged as one of the most promising and rapidly developing technical innovations in surgery. The most popular current clinical applications include fluorescence cholangiography, bowel anastomotic perfusion assessment, fluorescence-guided lymphography for sentinel lymph-node identification and guided lymphadenectomy and the possible use in oncological surgery for the identification and localization of tumors and the diagnosis and treatment of peritoneal carcinosis. This paper provides an overview of the multiple fields of applications of ICG fluorescence-guided surgery in visceral and oncological surgery, discussing indications summarizing most recent and significative available literature and giving technical notes of use.

Early Gastric Cancer: Update on Prevention, Diagnosis and Treatment

Gastric cancer (GC) is a relevant public health issue as its incidence and mortality rates are growing worldwide. There are recognized carcinogen agents, such as obesity, tobacco, meat, alcohol consumption and some dietary protective factors. Strategies of early diagnosis through population-based surveillance programs have been demonstrated to be effective in lowering the morbidity and mortality related to GC in some countries. Indeed, the detection of early lesions is very important in order to offer minimally invasive treatments. Endoscopic resection is the gold standard for lesions with a low risk of lymph node metastasis, whereas surgical mini-invasive approaches can be considered in early lesions when endoscopy is not curative. This review outlines the role of lifestyle and prevention strategies for GC, in order to reduce the patients' risk factors, implement the surveillance of precancerous conditions and, therefore, improve the diagnosis of early lesions. Furthermore, we summarize the available treatments for early gastric cancer.

Recent Advances in Sentinel Node Navigation Surgery for Early Gastric Cancer

Maintaining the postoperative quality of life (QOL) while ensuring curability without overtreatment is important in the treatment of early gastric cancer. Postoperative QOL is anticipated to be maintained through minimally invasive function-preserving gastrectomy in early gastric cancer. The concept of the sentinel lymph node (SN) basin is essential to maintain the curability of early gastric cancer using minimally invasive function-preserving gastrectomy. However, additional resection after surgery is difficult to perform in gastric cancer. Thus, the SN basin theory is important. Recently, a multicenter randomized phase III trial in South Korea (SENORITA trial) proved that laparoscopic sentinel node navigation surgery (LSNNS) for stomach preservation results in better postoperative QOL compared with standard gastrectomy in patients with early gastric cancer. LSNNS contributes to patients' QOL based on the concept that curability is not impaired. A multicenter nonrandomized phase III trial is ongoing in Japan, and oncologic safety is expected to be demonstrated. LSNNS has been established as a treatment option for selected patients with early gastric cancer, and its application will become widespread in the future.

Korean Practice Guidelines for Gastric Cancer 2022: An Evidence-based, Multidisciplinary Approach

Gastric cancer is one of the most common cancers in Korea and the world. Since 2004, this is the 4th gastric cancer guideline published in Korea which is the revised version of previous evidence-based approach in 2018. Current guideline is a collaborative work of the interdisciplinary working group including experts in the field of gastric surgery, gastroenterology, endoscopy, medical oncology, abdominal radiology, pathology, nuclear medicine, radiation oncology and guideline development methodology. Total of 33 key questions were updated or proposed after a collaborative review by the working group and 40 statements were developed according to the systematic review using the MEDLINE, Embase, Cochrane Library and KoreaMed database. The level of evidence and the grading of recommendations were categorized according to the Grading of Recommendations, Assessment, Development and Evaluation proposition. Evidence level, benefit, harm, and clinical applicability was considered as the significant factors for recommendation. The working group reviewed recommendations and discussed for consensus. In the earlier part, general consideration discusses screening, diagnosis and staging of endoscopy, pathology, radiology, and nuclear medicine. Flowchart is depicted with statements which is supported by meta-analysis and references. Since clinical trial and systematic review was not suitable for postoperative oncologic and nutritional follow-up, working group agreed to conduct a nationwide survey investigating the clinical practice of all tertiary or general hospitals in Korea. The purpose of this survey was to provide baseline information on follow up. Herein we present a multidisciplinary-evidence based gastric cancer guideline.

Ingenuity and tips for laparoscopic local resection for local recurrence of early gastric cancer after endoscopic submucosal dissection: A case report

Introduction and importance

The presence of severe comorbidities is associated with poor surgical outcomes in patients who undergo curative resection for gastric cancer. Herein, we present a report of laparoscopic local resection (LLR) for the local recurrence of gastric cancer in a patient with severe comorbidities.

Case presentation

A 73-year-old man underwent endoscopic submucosal dissection (ESD) for an early gastric cancer located at the greater curvature of the gastric antrum. One year after the ESD, follow-up gastroscopy revealed a local recurrence.

Clinical discussion

LLR was performed owing to severe comorbidities such as chronic heart failure, severe chronic obstructive pulmonary disease, and diabetes mellitus. We confirmed the location of the tumor with an endoscope, and full-thickness stitches were placed outside the tumor to prevent displacement between the submucosal and serosal muscular layers. Full-thickness resection of the stomach wall was performed along the stitch points using an ultrasonic shear. The edge of the resection line was closed using a laparoscopic stapling system. The patient had an uneventful postoperative course and was discharged 8 days after the operation. The patient had no disease recurrence and late complications such as digestive symptom and weight loss at the 9-month follow-up after the operation.

Conclusion

LLR might be a suitable treatment option for high-risk patients with gastric cancer. During full-thickness resection of the stomach wall, our method enables the maintenance of a negative margin without the need for ESD.

•

A case of local resection for gastric cancer in a patient with severe comorbidities

•

Ingenuity and tips of laparoscopic local resection without demanding ESD

•

The method of laparoscopic local resection to maintain a negative margin

Laparoscopic Sentinel Node Navigation Surgery for Stomach Preservation in Patients With Early Gastric Cancer: A Randomized Clinical Trial

PURPOSE

To compare postoperative complications, long-term survival, and quality of life (QOL) after laparoscopic sentinel node navigation surgery (LSNNS) and laparoscopic standard gastrectomy (LSG).

METHODS

Five hundred eighty patients with preoperatively diagnosed stage IA gastric adenocarcinoma (≤ 3 cm) were assigned to undergo either LSG or LSNNS. Observers were not blinded to patient grouping. The primary outcome was 3-year disease-free survival (3y-DFS). Secondary outcomes included postoperative complications, QOL, 3-year disease-specific survival (3y-DSS), and 3-year overall survival (3y-OS).

RESULTS

In total, 527 patients were included in the modified intention-to-treat analysis population for the primary outcome (LSG, 269; LSNNS, 258). Stomach-preserving surgery was performed in 210 patients (81%) in the LSNNS group. During the median follow-up duration, the 3y-DFS rates in the LSG and LSNNS groups were 95.5% and 91.8%, respectively (difference: 3.7%; 95% CI, -0.6 to 8.1). Three patients with recurrence and five with metachronous gastric cancer in the LSNNS group underwent standard surgery. Two patients with distant metastasis in both groups were treated with palliative chemotherapy. The 3y-DSS and 3y-OS rates in the LSG and LSNNS groups were 99.5% and 99.1% (P = .59) and 99.2% and 97.6% (P = .17), respectively. Postoperative complications occurred in 19.0% of the LSG group and 15.5% of the LSNNS group (P = .294). The LSNNS group showed better physical function (P = .015), less symptoms (P < .001), and improved nutrition than the LSG group.

CONCLUSION

LSNNS did not show noninferiority to LSG for 3y-DFS, with a 5% margin. However, the 3y-DSS and 3y-OS were not different after rescue surgery in cases of recurrence/metachronous gastric cancer, and LSNNS had better long-term QOL and nutrition than LSG.

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.

Function-Preserving Gastrectomy for Early Gastric Cancer

Simple Summary

For patients with early gastric cancer (EGC), a good prognosis is achieved by conventional standard gastrectomy with radical lymphadenectomy. However, postgastrectomy syndrome is often inevitable and results in decreased quality of life (QOL). To improve patients’ QOL, proximal gastrectomy instead of total gastrectomy and pylorus-preserving gastrectomy instead of distal gastrectomy have been widely accepted as function-preserving gastrectomies. Recently, personalized, minimized gastrectomy with sentinel node navigation surgery has been developed and is expected to be an ideal treatment option for patients with EGC. Herein, we review the indications, surgical techniques, and postoperative outcomes of function-preserving gastrectomy.

Abstract

Recently, minimally invasive (endoscopic or laparoscopic) treatment for early gastric cancer (EGC) has been widely accepted. However, a standard gastrectomy with radical lymphadenectomy is generally performed in patients with EGC who have no indications for endoscopic resection, and postgastrectomy dysfunction is one of the problems of standard gastrectomy. Function-preserving gastrectomy, such as proximal gastrectomy and pylorus-preserving gastrectomy, can be considered when attempting to preserve the patient’s quality of life (QOL) postoperatively. In addition, sentinel node navigation surgery for EGC has been applied in clinical practice in several prospective studies on function-preserving personalized minimized gastrectomy. In the near future, the sentinel lymph node concept is expected to form the basis for establishing an ideal, personalized, minimally invasive function-preserving treatment for patients with EGC, which will improve their postoperative QOL without compromising their long-term survival. In this review article, we summarize the current status, surgical techniques, and postoperative outcomes of function-preserving gastrectomy for EGC.

Pathologic Lymph Node Staging of Gastric Cancer

OBJECTIVES

The TNM classification is the main tool for lymph node (LN) staging in gastric cancer (GC). However, alternative LN staging systems have been proposed, and the role of features other than the number of metastatic LNs is being investigated. Our aim is to discuss the main challenges of LN assessment in GC.

METHODS

Comprehensive review of the literature on alternative LN staging systems, examined LNs, sentinel LN (SLN) biopsy, LN micrometastases (LNMIs), extracapsular extension (ECE), and tumor deposits (TDs) in GC.

RESULTS

Many controversies exist regarding LN assessment in GC. The TNM classification shows excellent prognostic performance, but alternative prognostic methods such as the LN ratio or log odds of positive LNs have demonstrated to be better than the TNM system in terms of prognostic accuracy. The value of SLN biopsy and LNMIs in GC is still unclear, and several challenges concerning their clinical impact and pathologic analysis must be overcome before their introduction in clinical practice. Most authors have identified ECE and TDs as independent prognostic factors for survival in GC.

CONCLUSIONS

Further studies should be performed to evaluate the impact of these features on the TNM classification and patient outcomes, as well as to standardize alternative LN staging systems.

Endoscopic diagnosis and treatment of gastric dysplasia and early cancer: Current evidence and what the future may hold

Gastric cancer accounts for a significant proportion of worldwide cancer-related morbidity and mortality. The well documented precancerous cascade provides an opportunity for clinicians to detect and treat gastric cancers at an endoscopically curable stage. In high prevalence regions such as Japan and Korea, this has led to the implementation of population screening programs. However, guidelines remain ambiguous in lower prevalence regions. In recent years, there have been many advances in the endoscopic diagnosis and treatment of early gastric cancer and precancerous lesions. More advanced endoscopic imaging has led to improved detection and characterization of gastric lesions as well as superior accuracy for delineation of margins prior to resection. In addition, promising early data on artificial intelligence in gastroscopy suggests a future role for this technology in maximizing the yield of advanced endoscopic imaging. Data on endoscopic resection (ER) are particularly robust in Japan and Korea, with high rates of curative ER and markedly reduced procedural morbidity. However, there is a shortage of data in other regions to support the applicability of protocols from these high prevalence countries. Future advances in endoscopic therapeutics will likely lead to further expansion of the current indications for ER, as both technology and proceduralist expertise continue to grow.

Surgical Treatment for Gastric Cancer

Surgery is an essential component of curative-intent treatment strategies for gastric cancer. However, the care of each patient with gastric cancer must be individualized based on patient and tumor characteristics. It is important that all physicians who will be caring for patient with gastric cancer understand the current best practices of surgical management to provide patients with the highest quality of care. This article aims to provide this information while acknowledging areas of surgical management that are still controversial.

How useful is sentinel lymph node biopsy for the status of lymph node metastasis in cT1N0M0 gastric cancer? A systematic review and meta-analysis

Sentinel lymph node biopsy (SLNB) is intriguing because it is expected to further expand the indication of endoscopic resection (ER) for cT1N0M0 gastric cancer and as an additional operation for post-ER gastric cancer. The aim of our study was to perform a systematic review and meta-analysis on the feasibility and diagnostic value of SLNB technique in patients with cT1N0M0 gastric cancer. Eligible studies were systematically searched in PubMed, Embase, and Cochrane Library databases from inception to April 2020. A random-effect model was used to pool the data, and subgroup analysis was used to explain the heterogeneities. A total of 22 clinical studies (1993 patients with cT1N0M0 gastric cancer) were included. The pooled SLN identification rate, sensitivity, specificity, and diagnostic odds ratio with 95% confidence intervals were 0.99 (0.99-1.00), 0.92 (0.88-0.95), 1.00 (1.00-1.00), and 832.8 (395.5-1753.6), respectively. The summary receiver operator characteristic displayed a test accuracy of 99.3%. Subgroup analysis found an improved SLN sensitivity for studies with the mean number of SLNs > 4 and studies stained with a combination of hematoxylin-eosin with immunohistochemistry (HE + IHC). Further, studies using the basin dissection were associated with a higher SLN identification rate. The current meta-analysis provides data that favors the use of SLNB for predicting the status of lymph node metastasis in patients with cT1N0M0 gastric cancer. However, establishing standard procedure and suitable criteria for further application and optimization of SLNB is urgently needed.

Lymph Node Mapping in Gastric Cancer Surgery: Current Status and New Horizons

Gastric cancer (GC) remains one of the most important malignant diseases with significant geographical, ethnic, and socioeconomic differences in distribution. Sentinel lymph node (SLN) mapping is an accepted way to assess lymphatic spread in several solid tumors; however, the complexity of gastric lymphatic drainage may discourage use of this procedure, and the estimated accuracy rate is, in general, reasonably good. This study aimed at reviewing the current status of SLN mapping and navigation surgery in GC. SLN mapping should be limited to tumors clinically T1 and less than 4 cm in diameter. Combination SLN mapping with radioactive colloid and blue dye is used as the standard. Despite its notable limitations, SLN mapping and SLN navigation surgery present a novelty individualizing the extent of lymphadenectomy.

Sentinel node mapping for post-endoscopic resection gastric cancer: multicenter retrospective cohort study in Japan

BACKGROUND

Standard gastrectomy with systematic lymphadenectomy as an additional surgery after endoscopic resection (ER) causes a deterioration in long-term quality of life. If the sentinel lymph node (SN) basin concept can be applied in post-ER gastric cancer, minimal surgery can be applied without reducing the curability. This retrospective multicenter cohort study aimed to verify the validity of the SN basin concept in post-ER gastric cancer.

PATIENTS AND METHODS

Individual data of 132 patients who underwent SN mapping after ER were collected from 8 university hospitals in Japan from 2001 to 2016. Tracers were injected endoscopically in the submucosal layer at four sites around the post-ER scar. We compared the SN basin distribution of post-ER gastric cancer with that of 275 patients with non-ER gastric cancer.

RESULTS

Two cases of SN were unidentified, both involving a single tracer (SN detection rate: 98.5%). Nine cases (6.8%) of lymph node metastasis were found, of which eight had a metastatic lymph node within the SNs and one had a non-SN metastasis within the SN basin. The diagnostic sensitivity of SN mapping for lymph node metastasis was 88.9% in post-ER group and 95.7% in non-ER group (P = 0.490); the accuracy was 99.2% and 99.6% (P = 0.539), respectively. Regarding the SN basin, no significant intergroup differences were found regardless of the primary tumor location.

CONCLUSIONS

Our findings clarified the feasibility of SN mapping based on the SN basin concept in patients with gastric cancer who previously underwent ER.

Burgeoning study of sentinel-node analysis on management of early gastric cancer after endoscopic submucosal dissection

Endoscopic submucosal dissection (ESD) represents an organ-preserving alternative to surgical resection of early gastric cancer. However, even with ESD yielding en-bloc resection specimens, there are concerns regarding tumor spread such as with larger lesions, ulcerated lesions, undifferentiated pathology and submucosal invasion. Sentinel node navigational surgery (SNNS) when combined with ESD offers a minimally invasive alternative to the traditional extended gastrectomy and lymphadenectomy if lack of lymph node spread can be confirmed. This would have a clear advantage in terms of potential complications and quality of life. However, SNNS, though useful in other malignancies such as breast cancer and melanoma, may not have a sufficient sensitivity for malignancy and negative predictive value in EGC to justify this as standard practice after ESD. The results of SNNS may improve with greater standardization and more involved dissection, technological innovations and more experience and validation such that the paradigm for post-ESD resection of EGC may change and include SNNS.

Sentinel lymph node detection for gastric cancer: Promise or pitfall?

At present, optimal surgery for gastric cancer is still under debate, especially the extent of lymph node dissection. Gastrectomy with D1/D2 lymphadenectomy is standard treatment for resectable advanced gastric cancer. However, in early gastric cancer without lymph node metastasis, gastrectomy with D1/D2 lymphadenectomy may not be unnecessary, which could increases morbidity and mortality and reduces the quality of life (QOL). Therefore, the concept of sentinel lymph node could be applied in gastric cancer. But due to the complexity of gastric lymphatic drainage, there are still many issues under debate, such as suitable tracers, the method of mapping and collecting and the oncologic safety of sentinel node navigation surgery (SNNS). In addition, skip metastasis and unreliability of intraoperative pathological diagnosis are two main reasons for false negative cases. In this review, we summarize the current status and controversy of sentinel lymph node detection in gastric cancer, attempting to help with practical application. Further, we hold opinion that we should be cautious about performing sentinel lymph node detection in gastric cancer before an accurate and effective method occurs.

The Application of Spleen-Preserving Splenic Regional Laparoscopic Lymphadenectomy with Spleen Kept In Situ and Laparotomy with Spleen Lifted Out of the Abdomen for Locally Advanced Proximal Gastric Cancer: A Retrospective Study

Background and Purpose

Findings whether laparoscopic lymphadenectomy with spleen kept in situ or laparotomy with spleen lifted out of the abdomen is more effective remain inconclusive. This study is aimed at comparing outcomes of spleen-preserving splenic regional laparoscopic lymphadenectomy with spleen kept in situ versus laparotomy with spleen lifted out of the abdomen for locally advanced proximal gastric cancer.

Methods

Data from patients with locally advanced proximal gastric cancer were collected from January 2011 to January 2014. A total of 246 patients were identified who received D2 radical total gastrectomy together with spleen-preserving splenic regional lymphadenectomy. Of those patients, 87 patients underwent laparoscopic splenic regional lymphadenectomy with spleen kept in situ (LSKS-SRLA) and 159 patients underwent laparotomy with spleen lifted out of the abdomen (LSLA-SRLA). Surgical outcomes and long-term outcomes were compared between the two groups.

Results

The total number of lymph node dissection, intraoperative blood loss volume, intraoperative injury cases, and postoperative complications had no statistically significant difference between the two groups. The number of splenic regional lymph node dissections was 3.90 ± 1.05 per case in the LSLA-SRLA group and 2.89 ± 1.04 in the LSKS-SRLA group. The operation time, length of the incision, and hospital days were shorter in the LSKS-SRLA group. The total recurrence and metastatic rates and 3-year cumulative survival rate had no statistically significant difference between the two groups.

Conclusions

Similar long-term outcomes were achieved in the LSKS-SRLA and LSLA-SRLA groups for locally advanced proximal gastric cancer. However, in the aspects of surgical time, length of incision, and postoperative recovery, the LSKS-SRLA group had obvious advantages.

111In-labeled anti-cadherin17 antibody D2101 has potential as a noninvasive imaging probe for diagnosing gastric cancer and lymph-node metastasis

OBJECTIVE

Cadherin-17 (CDH17) is a transmembrane protein that mediates cell-cell adhesion and is frequently expressed in adenocarcinomas, including gastric cancer. CDH17 may be an effective diagnostic marker for the staging of gastric cancer. Here, we developed an ¹¹¹In-labeled anti-CDH17 monoclonal antibody (Mab) as an imaging tracer and performed biodistribution and single-photon emission computed tomography (SPECT)/computed tomography (CT) imaging studies using mice with CDH17-positive gastric cancer xenografts. CDH17 expression in gastric cancer specimens was also analyzed.

METHODS

The cross-reactivity and affinity of our anti-CDH17 Mab D2101 was evaluated by surface plasmon resonance analysis and cell enzyme-linked immunosorbent assay, respectively. Biodistribution and SPECT/CT studies of ¹¹¹In-labeled D2101 (¹¹¹In-D2101) were performed. CDH17 expression in gastric cancer specimens was evaluated by immunohistochemistry.

RESULTS

Surface plasmon resonance analysis revealed that D2101 specifically recognizes human CDH17, but not murine CDH17. The affinity of D2101 slightly decreased as a result of the radiolabeling procedures. The biodistribution study revealed high uptake of ¹¹¹In-D2101 in tumors (maximum, 39.2 ± 9.5% ID/g at 96 h postinjection), but low uptake in normal organs, including the stomach. Temporal SPECT/CT imaging with ¹¹¹In-D2101 visualized tumors with a high degree of tumor-to-nontumor contrast. Immunohistochemical analysis revealed that, compared with HER2, which is a potential marker of N-stage, CDH17 had a higher frequency of positivity in specimens of primary and metastatic gastric cancer.

CONCLUSION

Our ¹¹¹In-anti-CDH17 Mab D2101 depicted CDH17-positive gastric cancer xenografts in vivo and has the potential to be an imaging probe for the diagnosis of primary lesions and lymph-node metastasis in gastric cancer.

Sentinel Node Navigation in Gastric Cancer: Where Do We Stand?

BACKGROUND

Early gastric cancer (EGC) is more common nowadays and is related a to low percentage of lymph node metastasis. For this reason, there is enormous interest to implicate minimally invasive approaches. Recently, special efforts have been made towards a potential intraoperative (real-time) lymph node metastasis (LNM) assessment, as nodal disease status could not be identified with precision before or during surgery. In this direction, accurate prediction of the LNM status through sentinel LN mapping has been attempted, as an approach to the intraoperative detection of sentinel lymph nodes (SLNs). A careful literature search was conducted in order to clarify the potential clinical application of SN biopsy in the gastric cancer field.

CONCLUSION

The real clinical application of SN biopsy in gastric cancer treatment has been more than challenging due to the "complicated" nature of gastric lymphatic drainage and the high possibility of "skip" metastasis phenomenon. Notably, sophisticated technical aspects, such as the preferred tracer used and the potential "ideal" method to verify the presence of metastases in the resected SLNs, made SN biopsy application in gastric cancer field extremely demanding. Assessing the potential role of SN navigation for gastric cancer treatment in the era of advanced technology, where the minimally invasive surgical approaches are in the top of the scientific interest, it has to be highlighted that SN navigation for gastric cancer is a topic that remains highly controversial, and the need for future clinical trials on this topic is obvious.

Nonselective Lymph Node Dissection and Sentinel Lymph Node Mapping and Biopsy

Clinical staging is important for determining the extent of disease in animals with malignant cancers. The status of the lymph node will help determine whether adjuvant treatment is indicated. Historically, the regional anatomic lymph node has been sampled to determine the presence or absence of metastatic disease, but there is increasing evidence that the regional anatomic lymph node is often different to the sentinel lymph node. As a result, several sentinel lymph node mapping techniques have been described for more accurate clinical staging of oncologic patients.

Prospective Multicenter Feasibility Study of Laparoscopic Sentinel Basin Dissection after Endoscopic Submucosal Dissection for Early Gastric Cancer: SENORITA 2 Trial Protocol

Purpose

Although standard radical gastrectomy is recommended after noncurative resection of endoscopic submucosal dissection (ESD) for early gastric cancer in most cases, residual tumor and lymph node metastasis have not been identified after surgery. The aim of this study is to evaluate the feasibility of sentinel node navigation surgery after noncurative ESD.

Materials and Methods

This trial is an investigator-initiated, multicenter prospective phase II trial. Patients who underwent ESD for clinical stage T1N0M0 gastric cancer with noncurative resections were eligible. Qualified investigators who completed the prior phase III trial (SENORITA 1) are exclusively allowed to participate. In this study, 2 detection methods will be used: 1) intraoperative endoscopic submucosal injection of dual tracer, including radioisotope and indocyanine green (ICG) with sentinel basins detected using gamma-probe; 2) endoscopic injection of ICG, with sentinel basins detected using a fluorescence imaging system. Standard laparoscopic gastrectomy with lymphadenectomy will be performed. Sample size is calculated based on the inferior confidence interval of the detection rate of 95%, and the calculated accrual is 237 patients. The primary endpoint is detection rate, and the secondary endpoints are sensitivity and postoperative complications.

Conclusions

This study is expected to clarify the feasibility of laparoscopic sentinel basin dissection after noncurative ESD. If the feasibility is demonstrated, a multicenter phase III trial will be initiated to compare laparoscopic sentinel node navigation surgery versus laparoscopic standard gastrectomy in early gastric cancer after endoscopic resection.

Trial Registration

ClinicalTrials.gov Identifier: NCT03123042.

Techniques and Current Role of Sentinel Lymph Node (SLN) Concept in Gastric Cancer Surgery

Gastric cancer patients represent a rather divergent patient group and in certain carefully selected cases of early forms of gastric cancer the D2 gastrectomy could be considered a more radical procedure than the biological and oncological characteristics of the primary tumor on the gastric wall would require. As any unnecessary dissection increases morbidity without always respective survival benefits, an approach that could accurately predict and actually dictate the exact extent of lymph node dissection would be ideal. It is more than logical the assumption that the standard D2 lymphadenectomy could represent an overtreatment in distinct patients groups such as patients with early gastric cancer with favorable pathological characteristics and clinically negative nodes not suitable for endoscopic treatment because this early stage disease shows limited lymph node metastasis incidence and excellent overall survival. Considering that the D2 gastrectomy has a negative impact on the quality of life of gastric cancer patients due to the post-gastrectomy functional results, a concept of a more targeted lymph node dissection, when appropriate, is certainly appealing. It is yet to be proven whether sentinel lymph node navigation surgery can fulfill such expectations providing the appropriate balance between morbidity and oncological safety in selected gastric cancer patients.

Update on the indications and results of sentinel node mapping in upper GI cancer

The clinical utilization of sentinel node (SN) mapping for early esophageal cancer or gastric cancer has been unclear for a long time. However, previous investigations regarding SN mapping of these cancers have shown relatively good results with regard to the detection rate and diagnostic accuracy for determining the lymph node status. SN mapping helps obtain information about individual metastatic status and allows the modification of the operation in early-stage upper gastrointestinal (GI) disease. Radio-guided methods for identifying SNs in early esophageal cancer have been established via endoscopic injection of technetium-99m tin colloid. Previous studies have reported that the SN concept seems valid, and radio-guided SN mapping can be feasible in cT1N0 esophageal cancer. SN navigation surgery are believed to have potential as strategies for minimally invasive modified surgery for early esophageal cancer. A Japanese study group conducted a prospective multicenter trial of SN mapping for early gastric cancer using a dual tracer method with radioactive colloid and blue dyes; they demonstrated a high detection rate and accuracy for determining the metastatic status based on SN mapping. Subsequently, minimized gastrectomy, including partial gastrectomy and segmental gastrectomy with individualized selective and modified lymphadenectomy for early gastric cancer with a negative SN has been performed to evaluate the long-term survival and postoperative quality of life (QOL) in a multicenter prospective trial. This study verified the SN concept in early-stage upper GI disease with cN0 and found that function-preserving esophagectomy or gastrectomy may help maintain patients' post-surgical QOL.

Palliative surgery for advanced gastric cancer: Partial gastrectomy using the inverted laparoscopic and endoscopic cooperative surgery method

•

We performed partial gastrectomy with LECS as palliative treatment.

•

It was an invasive gastric cancer, but the patient had many comorbidities.

•

LECS was successfully used as minimally invasive palliative treatment.

Introduction

Laparoscopic and endoscopic cooperative surgery (LECS) is a minimally invasive hybrid procedure that facilitates the precise dissection of gastrointestinal malignancies. We report the use of LECS as palliative treatment for a patient with advanced gastric cancer at a high risk due to comorbidities.

Presentation of case

A 68-year-old woman with general malaise was admitted to the hospital and received multiple transfusions for anemia. Endoscopy examination detected an ulcerative lesion in the stomach. She was at high risk due to comorbidities including liver cirrhosis (Child-Pugh score B), aortic stenosis, and coronary artery stenosis requiring operative treatment.

Discussion

Imaging revealed no evidence of metastasis. We resected the tumor using LECS to control bleeding. Postoperatively, there were no short-term complications, and there was no recurrence during 6-month follow-up.

Conclusion

LECS as palliative treatment may be a viable option for high-risk patients with advanced gastric cancer.

Diagnostic evaluation of sentinel lymph node biopsy using indocyanine green and infrared or fluorescent imaging in gastric cancer: a systematic review and meta-analysis

BACKGROUND

Sentinel node navigation surgery (SNNS) for gastric cancer using infrared visualization of indocyanine green (ICG) is intriguing because it may limit operative morbidity. We are the first to systematically review and perform meta-analysis on the diagnostic utility of ICG and infrared electronic endoscopy (IREE) or near infrared fluorescent imaging (NIFI) for SNNS exclusively in gastric cancer.

METHODS

A search of electronic databases MEDLINE, EMBASE, SCOPUS, Web of Science, and the Cochrane Library using search terms "gastric/stomach" AND "tumor/carcinoma/cancer/neoplasm/adenocarcinoma/malignancy" AND "indocyanine green" was completed in May 2017. Articles were selected by two independent reviewers based on the following major inclusion criteria: (1) diagnostic accuracy study design; (2) indocyanine green was injected at tumor site; (3) IREE or NIFI was used for intraoperative visualization. 327 titles or abstracts were screened. The quality of included studies was assessed using the Quality Assessment of Diagnostic Accuracy Studies-2.

RESULTS

Ten full text studies were selected. 643 patients were identified with the majority of patients possessing T1 tumors (79.8%). Pooled identification rate, diagnostic odds ratio, sensitivity, and specificity were 0.99 (0.97-1.0), 380.0 (68.71-2101), 0.87 (0.80-0.93), and 1.00 (0.99-1.00), respectively. The summary receiver operator characteristic for ICG + IREE/NIFI demonstrated a test accuracy of 98.3%. Subgroup analysis found improved test performance for studies with low-risk QUADAS-2 scores, studies published after 2010 and submucosal ICG injection. IREE had improved diagnostic odds ratio, sensitivity, and identification rate compared to NIFI. Heterogeneity among studies ranged from low (I² < 25%) to high (I² > 75%).

CONCLUSIONS

We found encouraging results regarding the accuracy, diagnostic odds ratio, and specificity of the test. The sensitivity was not optimal but may be improved by a strict protocol to augment the technique. Given the number and heterogeneity of studies, our results must be viewed with caution.

Novel surgical approach based on the sentinel node concept in patients with early gastric cancer

Recent prospective multicenter trials have demonstrated the clinical safety and efficacy of sentinel node navigation surgery (SNNS) in patients with early gastric cancer. Further, development of an intraoperative imaging system and an indocyanine green fluorescence imaging approach has been attracting attention as a novel tool for detection of the sentinel node (SN). The greatest advantage of an in vivo imaging system is that it visualizes SN and afferent lymphatic vessels from the primary tumor site more clearly than the conventional dye approach. Besides visualization of the SN, it is also essential to accurately assess the presence or absence of lymph node metastasis in the intraoperative management of SNNS. However, the clinical significance of lymph node micrometastasis (LNM) in patients with gastric cancer remains controversial. Reverse transcription‐polymerase chain reaction (RT‐PCR) is one of the representative assays used to identify LNM. A rapid RT‐PCR assay that completes the detection of LNM within approximately 40 minutes has recently been produced and applied in the clinical management of SNNS. From the viewpoint of surgical methods, modified laparoscopic and endoscopic cooperative surgery with non‐exposed approaches has recently been highlighted as a promising technique to prevent tumor dissemination caused by surgical procedures, and is likely to be clinically applied to SNNS in the future. When carrying out SNNS as a minimally invasive surgery, it is important to consider the balance between post‐surgical quality of life and curability. Future prospective studies on SNNS will greatly contribute to furthering its establishment as a beneficial procedure for patients with early gastric cancer.

Feasibility and diagnostic performance of dual-tracer-guided sentinel lymph node biopsy in cT1-2N0M0 gastric cancer: a systematic review and meta-analysis of diagnostic studies

BACKGROUND

Dual-tracer-guided sentinel lymph node (SLN) biopsy may provide a promising diagnostic tool to assess accurately the status of lymph node metastasis in the surgical operation and assure the oncologic safety of the function or stomach preserving surgery. The diagnostic performance of this technology in recent studies varied. Thus, we conducted this meta-analysis.

METHODS

This systematic review and meta-analysis was registered at the PROSPERO. Eligible studies were searched in the PubMed, EMBASE, Web of Knowledge, and Cochrane Library databases. A random-effect model was used to pool the data. Summary receiver operator characteristic curves, analysis for publication bias, meta-regression, and subgroup analysis were also performed.

RESULTS

The pooled SLN identification rate and sensitivity were 0.97 and 0.89. ^99mTc-human serum albumin with indocyanine green (ICG), ^99mTc-antimony sulfur colloid with ICG, performing SLN biopsy ≥15 min after dye injection, an SLN ≥5, the basin dissection, laparoscopic surgery, in studies conducted in Japan and studies published after 2012, were associated with higher sensitivity. CT1 stage, performing SLN biopsy ≥15 min after dye injection, in studies conducted in Japan and studies published after 2012, were related with a higher identification rate.

CONCLUSIONS

Dual tracer is promising in SLN biopsy in gastric cancer, and the clinical application of SLN biopsy should be limited to the patients of cT1N0M0 gastric cancer. The combination of ^99mTc-human serum albumin and ICG as well as the combination of ^99mTc-antimony sulfur colloid and ICG may be the optimal tracer combination. However, it seems not justified to put this technique into routine clinical application recently. Some factors that might enhance diagnostic value are identified.

Laparoscopic sentinel node navigation surgery for early gastric cancer

Currently, the most accurate method for identifying lymph node metastasis is intraoperative diagnosis by sentinel node (SN) biopsy. Based on the SNNS study-a recent large-scale, nationwide, multicenter prospective study-the SN concept seems to be scientifically valid in patients with early gastric cancer. SN biopsy is a multistep technique consisted of six essential elements: indication, the selection of a tracer, a proper tracer injection method, the objective detection of SNs, a reliable biopsy technique, and the precise detection of nodal metastasis. For SN biopsy of gastric cancer, these elements have been validated as follows: the indication should be limited to clinical T1 less than 4 cm in diameter; combination mapping with radioactive colloid and blue dye is used as the standard; and endoscopic submucosal injection is the standard tracer injection. Detection of SNs and a reliable biopsy technique are enabled by adaptation of lymphatic basin dissection, a proper biopsy technique for gastric cancer. Lymphatic basin dissection is a selective lymphadenectomy procedure for dissecting basins en bloc, collecting lymph nodes and lymphatic vessels stained with dye. Lymphatic basin dissection is superior to the ordinary pick-up method, not only for minimizing the rate of missed SNs, but also in terms of oncological safety as it complements an intraoperative frozen section diagnosis by serving as a backup dissection. Moreover, indocyanine green (ICG) fluorescence mapping has been developed in recent years. ICG fluorescence mapping is superior because of its high sensitivity and signal stability. Moreover, it is feasible for both open and laparoscopic gastrectomy in treating early gastric cancer. SN biopsy has brought dramatic changes to laparoscopic surgery for early gastric cancer. With laparoscopic SN biopsy using ICG fluorescence navigation, laparoscopic surgery for early gastric cancer has changed from the uniform standard gastrectomy with D1+ into a tailor-made function-preserving surgical procedure, such as local resection with lymphatic basin dissection.

Function-preserving gastrectomy based on the sentinel node concept in early gastric cancer

Recent meta-analyses and a prospective multicenter trial of sentinel node (SN) mapping in early gastric cancer have demonstrated acceptable SN detection rates and accuracy of determination of lymph node status. SN mapping may play a key role in obtaining individual metastatic information. It also allows modification of surgical procedures, including function-preserving gastrectomy in patients with early gastric cancer. A dual-tracer method that uses radioactive colloids and blue dye is currently considered the most reliable method for the stable detection of SNs in patients with early gastric cancer. New technologies, such as indocyanine green infrared or fluorescence imaging, are also useful for accurate SN mapping in gastric cancer. Theoretically, laparoscopic function-preserving gastrectomy, including partial resection, proximal gastrectomy, segmental gastrectomy, and pylorus-preserving gastrectomy, is feasible in early gastric cancer when the SN(s) is/are nonmetastatic. Our study group conducted a multicenter prospective trial in Japan to evaluate function-preserving gastrectomy with SN mapping for long-term survival and patient quality of life. Non-exposed endoscopic wall-inversion surgery (NEWS) is a new technique for treating gastric cancer with partial resection involving full-thickness resection with endoscopy and laparoscopic surgery without transluminal access. The combination of NEWS and SN biopsy is expected to be a promising, minimally invasive, function-preserving surgery that is ideal for cases of cN0 early gastric cancer.

Immunohistochemical Study of Sentinel Lymph Node in Colon Cancer

Identification of sentinel lymph node (SLN) in colon cancer is very important in order to increase the accuracy of lymph node staging. The number of examined lymph nodes represents a significant predictor of survival. This study aims to show the importance of SLN histological and immunohistochemical examination in adjuvant oncological treatment. The study includes 23 patients with colon cancer (44% women and 56% men) who came in our clinic for surgical intervention. In all cases, the SLN was identified and prepared for histological examination. In 13 of the cases, micrometastases were found onhaematoxylin-eosin (HE) staining, there were 5 cases with positive immunohistochemistry using antibodies anti-p53, anti-VEGF-C, anti-CD34, and 5 cases with SLN negative both for HE and immunohistochemistry. Altogether we had a detection rate of 92%, an accuracy of 78,2%, a sensitivity of 90%, a false negative rate of 10% and a negative predictive value of 71,4%, good values according to the literature. Four (17,3%) patients had micrometastases exclusively in the sentinel lymph node, after performing additional histological examination, using multilevel section and immunohistochemistry. After assessing the SNL on our patients, we concluded that it is a reproducible practice for lymph node analysis.

Current status and challenges in sentinel node navigation surgery for early gastric cancer

Although a number of feasibility studies for sentinel node (SN) concepts in gastric cancer have been conducted since 2000, there remains a debate regarding detailed detection techniques and oncological safety. Two important multicenter phase II clinical trials were performed in Japan that used different methods and reached different conclusions; one confirmed acceptable results with a false-negative rate of 7%, and the other showed an unacceptably high false-negative rate of 46.4%. The Sentinel Node Oriented Tailored Approach (SENORITA) trial is a multicenter randomized controlled phase III trial being performed in Korea. Patient enrollment is now complete and the long-term results are currently awaited. Recently, an image-guided SN mapping technique using infrared ray/fluorescence was introduced. This method might be a promising technology because it allows the clear visualization of SNs. With regard to the primary tumor, the non-exposed endoscopic wall-inversion surgery technique and non-exposure endolaparoscopic full-thickness resection with simple suturing technique have been reported. These methods prevent abdominal infection and tumor seeding and can be good alternatives to conventional laparoscopic gastric wedge resection. For indications, SN navigation surgery can be extended to patients who underwent non-curative endoscopic resection. Although a few studies have been performed on these patients, sentinel concepts may be beneficial to patients as they omit the need for additional gastrectomy. SN navigation surgery can lead to actual organ-preserving surgery and plays a key role in improving the quality of life of patients with early gastric cancer in the future.

Sentinel node navigation in gastric cancer: new horizons for personalized minimally invasive surgical oncology?

Complete (R0) resection and regional lymph nodes (LNs) dissection represent undoubtedly the basic surgical tools for patients with gastric cancer. It is reported that the LN metastasis rate in patients with early gastric cancer (EGC) is approximately 15-20%. Therefore, the innovative clinical application of sentinel node navigation surgery (SNNS) for EGC might be able to prevent unnecessary LN dissection as well as to reduce significantly the volume of gastric resection. Recent evidence suggests that double tracer methods appear superior compared to single tracer techniques. However, the researchers' interest is now focused on the identification of new LN detection methods utilizing sophisticated technology such as infrared ray endoscopy, fluorescence imaging and near-infrared technology. Despite its notable limitations, hematoxylin-eosin is still considered the mainstay staining for assessing the metastatic status of LNs. In this review, we summarize the current evidences and we provide the latest scientific information assessing safety, efficacy and potential limitations of the innovative sentinel node (SN) navigation technique for gastric cancer. We try also to provide a "view" towards a future potential application of personalized minimally invasive surgery in gastric cancer field.

Secondary sentinel lymph node tracing technique: a new method for tracing lymph nodes in radical gastrectomy for advanced gastric cancer

OBJECTIVE

To explore the feasibility and clinical value of secondary sentinel lymph node (SSLN) tracing technique in radical gastrectomy for advanced gastric cancer (AGC).

METHODS

From January 2009 to June 2011, 247 patients who suffered from gastric angle cancer with metastasis in No. 3 group lymph nodes were divided randomly into groups A and B. Methylthioninium chloride was injected into the peripheral tissue of the metastatic No. 3 group lymph nodes of 138 patients in group A before tumor resections. SSLNs were traced and individual lymphadenectomies were carried out based on the biopsy results of the SSLNs. Standard D2 radical gastrectomies were carried out directly on 109 patients in group B. Postoperative follow-up and survival analysis were carried out for patients in both groups.

RESULTS

SSLNs were found in 114 (82.6%) patients in group A. Ninety of those patients (78.9%) demonstrated existing metastasis in SSLNs. According to Kaplan-Meier's method, the postoperative 3-year cumulative survival rates were 63.5% and 47.5%, and the median survival time were 40 and 36 months for the patients of groups A and B, respectively (P<0.05).

CONCLUSIONS

The SSLN tracing technique is feasible in radical gastrectomy for AGC. It gives surgeons important information about the terminal status of lymph node metastasis and provides some scientific basis for individual lymphadenectomy.

Pylorus-Preserving Surgery Based on the Sentinel Node Concept in Early Gastric Cancer

BACKGROUND

In patients with early stage gastric cancer in the middle third of the stomach, pylorus-preserving gastrectomy (PPG) can be an option as function-preserving surgery, although its oncologic safety is not definitively defined. This issues may be overcome using the sentinel node (SN) concept. The aim of this study was to investigate the effectiveness of the SN concept in early gastric cancer patients who are candidates for PPG.

METHODS

One hundred fifty-six patients with middle-third location of cT1N0 gastric cancer (single lesion, <4 cm) underwent distal gastrectomy with SN mapping. As a tracer, technetium-99 tin colloid solution and blue dye were endoscopically injected into the submucosal layer surrounding the primary tumor.

RESULTS

SN detection rate was 100 % (156 of 156), and the accuracy of the nodal evaluation of metastasis was 99 % (155 of 156). Suprapyloric lymph node (LN; LN No. 5) and infrapyloric LN (LN No. 6) were detected as SNs in 6 and 14 % of the patients, respectively. We also found two cases with metastasis to LN No. 5 or LN No. 6.

DISCUSSION

When performing PPG, the possibility of LN metastasis, especially to LN No. 5 and LN No. 6, cannot be underestimated. SN mapping can play an important role to predict the possibility of metastasis to LN No. 5 and LN No. 6.

Optimal settings and accuracy of indocyanine green fluorescence imaging for sentinel node biopsy in early gastric cancer

Indocyanine green (ICG) fluorescence imaging represents a promising method for sentinel node (SN) biopsy in laparoscopic gastric surgery due to its signal stability. In the present study, the suitability and optimal settings of ICG fluorescence imaging for SN biopsy in early gastric cancer were determined. Patients with single primary superficial-type adenocarcinoma of the stomach, lesions <5 cm in diameter, and no evident nodal metastasis and out of indication for endoscopic submucosal dissection were enrolled. The day prior to surgery, ICG solution was endoscopically injected into four quadrants of the submucosal layer of the tumor. The Photodynamic Eye was used to detect ICG fluorescence. Bright nodes were defined as clearly fluorescent nodes. A total of 72 patients were enrolled; 11 cases presented with metastasis, and of these, 10 could be diagnosed by bright node biopsy. The adequate concentration and injection volume of ICG was determined to be 50 µg/ml (×100) and 0.5 mlx4 points, respectively. There was 1 false-negative case, and this was attributed to the failure of the frozen section diagnosis. These results suggested that ICG fluorescence imaging for SN biopsy in laparoscopic surgery for early gastric cancer is feasible. However, a weakness of ICG fluorescence imaging is the subjectivity of bright node evaluation.

Endoscopic resection of early gastric cancer: current status and new approaches

Endoscopic resection (ER) of early gastric cancer (EGC) has been an optimal treatment for selected patients. As endoscopic submucosal dissection (ESD) has been widely used for treatment of EGC, concerns have been asked to achieve curative resection for EGC while guaranteeing precise prediction of lymph node metastasis (LNM). Moreover, a new microscopic imaging for precise endoscopic diagnosis of EGC is introduced. This review covers the current status and new approaches of ER of EGC.

Hybrid NOTES: Combined Laparo-endoscopic Full-thickness Resection Techniques

Advances in laparoscopic surgery and therapeutic endoscopy have allowed these minimally destructive procedures to challenge conventional surgery. Because of its theoretic advantages and technical feasibility, laparoendoscopic full-thickness resection is considered to be the most appropriate option for subepithelial tumor removal. Furthermore, combination of laparoscopic and endoscopic approaches for treatment of neoplasia can be important maneuvers for gastric cancer resection without contamination of the peritoneal cavity if the sentinel lymph node concept is established. We are certain that the use of laparoendoscopic full-thickness resection will provide valuable experience that will allow operators to safely develop endoscopic full-thickness resection skills.

Sentinel Lymph Node Navigation Surgery for Early Gastric Cancer: Is It a Safe Procedure in Countries with Non-Endemic Gastric Cancer Levels? A Preliminary Experience

Purpose

Early diagnosis of gastric cancer is still the exception in Western countries. In the East, as in Japan and Korea, this disease is an endemic disorder. More conservative surgical procedures are frequently performed in early gastric cancer cases in these countries where sentinel lymph node navigation surgery is becoming a safe option for some patients. This study aims to evaluate preliminary outcomes of patients with early gastric cancer who underwent sentinel node navigation surgeries in Brazil, a country with non-endemic gastric cancer levels.

Materials and Methods

From September 2008 to March 2014, 14 out of 205 gastric cancer patients underwent sentinel lymph node navigation surgeries, which were performed using intraoperative, endoscopic, and peritumoral injection of patent blue dye.

Results

Antrectomies with Billroth I gastroduodenostomies were performed in seven patients with distal tumors. The other seven patients underwent wedge resections. Sentinel basin resections were performed in four patients, and lymphadenectomies were extended to stations 7, 8, and 9 in the other 10. Two patients received false-negative results from sentinel node biopsies, and one of those patients had micrometastasis. There was one postoperative death from liver failure in a cirrhotic patient. Another cirrhotic patient died after two years without recurrence of gastric cancer, also from liver failure. All other patients were followed-up for 13 to 79 months with no evidence of recurrence.

Conclusions

Sentinel lymph node navigation surgery appears to be a safe procedure in a country with non-endemic levels of gastric cancer.

Minimally invasive function-preserving surgery based on sentinel node concept in early gastric cancer

Recent meta-analyses and a prospective multicenter trial of sentinel node (SN) mapping for early gastric cancer have shown acceptable SN detection rates and accuracy of determination of lymph node status. A dual-tracer method that employs radioactive colloids and blue dyes is currently considered the most reliable method for the stable detection of SNs in patients with early gastric cancer. However the new technologies such as indocyanine green (ICG) infrared or fluorescence imaging may revolutionize the SN mapping procedures in gastric cancer. For early stage gastric cancer, the establishment of individualized, minimally invasive treatments based on SN concept can retain the patients' quality of life (QOL). The combination of non-exposed endoscopic wall-inversion surgery (NEWS) with SN biopsy is expected to become a promising, ideal minimally invasive, function-preserving surgery to cure cases of cN0 early gastric cancer.

Sentinel lymph node navigation surgery for gastric cancer: Does it really benefit the patient?

Sentinel lymph node (SLN) navigation surgery is accepted as a standard treatment procedure for malignant melanoma and breast cancer. However, the benefit of reduced lymphadenectomy based on SLN examination remains unclear in cases of gastric cancer. Here, we review previous studies to determine whether SLN navigation surgery is beneficial for gastric cancer patients. Recently, a large-scale prospective study from the Japanese Society of Sentinel Node Navigation Surgery reported that the endoscopic dual tracer method, using a dye and radioisotope for SLN biopsy, was safe and effective when applied to cases of superficial and relatively small gastric cancers. SLN mapping with SLN basin dissection was preferred for early gastric cancer since it is minimally invasive. However, previous studies reported that limited gastrectomy and lymphadenectomy may not improve the patient’s postoperative quality of life (QOL). As a result, the benefit of SLN navigation surgery for gastric cancer patients, in terms of their QOL, is limited. Thus, endoscopic and laparoscopic limited gastrectomy combined with SLN navigation surgery has the potential to become the standard minimally invasive surgery in early gastric cancer.

Sentinel node navigation surgery with indocyanine green fluorescence-guided method for metachronous early gastric carcinoma arising from reconstructed gastric tube after esophagectomy

A 67-year-old man who had undergone a thoracoscopic esophagectomy and posterior mediastinal gastric tube reconstruction for thoracic esophageal cancer 9 years previously was endoscopically diagnosed as having gastric carcinoma arising from the reconstructed gastric tube. No evidence of metastasis was seen in imaging examinations, and the depth of tumor invasion was suspected to be the submucosal layer. Based on these results, we decided that surgery, rather than endoscopic resection, was indicated. The tumor was located in the upper abdomen. Therefore, we performed a partial resection of the gastric tube. Sentinel nodes (SN) were identified using the Hyper Eye Medical System II. Metastasis was not observed in any of the selected SN. While the treatment strategy for gastric tube cancer after an esophagectomy remains controversial, minimally invasive surgery with sentinel node navigation surgery appears to be clinically useful. However, the method of SN dissection should be investigated with due consideration given to arterial preservation.

Clinical significance of lymphadenectomy in patients with gastric cancer

Approximately thirty percent of patients with gastric cancer undergo an avoidable lymph node dissection with a higher rate of postoperative complication. Comparing the D1 and D2 dissections, it was found that there is a significant difference in morbidity, favoured D1 dissection without any difference in overall survival. Subgroup analysis of patients with T3 tumor shows a survival difference favoring D2 lymphadenectomy, and there is a better gastric cancer-related death and non-statistically significant improvement of survival for node-positive disease in patients with D2 dissection. However, the extended lymphadenectomy could improve stage-specific survival owing to the stage migration phenomenon. The deployment of centralization and application of national guidelines could improve the surgical outcomes. The Japanese and European guidelines enclose the D2 lymphadenectomy as the gold standard in R0 resection. In the individualized, stage-adapted gastric cancer surgery the Maruyama computer program (MCP) can estimate lymph node involvement preoperatively with high accuracy and in addition the Maruyama Index less than 5 has a better impact on survival, than D-level guided surgery. For these reasons, the preoperative application of MCP is recommended routinely, with an aim to perform “low Maruyama Index surgery”. The sentinel lymph node biopsy (SNB) may decrease the number of redundant lymphadenectomy intraoperatively with a high detection rate (93.7%) and an accuracy of 92%. More accurate stage-adapted surgery could be performed using the MCP and SNB in parallel fashion in gastric cancer.

Laparoscopic gastric cancer surgery: Current evidence and future perspectives

Laparoscopic gastrectomy has been widely accepted as a standard alternative for the treatment of early-stage gastric adenocarcinoma because of its favorable short-term outcomes. Although controversies exist, such as establishing clear indications, proper preoperative staging, and oncologic safety, experienced surgeons and institutions have applied this approach, along with various types of function-preserving surgery, for the treatment of advanced gastric cancer. With technical advancement and the advent of state-of-the-art instruments, indications for laparoscopic gastrectomy are expected to expand as far as locally advanced gastric cancer. Laparoscopic gastrectomy appears to be promising; however, scientific evidence necessary to generalize this approach to a standard treatment for all relevant patients and care providers remains to be gathered. Several multicenter, prospective randomized trials in high-incidence countries are ongoing, and results from these trials will highlight the short- and long-term outcomes of the approach. In this review, we describe up-to-date findings and critical issues regarding laparoscopic gastrectomy for gastric cancer.

Sentinel lymph node biopsy in gastric cancer

Clinical application of sentinel lymph node (SLN) mapping in patients with early-stage gastric cancer has been a controversial issue for years. However, a recent meta-analysis and a prospective multicenter trial of SLN mapping for early-stage gastric cancer have shown acceptable SLN detection rates and accuracy of determination of lymph node status. A dual-tracer method that uses radioactive colloids and blue dyes is currently considered the most reliable method for the stable detection of SLNs in patients with early-stage gastric cancer. However, the new technologies such as indocyanine green infrared or fluorescence imaging might revolutionize the SLN mapping procedures in gastric cancer. For early-stage gastric cancer, the establishment of individualized, minimally invasive treatments based on SLN concept may retain the patients' quality of life.