Precision surgical approach with lymph-node dissection in early gastric cancer

Lymph node metastasis mapping and prognostic analysis of early gastric cancer

BACKGROUND

Currently, numerous studies focus on the analysis of risk factors for lymph node metastasis in early gastric cancer, but few studies analyze the drainage patterns of metastatic lymph nodes.

METHODS

Data were retrospectively analyzed from a database of gastric cancer resections from 2014 to 2018. The cohort included 786 pT1 patients with complete data. Outcomes evaluated were lymph node metastasis frequencies, survival analyses, and risk factors affecting prognosis.

RESULTS

The overall lymph node metastasis rate was 23.7%. The 5-year overall survival (OS) rate (54.8% vs 95.7%; P <.001) and disease-free survival (DFS) rate (48.4% vs 95.7%; P <.001) of patients with node-positive disease were significantly worse than those of patients with node-negative disease. Multivariable Cox regression identified tumor size of >2 cm (P =.007; P <.001), poor differentiation (P =.007; P <.001), T1b stage (all P <.001), lymph node metastasis (all P <.001), and vascular invasion (all P =.002; P =.016) as independent negative prognostic factors affecting 5-year OS and DFS in patients with early gastric cancer. Postoperative chemotherapy (P <.001; P =.019) was an independent positive prognostic factor.

CONCLUSION

This real-world observational study demonstrates that lymph node metastasis in early gastric cancer is widely and disorderly not depending on the location. Therefore, systematic lymph node dissection is necessary to cure early gastric cancer. Meanwhile, its prognosis is closely related to lymph node metastasis.

Biomimetic Cascade Nanozyme Catalytic System for the Treatment of Lymph Node Metastasis in Gastric Cancer

Lymphatic metastasis of gastric cancer is a challenging issue in clinical practice. Recently, copper single-atom nanozymes (SAZ) have gained tremendous attention due to its superior peroxidase (POD) activity that has good nonocatalytic tumor therapy (NCT) capabilities, and photothermal properties. Therefore, using a high-expressing P-selectin platelet membrane (PM) to encapsulate SAZ and cisplatin is proposed, forming PSC nanoparticles. Due to their exquisite nanoscale size and the unique structure of lymphatic vessels, PSC can highly target cancer cells in invasive primary tumors and metastatic lymph nodes that both highly express CD44. It is noteworthy that cisplatin can simultaneously perform chemotherapy and generate H₂O₂ under the action of NADPH oxidases (NOXs) that further enhance the catalytic activity of SAZ and increase intracellular reactive oxygen species (ROS) production. Both in vitro and vivo experiments have demonstrated the superior targeting and elimination capability of the PCS system in primary and metastatic tumor cells. In addition, transcriptomic analysis reveals that PSC + NIR induced apoptosis in MFC cells. This marks the first proposal of combining single-atom nanozymes and chemotherapy drugs for dual-targeting in gastric cancer and lymphatic metastasis, providing new insights into a challenging clinical issue in the treatment of gastric cancer lymphatic metastasis.

Sealed endoscopic full-thickness resection with sentinel node navigation for early gastric cancer without endoscopic submucosal dissection indication

Background and study aims

Laparoscopic and endoscopic cooperative surgery (LECS) is a beneficial procedure that enables minimal resection of the gastric wall because the tumor can be located endoscopically. However, it is not indicated for epithelial tumors because of risk of peritoneal dissemination. Therefore, we devised a new LECS technique, known as sealed endoscopic full-thickness resection (sealed EFTR), in which the serosa was sealed with a silicone sheet to prevent escape of gastric contents and tumor cells. The aims of this study were to evaluate the safety and feasibility of a newly developed procedure and to observe its long-term outcomes, including absence of local recurrence and peritoneal dissemination.

Patients and methods

Approval was obtained from the Ethics Review Committee of the Japan Consortium for Advanced Surgical Endoscopy Study Group. Between December 2011 and July 2021, at Kanazawa Medical University Hospital, 16 patients with cT1 gastric cancer were enrolled in this study. Sealed EFTR was performed in patients diagnosed with negative lymph node metastasis via intraoperative sentinel node biopsy.

Results

Among the 16 enrolled patients, 12 (75%) had negative sentinel node metastases, 11 of whom underwent sealed EFTR. Except for two patients who died from other causes, no instances of metastasis or recurrence were observed during the mean follow-up period of 6.5 years (range, 2-11).

Conclusions

This study suggests that appropriate case selection for sentinel lymph node biopsy could allow for oncologically safe and individualized minimally invasive surgery for early gastric cancer that is ineligible for endoscopic submucosal dissection.

Construction and validation of a nomogram based on the log odds of positive lymph nodes to predict the prognosis of T1 gastric cancer

In patients with gastric cancer (GC), metastatic progression through the lymphatic, haematogenous, peritoneal, and ovarian routes is the ultimate cause of death. We developed a nomogram to estimate cancer-specific survival (CSS) in patients with T1 gastric cancer based on log odds of positive lymph nodes (LODDS). A total of 2,221 patients from the Surveillance, Epidemiology, and End Results (SEER) database were split into training and internal validation cohorts, while an external validation cohort included 165 patients from our hospital. Multivariate Cox regression analysis revealed that age, sex, tumour size, LODDS score, and M stage were independent prognostic factors for CSS. The LODDS outperformed the N stage and positive lymph node (PLN) count in terms of predictive ability and is recognised as an independent prognostic factor for nomogram construction. In the training and internal and external validation sets, the 1-year AUCs of the columniogram were 0.732, 0.672, and 0.719, respectively. The 3-year AUCs were 0.705, 0.692, and 0.638, respectively. The 5-year AUCs were 0.726, 0.698, and 0.713, respectively, indicating good predictive power. The calibration curve revealed that the predicted survival rate was consistent with the actual survival rate in the three groups. The ROC and DCA demonstrated that the nomogram has more potential in predicting prognosis than the existing AJCC staging system. We constructed and validated a novel nomogram leveraging LODDS, which effectively estimates the CSS at 1, 3, and 5 years for individuals with gastric cancer.

Predictive Value of Preoperative Peripheral Blood Inflammatory Markers for Surgical Site Infection in Laparoscopic Radical Gastrectomy for Gastric Cancer

Background: To investigate the predictive value of preoperative peripheral blood inflammatory markers for surgical site infection (SSI) in laparoscopic radical gastrectomy for gastric cancer. Methods: A retrospective analysis was conducted on patients undergoing laparoscopic radical gastrectomy for gastric cancer, categorized into SSI and non-SSI groups based on postoperative SSI occurrences. Patient demographics, surgical details, laboratory results, and SSI incidence data were extracted. Differences in indicators, including neutrophil-lymphocyte ratio (NLR), systemic immune-inflammation index (SII), and platelet-lymphocyte ratio (PLR), were assessed between the two groups. Multivariate logistic regression was utilized to determine the independent association of each indicator with SSI. Receiver operating characteristics (ROC) curve analysis was utilized to evaluate the predictive value of parameters. Results: Of 169 patients, 36 (21.30%) experienced SSI postoperatively. The SSI group exhibited higher preoperative NLR and SII (p < 0.05). After adjusting for variables, preoperative NLR (OR = 1.691, 95% CI: 1.211-2.417, p = 0.003) and SII (OR = 1.001, 95% CI: 1.000-1.002, p = 0.006) were identified as independent risk factors for SSI. Both NLR (AUC = 0.758, 95% CI: 0.666-0.850) and SII (AUC = 0.753, 95% CI: 0.660-0.850) demonstrated favorable diagnostic performance for predicting postoperative SSI. Conclusion: Preoperative NLR and SII significantly associate with postoperative SSI in laparoscopic radical gastrectomy for gastric cancer, making them valuable indicators for early prediction of SSI.

Identification of a novel gene signature related to prognosis and metastasis in gastric cancer

BACKGROUND

Gastric Cancer (GC) presents poor outcome, which is consequence of the high incidence of recurrence and metastasis at early stages. GC patients presenting recurrent or metastatic disease display a median life expectancy of only 8 months. The mechanisms underlying GC progression remain poorly understood.

METHODS

We took advantage of public available GC datasets from TCGA using GEPIA, and identified the matched genes among the 100 genes most significantly associated with overall survival (OS) and disease free survival (DFS). Results were confirmed in ACRG cohort and in over 2000 GC cases obtained from several cohorts integrated using our own analysis pipeline. The Kaplan-Meier method and multivariate Cox regression analyses were used for prognostic significance and linear modelling and correlation analyses for association with clinic-pathological parameters and biological hallmarks. In vitro and in vivo functional studies were performed in GC cells with candidate genes and the related molecular pathways were studied by RNA sequencing.

RESULTS

High expression of ANKRD6, ITIH3, SORCS3, NPY1R and CCDC178 individually and as a signature was associated with poor prognosis and recurrent disease in GC. Moreover, the expression of ANKRD6 and ITIH3 was significantly higher in metastasis and their levels associated to Epithelial to Mesenchymal Transition (EMT) and stemness markers. In line with this, RNAseq analysis revealed genes involved in EMT differentially expressed in ANKRD6 silencing cells. Finally, ANKRD6 silencing in GC metastatic cells showed impairment in GC tumorigenic and metastatic traits in vitro and in vivo.

CONCLUSIONS

Our study identified a novel signature involved in GC malignancy and prognosis, and revealed a novel pro-metastatic role of ANKRD6 in GC.

Long‑term survival prognosis of function‑preserving curative gastrectomy for early gastric cancer

Segmental gastrectomy, mini-distal gastrectomy and local resection of the stomach are function-preserving curative gastrectomies (FPGs), which are used to treat gastric cancer in specialized centers. These surgical options are less invasive and can alleviate postgastrectomy symptoms more than standard gastrectomy; however, their association with prognosis remains to be fully elucidated. The present study aimed to compare the survival prognosis of patients diagnosed as node-negative by sentinel node biopsy (SNB) treated via FPG with reduced lymph node dissection with that of patients who underwent guideline gastrectomy (GL). This retrospective study was conducted between April 1999 and March 2016. The inclusion criteria were a diagnosis of gastric cancer type 0, of ≤5 cm, located in L or M areas, and pT1N0. Patients who underwent distal gastrectomy and pylorus-preserving gastrectomy were included as controls in the GL group. Among the 146 and 300 patients in the FPG and GL groups, respectively, only 1 patient in the GL group experienced recurrence. The overall survival (OS) of the FPG group was 96.6% at 5 years and 92.5% at 10 years, which was significantly higher than that of the GL group (P<0.05). In addition, the cumulative incidence of non-cancer-related deaths, especially pulmonary diseases, was lower in the FPG group than that in the GL group (P<0.05). Notably, the OS and non-cancer death rate in the FPG group remained significantly better after propensity score-matching analysis. In conclusion, for early gastric cancer located in M or L areas, patients treated via FPG guided by SNB have a better prognosis and fewer deaths caused by respiratory disease than those treated via GL. The present clinical trial was registered under the following trial registration numbers: UMIN000010154 (2013/3/4), UMIN000023828 (2016/8/29), jRCTs041180006 (2018/10/9).

The influence of partial gastrectomy for gastric cancer on the spontaneous disappearance of Helicobacter pylori: A single-center prospective study

BACKGROUND/AIMS

Helicobacter pylori (HP) eradication is recommended after endoscopic treatment of early gastric cancer (EGC). Cases of spontaneous HP resolution after partial gastrectomy due to environmental changes have been reported; however, there is no evidence for the efficacy of HP eradication in suppressing carcinogenesis and also no reports on the natural history of HP after partial gastrectomy in gastric cancer (GC). To report the natural history of HP in patients with GC and HP infection after partial gastrectomy.

METHODS AND RESULTS

We prospectively studied the rate of spontaneous disappearance of HP after partial gastrectomy in patients with GC. From April 2016 to May 2020, 80 patients underwent partial gastrectomy, including 9 cases of proximal gastrectomy (PG), and 71 cases of distal gastrectomy (DG). The presence of HP was confirmed in the stool antigen test 1 year after operation, HP infection persisted in 46 patients (57.5%) and disappeared in 34 patients (42.5%). In univariate analysis, only proton pump inhibitor (PPI) use was a significant contributing factor for the spontaneous resolution of HP infection, especially in the DG group. However, there was no difference in the rates of HP disappearance between Billroth-I and Roux-en-Y reconstructions in the DG group.

CONCLUSION

The HP spontaneously disappeared in 42.5% of the GC patients within 1 year after partial gastrectomy. Further investigation in a larger cohort is needed to elucidate the underlying mechanisms.

CD45- erythroid progenitor cells promote lymph node metastasis in gastric cancer by inducing a hybrid epithelial/mesenchymal state in lymphatic endothelial cells

BACKGROUND AND AIMS

Specific mechanisms of lymph node (LN) metastasis in early-stage gastric cancer (GC) have not been elucidated. The role of anemia, a vital clinical feature of GC, in LN metastasis is also unclear. Since the number of erythroid progenitor cells (EPCs) is increased in chronic anemia, we investigated its association with LN metastasis in GC.

METHODS

Flow cytometry and immunofluorescence analyses were performed to sort and study EPCs from the circulation and tumors of patients with stage I-III GC. The effect of these EPCs on the activation of T and B cells and on the functions of lymphatic endothelial cells (LECs) was determined, and their ability to promote LN metastasis was evaluated using a footpad-popliteal LN metastasis model based on two human adenocarcinoma GC cell lines in nude mice. The prognostic value of EPCs was also analyzed.

RESULTS

The proportion of CD45- EPCs was higher in the mononuclear cells in the circulation, tumors, and LNs of GC patients with LN metastasis (N+) than in those of GC patients without LN metastasis (N0). In N+ patients, CD45- EPCs were more abundant in metastatic LNs than in non-metastatic LNs. Lymphatic vessel endothelial hyaluronan receptor 1 immunoreactivity in tumors revealed that CD45- EPCs were positively associated with nodal stages and lymph vessel density. Furthermore, CD45- EPCs increased LEC proliferation and migration through their S100A8/A9 heterodimer-induced hybrid epithelial/mesenchymal (E/M) state; however, they did not influence the invasion and tubulogenesis of LECs or T and B cell proliferation. CD45- EPCs promoted LN metastasis in vivo; the S100A8/A9 heterodimer mimicked this phenomenon. Finally, CD45- EPCs predicted the overall and disease-free survival of stage I-III GC patients after radical resection.

CONCLUSIONS

The CD45- EPCs accumulated in GC tissues and metastatic LNs and promoted LN metastasis via the S100A8/9-induced hybrid E/M state of LECs, which was the specific mechanism of LN metastasis in the early stages of GC.

Current standards of lymphadenectomy in gastric cancer

Gastric cancer remains the 5th most common cancer and the 3rd most common cause of cancer mortality. Most patients diagnosed with gastric cancer still have a poor prognosis due to its advanced presentation at diagnosis, even in countries with developed screening programs. Surgery is the cornerstone of the treatment for gastric cancer, often combined with perioperative chemotherapy. Lymph node dissection is a crucial component of the surgical treatment of gastric cancer. D1 lymphadenectomy is currently recommended for early stage tumors. The extent of lymphadenectomy in advanced gastric cancer, however, is still a matter of debate between Eastern and Western surgeons. Although a D2 dissection is the current standard recommended by most guidelines, there might be a place for more limited dissections such as D1 + in selected cases. This evidence-based review will help defining the optimal lymphadenectomy for patients with gastric cancer.

Lymph node metastasis in cancer progression: molecular mechanisms, clinical significance and therapeutic interventions

Lymph nodes (LNs) are important hubs for metastatic cell arrest and growth, immune modulation, and secondary dissemination to distant sites through a series of mechanisms, and it has been proved that lymph node metastasis (LNM) is an essential prognostic indicator in many different types of cancer. Therefore, it is important for oncologists to understand the mechanisms of tumor cells to metastasize to LNs, as well as how LNM affects the prognosis and therapy of patients with cancer in order to provide patients with accurate disease assessment and effective treatment strategies. In recent years, with the updates in both basic and clinical studies on LNM and the application of advanced medical technologies, much progress has been made in the understanding of the mechanisms of LNM and the strategies for diagnosis and treatment of LNM. In this review, current knowledge of the anatomical and physiological characteristics of LNs, as well as the molecular mechanisms of LNM, are described. The clinical significance of LNM in different anatomical sites is summarized, including the roles of LNM playing in staging, prognostic prediction, and treatment selection for patients with various types of cancers. And the novel exploration and academic disputes of strategies for recognition, diagnosis, and therapeutic interventions of metastatic LNs are also discussed.

Complete mesogastric excision for gastric cancer: is it the future of gastric cancer surgery?

Gastric cancer remains undoubtedly one of the most common and deadly cancers worldwide. The global incidence shows wide geographic variation with a high prevalence in Asia. Besides that, there are evident differences in epidemiology, histopathology, tumor location, diagnosis and treatment strategy between east and west countries. Gastric cancer represents an aggressive disease, with many factors influencing its development and also recurrence after surgical resection. New knowledge of disease spread and new routes of metastases are now emerging and the 'novel' concept of complete mesogastric excision for gastric cancer is under consideration and debate. This article aims to analyze and highlight this new concept after a careful literature review, offering also a view toward the future.

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.

Predictive factors of lymphatic metastasis and evaluation of the Japanese treatment guidelines for endoscopic resection of early gastric cancer in a high-volume center in Perú

Purpose

This study aimed to identify the predictive factors of lymph node metastasis (LNM) in patients with early gastric cancer (EGC) and to evaluate the applicability of the Japanese treatment guidelines for endoscopic resection in the western population.

Methods

Five hundred-one patients with pathological diagnoses of EGC were included. Univariate and multivariate analyses were conducted to identify the predictive factors of LNM. EGC patients were distributed according to the indications for endoscopic resection of the Eastern guidelines. The incidence of LNM was evaluated in each group.

Results

From 501 patients with EGC, 96 (19.2%) presented LNM. In 279 patients with tumors with submucosal infiltration (T1b), 83 (30%) patients had LNM. Among 219 patients who presented tumors > 3 cm, 63 (29%) patients had LNM. Thirty-one percent of patients with ulcerated tumors presented LMN (33 out of 105). In 76 patients and 24 patients with lymphovascular and perineural invasion, the percentage of LMN was 84% and 87%, respectively. In the multivariate analysis, a tumor diameter >3 cm, submucosal invasion, lymphovascular, and perineural invasion were independent predictors of LMN in EGC. No patient with differentiated, non-ulcerated mucosal tumors presented LNM regardless of tumor size. Three of 17 patients (18%) with differentiated, ulcerated mucosal tumors and ≤ 3 cm presented LNM. No LNM was evidenced in patients with undifferentiated mucosal tumors and ≤ 2 cm.

Conclusions

The presence of LNM in Western EGC patients was independently related to larger tumors (>3 cm), submucosal invasion, lymphovascular and perineural invasion. The Japanese absolute indications for EMR are safe in the Western population. Likewise, Western patients with differentiated, non-ulcerated mucosal tumors, and larger than 2 cm are susceptible to endoscopic resection. Patients with undifferentiated mucosal tumors smaller than 2 cm presented encouraging results and ESD could be recommended only for selected cases.

Updates on global epidemiology, risk and prognostic factors of gastric cancer

Gastric cancer (GC) is defined as the primary epithelial malignancy derived from the stomach, and it is a complicated and heterogeneous disease with multiple risk factors. Despite its overall declining trend of incidence and mortality in various countries over the past few decades, GC remains the fifth most common malignancy and the fourth leading cause of cancer-related death globally. Although the global burden of GC has shown a significant downward trend, it remains severe in certain areas, such as Asia. GC ranks third in incidence and mortality among all cancer types in China, and it accounts for nearly 44.0% and 48.6% of new GC cases and GC-related deaths in the world, respectively. The regional differences in GC incidence and mortality are obvious, and annual new cases and deaths are increasing rapidly in some developing regions. Therefore, early preventive and screening strategies for GC are urgently needed. The clinical efficacies of conventional treatments for GC are limited, and the developing understanding of GC pathogenesis has increased the demand for new therapeutic regimens, including immune checkpoint inhibitors, cell immunotherapy and cancer vaccines. The present review describes the epidemiology of GC worldwide, especially in China, summarizes its risk and prognostic factors, and focuses on novel immunotherapies to develop therapeutic strategies for the management of GC patients.

Confusion and prospects for carcinogenesis of gastric adenoma and dysplasia: What is the correct answer currently?

There are differences in the diagnoses of superficial gastric lesions between Japan and other countries. In Japan, superficial gastric lesions are classified as adenoma or cancer. Conversely, outside Japan, the same lesion is classified as low-grade dysplasia (LGD), high-grade dysplasia, or invasive neoplasia. Gastric carcinogenesis occurs mostly de novo, and the adenoma-carcinoma sequence does not appear to be the main pathway of carcinogenesis. Superficial gastric tumors can be roughly divided into the APC mutation type and the TP53 mutation type, which are mutually exclusive. APC-type tumors have low malignancy and develop into LGD, whereas TP53-type tumors have high malignancy and are considered cancerous even if small. For lesions diagnosed as category 3 or 4 in the Vienna classification, it is desirable to perform complete en bloc resection by endoscopic submucosal dissection followed by staging. If there is lymphovascular or submucosal invasion after mucosal resection, additional surgical treatment of gastrectomy with lymph node dissection is required. In such cases, function-preserving curative gastrectomy guided by sentinel lymph node biopsy may be a good alternative.

Construction of a Prognostic Immune-Related LncRNA Risk Model for Gastric Cancer

Gastric cancer (GC) is one of the most common malignancies, and novel prognostic biomarkers for it are urgently required. This study is aimed at screening a group of immune-related lncRNAs (IRLs) in predicting the prognosis of GC patients. Genetic and clinical information from the 360 GC patients was included in this study. Eight IRLs in lncRNA-miRNA-mRNA network were screened out according to differential expression analysis. A novel risk score model with three IRLs (MIR4435-1HG, UCA1, and RP11-617F23.1) were identified, and patients were assigned to a high-risk group and a low-risk group. Patients in the low-risk group had a better prognosis. In addition, two nomograms were developed to predict the prognosis of GC. We evaluated the correlation between IRLs and the immune infiltration level of GC using TIMER. Furthermore, we verified that RP11-617F23.1 was significantly upregulated in human GC tissues compared with their adjacent tissues. And, patients with high RP11-617F23.1 expression in tumor tissues had poorer survival. In conclusion, we established a novel risk model based on IRLs for predicting the prognosis of GC. Meanwhile, a novel IRL, RP11-617F23.1, could serve as a predictor of prognosis for patients with GC.

Patients with gastroenteric tumor after upper abdominal surgery were more likely to require rescue analgesia than lower abdominal surgery

OBJECTIVES

To find out the reasons why patients still need to use rescue analgesics frequently after gastrointestinal tumor surgery under the patient-controlled intravenous analgesia (IV-PCA), and the different abdominal surgery patients using the difference of analgesics.

METHODS

A total of 970 patients underwent abdominal operation for gastrointestinal tumors were included. According whether patients used dezocine frequently for rescue analgesics within 2 days after surgery, they assigned into two groups: RAN group (Patients who did not frequently use rescue analgesia, 406 cases) and RAY group (Patients who frequently used rescue analgesia, 564 cases). The data collected included patient's characteristics, postoperative visual analogue scale (VAS), nausea and vomiting (PONV), and postoperative activity recovery time.

RESULTS

No differences were observed in the baseline characteristics. Compared with the RAN group, patients in the RAY group had a higher proportion of open surgery, upper abdominal surgery, VAS score at rest on the first 2 days after surgery and PONV, and a slower recovery of most postoperative activities. Under the current use of IV-PCA background, the proportion of rescue analgesics used by patients undergoing laparotomy and upper abdominal surgery was as high as 64.33% and 72.8%, respectively. Regression analysis showed that open surgery (vs laparoscopic surgery: OR: 2.288, 95% CI: 1.650-3.172) and the location of the tumor in the upper abdomen (vs lower abdominal tumor: OR: 2.738, 95% CI: 2.034-3.686) were influential factors for frequent salvage administration.

CONCLUSIONS

In our patient population, with our IV-PCA prescription for postoperative pain control, patient who underwent open upper abdominal surgery required more rescue postoperative analgesia.

Application of Machine Learning Algorithms to Predict Lymph Node Metastasis in Early Gastric Cancer

OBJECTIVE

This study aimed to establish the best early gastric cancer lymph node metastasis (LNM) prediction model through machine learning (ML) to better guide clinical diagnosis and treatment decisions.

METHODS

We screened gastric cancer patients with T1a and T1b stages from 2010 to 2015 in the Surveillance, Epidemiology and End Results (SEER) database and collected the clinicopathological data of patients with early gastric cancer who were treated with surgery at the Second Affiliated Hospital of Nanchang University from January 2014 to December 2016. At the same time, we applied 7 ML algorithms-the generalized linear model (GLM), RPART, random forest (RF), gradient boosting machine (GBM), support vector machine (SVM), regularized dual averaging (RDA), and the neural network (NNET)-and combined them with patient pathological information to develop the best prediction model for early gastric cancer lymph node metastasis. Among the SEER set, 80% were randomly selected to train the models, while the remaining 20% were used for testing. The data from the Second Affiliated Hospital were considered as the external verification set. Finally, we used the AUROC, F1-score value, sensitivity, and specificity to evaluate the performance of the model.

RESULTS

The tumour size, tumour grade, and depth of tumour invasion were independent risk factors for early gastric cancer LNM. Comprehensive comparison of the prediction model performance of the training set and test set showed that the RDA model had the best prediction performance (F1-score = 0.773; AUROC = 0.742). The AUROC of the external validation set was 0.73.

CONCLUSIONS

Tumour size, tumour grade, and depth of tumour invasion were independent risk factors for early gastric cancer LNM. ML predicted LNM risk more accurately, and the RDA model had the best predictive performance and could better guide clinical diagnosis and treatment decisions.

Significance of Lymph Node Metastasis in the Treatment of Gastric Cancer and Current Challenges in Determining the Extent of Metastasis

The stomach exhibits abundant lymphatic flow, and metastasis to lymph nodes is common. In the case of gastric cancer, there is a regularity to the spread of lymph node metastasis, and it does not easily metastasize outside the regional nodes. Furthermore, when its extent is limited, nodal metastasis of gastric cancer can be cured by appropriate lymph node dissection. Therefore, identifying and determining the extent of lymph node metastasis is important for ensuring accurate diagnosis and appropriate surgical treatment in patients with gastric cancer. However, precise detection of lymph node metastasis remains difficult. Most nodal metastases in gastric cancer are microscopic metastases, which often occur in small-sized lymph nodes, and are thus difficult to diagnose both preoperatively and intraoperatively. Preoperative nodal diagnoses are mainly made using computed tomography, although the specificity of this method is low because it is mainly based on the size of the lymph node. Furthermore, peripheral nodal metastases cannot be palpated intraoperatively, nodal harvesting of resected specimens remains difficult, and the number of lymph nodes detected vary greatly depending on the skill of the technician. Based on these findings, gastrectomy with prophylactic lymph node dissection is considered the standard surgical procedure for gastric cancer. In contrast, several groups have examined the value of sentinel node biopsy for accurately evaluating nodal metastasis in patients with early gastric cancer, reporting high sensitivity and accuracy. Sentinel node biopsy is also important for individualizing and optimizing the extent of uniform prophylactic lymph node dissection and determining whether patients are indicated for function-preserving curative gastrectomy, which is superior in preventing post-gastrectomy symptoms and maintaining dietary habits. Notably, advancements in surgical treatment for early gastric cancer are expected to result in individualized surgical strategies with sentinel node biopsy. Chemotherapy for advanced gastric cancer has also progressed, and conversion gastrectomy can now be performed after downstaging, even in cases previously regarded as inoperable. In this review, we discuss the importance of determining lymph node metastasis in the treatment of gastric cancer, the associated difficulties, and the need to investigate strategies that can improve the diagnosis of lymph node metastasis.

Management of acute kidney injury in gastrointestinal tumor: An overview

Gastrointestinal tumors remain a global health problem. Acute kidney injury (AKI) is a common complication during the treatment of gastrointestinal tumors. AKI can cause a decrease in the remission rate and an increase in mortality. In this review, we analyzed the causes and risk factors for AKI in gastrointestinal tumor patients. The possible mechanisms of AKI were divided into three groups: pretreatment, intrafraction and post-treatment causes. Treatment and prevention measures were proposed according to various factors to provide guidance to clinicians and oncologists that can reduce the incidence of AKI and improve the quality of life and survival rate of gastrointestinal tumor patients.

Life prognosis of sentinel node navigation surgery for early-stage gastric cancer: Outcome of lymphatic basin dissection

BACKGROUND

Lymphatic basin dissection is a sentinel node biopsy method that is specific for gastric cancer. In this method, the dyed lymphatic system is dissected en bloc, and sentinel nodes are identified at the back table (ex vivo). Even with lymphatic basin dissection, blood flow to the residual stomach can be preserved, and function-preserving curative gastrectomy can be performed. The oncological safety of function-preserving curative gastrectomy combined with lymphatic basin dissection has not yet been fully investigated. We hypothesized that the oncological safety of sentinel node navigation surgery (SNNS) is not inferior to that of the guidelines.

AIM

To investigate the life prognosis of SNNS for gastric cancer in comparison with guidelines surgery.

METHODS

This was a retrospective cohort study. Patients were selected from gastric cancer patients who underwent sentinel node biopsy from April 1999 to March 2016. Patients from April 1999 to August 2008 were from the Department of Surgery II, Kanazawa University Hospital, and patients from August 2009 to March 2016 were from the Department of Surgical Oncology, Kanazawa Medical University Hospital. Patients who were diagnosed with gastric cancer, which was preoperatively diagnosed as superficial type (type 0), 5 cm or less in length, clinical T1-2 and node negative, and underwent various gastrectomies guided by sentinel node navigation were retrospectively collected. The overall survival (OS) and relapse-free survival (RFS) of these patients (SNNS group) were investigated. Patients with gastric cancer of the same stage and who underwent guidelines gastrectomy with standard nodal dissection were also selected as the control group.

RESULTS

A total of 239 patients in the SNNS group and 423 patients in the control group were included. Pathological nodal metastasis was observed in 10.5% and 10.4% of the SNNS and control groups, respectively. The diagnostic abilities of sentinel node biopsy were 84% and 98.6% for sensitivity and accuracy, respectively. In the SNNS group, 81.6% of patients underwent modified gastrectomy or function-preserving curative gastrectomy with lymphatic basin dissection, in which the extent of nodal dissection was further reduced compared to the guidelines. The OS rate in the SNNS group was 96.8% at 5 years and was significantly better than 91.3% in the control group (P = 0.0014). The RFS rates were equal in both groups. After propensity score matching, there were 231 patients in both groups, and the cumulative recurrence rate was 0.43% at 5 years in the SNNS group and 1.30% in the control group, which was not statistically different.

CONCLUSION

The oncological safety of patients who undergo gastrectomy guided by sentinel node navigation is not inferior to that of the guidelines surgery.

nPTD classification: an updated classification of gastric cancer location for function preserving gastrectomy based on physiological lymphatic flow

BACKGROUND

The correlation between tumor location and lymphatic flow distribution in gastric cancer has been previously reported, and PTD (Proximal - Transitional - Distal) classification was proposed. Our group updated and developed the nPTD classification.

METHOD

We retrospectively studied gastric cancer patients who underwent the dye method sentinel node biopsy from 1993 to 2020. The inclusion criteria were a single lesion type 0 cancer of ≤5 cm in the long axis, clinically node-negative, and invasion within the proper muscle layer pathologically. In this study, the distribution of dyed lymphatic flow was evaluated for each occupied area of the tumor.

RESULTS

We included 416 patients in this study. The tumors located in the watershed of the right and left gastroepiploic arteries near greater curvature had extensive lymphatic flow; therefore, a newly circular region with a diameter of 5 cm is set on the watershed of the greater curvature between P and T zone as the 'n' zone. In addition, for cancers located in the lesser P curvature, lymphatic flow to the greater curvature was not observed. Therefore, the P zone was divided into two: the lesser curvature side (PL) and the greater curvature side (PG).

CONCLUSIONS

The advantage of the nPTD classification is that it provides not only proper nodal dissection but also adequate function-preserving gastrectomy. If the tumor is localized within the PL, the proximal gastrectomy resection area can be further reduced. In contrast, for cancers located in the 'n' zone, near-total gastrectomy is required because of the extensive lymphatic flow.

Risk Factors of Lymph Node Metastasis and Its Prognostic Significance in Early Gastric Cancer: A Multicenter Study

Background

Early gastric cancer (EGC) is invasive gastric cancer that invades no deeper than the submucosa, regardless of lymph node metastasis (LNM). It is mainly treated by surgery. Recently, the resection range of EGC has been minimized, but cancer recurrence and overall survival in some patients should be given high status. LNM is an important indicator of prognosis and treatment in gastric cancer. The law of the number and location of metastatic lymph nodes in EGC is not yet clear. Therefore, we aimed to identify the risk factors of LNM in radically resected EGC and guide treatment.

Methods

The clinicopathological factors of 611 patients with EGC were retrospectively analyzed in six hospitals between January 2010 and December 2016. The relationship between clinicopathological factors and LNM, as well as their prognostic significance, were analyzed by univariate and multivariate analyses.

Results

The rate of LNM was 20.0% in the 611 EGC patients. The depth of invasion, differentiation type, tumor diameter, morphological ulceration, and lymphovascular invasion were independent risk factors for LNM (P<0.05) by logistic regression analysis. Tumor location in the proximal third of the stomach and morphological ulceration were significant factors for group 2 LNM. Moreover, the 5-year survival rate was 94.9% for patients with no positive nodes, 88.5% for patients with 1-2 positive nodes, 64.3% for patients with 3-6 positive nodes, and 41.8% for patients with >6 metastatic nodes. Interestingly, the 7-year risk of relapse diminished for patients with no LNM or retrieved no less than 15 lymph nodes.

Conclusions

Fifteen lymph node dissection and D2 radical operation are the surgical options in case of high risk factors for LNM. Extended lymph node dissection (D2+) is recommended for morphological ulceration or disease located in the proximal third of the stomach due to their high rate of group 2 LNM. Furthermore, LNM is a significant prognostic factor of EGC. Moreover, lymph nodes can also play a significant role in the chemotherapeutic and radiotherapy approach for non-surgical patients with EGC.

Assessment on the Prognostic Validity of Dissected and Positive Lymph Node Counts and Lymph Node Ratio in Patients with Gastric Cancer: A Multi-central Cohort Study

Background: Adequate treatment for all resectable early gastric cancers (EGCs) is gastrectomy with regional lymphadenectomy. The number of positive resected lymph nodes during lymphadenectomy can be a reliable predictor of survival of GC. Objectives: We aimed at assessing the prognostic significance of Dissected Lymph Node Count (DLNC), positive LNC (PLNC), and Lymph Node Ratio (LNR) in patients with EGC. Methods: In the current retrospective cohort, 201 patients with resectable EGC were included. Demographic variables, clinicopathological characteristics of tumors (including numbers of total dissected nodes and positive, negative nodes), history of receiving adjuvant cancer therapies, and 1- and 5-year survivals were noted. Results: DLNC, PLNC, and LNR were associated with differentiation and depth of tumor, lymph node status, and risk of death (P-value for all < 0.05). There was no correlation between either of these measures with preoperative symptoms, lymphovascular invasion, and recurrence. DLNC, PLNC, and LNR showed prognostic significance only in patients, who did not receive comprehensive therapy (P-value < 0.001 for all). A significantly higher LNR was seen in patients with more than 1-year survival compared to others (P-value = 0.011). A significantly lower DLNC and higher PLNC were seen in patients, who survived over 5 years (P-value of 0.002 and 0.047, respectively). Conclusions: LNR, DLNC, and PLNC are significant prognostic factors for EGC. According to our findings, choosing the optimal approach, through which fewer negative lymph nodes are dissected, is crucial in increasing overall survival and extended lymphadenectomy cannot necessarily benefit patients.

Robotic versus laparoscopic gastrectomy for gastric cancer: The largest meta-analysis

BACKGROUND

Minimally invasive surgery (MIS) has been increasingly used in the treatment of gastric cancer (GC). Laparoscopic gastrectomy (LG) has shown several advantages over open surgery in dealing with GC, although it is still considered a demanding procedure. Robotic gastrectomy (RG) is now being employed with increased frequency worldwide and has been reported to overcome some limitations of conventional LG. The aim of this updated meta-analysis is to compare surgical and oncological outcomes of RG versus LG for gastric cancer.

MATERIALS AND METHODS

A systematic review and meta-analysis was conducted using the PubMed, MEDLINE and Cochrane library database of published studies comparing RG and LG up to March 2020. The evaluated end-points were intra-operative, post-operative and oncological outcomes. Dichotomous data were calculated by odds ratio (OR) and continuous data were calculated by mean difference (MD) with 95% confidence intervals (95% CI), and a random-effect model was always applied.

RESULTS

Forty retrospective studies describing 17,712 patients met the inclusion criteria. With respect to surgical outcomes, robotic compared with laparoscopic gastrectomy was associated with higher operating time [MD 44.73, (95%CI 36.01, 53.45) p < 0.00001] and less intraoperative blood loss [MD -18.24, (95%CI -25.21, -11.26) p < 0.00001] and lower rate of surgical complication in terms of Dindo-Clavien ≥ 3 classification [OR 0.66, (95%CI 0.49, 0.88) p = 0.005]. With respect to oncological outcomes, the RG group showed a significantly increased mean number of retrieved lymph nodes [MD 1.84, (95%CI 0.84, 2.84) p = 0.0003], but mean proximal and distal resection margin distance and the recurrence rate were not significantly different between the two approaches.

CONCLUSIONS

With respect to safety, technical feasibility and oncological adequacy, robotic and laparoscopic groups were comparable, although the robotic approach seems to achieve better short-term surgical outcomes. Moreover, a higher rate of retrieved lymph nodes was observed in the RG group.

Severity of postgastrectomy syndrome and quality of life after advanced gastric cancer radical gastrectomy

It has previously been suggested that postgastrectomy syndrome (PGS) is more severe in patients after surgery for advanced gastric cancer than in patients with early gastric cancer. Using the postgastrectomy syndrome assessment scale-45 (PGSAS-45), the present study aimed to determine whether PGS for postgastrectomy patients, in Kanazawa Medical University Hospital, with advanced gastric cancer was more severe than for patients with early gastric cancer. A questionnaire survey was conducted using PGSAS-45 for curative gastric cancer gastrectomy cases at Kanazawa Medical University Hospital. The questionnaire data were combined with patient background data, anonymized and moved to an unlinked file for patient privacy. Using this dataset, non-recurrent cases of distal partial gastrectomy were extracted and divided into two groups, stage IA or IB patients (group E), and stage IIA or higher (group A). The main outcome measures (MOMs) of PGSAS-45 were compared between the two groups. The participants in the present study included 35 cases in group E and 22 cases in group A. The results of a univariate analysis to compare the MOMs between the two groups showed that only the dumping subscale was significantly different in group A and was judged to be caused by the underlying bias of the background factor. There were no MOMs with significant differences in the pathological stage based on multiple regression analyses. In cases of distal partial gastrectomy, the PGS and quality of life (QoL) of patients following advanced gastric cancer surgery were similar to those of patients with early gastric cancer. The standardized treatment for advanced gastric cancer did not induce notable postoperative failures, and QoL was not impaired. In contrast, for early-stage gastric cancer cases, the present study suggests that it is necessary to distinguish metastasis-negative cases to indicate an appropriate, function-preserving curative gastrectomy.

Integrating tumor and nodal radiomics to predict lymph node metastasis in gastric cancer

BACKGROUND

To develop and validate a radiomics method via integrating tumor and lymph node radiomics for the preoperative prediction of lymph node (LN) status in gastric cancer (GC).

MATERIALS AND METHODS

We retrospectively collected 170 contrast-enhanced abdominal CT images from GC patients. Five times repeated random hold-out experiment was employed. Tumor and nodal radiomics features were extracted from each individual tumor and LN respectively, and then multi-step feature selection was performed. The optimal tumor and nodal features were selected using Pearson correlation analysis and sequential forward floating selection (SFFS) algorithm. After feature fusion, the SFFS algorithm was used to develop radiomics signatures. The performance of the radiomics signatures developed based on logistic regression classifier was further analyzed and compared using the area under the receiver operating characteristic curve (AUC).

RESULTS

The AUC values, reported as mean ± standard deviation, were 0.9319 ± 0.0129 and 0.8546 ± 0.0261 for the training and validation cohorts respectively. The radiomic signatures could predict LN status, especially in T2-stage, diffuse-type and moderately/well differentiated GC. After integrating clinicopathologic information, the radiomic-clinicopathologic model (training cohort, 0.9432 ± 0.0129; validation cohort, 0.8764 ± 0.0322) showed a better discrimination capability than other radiomics models and clinicopathologic model. The radiomic-clinicopathologic model also showed superior performance to the gastroenterologist' decision in all experiments, and outperformed the radiologist in some experiments.

CONCLUSION

Our proposed method presented good predictive performance and great potential for predicting LNM in GC. As a noninvasive preoperative prediction tool, it can be helpful for guiding the prognosis and treatment decision-making in GC patients.

Gastric Cancer: Epidemiology, Risk Factors, Classification, Genomic Characteristics and Treatment Strategies

Gastric cancer (GC) is one of the most common malignancies worldwide and it is the fourth leading cause of cancer-related death. GC is a multifactorial disease, where both environmental and genetic factors can have an impact on its occurrence and development. The incidence rate of GC rises progressively with age; the median age at diagnosis is 70 years. However, approximately 10% of gastric carcinomas are detected at the age of 45 or younger. Early-onset gastric cancer is a good model to study genetic alterations related to the carcinogenesis process, as young patients are less exposed to environmental carcinogens. Carcinogenesis is a multistage disease process specified by the progressive development of mutations and epigenetic alterations in the expression of various genes, which are responsible for the occurrence of the disease.

Feedback regulation between phosphatidylinositol-3,4,5-trisphosphate dependent Rac exchange factor 1 and transforming growth factor β1 and prognostic value in gastric cancer

BACKGROUND

Phosphatidylinositol-3,4,5-trisphosphate dependent Rac exchange factor 1 (PREX1) was reported to be overexpressed in some cancers and involved in cancer development, but its expression and significance in gastric cancer remain unclear.

AIM

To evaluate the expression of PREX1 in gastric cancer and its significance in the development of gastric cancer, especially to evaluate the potential mechanism of PREX1 in gastric cancer.

METHODS

Bioinformatic analysis was performed in order to examine the expression of PREX1 in gastric cancer. The relationship between the survival rate of gastric cancer patients and PREX1 expression was assessed by Kaplan Meier portal. The Gene Set Enrichment Analysis and the correlation between PREX1 and transforming growth factor (TGF) β1 pathway-related mediators were evaluated by cBioPortal for Cancer Genomics. Western blotting and reverse transcriptase polymerase chain reaction assay were used to test the role of TGFβ1 on the expression of PREX1. Western blotting and dual-luciferase reporter system was used to evaluate the effect of PREX1 on the activation of TGFβ1 pathway. Wound healing and Transwell assay were used to assess the effect of PREX1 on the metastasis activity of gastric cancer cells.

RESULTS

PREX1 was overexpressed in the gastric tumors, and the expression levels were positively associated with the development of gastric cancer. Also, the high expression of PREX1 revealed poor prognosis, especially for those advanced and specific intestinal gastric cancer patients. PREX1 was closely involved in the positive regulation of cell adhesion and positively correlated with TGFβ1-related mediators. Furthermore, TGFβ1 could induce the expression of PREX1 at both the protein and mRNA level. Also, PREX1 could activate the TGFβ1 pathway. The induced PREX1 could increase the migration and invasion activity of gastric cancer cells.

CONCLUSION

PREX1 is overexpressed in gastric cancer, and the high level of PREX1 predicts poor prognosis. PREX1 is closely associated with TGFβ signaling and promotes the metastasis of gastric cancer cells.