Possibility of limited gastrectomy for early gastric cancer located in the upper third of the stomach, based on the distribution of sentinel node basins. Surg Today. 2019;49:529-535. [PMID: 30684050 DOI: 10.1007/s00595-019-1768-6]

Non-exposed endoscopic wall-inversion surgery with one-step nucleic acid amplification for early gastrointestinal tumors: Personal experience and literature review

BACKGROUND

Laparoscopic and endoscopic cooperative surgery is a safe, organ-sparing surgery that achieves full-thickness resection with adequate margins. Recent studies have demonstrated the safety and efficacy of these procedures. However, these techniques are limited by the exposure of the tumor and mucosa to the peritoneal cavity, which could lead to viable cancer cell seeding and the spillage of gastric juice or enteric liquids into the peritoneal cavity. Non-exposed endoscopic wall-inversion surgery (NEWS) is highly accurate in determining the resection margins to prevent intraperitoneal contamination because the tumor is inverted into the visceral lumen instead of the peritoneal cavity. Accurate intraoperative assessment of the nodal status could allow stratification of the extent of resection. One-step nucleic acid amplification (OSNA) can provide a rapid method of evaluating nodal tissue, whilst near-infrared laparoscopy together with indocyanine green can identify relevant nodal tissue intraoperatively.

AIM

To determine the safety and feasibility of NEWS in early gastric and colon cancers and of adding rapid intraoperative lymph node (LN) assessment with OSNA.

METHODS

The patient-based experiential portion of our investigations was conducted at the General and Oncological Surgery Unit of the St. Giuseppe Moscati Hospital (Avellino, Italy). Patients with early-stage gastric or colon cancer (diagnosed via endoscopy, endoscopic ultrasound, and computed tomography) were included. All lesions were treated by NEWS procedure with intraoperative OSNA assay between January 2022 and October 2022. LNs were examined intraoperatively with OSNA and postoperatively with conventional histology. We analyzed patient demographics, lesion features, histopathological diagnoses, R0 resection (negative margins) status, adverse events, and follow-up results. Data were collected prospectively and analyzed retrospectively.

RESULTS

A total of 10 patients (5 males and 5 females) with an average age of 70.4 ± 4.5 years (range: 62-78 years) were enrolled in this study. Five patients were diagnosed with gastric cancer. The remaining 5 patients were diagnosed with early-stage colon cancer. The mean tumor diameter was 23.8 ± 11.6 mm (range: 15-36 mm). The NEWS procedure was successful in all cases. The mean procedure time was 111.5 ± 10.7 min (range: 80-145 min). The OSNA assay revealed no LN metastases in any patients. Histologically complete resection (R0) was achieved in 9 patients (90.0%). There was no recurrence during the follow-up period.

CONCLUSION

NEWS combined with sentinel LN biopsy and OSNA assay is an effective and safe technique for the removal of selected early gastric and colon cancers in which it is not possible to adopt conventional endoscopic resection techniques. This procedure allows clinicians to acquire additional information on the LN status intraoperatively.

Use of fluorescence imaging and indocyanine green for sentinel node mapping during gastric cancer surgery: Results of an intercontinental Delphi survey

BACKGROUND

Understanding the extent of tumor spread to local lymph nodes is critical to managing early-stage gastric cancer. Recently, fluorescence imaging with indocyanine green has been used to identify and characterize sentinel lymph nodes during gastric cancer surgery, but no published guidelines exist. We sought to identify areas of consensus among international experts in the use of fluorescence imaging with indocyanine green for mapping sentinel lymph nodes during gastric-cancer surgery.

METHODS

In this 2-round, online Delphi survey, 27 international experts voted on 79 statements pertaining to patient preparation and contraindications to fluorescence imaging with indocyanine green during gastric cancer surgery; indications; technical aspects; advantages/disadvantages and limitations; and training and research. Methodological steps were adopted during survey design to minimize bias.

RESULTS

Consensus was reached on 61 of 79 statements, including giving single injections of indocyanine green into each of the 4 quadrants peritumorally, administering indocyanine green on the same day as surgery, injecting a total of 1 to 5 mL of 5 mg/mL indocyanine green, injecting endoscopically into submucosa, and repeating indocyanine green injections a second time if sentinel lymph node visualization remains inadequate. Consensus also was reached that fluorescence imaging with indocyanine green is an acceptable single-agent modality for sentinel lymph node identification and that the sentinel lymph node basin method is preferred. However, sentinel lymph node dissection should be limited to T1 gastric cancer and tumors ≤4 cm in diameter, and further research is necessary to optimize the technique and render fluorescence-guided sentinel lymph nodes dissection acceptable for routine clinical use.

CONCLUSION

Although considerable consensus was achieved, further research is necessary before this technology should be used in routine practice.

Characteristics of lymph node stations/basins metastasis and construction and validation of a preoperative combination prediction model that accurately excludes lymph node metastasis in early gastric cancer

Objective

To explore the candidate indications for function-preserving curative gastrectomy and sentinel lymph node navigation surgery in early gastric cancer (EGC).

Methods

The clinicopathological data of 561 patients with EGC who underwent radical gastrectomy for gastric cancer at Peking University Cancer Hospital from November 2010 to November 2020 with postoperative pathological stage pT1 and complete examination data, were collected. Pearson's Chi-square test was used and binary logistic regression was employed for univariate and multivariate analyses. Combined analysis of multiple risk and protective factors for lymph node metastasis (LNM) of EGC was performed. A negative predictive value (NPV) combination model was built and validated.

Results

LNM occurred in 85 of 561 patients with EGC, and the LNM rate was 15.15%. NPV for LNM reached 100% based on three characteristics, including ulcer-free, moderately well differentiation and patient <65 years old or tumor located at the proximal 1/3 of the stomach. Regarding lymphatic basin metastasis, multivariate analysis showed that the metastatic proportion of the left gastric artery lymphatic basin was significantly higher in male patients compared with female patients (65.96% vs. 38.89%, P<0.05). The proportion of right gastroepiploic artery lymphatic basin metastasis in patients with a maximum tumor diameter >2 cm was significantly greater than that noted in patients with a maximum tumor diameter ≤2 cm (60.78% vs. 28.13%, P<0.05).

Conclusions

Characteristics of lymph node stations/basins metastasis will facilitate precise lymph node resection. The NPV for LNM reaches 100% based on the following two conditions: young and middle-aged EGC patients, well-differentiated tumors, and without ulcers; or well-differentiated tumors, without ulcers, and tumors located in the proximal stomach. These findings can be used as the recommended indications for function-preserving curative gastrectomy and sentinel lymph node navigation surgery.

Risks and benefits of additional surgery for early gastric cancer in the upper third of the stomach meeting non-curative resection criteria after endoscopic submucosal dissection

Background

Additional surgery is recommended after non-curative endoscopic submucosal dissection for early gastric cancer. However, it is not easy to recommend for tumors located in the upper third of the stomach, because it would be a total or proximal gastrectomy. This study aimed to evaluate the actual risks and benefits of additional gastrectomy for upper third tumors.

Methods

We reviewed the clinicopathological data of patients who underwent total or proximal gastrectomy for early gastric cancer in the upper third of the stomach between March 2002 and January 2021. The incidence of lymph node metastasis and postoperative complications were calculated, and risk factors for lymph node metastasis were identified using logistic regression analysis. Survival rates were analyzed using the Kaplan–Meier method and log-rank test.

Results

A total of 523 patients underwent total or proximal gastrectomy for early gastric cancer; 379 of them had tumors meeting the non-curative resection criteria for endoscopic submucosal dissection. The overall lymph node metastasis rate was 9.5%, and lymphovascular invasion was the only significant risk factor for lymph node metastasis (p < 0.001). The most common sites of lymph node metastasis were stations 1, 3, and 7, with their rates being 3.2%, 3.7%, and 3.2%, respectively. Overall and severe (Clavien–Dindo grade III or higher) postoperative complication rates were 21.1% and 14.0%, respectively, while postoperative mortality was 0.5% (2/379). The 5-year overall survival rates for patients with and without lymph node metastasis were 96.1% and 81.1%, respectively (p = 0.076).

Conclusions

Before planning an additional gastrectomy after non-curative endoscopic resection for the upper third tumor, we should consider both the benefit of the 9.5% curability for lymph node metastasis and the risks of the 21% postoperative complications and 0.5% mortality.

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.

A Systematic Review and Meta-Analysis of Sentinel Lymph Node Biopsy in Gastric Cancer, an Optimization of Imaging Protocol for Tracer Mapping

BACKGROUND

Sentinel lymph node biopsy (SLNB) plays an essential role in the evaluation of lymph node (LN) metastasis status and the extent of LN dissection in gastric cancer. The aim of our study was to perform a systematic review and meta-analysis for corresponding identification rate and sensitivity of different SLNB techniques.

METHODS

Systematic search using PubMed, Embase, and Cochrane library databases was conducted for studies on SLNB in patients with gastric cancer. Studies were stratified according to the sentinel lymph node (SLN) biopsy technique: blue dye (BD), radiocolloid tracer (RI), indocyanine green (ICG), a combination of radiocolloid with blue dye (RI + BD), and a combination of radiocolloid with ICG (RI + ICG). A random-effect model was used to pool the identification rate, sensitivity, and accuracy.

RESULTS

A total of 54 eligible studies (3767 patients) was included. The pooled identification rates of SLNB using BD, RI, ICG, RI + BD, RI + ICG were 95% (95%CI: 92-97%), 95% (95%CI: 93-97%), 99% (95%CI: 97-99%), 97% (95%CI: 96-98%), and 95% (95%CI: 87-99%), respectively. The pooled sensitivities were 82% (95%CI: 77-86%), 87% (95%CI: 81-92%), 90% (95%CI: 82-95%), 89% (95%CI: 84-93%), and 88% (95%CI: 79-94%), respectively. The pooled accuracies were 94% (95%CI: 91-96%), 95% (95%CI: 92-97%), 98% (95%CI: 95-99%), 97% (95%CI: 95-99%), and 98% (95%CI: 95-99%), respectively.

CONCLUSIONS

The current meta-analysis provides reliable evidence that favors the use of ICG and dual tracer method (RI + BD/ICG) for the identification of the SLN. Considering the high costs and potential biohazard of using radioactive substances in dual tracer method, performing SLNB with ICG is the technique of choice for experienced surgeons.

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

As an optimal surgical procedure to accurately evaluate lymph node (LN) metastasis during surgery with minimal surgical resection, we have been developing sentinel node (SN) biopsy for early gastric cancer since the 1990s. Twelve institutions from the Japanese Society of Sentinel Node Navigation Surgery (SNNS), including Keio University Hospital, conducted a multicenter prospective trial to validate the SN concept using the dual-tracer method with blue dye and a radioisotope. According to the results, 397 patients were included in the final analysis, and the overall accuracy in detecting LN metastasis using SN biopsy was 99% (383 of 387). Based on the validation study, we are targeting cT1N0 with a primary tumor of ≤4 cm in diameter as an indication for SN biopsy for gastric cancer. We are currently running a multicenter nonrandomized phase III trial to assess the safety and efficacy of SN navigation surgery. The Korean group has reported the result of a multicenter randomized phase III trial. Since meticulous gastric cancer in the remnant stomach was rescued by subsequent gastrectomy, the disease-specific survival was comparable between the two techniques, implying that SN navigation surgery can be an alternative to standard gastrectomy. With the development of SN biopsy procedure and treatment modalities, the application of SN biopsy will be expanded to achieve an individualized minimally invasive surgery.

RPL38 Regulates the Proliferation and Apoptosis of Gastric Cancer via miR-374b-5p/VEGF Signal Pathway

Aim

To explore the role of RPL38 on proliferation and apoptosis of gastric cancer cells by regulating miR-374b-5p/VEGF signal pathway.

Methods

qRT-PCR was used to measure the expression of RPL38. CCK8 assay, Matrigel invasion assay, and flow cytometry were used to detect the role of RPL38in MKN-45 cells. Western blot was used to measure the protein expression of VEGF, p-ERK, ERK, p-AKT, AKT in cells. Dual-luciferase assay was performed to verify the relationship between miR-374b-5p and RPL38, miR-374b-5p and VEGF.

Results

In our research, we found that RPL38 was upregulation in gastric cancer, loss function of RPL38 could inhibit MKN-45 cell proliferation and invasion, accompany with increasing apoptosis. Then, we verified that RPL38 could interact with miR-374b-5p by performed luciferase assay, there was a negative correlation between RPL38 and miR-374b-5p. Furthermore, we observed that VEGF is a potential target of miR-374b-5p, miR-374b-5p negatively regulated the expression of VEGF, and effected ERK/AKT signal pathways. Next, we found that miR-374b-5p inhibitor or overexpression of VEGF could prevent the anti-tumor function of si-RPL38.

Conclusion

Knockdown of RPL38 inhibits the proliferation and apoptosis of gastric cancer via miR-374b-5p/VEGF signal pathway.

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.

Survival outcomes after sentinel node navigation surgery for early gastric cancer

AIM

This study evaluated the prognosis after sentinel node navigation surgery (SNNS) for early gastric cancer.

METHODS

For 100 patients who underwent SNNS (between August 13, 2003 and December 17, 2018) at our hospital, the survival outcomes were investigated.

RESULTS

(a) SN were detected with a diagnostic accuracy of 0.98. (b) Of seven patients who had positive SN metastasis, three underwent standard gastrectomy with D2 lymph node dissection. Among them, one patient died of recurrence (bone) and the other two patients were alive 4.5 and 14.7 years after surgery. The remaining four patients with positive SN who underwent diminished gastrectomy with lymphatic basin dissection at their request are alive 2.8, 6.0, 6.9 and 10.8 years after surgery without recurrence. (c) No patients who underwent diminished gastrectomy died of gastric cancer after surgery. (d) In the period following diminished gastrectomy, one patient underwent total gastrectomy and five patients underwent endoscopic submucosal dissection, and they survived for longer than 5 years. (e) As a result of SNNS, the gastric cancer-specific cumulative 5-year survival rate was 98.5%.

CONCLUSIONS

Diminished gastrectomy during SNNS resulted in a satisfactory prognosis. However, regular follow-up after surgery is needed to detect secondary cancer of the remaining stomach.