Clinical validity of endoscopic submucosal dissection for submucosal invasive gastric cancer: a single-center study

Background

The 2010 Japanese Gastric Cancer Association guidelines for the treatment of submucosal invasive gastric cancer (SM-GC) specify size 30?mm or less, differentiated-dominant histology, lack of vessel involvement, and submucosal invasion of less than 500???m (SM1) as expanded criteria for curative endoscopic resection. Our purpose in this study was to confirm the validity of the expanded indications for curative endoscopic submucosal dissection (ESD) of SM-GC.

Methods

The study subjects were 173 patients with SM-GC resected by ESD at Hiroshima University Hospital between April 2002 and September 2010, including 99 patients for whom 3-plus years?? follow-up information was available. Post-ESD outcomes were compared between cases of SM1-GC that met the expanded ESD criteria, those that did not, and SM2-GC cases.

Results

Complete resection was achieved for 93.2% of the SM1-GCs that met the expanded criteria. There was neither metastasis to lymph nodes or other organs nor local recurrence among the SM1-GCs. Disease-specific survival did not differ significantly between patients that were simply followed up after ESD and those that were treated by additional surgical resection.

Conclusions

Our outcome data support the clinical validity of ESD without additional surgical resection for SM1-GCs that meet the expanded criteria.     

Indications for EMR/ESD in cases of early gastric cancer: relationship between histological type,depth of wall invasion,and lymph node metastasis

Background Limited surgery by endoscopic mucosal resection (EMR) or endoscopic submucosal dissection (ESD) for gastric cancer is frequently performed in many institutions. These techniques do preserve gastric function and maintain a high quality of life but may compromise survival. The treatment strategy for early tumors should therefore be based on a complete cure, and limited surgery must thus have clear indications. Methods D2 gastric resection was performed in 278 early gastric adenocarcinomas, and a retrospective histological review of the specimens was made. The extended indications for EMR or ESD, according to the Japanese Gastric Cancer Association Treatment guidelines for gastric cancer in Japan, were also assessed. Results Of the 278 early gastric cancers, 115 were mucosal (M) cancers without ulcer. No lymph node metastases were seen in these specimens. Six of the 41 specimens of M cancer with ulcers had lymph node metastases at the N1 level only. One of these had lymph node metastases from a tumor measuring less than 3 cm in size. Twenty-eight of 122 submucosal cancers had lymph node metastases (23%). Twenty of these were SM1 tumors and 5 had lymph node metastases; 4 of these 5 had lymph node metastases despite the absence of vascular invasion. Conclusion Three cases had lymph node metastases that met the extended criteria for EMR/ESD. EMR and/or ESD should be limited to M cancers without ulcer or differentiated-type M cancer with ulcers smaller than 2 cm. When the depth of tumor invasion is deeper than M, then a gastric resection with lymph node dissection is necessary.     

Risk of Lymph Node Metastases from Early Gastric Cancer in Relation to Depth of Invasion: Experience in a Single Institution

Background: An accurate assessment of potential lymph node metastasis is important for the appropriate treatment of early gastric cancers. Therefore, this study analyzed predictive factors associated with lymph node metastasis and identified differences between mucosal and submucosal gastric cancers. Materials and Methods: A total of 518 early gastric cancer patients who underwent radical gastrectomy were reviewed in this study. Clinicopathological features were analyzed to identify predictive factors for lymph node metastasis. Results: The rate of lymph node metastasis in early gastric cancer was 15.3% overall, 3.3% for mucosal cancer, and 23.5% for submucosal cancer. Using univariate analysis, risk factors for lymph node metastasis were identified as tumor location, tumor size, depth of tumor invasion, histological type and lymphovascular invasion. Multivariate analysis revealed that tumor size >2 cm, submucosal invasion, undifferentiated tumors and lymphovascular invasion were independent risk factors for lymph node metastasis. When the carcinomas were confined to the mucosal layer, tumor size showed a significant correlation with lymph node metastasis. On the other hand, histological type and lymphovascular invasion were associated with lymph node metastasis in submucosal carcinomas. Conclusions: Tumor size >2 cm, submucosal tumor, undifferentiated tumor and lymphovascular invasion are predictive factors for lymph node metastasis in early gastric cancer. Risk factors are quite different depending on depth of tumor invasion. Endoscopic treatment might be possible in highly selective cases.     

A case of small undifferentiated intramucosal gastric cancer with lymph node metastasis

Early gastric cancer (EGC) has a favorable prognosis after surgical gastrectomy. For intramucosal EGC with little risk of lymph node metastasis, endoscopic mucosal resection (EMR) is an accepted treatment method. Herein we document a noteworthy case of small undifferentiated gastric cancer with nodal metastasis. A 60-year-old Japanese woman underwent gastrectomy with D2 lymph node dissection for the treatment of EGC in the lower gastric body. Histological examination revealed that signet-ring cell carcinoma was located in approximately one-third of the superficial portion of the mucosal layer, with a tumor size of 13 mm. No lymphatic invasion, venous invasion, or fibrosis was observed in the submucosal layer. This case had nodal metastasis and was finally diagnosed as stage IB (T1N1M0) according to the Japanese Classification of Gastric Carcinoma (JCGC). The patient is alive without recurrence 6 years after treatment.     

Depth-predicting score for differentiated early gastric cancer

Background  

Intramucosal and minute submucosal (M-SM1; <500 μm in depth) differentiated gastric cancers, which have a negligible risk of lymph node metastasis, are the targets for endoscopic resection. However, there have been few reports about the endoscopic distinction between these cancers and cancers with deeper submucosal invasion (SM2; ≥500 μm in depth). The aim of this retrospective study was to analyze the differences in the endoscopic features between M-SM1 and SM2 cancers, and to develop a simple scoring model to predict the depth of these early gastric cancers.     

Lymphovascular invasion is an important predictor of lymph node metastasis in endoscopically resected early gastric cancers

With an increased incidence of early gastric cancer (EGC) and advances in endoscopic technologies, endoscopic resection (ER) has become an important treatment modality for EGC. Therefore, precise assessment of the risk of lymph node (LN) metastasis in ER specimens has become essential. The widely accepted criteria for ER have been mostly obtained from surgical data. This study was performed to evaluate the adequacy of these criteria and re-evaluate the predictive power of the criteria for LN metastasis. We evaluated a series of pathologic factors in ER specimens from 79 gastric cancer patients treated with endoscopic mucosal resection (7) or endoscopic submucosal dissection (72) and underwent subsequent surgical resection due to the potential risk of LN metastasis. Of the 79 patients, 10 patients (12.7%) exhibited regional LN metastasis. Univariate analysis revealed that the presence of lymphovascular invasion (LVI) was significantly associated with LN metastasis (26/69, 37.7 vs. 9/10, 90%, P = 0.004). The number of LVI was significantly higher in the LN metastasis group (1.1 ± 2.3 vs. 7.7 ± 8.4, P<0.001). By multivariate analysis, the presence of LVI (odds ratio, 21.41; P = 0.010) and undifferentiated histology (odds ratio, 11.15; P = 0.016) were significantly correlated with LN metastasis. The presence of LVI, undifferentiated histology and the numbers of LVI were important risk factors for LN metastasis. Among these factors, the presence of LVI was the most important risk factor for LN metastasis in endoscopically resected early gastric cancer.     

A case of single lymph node metastasis near the common hepatic artery following a curative endoscopic resection for gastric mucosal cancer

Although the absolute indication for endoscopic resection (ER) in gastric cancer is widely accepted, expanded indication for endoscopic submucosal dissection (ESD) is still regarded as investigational because of the risk of concomitant lymph node (LN) metastasis or recurrence following ESD. However, LN metastasis in early gastric cancer confined to absolute indication for ER cannot be negligible. Herein we report a 72-year-old man who underwent laparoscopic distal gastrectomy for LN metastasis around the common hepatic artery following curative ESD to the lesion that had met as an absolute indication for ER 1 year ago. There was only one metastatic LN near the common hepatic artery (LN 8), without malignancy at the ESD site or other harvested LNs.     

Risk factors for lymph node metastasis in early gastric cancer without lymphatic invasion after endoscopic submucosal dissection

BackgroundLymphatic invasion (LI) is a potent risk factor for lymph node metastasis (LNM) in early gastric cancer (EGC) after endoscopic submucosal dissection (ESD). However, there are also other risk factors for LNM. Hence, to identify the need for additional surgery in some case of EGC without LI, the present study aimed to identify the risk factors for LNM in patients with EGC without LI.MethodsData from 2284 patients diagnosed with EGC who underwent curative surgery at National Cancer Center in Korea from January 2012 to May 2019 were collected. The clinicopathological characteristics of patients with EGC without LI were compared on the basis of LNM status.ResultsThere were 339 (17.1%) and 1648 (82.9%) patients with and without LI respectively. Among these patients with and without LI, 118 (34.8%) and 91 (5.5%) patients presented with LNM, respectively. In patients with EGC without LI, tumor size larger than 3 cm (OR = 2.12, 95% CI = 1.22–3.68; p = 0.007), submucosal invasion (OR = 4.14, 95% CI = 2.57–6.65; p < 0.001), and undifferentiated histologic type (OR = 2.33, 95% CI = 1.45–3.76; p < 0.001) were significant risk factors for LNM. Rates of LNM in patients meeting absolute, expanded, and beyond expanded criteria without LI were 0%, 1.5% (OR = 3.27, 95% CI = 0.18–59.41; p = 0.423), and 7.3% respectively. When the expanded criteria were divided into four subtypes patients with EGC, without LI within each subtype did not show significant risk of incidence of LNM compared to the absolute criteria.ConclusionsThe current expanded criteria for endoscopic resection (ER) are tolerable in cases without LI, even though minimal risk LNM exists. Therefore, additional surgery may not be needed for patients meeting expanded criteria for ER.     

胃上部与胃中下部早期癌的临床病理特征#br# 比较研究#br#

目的对比分析胃上部早期癌（UGC）与胃中下部早期癌（M LGC）的临床及病理特征。方法回顾性分析2016年1月至2020年5月于南京医科大学第一附属医院消化内科接受内镜黏膜下剥离术（ESD）且术后病理证实为早期胃癌（EGC）的379例患者的临床病理资料,根据患者病灶部位分为UGC组（180例）与M LGC组（199例）,比较两组患者的基本资料、病灶内镜下特征及随访情况等。采用Logistic回归分析EGC黏膜下浸润及淋巴结转移的危险因素。结果UGC组年龄≥60岁、男性比例高于M LGC组,慢性萎缩性胃炎、肠上皮化生比例低于M LGC组,差异有统计学意义（P<005）。两组巴黎分型、组织学类型、黏膜下浸润、淋巴结转移差异有统计学意义（P<005）,肿瘤直径和治愈性切除差异无统计学意义（P>005）。UGC组、M LGC组发生黏膜下浸润者分别有66例、34例。Logistic回归分析显示,胃上部位置、淋巴结转移、未分化型是EGC黏膜下浸润的独立危险因素。肿瘤黏膜下浸润、未分化型是EGC淋巴结转移的独立危险因素。两组短期疗效（整块切除、完全切除、愈性切除、出血、穿孔）和长期疗效（复发、死亡）差异均无统计学意义（P>005）。结论在评估UGC达到ESD适应证的前提下,可优先选择内镜下切除。     

Nomogram for predicting lymph node metastasis rate of submucosal gastric cancer by analyzing clinicopathological characteristics associated with lymph node metastasis

Background

To combine clinicopathological characteristics associated with lymph node metastasis for submucosal gastric cancer into a nomogram.

Methods

We retrospectively analyzed 262 patients with submucosal gastric cancer who underwent D2 gastrectomy between 1996 and 2012. The relationship between lymph node metastasis and clinicopathological features was statistically analyzed. With multivariate logistic regression analysis, we made a nomogram to predict the possibility of lymph node metastasis. Receiver operating characteristic (ROC) analysis was also performed to assess the predictive value of the model. Discrimination and calibration were performed using internal validation.

Results

A total number of 48 (18.3%) patients with submucosal gastric cancer have pathologically lymph node metastasis. For submucosal gastric carcinoma, lymph node metastasis was associated with age, tumor location, macroscopic type, size, differentiation, histology, the existence of ulcer and lymphovascular invasion in univariate analysis (all P<0.05). The multivariate logistic regression analysis identified that age ≤50 years old, macroscopic type III or mixed, undifferentiated type, and presence of lymphovascular invasion were independent risk factors of lymph node metastasis in submucosal gastric cancer (all P<0.05). We constructed a predicting nomogram with all these factors for lymph node metastasis in submucosal gastric cancer with good discrimination [area under the curve (AUC) =0.844]. Internal validation demonstrated a good discrimination power that the actual probability corresponds closely with the predicted probability.

Conclusions

We developed a nomogram to predict the rate of lymph node metastasis for submucosal gastric cancer. With good discrimination and internal validation, the nomogram improved individualized predictions for assisting clinicians to make appropriated treatment decision for submucosal gastric cancer patients.     

Successful application of laparoscopic and endoscopic cooperative surgery (LECS) for a lateral-spreading mucosal gastric cancer

In the current era of endoscopic submucosal dissection (ESD) for early gastric cancer, which carries a negligible risk of lymph node metastasis, local resection of the stomach remains an option for these lesions. This is particularly so for a large intramucosal lesion or a lesion with a strong ulcer scar, for which ESD becomes a difficult option. Here, we describe a case of lateral-spreading intramucosal gastric cancer of 6-cm diameter located at the fornix of the stomach, which was successfully treated by laparoscopic and endoscopic cooperative surgery (LECS) because of the expected risk of complications during ESD. In the LECS procedure, the resection margin was appropriately determined by the endoscopic evaluation in detail and by the ESD technique. If early gastric cancer fits the criteria for endoscopic resection but would present difficulty if performing ESD, this is a good indication for the LECS procedure.     

Two rare cases of node-positive differentiated gastric cancer despite their infiltration to sm1, their small size, and lack of lymphatic invasion into the submucosal layer

Early gastric cancer without lymph node metastasis has been reported after the analysis of many cases, and a consensus has been reached about this condition. We report two cases of node-positive differentiated sm1 gastric cancer without lymphatic invasion into the submucosal layer. Case 1 was a 73-year-old man who underwent EMR for 0-IIc early gastric cancer (EGC) on the gastric angle, with a histological diagnosis of tub1. Pathological examination revealed a 0-IIc lesion that was 12 mm in size and sm1 in invasion depth without lymphatic-vascular invasion. However, the infiltration in the submucosal layer was relatively wide. The patient subsequently underwent distal gastrectomy with D2 lymph node dissection. Pathological examination revealed level 2 lymph node metastasis. Case 2 was a 62-year-old woman who underwent ER for a 0-I+IIc-type EGC on the greater curvature of the antrum, with a histological diagnosis of tub1. Pathological examination revealed a 0-I+IIc-type lesion that was 15 mm in size and sm1 in depth. Lymphatic invasions in the muscularis mucosa were found, but none were seen in the submucosal layer. Two years later, follow-up computed tomography (CT) showed a lymph node swelling in the infrapyloric region. Distal gastrectomy with D2 dissection was then performed, and pathological examination revealed level 1 lymph node metastasis. Although the lesions in both patients satisfied the criteria of Gotoda et al. for minimal risk of nodal involvement, lymph node metastasis was observed in these patients. Curative surgery with lymph node dissection is thus required in patients with wide infiltration of the submucosal layer or lymphatic invasion in the muscularis mucosa.     

Rate of detection of lymph node metastasis is correlated with the depth of submucosal invasion in early stage gastric carcinoma.

BACKGROUND: Gastric carcinoma invading the submucosa is often accompanied by lymph node metastasis. However, the relation between the depth of submucosal invasion and the status of metastasis has not been investigated. The objective of this study was to clarify the relation between lymph node status and the histologic features of gastric carcinoma invading the submucosa. METHODS: The histopathology of 118 patients who underwent gastrectomy and lymph node dissection for gastric carcinoma invading the submucosa was examined. These pT1 tumors with invasion of the submucosa were confirmed by histologic examination of the resected specimens. Tumor size, depth of submucosal invasion, histologic type, and macroscopic type were investigated in association with presence or absence of and anatomic level of lymph node metastasis. RESULTS: Among the 118 patients, 16 (14%) had lymph node metastasis, and the status of metastasis significantly correlated with tumor size and depth of submucosal invasion. The frequency of metastasis to perigastric lymph nodes and extragastric lymph nodes was 0% and 0% for < or =1-cm tumors, 5% and 1% for 1- to 4-cm tumors, and 46% and 15% for >4-cm tumors, respectively. There was no lymph from a node metastasis in tumors with less than 300 microm of submucosal invasion. The frequency of lymph node metastasis for tumors with 300-1000 microm and >1000 microm of submucosal invasion were 19% and 14%, respectively. CONCLUSIONS: Tumor size and depth of submucosal invasion serve as simple and useful indicators of lymph node metastasis in early stage gastric carcinoma. Optimal lymph node dissection levels are as follows: 1) local resection (D0) for lesions < or =1 cm, 2) limited lymph node dissection (D1) for 1- to 4-cm lesions, and 3) radical lymph node dissection (D2) for lesions >4 cm. When submucosal invasion of a locally resected tumor is more than 300 microm, additional gastrectomy and lymph node dissection are necessary.     

Clinicopathologic features and prognosis analysis of mucinous gastric carcinoma

Mucious gastric carcinoma (MGC) is a subtype of gastric carcinoma and its clinicopathologic features and prognosis still remain unclear. To investigate the clinical significance and surgical outcomes of mucinous gastric carcinoma, 2,769 patients with gastric carcinoma were analyzed in a case control study. We reviewed the records of 196 patients with mucinous gastric carcinoma and 2,573 with nonmucinous gastric carcinoma (NGC). Clinicopathologic features and survival rate of patients were analyzed. In all registered patients, patients with MGC had a larger size, more T3 and T4 invasion to the gastric wall, more positive lymph node metastasis, more III and IV stage and more positive peritoneal dissemination, but less curative gastrectomy. In curative gastrectomy patients, MGC had larger size, deeper invasion to gastric wall, more positive lymph node metastasis and more advanced TNM stage. The overall survival rate in curative gastrectomy patients with MGC was significantly lower than that for patients with NGC (P < 0.021). Age (P = 0.001), location of tumor (P < 0.001), Borrmann type (P = 0.037), depth of invasion (P < 0.001), lymph node metastasis (P < 0.001) and lymphovascular invasion (P = 0.001) were independent prognostic factors of gastric carcinoma, but MGC itself was not. The prognosis of MGC did not have significant difference compared with NGC. Frequently, MGC was of advanced stage at the time of diagnosis. Age, location of tumor, Borrmann type, depth of invasion, lymph node metastasis and lymphovascular invasion are independent prognostic factors of gastric carcinoma, but mucinous histological type itself is not. Further study on the origin and progression of MGC is needed in future.     

Clinical outcomes of early gastric cancer patients after noncurative endoscopic submucosal dissection in a large consecutive patient series

Background

Clinical outcomes of early gastric cancer (EGC) patients after noncurative endoscopic submucosal dissection (ESD) have not been fully elucidated; we therefore aimed to clarify these outcomes.

Methods

A total of 3058 consecutive patients with 3474 clinically diagnosed EGCs at initial onset underwent ESD with curative intent at our hospital between 1999 and 2010. We retrospectively assessed the following clinical outcomes of noncurative gastric ESD patients with a possible risk of lymph node (LN) metastasis by dividing patients into two groups with different treatment strategies (additional gastrectomy and simple follow-up): presence of LN metastasis at the time of gastrectomy, incidence of LN and distant metastases during the follow-up period, clinicopathological factors associated with metastasis, and 5-year disease-specific survival (DSS).

Results

After exclusion of 75 noncurative ESD patients with only a positive horizontal margin, 569 noncurative ESD patients with a possible risk of LN metastasis were identified. Among the 356 patients undergoing additional gastrectomy, LN metastasis was identified in 18 patients. A positive vertical margin with submucosal invasion (odds ratio 3.6) and lymphovascular invasion (odds ratio 3.5) were significantly associated with LN metastasis. The 5-year DSS rate was 98.8 %. Among the 212 patients who underwent simple follow-up, LN and/or distant metastases were found in eight patients. In this group, lymphovascular invasion (hazard ratio 6.6) was significantly associated with metastasis with a 5-year DSS rate of 96.8 %.

Conclusions

Additional gastrectomy should be performed particularly in noncurative gastric ESD patients with lymphovascular invasion or a positive vertical margin with submucosal invasion.

     

Prognostic role of lymph node metastasis in early gastric cancer

Objective： To clarify the relationship between clinicopathological features and lymph node metastasis and to propose the potential indications of lymph node metastasis for prognosis in early gaswic cancer （EGC） patients. Methods： We retrospectively observed 226 EGC patients with lymph node resection, and analyzed the associations between lymph node metastasis and clinicopathological parameters using the chi-square test in univariate analysis and logistic regression analysis in multivariate analysis. Overall survival analysis was determined using the Kaplan-Meier and log-rank test. We conducted multivariate prognosis analysis using the Cox proportional hazards model. Results： Of all the EGC patients, 7.5% （17/226） were histologically shown to have lymph node metastasis. The differentiation, lymphovascular invasion and depth of invasion were independent risk factors for lymph node metastasis in EGC. The 5- and 10-year survival rates were significantly lower in patients with lymph node metastasis than in those without and the patients also had shorter progress-free survival time. Lymph node metastasis and tumor size were independent prognostic factors for EGC. The status of the lymph nodes was a significant factor in predicting recurrence or metastasis after surgery. Conclusions： The undifferentiated carcinoma and lymphovascular and/or submucosal invasion were associated with a higher incidence of lymph node metastasis in EGC patients, whom need to perform subsequent D2 lymphadenectomy or laparoscopic lymph node dissection and more rigorous follow-up or additional chemotherapy/radiation after D2 gastrectomy for poor prognosis and high recurrence/metastasis rate.     

An oral anticancer drug, TS-1, enabled a patient with advanced gastric cancer with Virchow's metastasis to receive curative resection

We encountered a patient with advanced gastric cancer, with Virchow's lymph node metastasis, who subsequently underwent curative resection after neoadjuvant chemotherapy with the newly developed oral anticancer drug, TS-1. The patient was a 67-year-old woman who had a type 2 tumor in the middle third of the stomach, and Virchow's lymph node metastasis, which was diagnosed by fine-needle aspiration cytology; she also had swollen paraaortic lymph nodes. Curative resection was considered impossible, and TS-1 (100 mg/day) was administered for 28 days in one course, mainly in the outpatient clinic. Although grade 2 stomatitis interrupted the therapy on day 21 of the second course and on day 7 of the third course, the type 2 tumor showed marked remission (partial response; PR) and the metastasis in the Virchow's and paraaortic lymph nodes had completely disappeared after the third course (complete response; CR). Eleven weeks after the completion of the TS-1 treatment, total gastric resection with D3 lymph node dissection was performed. Histopathological examination revealed tumor involvement only in the mucosal and submucosal layers of the stomach and the no. 4d lymph node. Most of the tumor was replaced with fibrosis with granulomatous change in the muscularis propria of the stomach and in the no. 3, no. 6, and no. 7 lymph nodes. This may be the first report of a patient with advanced gastric cancer with Virchow's lymph node metastasis who successfully received curative resection following neoadjuvant chemotherapy with a single oral anticancer drug. Received: August 7, 2001 / Accepted: January 28, 2002     

直肠神经内分泌肿瘤淋巴结转移的危险因素分析及内镜切除方式比较

背景与目的： 直肠神经内分泌肿瘤（rectal neuroendocrine neoplasm,R-NEN）的发病率呈上升趋势,但其治疗仍存在争议,特别是10 ~ 20 mm之间的肿瘤。本研究通过分析R-NEN的临床病理学特征,探讨其淋巴结转移的危险因素,并比较不同内镜切除效果的差异,探索内镜治疗R-NEN的适应证及方式。方法： 回顾性分析2007年2月—2020年12月河北医科大学第四医院收治的R-NEN患者的相关临床信息,分析淋巴结转移的危险因素,比较不同内镜切除方式的安全性和有效性。结果： 共分析了190例R-NEN患者的临床病理学特征,结果显示,肿瘤大小≥12.5 mm（OR = 69.081,95% CI：11.385 ~ 419.155,P<0.001）和淋巴管血管侵犯（OR = 11.732,95% CI：1.028 ~ 84.567,P = 0.015）是淋巴结转移的独立危险因素。比较内镜下套帽辅助黏膜切除术（endoscopic mucosal resection with cap,EMR-c）和内镜下黏膜下剥离术（endoscopic submucosal dissection,ESD）治疗114例R-NEN患者的临床资料,结果显示,EMR-c组的手术时间明显短于ESD组[（10.23±1.99）min vs （24.78±8.09）min,P<0.001]。两组的内镜整块切除率、病理学完全切除率和并发症发生率差异无统计学意义（P>0.05）。结论： 肿瘤大小≥12.5 mm和淋巴管血管侵犯是R-NEN患者淋巴结转移的独立危险因素。对于<12.5 mm且无淋巴结转移的R-NEN来说,EMR-c和ESD均是安全有效的治疗方法。     

Endoscopic Treatment of Superficial Gastric Cancer: Present Status and Future

Although the mortality rates of gastric cancer (GC) are gradually declining, gastric cancer is still the fourth leading cause of cancer-related death worldwide. This may be due to the high rate of patients who are diagnosed with GC at advanced stages. However, in countries such as Japan with endoscopic screening systems, more than half of GCs are discovered at an early stage, enabling endoscopic resection (ER). Especially after the introduction of endoscopic submucosal dissection (ESD) in Japan around 2000, a high en bloc resection rate allowing pathological assessment of margin and depth has become possible. While ER is a diagnostic method of treatment and may not always be curative, it is widely accepted as standard treatment because it is less invasive than surgery and can provide an accurate diagnosis for deciding whether additional surgery is necessary. The curability of ER is currently assessed by the completeness of primary tumor removal and the possibility of lymph node metastasis. This review introduces methods, indications, and curability criteria for ER of EGC. Despite recent advances, several problems remain unsolved. This review will also outline the latest evidence concerning future issues.     

Pathological factors related to lymph node metastasis of submucosally invasive gastric cancer: criteria for additional gastrectomy after endoscopic resection

Background

There are currently no universally accepted indications and criteria for additional gastrectomy after endoscopic resection of submucosally invasive cancer. The purpose of the present study was to establish accurate indications and criteria for such additional gastrectomy on the basis of lymph node metastasis risk.

Methods

We investigated 130 submucosally invasive gastric cancers and analyzed the pathological risk factors for lymph node metastasis. The tumors were evaluated for pathological factors in the area of invasion, and factors were compared between the cases with lymph node metastasis and those without.

Results

Univariate logistic regression analysis showed that tumor minor axis length, depth of invasion, histological classification of the area of submucosal invasion, absence of lymphoid infiltration, ulceration or scar in the lesion, and lymphatic and venous invasion are statistically significant risk factors for lymph node metastasis. Multivariate logistic regression analysis showed that the absence of lymphoid infiltration and the presence of lymphatic invasion are statistically significant as risk factors for lymph node metastasis.

Conclusions

We present a scoring system on the basis of the pathological criteria tested in this study. Our findings enable more accurate identification of patients who should undergo additional gastrectomy after endoscopic resection.