The risk of lymph node metastases in 3951 surgically resected mucosal gastric cancers: implications for endoscopic resection

Effectiveness and safety of newly introduced endoscopic submucosal dissection in a Western center: a real-life study

OBJECTIVES

Endoscopic submucosal dissection (ESD) is a minimally invasive technique for the resection of superficial gastrointestinal lesions, providing high rates of 'en bloc' and R0 resection. East-West differences in ESD quality indicators have been reported. This study aims to assess feasibility, effectiveness, and safety of ESD for the treatment of superficial gastrointestinal (GI) lesions in a Western cohort.

METHODS

Consecutive patients undergoing ESD at one Italian endoscopic referral center from September 2018 to March 2020 were included in this prospective study. Primary outcomes were technical success, R0 resection rate, curative resection rate, and adverse events (AEs).

RESULTS

In total 111 patients (111 lesions) undergoing ESD were included. Anatomic site of the lesions was rectum in 56.8%, colon in 13.5%, stomach in 24.3%, and esophagus in 5.4% of cases, respectively. For upper GI procedures, technical success was 100%, and R0 and curative resection rates were 84.8% and 78.8%, respectively. For colorectal procedures, technical success was 98.7%, R0 and curative resection rates were 88.5% and 84.6%, respectively. Major AEs were reported in 12 cases (10.8%).

CONCLUSION

The introduction of ESD in a Tertiary Center is feasible, effective, and safe, and should be taken into consideration for the treatment of superficial GI lesions requiring 'en bloc' resection.

Comparable long-term survival outcomes after endoscopic and gastrectomy treatment of pT1acN0M0 gastric adenocarcinoma in patients who met the expanded criteria

BACKGROUND

Whether the Western pT1acN0M0 gastric cancer (GC) patients who met the Japanese expanded criteria could be the candidates for endoscopic treatment (ET) remains unclear because of unknown long-term survival outcomes.

METHODS

A retrospective cohort study using data from the Surveillance, Epidemiology, and End Results (SEER) program was performed. The survival differences between pT1acN0M0 gastric adenocarcinoma patients who received ET or gastrectomy treatment (GT) were evaluated using multivariate survival analysis.

RESULTS

A total of 314 pT1acN0M0 gastric adenocarcinoma patients who met the expanded criteria were included, 46 patients received ET and 268 patients received GT. pT1acN0M0 gastric adenocarcinoma patients met the expanded criteria underwent ET experienced a similar hazard of cancer-specific death compared with those underwent GT both in the multivariate Cox survival analysis (adjusted hazard ratio [HR]; 1.18, 95% confidence interval [CI] 0.40-3.49; P = 0.766) and the multivariate competing risk model (subdistribution HR [SHR], 1.12, 95% CI 0.38-3.29; P = 0.845). The result that pT1acN0M0 gastric adenocarcinoma patients met the expanded criteria underwent ET experienced comparable survival outcomes to those who underwent GT did not change even compared with those who underwent GT with > 15 lymph nodes examined (adjusted HR, 1.55, 95% CI 0.44-5.49; P = 0.499; SHR, 1.47, 95% CI 0.44-4.88; P = 0.532).

CONCLUSIONS

The ET can be considered in Western pT1acN0M0 gastric adenocarcinoma patients who met the Japanese expanded criteria. However, a prospective study should be warranted.

Endoscopic Resection of Undifferentiated Early Gastric Cancer

Endoscopic resection (ER) is widely performed for early gastric cancer (EGC) with a negligible risk of lymph node metastasis (LNM) in Eastern Asian countries. In particular, endoscopic submucosal dissection (ESD) leads to a high en bloc resection rate, enabling accurate pathological evaluation. As undifferentiated EGC (UD-EGC) is known to result in a higher incidence of LNM and infiltrative growth than differentiated EGC (D-EGC), the indications for ER are limited compared with those for D-EGC. Previously, clinical staging as intramucosal UD-EGC ≤2 cm, without ulceration, was presented as 'weakly recommended' or 'expanded indications' for ER in the guidelines of the United States, Europe, Korea, and Japan. Based on promising long-term outcomes from a prospective multicenter study by the Japan Clinical Oncology Group (JCOG) 1009/1010, the status of this indication has expanded and is now considered 'absolute indications' in the latest Japanese guidelines published in 2021. In this study, which comprised 275 patients with UD-EGC (cT1a, ≤2 cm, without ulceration) treated with ESD, the 5-year overall survival (OS) was 99.3% (95% confidence interval, 97.1%-99.8%), which was higher than the threshold 5-year OS (89.9%). Currently, the levels of evidence grades and recommendations for ER of UD-EGC differ among Japan, Korea, and Western countries. Therefore, a further discussion is warranted to generalize the indications for ER of UD-EGC in countries besides Japan.

Establishment and Validation for Predicting the Lymph Node Metastasis in Early Gastric Adenocarcinoma

Lymph node metastasis (LNM) is considered to be one of the important factors in determining the optimal treatment for early gastric cancer (EGC). This study aimed to develop and validate a nomogram to predict LNM in patients with EGC. A total of 842 cases from the Surveillance, Epidemiology, and End Results (SEER) database were divided into training and testing sets with a ratio of 6 : 4 for model development. Clinical data (494 patients) from the hospital were used for external validation. Univariate and multivariate logistic regression analyses were used to identify the predictors using the training set. Logistic regression, LASSO regression, ridge regression, and elastic-net regression methods were used to construct the model. The performance of the model was quantified by calculating the area under the receiver operating characteristic curve (AUC) with 95% confidence intervals (CIs). Results showed that T stage, tumor size, and tumor grade were independent predictors of LNM in EGC patients. The AUC of the logistic regression model was 0.766 (95% CI, 0.709-0.823), which was slightly higher than that of the other models. However, the AUC of the logistic regression model in external validation was 0.625 (95% CI, 0.537-0.678). A nomogram was drawn to predict LNM in EGC patients based on the logistic regression model. Further validation based on gender, age, and grade indicated that the logistic regression predictive model had good adaptability to the population with grade III tumors, with an AUC of 0.803 (95% CI, 0.606-0.999). Our nomogram showed a good predictive ability and may provide a tool for clinicians to predict LNM in EGC patients.

Endoscopic submucosal dissection for superficial gastrointestinal lesions: European Society of Gastrointestinal Endoscopy (ESGE) Guideline - Update 2022

ESGE recommends that the evaluation of superficial gastrointestinal (GI) lesions should be made by an experienced endoscopist, using high definition white-light and chromoendoscopy (virtual or dye-based).ESGE does not recommend routine performance of endoscopic ultrasonography (EUS), computed tomography (CT), magnetic resonance imaging (MRI), or positron emission tomography (PET)-CT prior to endoscopic resection.ESGE recommends endoscopic submucosal dissection (ESD) as the treatment of choice for most superficial esophageal squamous cell and superficial gastric lesions.For Barrett's esophagus (BE)-associated lesions, ESGE suggests the use of ESD for lesions suspicious of submucosal invasion (Paris type 0-Is, 0-IIc), for malignant lesions > 20 mm, and for lesions in scarred/fibrotic areas.ESGE does not recommend routine use of ESD for duodenal or small-bowel lesions.ESGE suggests that ESD should be considered for en bloc resection of colorectal (but particularly rectal) lesions with suspicion of limited submucosal invasion (demarcated depressed area with irregular surface pattern or a large protruding or bulky component, particularly if the lesions are larger than 20 mm) or for lesions that otherwise cannot be completely removed by snare-based techniques.ESGE recommends that an en bloc R0 resection of a superficial GI lesion with histology no more advanced than intramucosal cancer (no more than m2 in esophageal squamous cell carcinoma), well to moderately differentiated, with no lymphovascular invasion or ulceration, should be considered a very low risk (curative) resection, and no further staging procedure or treatment is generally recommended.ESGE recommends that the following should be considered to be a low risk (curative) resection and no further treatment is generally recommended: an en bloc R0 resection of a superficial GI lesion with superficial submucosal invasion (sm1), that is well to moderately differentiated, with no lymphovascular invasion, of size ≤ 20 mm for an esophageal squamous cell carcinoma or ≤ 30 mm for a stomach lesion or of any size for a BE-related or colorectal lesion, and with no lymphovascular invasion, and no budding grade 2 or 3 for colorectal lesions.ESGE recommends that, after an endoscopically complete resection, if there is a positive horizontal margin or if resection is piecemeal, but there is no submucosal invasion and no other high risk criteria are met, this should be considered a local-risk resection and endoscopic surveillance or re-treatment is recommended rather than surgery or other additional treatment.ESGE recommends that when there is a diagnosis of lymphovascular invasion, or deeper infiltration than sm1, or positive vertical margins, or undifferentiated tumor, or, for colorectal lesions, budding grade 2 or 3, this should be considered a high risk (noncurative) resection, and complete staging and strong consideration for additional treatments should be considered on an individual basis in a multidisciplinary discussion.ESGE recommends scheduled endoscopic surveillance with high definition white-light and chromoendoscopy (virtual or dye-based) with biopsies of only the suspicious areas after a curative ESD.

Lymph node involvement in gastric adenocarcinoma

BACKGROUND

Endoscopic management of early gastric cancer is limited by the risk of lymph node metastasis. We aimed to examine the incidence and predictors of nodal metastasis in early gastric adenocarcinoma in a large national US cohort.

METHODS

Cases were abstracted from the National Cancer Database from 2004 to 2016. The incidence and predictors of lymph node involvement for patients with Tis, T1a, and T1b tumors were examined.

RESULTS

A total of 202,216 cases of gastric adenocarcinoma were identified in the NCDB. Cases with unknown patient or tumor characteristics, presence of other cancers, and prior neoadjuvant chemotherapy or radiotherapy were excluded. 1839 cases of Tis, T1a, and T1b tumors were identified. Lymph node metastases were present in 18.1% of patients. Lymphovascular invasion (LVI), high-grade histology, stage T1b, and larger size (> 3 cm) were independently associated with an increased risk of nodal metastasis on multivariate analysis (P < 0.05). The presence of LVI was the strongest predictor of nodal metastasis with an OR (95% CI) of 5.7 (4.3-7.6), P < 0.001. No lymph node metastasis was found in any Tis tumors. Small T1a low-grade tumors with no LVI had a low risk of nodal metastasis (0.6% < 2 cm and 0.9% < 3 cm).

CONCLUSION

In this large national cohort, size, lymphovascular invasion, higher grade histology, and T stage were independently associated with lymph node metastasis. For patients with low-grade tumors, < 3 cm, without lymphovascular invasion, the risk of nodal involvement was very low, suggesting that this Western cohort could be considered for endoscopic resection.

Regional lymph node recurrence without intragastric lesions after curative endoscopic resection of early gastric cancer meeting the absolute indications of endoscopic resection: A case report

RATIONALE

With the increase of gastric cancer surveillance and endoscopic resection techniques, the number of endoscopic resections being performed for the treatment of early gastric cancer in East Asian countries has been increasing. Previously, endoscopic resection has been limited to only differentiated type intramucosal cancers which had a diameter ≤2.0 cm, provided there was no evidence of ulceration and lymphovascular invasion, known as absolute indications. And recently, indications for endoscopic resection have been expanded to include even more cases.

PATIENT CONCERNS

A 57-year-old female, who had undergone curative endoscopic submucosal dissection for early gastric cancer under the absolute indications for endoscopic resection 5 years prior, was referred to the department of general surgery with metastatic perigastric lymph nodes without intragastric lesions.

DIAGNOSIS

Computed tomography scan revealed the presence of a few enlarged lymph nodes at the distal part of the lesser curvature of the stomach. And positron emission tomography scan further revealed the presence of two hypermetabolic lymph nodes near the common hepatic artery, suggestive of metastatic lymph nodes.

INTERVENTIONS

Laparoscopic distal gastrectomy and Roux-en-Y gastrojejunostomy with D2 lymph node dissection were performed.

OUTCOMES

Final pathology report revealed the absence of any residual carcinoma in the stomach. However lymphovascular invasion of omental fat, and 3 out of 29 perigastric lymph nodes harvested had metastatic adenocarcinoma.

LESSONS

The case demonstrates that regional lymph node recurrence without intragastric lesions after curative resection of early gastric cancer meeting the absolute indications for endoscopic resection is possible even 5 years after resection of the primary lesion.

Surgical technique of suprapancreatic D2 lymphadenectomy focusing on the posterior hepatic plexus for advanced gastric cancer

PURPOSE

Although D2 lymphadenectomy is currently considered a standard procedure for advanced gastric cancer (GC) worldwide, there is room for discussion about the appropriate range of suprapancreatic D2 lymphadenectomy. Focusing on the posterior hepatic plexus (PHP), which is not well recognized, we developed a surgical technique of suprapancreatic D2 lymphadenectomy, which we have called PHP-D2, and its short-term and long-term efficacies were evaluated in comparison with non-PHP-D2.

METHODS

GC patients who underwent distal gastrectomy with D2 lymphadenectomy between July 2006 and May 2013 were enrolled, from which patients who had peritoneal metastasis and/or were peritoneal cytology-positive during surgery were excluded. Their medical records were retrospectively reviewed.

RESULTS

Ninety-two patients (non-PHP-D2: 48, PHP-D2: 44) were enrolled. Shorter operation time (330 min vs 275 min, p < 0.0001) and less blood loss (290 mL vs 125 mL, p < 0.0001) were observed in PHP-D2, and no pancreatic fistulas were observed in PHP-D2. More lymph nodes of #11p (1 vs 1.5, p = 0.0328) and #12a lymph nodes (0 vs 1, p = 0.0034) were retrieved in PHP-D2, with no significant differences in #8a and #9 lymph nodes. Lymphatic recurrence was significantly less in PHP-D2 (p = 0.0166), and univariate and multivariate analyses showed that non-PHP-D2 was a significant risk factor for lymphatic recurrence (p = 0.0158), although there were no significant differences between non-PHP-D2 and PHP-D2 in 5-year overall survival and 5-year relapse-free survival.

CONCLUSION

PHP-D2 was a safe and feasible procedure that had the potential to reduce lymphatic recurrence, and it can be a standard procedure of D2 lymphadenectomy for advanced GC.

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.

Clinicopathological significance of primitive phenotypes in early gastric cancer with differentiated histology

Background

Certain gastric cancers exhibit some primitive phenotypes, which may indicate a high malignancy. In histologically differentiated early gastric cancer (EGC), the presence and the clinicopathological significance of the primitive phenotype remain unclear.

Methods

Using immunohistochemical staining we detected the expression of three primitive phenotypic markers SALL4, Glypican-3(GPC3), and AFP in whole tissue sections of differentiated EGC (gastrectomy specimens, n = 302). For those cases with primitive phenotypes, we analyzed their clinicopathological features and evaluated whether the criteria for endoscopic resection were met.

Results

We found that 9.3% (28/302) of all differentiated EGC cases have primitive phenotypes, and most of these cases (25/28) exhibit a histomorphology similar to conventional differentiated EGC. Patients with primitive phenotypes had a deeper invasion, a higher rate of ulcer and lymphatic invasion than cases without primitive phenotype. Moreover, patients with primitive phenotypes displayed a significantly higher frequency of LNM than those without (57.1% vs 8.8%, P < 0.001). Multivariate analysis revealed that presence of primitive phenotypes was an independent risk factor for LNM (P = 0.001, HR 6.977, 95% CI: 2.199–22.138). Interestingly, we found 2 cases with primitive phenotypes developed LNM, and they both met the expanded indications of endoscopic resection for differentiated EGC.

Conclusions

A small number of differentiated EGC have primitive phenotypes, which were closely related to LNM and were an independent risk factor for LNM. Given its highly aggressive behavior, differentiated EGC with primitive phenotypes should be evaluated with stricter criteria before endoscopic resection, or considered to give an additional surgical operation after endoscopic resection.

Adenocarcinoma indiferenciado como factor predictor de metástasis ganglionares en cáncer gástrico

Introducción. El grado de diferenciación celular en el estudio histopatológico del adenocarcinoma gástrico está descrito como un factor pronóstico determinante en el comportamiento clínico del tumor. El adenocarcinoma gástrico indiferenciado es considerado una variante agresiva de mal pronóstico, que se correlaciona con una alta tasa de metástasis ganglionares. Métodos. Estudio prospectivo descriptivo de una serie de casos en el cual se analizan los pacientes con adenocarcinoma gástrico indiferenciado, que fueron llevados a cirugía radical con gastrectomía y linfadenectomía DII y su correlación con la presencia de metástasis ganglionares en un período de dos años. Resultados. De enero de 2018 a enero de 2020 se recolectaron en la base de datos 113 pacientes con adenocarcinoma gástrico a quienes se les practicó gastrectomía total, disección ganglionar DII y reconstrucción esofagoyeyunal terminolateral con técnica de Orr más Y de Roux. Fueron clasificados histológicamente como adenocarcinoma gástrico indiferenciado 41 pacientes (36,3 %). La edad promedio de este grupo fue de 56 años con un rango entre 28-92 años. De ellos 30 fueron hombres (73 %) y 11 mujeres (27 %). El número promedio de ganglios linfáticos analizados por espécimen fue de 24. De los 41 pacientes con adenocarcinoma gástrico indiferenciado, 35 (85 %) tuvieron metástasis ganglionares, con 382 ganglios positivos en total, con un rango entre 1-38 y un promedio de 11 ganglios linfáticos positivos por espécimen. Discusión. En esta serie el adenocarcinoma gástrico indiferenciado se presentó en el 36,3 % de los casos y se correlacionó con un 85 % de presencia de metástasis ganglionares en estadios T3-T4.

Physalin B inhibits cell proliferation and induces apoptosis in undifferentiated human gastric cancer HGC-27 cells

BACKGROUND

Physalin B (PB) from Physalis angulata L. (Solanaceae) is a naturally occurring secosteroid with multiple biological activities, including anti-inflammatory and anticancer activity. However, PB's effects and mechanisms in human gastric cancer (GC) cells are not well characterized.

METHODS

The undifferentiated GC cell line HGC-27 and semi-differentiated GC cell line SGC-7901 were treated with PB. Cell counting kit-8 (CCK-8) and colony formation assays were performed to evaluate cell viability. Apoptosis and the cell cycle were assessed by Annexin V/PI and PI/RNase DNA staining assays, respectively, and Western blotting was used to evaluate the expression of a protein.

RESULTS

PB significantly inhibited the proliferation of HGC-27 cells in a dose- and time-dependent manner. Moreover, PB induced G0/G1 cycle arrest and caspase-dependent apoptosis of HGC-27 cells. Cleaved caspases 8, 3, and 7, poly(ADP)-ribose polymerase (PARP), and the cyclin-dependent kinase (CDK) inhibitor p-Chk2 was induced by PB in HGC-27 cells, while the cell cycle-related proteins cyclin D1, cyclin D3, CDK4, CDK6, cyclin E, and phosphorylated retinoblastoma tumor suppressor protein (p-Rb) were downregulated in a dose-dependent manner.

CONCLUSIONS

PB inhibits proliferation via cyclin-dependent kinase and induces caspase-dependent apoptosis in HGC-27 cells, suggesting that PB might be a novel and effective agent for undifferentiated GC therapy.

Preoperative imaging evaluation of the absolute indication criteria for endoscopic submucosal dissection in early gastric cancer patients

Introduction

Gastric cancer (GC) is a common malignant tumor with a high mortality rate.

Aim

To determine the accuracy of preoperative imaging information obtained from the combined use of general gastroscopy (GS), endoscopic ultrasonography (EUS), and multi-detector computed tomography (MDCT) regarding absolute indication of endoscopic submucosal dissection (ESD) in early gastric cancer (EGC).

Material and methods

The relationship between clinical features of 794 EGC patients and lymph node metastasis (LNM) was analyzed. Multivariate logistic regression analysis was used to investigate the risk factors for LNM. Additionally, the accuracy of diagnosis of imaging techniques for ESD indications was determined by receiver operating characteristic (ROC) analysis.

Results

Data showed that tumor size > 2 cm (p = 0.0071), T1b stage (p < 0.0001), undifferentiated histology (p < 0.0001), and vascular invasion (p = 0.0007) were independent risk factors for LNM in patients with EGC. Indications for ESD have a specificity of 100% for the diagnosis of patients with LNM. Additionally, the diagnostic efficacy of the use of GS, EUS, and MDCT in identifying node positive status, T1a disease, tumor size ≤ 2 cm, and ulceration was found to be moderate with area under the curve (AUC) of receiver operating characteristic curve (ROC) of 0.71, 0.64, 0.72, and 0.68, respectively. Furthermore, the use of imaging techniques for overall indication criteria for ESD had a moderate utility value with an AUC of 0.71.

Conclusions

Our data suggested that, based on the combined use of GS, EUS, and MDCT, a high specificity of patient selection for ESD treatment can be achieved.

Predictive Factors for Lymph Node Metastasis and the Effect on Survival in Early Gastric Cancer Patients with Radical Gastric Resection

Objectives

Selected patients with early gastric cancer (GC) are treated endoscopically. Lymph node metastasis (LNM) in the T1 stage may also be detected during surgical resection for early GC. The aim of this study was to determine factors associated with LNM and the effect on survival.

Methods

A total of 63 patients with tumor invasion stage T1a or T1b who were operated on for early GC between 2010 and 2018 were included in the study. Parameters were investigated retrospectively to identify predictive factors for LNM and overall survival. Significance was defined with a 2-sided p-value of <0.05.

Results

Among the 63 patients, 21 (33.3%) had LNM. Lymphovascular invasion (LVI) (p=0.02) and a high-grade tumor (p=0.02) were significantly associated with LNM. The overall survival rate was 73.0%. The number of patients with LNM was greater among the deceased patients compared with the censored group (p=0.03). The median follow-up time of the entire group was 28 months (range: 12-55 months) while it was 23 months (range: 7-39 months) in the deceased group and 33.5 months (15.5-60 months) in the censored group (p=0.06). The mean survival was 62.36 months in patients with LNM and 71.99 months in those without LNM (p=0.09). The cut-off value determined for the neutrophil-to-lymphocyte ratio (NLR) was 2.33 and it was an effective value in survival analysis (p<0.05).

Conclusion

Surgical treatment should be considered for early GC patients with high-grade tumors and cases demonstrating LVI. The overall survival was shorter in patients with a high NLR value and LNM.

Endoscopic or Surgical Resection for Gastro-Esophageal Cancer

BACKGROUND

Early gastro-esophageal cancer is staged as m1 to m3 depending on the infiltration of the anatomical layers of the mucosa or, analogously, as sm1 to sm3 depending on the depth of infiltration into the submucosa. The risk of lymph node metastases is low in mucosal carcinoma but increases with the depth of infiltration into the submucosa.

METHODS

This review is based on pertinent publications retrieved by a selective search in MEDLINE, PubMed, the Cochrane Library, and the International Standard Randomised Controlled Trial Number (ISRCTN) registry.

RESULTS

New technologies such as narrow-band imaging have improved the endo- scopic diagnosis and staging of early gastro-esophageal cancer. The development of endoscopic submucosal dissection has led to a higher R0 resection rate, a lower risk of recurrence, and an increase in the number of endoscopic resections that are performed with curative intent. In squamous-cell carcinoma of the esophagus, surgical oncological esophagectomy is indicated if the cancer infiltrates into the third mucosal layer (T1a, m3) or deeper. In esophageal adenocarcinoma, the prevalence of lymph node metastases is low if the cancer is restricted to the mucosa and in- creases only when the submucosa is infiltrated. In the current German S3 guideline, endoscopic resection is recommended for intramucosal adenocarcinoma as long as there are no further histopathological risk factors. Lymph node metastasis in gastric carcinoma begins in the deep mucosal infiltration stage (m3). If certain special con- ditions ("extended criteria") are met, carcinoma expanding into the first submucosal layer (sm1) can be removed endoscopically. All further stages must be treated with total or subtotal gastrectomy with systematic D2 lymphadenectomy.

CONCLUSION

Borderline cases between endoscopic and surgical resection of early carcinoma of the esophagus or stomach must be managed with an interdisciplinary treatment algorithm. If there is a risk of lymph node metastasis, surgical oncological resection is indicated. Such resections of gastroesophageal cancer in the locally advanced stage should always be part of a multimodal treatment approach.

Risk Factors for Lymph Node Metastasis in Undifferentiated-Type Gastric Carcinoma

Undifferentiated-type carcinoma has a high incidence of lymph node metastasis. The independent risk factors for lymph node metastasis in undifferentiated-type carcinoma are invasion depth, tumor size, lymphovascular invasion, and presence of ulcer. In the cases that meet the curative resection criteria, no lymph node metastasis was observed in the Japanese studies, but some metastases were observed in Korean studies. After performing curative endoscopic submucosal dissection, the survival rate is similar to that of gastrectomy. The discrepancy between endoscopy and pathology is high in undifferentiated-type carcinoma. The tumor size in endoscopy is a significant risk factor for non-curative resection, and when the tumor size is small, the non-curative resection rate is significantly reduced. Lymphovascular invasion can be assessed in pathologic examination and D2-40 stain is helpful. The presence of ulcer should be determined by pathology, but ulcer's omission in pathology report makes the analysis difficult. Undifferentiatedtype carcinomas with differentiated-type components show higher lymph node metastasis rate than that of pure undifferentiatedtype carcinomas. The lymph node metastasis rate of signet ring cell type is lower than that of other undifferentiated-type carcinomas and is similar to differentiated-type carcinomas. The application of these additional histologic findings may improve the indication of endoscopic submucosal dissection.

AGA Institute Clinical Practice Update: Endoscopic Submucosal Dissection in the United States

Endoscopic submucosal dissection (ESD) is an established endoscopic resection method in Asian countries, which is increasingly practiced in Europe and by early adopters in the United States for removal of early cancers and large lesions from the luminal gastrointestinal tract. The intent of this expert review is to provide an update regarding the clinical practice of ESD with a particular focus on its use in the United States. This review is framed around the 16 best practice advice points agreed upon by the authors, which reflect landmark and recent published articles in this field. This expert review also reflects our experience as advanced endoscopists with extensive experience in performing and teaching others to perform ESD in the United States. Best Practice Advice 1: Endoscopic submucosal dissection should be recognized as a mature endoscopic technique that enables complete removal of lesions that are too large for en bloc endoscopic mucosal resection or are at increased risk of containing cancer. Best Practice Advice 2: The safety and feasibility of endoscopic submucosal dissection for early gastric cancer is well established. The absolute indications for curative endoscopic resection include moderately and well-differentiated, nonulcerated, mucosal lesions that are ≤2 cm in size. Best Practice Advice 3: Other relative (expanded) indications for gastric endoscopic submucosal dissection include moderately and well-differentiated superficial cancers that are >2 cm, lesions ≤3 cm with ulceration or that contain early submucosal invasion, and poorly differentiated superficial cancers ≤2 cm in size. The risk of lymph node metastasis when endoscopic submucosal dissection is performed for these indications is higher than when it is performed for absolute indications but remains acceptably low. Best Practice Advice 4: Endoscopic submucosal dissection may be considered in selected patients with Barrett's esophagus with the following features: large or bulky area of nodularity, lesions with a high likelihood of superficial submucosal invasion, recurrent dysplasia, endoscopic mucosal resection specimen showing invasive carcinoma with positive margins, equivocal preprocedural histology, and intramucosal carcinoma. Best Practice Advice 5: Endoscopic submucosal dissection is the primary modality for treatment of squamous cell dysplasia and cancer confined to the superficial esophageal mucosa. Any degree of submucosal invasion caries an increased risk of lymph node metastasis and alternative/additional therapy should be considered. Best Practice Advice 6: Duodenal endoscopic submucosal dissection is associated with an increased risk of intraprocedural perforation and delayed adverse events. Duodenal endoscopic submucosal dissection should be limited to endoscopists with extensive experience in performing endoscopic submucosal dissection in other locations. It is strongly suggested that endoscopists in the United States refrain from performing duodenal endoscopic submucosal dissection during the early phase of their endoscopic submucosal dissection practice. Best Practice Advice 7: All colorectal lesions should be evaluated for suitability for endoscopic resection. Accumulating evidence has shown that the majority of colorectal neoplasms without signs of deep submucosal invasion or advanced cancer can be treated by advanced endoscopic resection techniques. Best Practice Advice 8: Colorectal neoplasms containing dysplasia confined to the mucosa have no risk for lymph node metastasis and endoscopic resection should be considered as the criterion standard. Best Practice Advice 9: Large (>2 cm) colorectal lesions frequently (>43%) require piecemeal removal when endoscopic mucosal resection is used, which is associated with increased (up to 20%) rates of recurrent neoplasia. Endoscopic submucosal dissection enables higher rates of en bloc resection and lower recurrence rates for these lesions. Patients with large complex colorectal polyps should be referred to a high-volume, specialized center for endoscopic removal by endoscopic mucosal resection or endoscopic submucosal dissection. Best Practice Advice 10: Endoscopic resection for colorectal lesions offers significant cost benefit compared with surgery, and case-based endoscopic submucosal dissection selection for high-risk lesions could offer cost savings. Best Practice Advice 11: Endoscopists in the United States embarking on performing endoscopic submucosal dissection should be familiar with currently available endoscopic tissue closure devices. Both clip closure and endoscopic suturing techniques have been shown to be effective in managing intraprocedural perforation. Complete closure of a post-endoscopic submucosal dissection site may be considered in certain circumstances based on patient factors, procedural factors, and the location of the lesion. Best Practice Advice 12: Careful coagulation of exposed blood vessels in the resection site may reduce the risk of delayed bleeding after endoscopic submucosal dissection. The use of low-voltage coagulation current is recommended for this technique. Best Practice Advice 13: Endoscopists should affix the endoscopic submucosal dissection specimen to a flat surface (eg, pin the specimen to cork board) and immerse it in formalin. An expert gastrointestinal pathologist should evaluate the specimen for margin involvement, degree of differentiation, presence or absence of lymphovascular invasion, depth of submucosal invasion (if present), and tumor budding. Best Practice Advice 14: Acquiring high-level competency in endoscopic submucosal dissection is achievable in the United States. Alternative educational models should be used in the United States because of the limited number of experts and the differing prevalence of gastrointestinal luminal diseases as compared with Asia. Best Practice Advice 15: The endoscopic submucosal dissection educational model most suited for the current environment in the United States is a stepwise approach consisting of didactic self-study, attending training courses with increasing levels of complexity, self-practice on animal models, and observation of live cases performed by experts. Endoscopists should perform their initial endoscopic submucosal dissections on patients with lesions that have well-established indications for endoscopic submucosal dissection and are of the lowest technical complexity. Best Practice Advice 16: Endoscopists in the United States who perform endoluminal resection should educate referring physicians to avoid practices that may induce submucosal fibrosis hampering future endoscopic mucosal resection or endoscopic submucosal dissection. These practices include tattooing in close proximity to or beneath a lesion for marking and partial snare resection of a portion of a lesion for histopathology.

The incidence of lymph node metastasis in early gastric cancer according to the expanded criteria in comparison with the absolute criteria of the Japanese Gastric Cancer Association: a systematic review of the literature and meta-analysis

BACKGROUND AND AIMS

Japanese criteria for curative endoscopic resection of early gastric cancer initially included nonulcerated, well-differentiated mucosal lesions ≤2 cm in diameter, known as the absolute criteria. Subsequently, these indications were expanded to include larger, ulcerated, and undifferentiated mucosal lesions as well as differentiated lesions with slight submucosal invasion. Whether patients meeting the expanded criteria can be managed safely without gastrectomy and lymph node dissection has been controversial. The risk of lymph node metastasis (LNM) in patients who met the expanded criteria is a critical factor in determining the best course of management for these patients.

METHODS

We comprehensively searched main reference databases for studies that included patients who underwent gastrectomy and lymph node dissection for early gastric cancer. A meta-analysis was conducted by using the random effects model. Relative risk reduction was used to compare the incidence of LNM in patients meeting the absolute criteria as compared with those meeting the expanded criteria.

RESULTS

Twelve studies met the inclusion criteria, providing a total of 9798 patients. The incidence of LNM was 0.2% for patients who met the absolute criteria as compared with 0.7% for patients who met the expanded criteria. Analysis of the various components of the expanded criteria was conducted, revealing that the incidence of LNM for differentiated mucosal lesions ≤3 cm with ulceration and for differentiated mucosal lesions without ulceration, irrespective of size, was 16 of 2814 (0.57%), reference range (RR) 3.01; P = .02 and 8 of 3004 (0.27%), RR 1.69; P = .37, respectively, only marginally higher than the risk of LNM associated with the absolute criteria. In contrast, undifferentiated mucosal lesions ≤2 cm and differentiated lesions <3 cm with slight submucosal invasion had a significantly higher incidence of LNM in comparison with the absolute criteria (25/972 [2.6%], RR 6.79; P = .0004 and 8/315 [2.5%], RR 6.30; P = .004, respectively).

CONCLUSION

Overall, expanding the indication for endoscopic resection to include mucosal nonulcerated differentiated lesions irrespective of size and differentiated mucosal ulcerated lesions <3 cm is justified with minimal increased risk in comparison to the absolute criteria. However, expanding the indication for undifferentiated lesions ≤2 cm and differentiated lesions with slight submucosal invasion (T1b) should be balanced with the risks of surgery, given the increased risk of LNM in these patients.

Survival Benefit of Additional Surgery After Non-curative Endoscopic Submucosal Dissection for Early Gastric Cancer: A Propensity Score Matching Analysis

BACKGROUND AND PURPOSE

Previous studies comparing survival outcomes between patients who did and did not undergo additional surgery after non-curative endoscopic submucosal dissection (ESD) for early gastric cancer (EGC) were limited in that the baseline characteristics differed significantly between the groups. We aimed to address this limitation and compared survival outcomes between these two groups using propensity score matching analysis.

METHODS

The study enrolled 1969 consecutive patients who underwent non-curative ESD for EGC between 2000 and 2011 at any of 19 institutions across Japan. Using propensity score matching analysis, patients who underwent additional surgery (n = 1064) were compared with patients who did not (n = 905). Overall survival (OS) and disease-specific survival (DSS) after ESD were compared between both groups.

RESULTS

Propensity score matching analysis yielded 553 matched pairs and well-balanced baseline characteristics between the two groups. The 5-year OS rates were 91.0% in the additional surgery group and 75.5% in the no additional surgery group, and the 5-year DSS rates were 99.0 and 96.8%, respectively. OS and DSS in the additional surgery group were significantly higher than in the no additional surgery group (OS, p < 0.001; DSS, p = 0.013). In Cox proportional hazard analysis, additional surgery significantly reduced gastric cancer-related death after non-curative ESD for EGC (hazard ratio 0.33, 95% confidence interval 0.12-0.79, p = 0.012).

CONCLUSIONS

Our findings suggest that additional surgery reduces mortality after non-curative ESD for EGC. We recommend additional surgery for patients after non-curative ESD for EGC.

Does the interval of screening endoscopy affect survival in gastric cancer patients?: A cross-sectional study

Gastric cancer remains the second most common cancer in Korea; however, its mortality has decreased due to earlier diagnosis. In Korea, screening endoscopy has been performed nationwide since 1999. The aim of this study was to elucidate the benefit of screening endoscopy on actual survival in gastric cancer patients and to determine the optimal interval of screening endoscopy.We analyzed 1651 patients diagnosed with gastric adenocarcinoma who underwent surgical treatment between June 2008 and December 2014. Patients were divided into 4 groups according to the interval of screening endoscopy prior to their gastric cancer diagnosis. (Group I = within 1 year, Group II = >1 but <2 years, Group III = more than 2 years, Group IV = no prior endoscopic examination). Patient demographics, clinicopathologic characteristics, and postoperative surgical outcomes including overall survival were compared.The 5-year gastric cancer-specific survival rates of groups I and II were significantly higher than groups III and IV (90.9% vs 85.4%, P = 0.002, respectively). Multivariate analysis showed that screening interval was an independent factor for the diagnosis of advanced gastric cancer. The risk of advanced gastric cancer decreased in group I (odds ratio: 0.515, 95% confidence interval [CI] 0.369-0.719; P < 0.001) and group II (odds ratio: 0.678, 95% CI 0.517-0.889, P = 0.005).Screening endoscopy was helpful in increasing the survival of gastric cancer patients. A 2-year endoscopic screening interval is suitable to detect early-stage gastric cancer.

A case of undifferentiated-type mucosal gastric cancer with multiple lymph node metastases fulfilling the curative criteria for endoscopic resection according to routine pathological analysis

BACKGROUND

Endoscopic resection is accepted as the standard treatment for early mucosal gastric cancer, and its indications have recently been expanded while its long-term outcomes are still unclear. Herein, we present a didactic case of undifferentiated-type mucosal gastric cancer fulfilling the expanded indication and curative criteria for endoscopic submucosal dissection (ESD), having synchronous multiple lymph node metastases.

CASE PRESENTATION

A 40-year-old woman was found to have a Helicobacter pylori infection at a standard health check with no abdominal symptoms. She received an upper gastrointestinal endoscopy and found to have an undifferentiated-type mucosal gastric cancer with the size of 15 mm in diameter without ulceration, which fulfilled the expanded indication for ESD. According to patient's preference, we performed laparoscopy-assisted distal gastrectomy with D1+ lymph node dissection, and routine pathological analysis revealed a predominantly signet ring cell carcinoma limited to the mucosa without ulceration or any vessel involvement; on the other hand, 15 lymph node metastases were detected. Then, we added deep sectioning of the whole tumoral area at a thickness of 20 μm and immunohistochemical analyses. As the result, an isolated lymphatic capillary involvement of the extremely superficial submucosa was identified in a single histological section, and pathological diagnosis was corrected to ly1. She received postoperative adjuvant chemotherapy with an S-1 oral agent and had no recurrence under strict surveillance for 1 year postoperatively.

CONCLUSIONS

When we perform ESD for undifferentiated-type gastric cancer, deep sectioning of the whole tumoral area into thin slices and immunohistochemical staining using D2-40 should be practically considered.

Race Is a Risk for Lymph Node Metastasis in Patients With Gastric Cancer

BACKGROUND

The frequency of lymph node metastasis in each T stage of gastric cancer has not been as well described for Western populations as it has for Asian populations. This study aimed to determine these frequencies and to investigate risk factors associated with lymph node metastases in a racially diverse U.S.

POPULATION

METHODS

A prospectively maintained database of 8260 patients with gastric or gastroesophageal junction adenocarcinoma treated at our institution from 1995 to 2013 was reviewed to identify those who underwent surgical resection without preoperative therapy. Associations between clinicopathologic variables and lymph node metastasis were tested with uni- and multivariate analyses.

RESULTS

The study identified 218 patients with a pathologic diagnosis of gastric adenocarcinoma who underwent upfront gastrectomy. These study subjects included 115 white (53 %), 19 black (9 %), and 41 Asian (19 %) patients. At least 15 lymph nodes were examined in 148 (68 %) of the patients. The lymph node metastasis rates were 10 % for stage T1a, 34 % for stage T1b, 44 % for stage T2, 73 % for stage T3, and 95 % for stage T4 tumors. Univariate analysis showed that submucosal invasion, race, 15 or more lymph nodes examined, and lymphovascular invasion were associated with lymph node metastasis in T1 and T2 tumors. The multivariate analysis showed all but lymphovascular invasion to be independent risk factors for nodal metastasis.

CONCLUSIONS

The rates of lymph node metastasis observed in this study were higher than those reported in Asian reports. Race was an independent risk factor for lymph node metastasis. Caution is therefore needed when evidence from Asian countries is extrapolated to more racially diverse Western countries.

Survival rates in T1 and T2 gastric cancer: A Western report

BACKGROUND AND OBJECTIVES

The purpose of this study was to identify clinicopathologic factors associated with overall survival (OS) in early T stage gastric cancer in a Western population.

METHODS

Patients with stage T1 or T2 gastric or gastroesophageal adenocarcinoma who had undergone upfront gastrectomy from 1995 to 2013 were identified in an institutional database.

RESULTS

We identified 121 patients with pathologic stage T1 or T2 tumors (49 [41%] T1a; 49 [41%] T1b; and 23 [19%] T2) who underwent R0 resection without preoperative treatment. Of these, 53% were white, 9% African American, 17% Hispanic, and 22% Asian. The median follow-up was 5.7 years, and the 5-year OS rate was 89% (98%, 93%, and 66% for patients with T1a, T1b, and T2 tumors, respectively). Univariate analysis revealed a higher risk of death in patients with T2 tumors and those of African American race. On multivariate analysis, T2 stage was the only variable independently associated with OS (hazard ratio, 2.80; 95% confidence interval, 1.11-7.12; P = 0.03).

CONCLUSION

In this study of a Western population of patients with T1 or T2 gastric cancer, T2 stage was associated with diminished OS, whereas nodal status and race were not. J. Surg. Oncol. 2016;114:602-606. © 2016 Wiley Periodicals, Inc.