Risk of recurrent gastric cancer after endoscopic resection with a positive lateral margin

Predictors of residual neoplasia after noncurative (R1) endoscopic submucosal dissection of lesions in the gastrointestinal tract

BACKGROUND

Endoscopic submucosal dissection (ESD) is a minimally invasive resection technique that enables the en bloc resection of gastrointestinal lesions. Despite en bloc resection, pathological evaluation of lesions can reveal positive vertical or horizontal margins, which is referred to as R1 resection. Not all R1 lesions referred for surgical resection or endoscopic surveillance show evidence of residual tumor. We aimed to identify the predictors of residual neoplasia in patients with an R1 resection following ESD.

PATIENTS AND METHODS

All lesions resected via ESD between June 2016 and September 2021 at a tertiary referral center were retrospectively identified. Lesions with an R1 resection and adequate follow-up were eligible for inclusion. Patient, lesion, and procedural characteristics were analyzed to identify predictors of residual neoplasia.

RESULTS

Of 614 lesions, 163 (28%) had R1 resection. Of these, 56 lesions in 51 patients had complete follow-up and were included. Thirteen patients (25.5%) underwent surgical resection and the remainder underwent endoscopic surveillance. Seven (12.5%) patients had residual disease. All patients with residual disease had esophageal carcinoma. Positive deep and lateral margins, severe submucosal fibrosis, and moderate/poorly differentiated tumors were identified as significant predictors of residual neoplasia.

CONCLUSION

Most R1 lesions (87.5%) resected by ESD did not have residual disease on follow-up. Those without identified risk factors for residual disease, such as esophageal carcinoma, severe submucosal fibrosis, or both histological margin positivity, may benefit from a strategy of close endoscopic surveillance rather than referral for surgical resection.

Lifestyle Behaviors in Patients With Gastric Cancer: Continuous Need for Alcohol Abstinence and Muscle Strength Training Education

PURPOSE

This study was performed to assess the lifestyle-related behaviors of patients with gastric cancer (GC) and to investigate the associations between the time since GC diagnosis and these behaviors.

MATERIALS AND METHODS

This study included 29,478 adults (including 338 patients with GC) aged ≥ 40 years who participated in the Korea National Health and Nutrition Examination Survey 2014-2021. Multiple logistic regression analysis explored the associations between the time since GC diagnosis (patients diagnosed with GC less than 5 years ago [<5 years group] and those diagnosed with GC 5 or more than years ago [≥5 years group]) and lifestyle factors. Subgroup analyses were conducted based on age and sex.

RESULTS

The current smoking rate was not lower in the GC group than in the healthy group, regardless of time since diagnosis. Compared to the healthy controls, monthly alcohol intake was lower in the <5 years group (odds ratio [OR], 0.450; 95% confidence interval [CI], 0.275-0.736). The ≥5 years group showed a lower rate of strength training (OR, 0.548; CI, 0.359-0.838), compared with the healthy control group. Subgroup analysis focusing on the ≥5 years group revealed a significantly lower rate of strength training, particularly in patients aged ≥65 years and male patients (OR, 0.519 and 0.553; CI, 0.302-0.890 and 0.340-0.901, respectively).

CONCLUSIONS

Clinicians should continue educating patients on lifestyle behavior modifications, particularly alcohol abstinence, even beyond 5 years after GC diagnosis. Education on strength training is especially important for patients ≥65 years or male patients.

Long-term Outcomes of Patients With Early Gastric Cancer Who Had Lateral Resection Margin-Positive Tumors Based on Pathology Following Endoscopic Submucosal Dissection

PURPOSE

Long-term outcomes of patients with positive lateral margins (pLMs) after endoscopic submucosal dissection (ESD) for early gastric cancer (EGC). This study aimed to evaluate the remnant cancer and survival rates of patients with pLMs compared with those who underwent curative resection.

MATERIALS AND METHODS

A retrospective analysis was performed on consecutive patients with pLMs as the only non-curative factor of expanded indication who underwent ESD for EGC with a follow-up duration of 5 years or more. The rates of remnant cancer, recurrence, and survival were analyzed and compared to those of control patients who underwent curative resection by propensity score matching.

RESULTS

Among 3,515 patients treated with ESD between 2005 and 2018, 123 non-curative EGCs were retrospectively analyzed. A total of 108 patients were followed up without endoscopic or surgical resection for 8.2 years. The control group was matched in a 1:1 ratio with patients with EGC who underwent curative resection after ESD. The observation group with pLMs had a higher incidence of remnant cancer (25.9%; 28/108) compared to that in the curative resection group (0/108; P=0.000). The remaining tumors were treated with surgical or endoscopic resection, and no additional recurrences were observed. The overall survival analysis demonstrated no significant difference between the observation and curative resection groups (P=0.577).

CONCLUSIONS

No difference was observed in the overall survival rate between observation and curative resection groups. Therefore, observation may be a possible option for incomplete ESD with pLMs if continuous follow-up is performed.

Esophagectomy versus observation following endoscopic submucosal dissection of pT1b esophageal adenocarcinoma

BACKGROUND

Management following endoscopic submucosal dissection (ESD) of pT1b esophageal adenocarcinoma (EAC) remains controversial. This study compared pathological and survival outcomes of patients after endoscopic resection (ER) of pT1b EAC followed by either en bloc esophagectomy or observation.

METHODS

From 1/12 to 12/22, all patients with pT1b EAC treated with ER were identified from a prospectively maintained departmental database. ESD was curative (all of: Submucosal invasion < 500 μm; G1/2, LVI/PNI-; deep margin-) or non-curative (one or more of Submucosal invasion ≥ 500 μm; G3; LVI/PNI+; deep margin+). Patients were allocated to observation (OBS) or esophagectomy (SURG) based on patient factors/preference and pathological variables.

RESULTS

56/171 ERs met the inclusion criteria. ER was curative in 8/56 (14%) and non-curative in 48/56 (86%). OBS was undertaken after 8/27 (30%) curative and 19/27 (70%) non-curative resections. All 29 SURG patients had non-curative ERs and were younger, had lower Charlson comorbidity scores and had more deep margin + lesions than OBS patients. Post-esophagectomy, 15/29 (52%) had no residual disease within the surgical specimen while pT+N-/pT-N+/pT+N+ occurred in 5/3/6 (17%/10%/21%) patients. Of those with residual disease in the surgical specimen, 12/14 (86%) had deep margin + ERs; however, only ESD instead of EMR was independently associated with a lower risk of residual disease (OR 0.431, 95% CI - 0.016 to 1.234, p = 0.045). OBS and SURG patients had equivalent overall survival outcomes and recurrence was low in both groups even following non-curative ER. Follow-up was 28 months (0-102) and 30 months (0-97), respectively.

CONCLUSION

In select patients, including some of those with a non-curative ESD resection of pT1B EAC, surveillance alone may be appropriate. Alternatives beyond traditional pathological features is needed to direct patient care more accurately.

Early gastric cancer recurrence after endoscopic submucosal dissection: Not to be ignored!

This editorial comments on the article "Efficacy of multi-slice spiral computed tomography in evaluating gastric cancer recurrence after endoscopic submucosal dissection". We focus on the importance of paying more attention to post-endoscopic submucosal dissection (ESD) gastric cancer recurrence in patients with early gastric cancer (EGC) and how to manage it effectively. ESD has been a well-known treatment and the mainstay for EGC, with the advantages of less invasion and fewer complications when compared with traditional surgical procedures. Despite a lower local recurrence rate after ESD, the problem of postoperative recurrence in patients with EGC has become increasingly non-ignorable with the global popularization of ESD technology and the increasing number of post-ESD patients.

Diagnostic accuracy of frozen section biopsy for early gastric cancer extent during endoscopic submucosal dissection: a prospective study

BACKGROUND

Accurate diagnosis of the lateral extent of early gastric cancer during endoscopic submucosal dissection (ESD) is crucial to achieve negative resection margins. Similar to intraoperative consultation with a frozen section in surgery, rapid frozen section diagnosis with endoscopic forceps biopsy may be useful in assessing tumor margins during ESD. This study aimed to evaluate the diagnostic accuracy of frozen section biopsy.

METHODS

We prospectively enrolled 32 patients undergoing ESD for early gastric cancer. Biopsy samples for the frozen sections were randomly collected from fresh resected ESD specimens before formalin fixation. Two different pathologists independently diagnosed 130 frozen sections as "neoplasia," "negative for neoplasia," or "indefinite for neoplasia," and the frozen section diagnosis was compared with the final pathological results of the ESD specimens.

RESULTS

Among the 130 frozen sections, 35 were from cancerous areas, and 95 were from non-cancerous areas. The diagnostic accuracies of the frozen section biopsies by the two pathologists were 98.5 and 94.6%, respectively. Cohen's kappa coefficient of diagnoses by the two pathologists was 0.851 (95% confidence interval: 0.837-0.864). Incorrect diagnoses resulted from freezing artifacts, a small volume of tissue, inflammation, the presence of well-differentiated adenocarcinoma with mild nuclear atypia, and/or tissue damage during ESD.

CONCLUSIONS

Pathological diagnosis of frozen section biopsy is reliable and can be applied as a rapid frozen section diagnosis for evaluating the lateral margins of early gastric cancer during ESD.

Knowledge, attitude, and practice of monitoring early gastric cancer after endoscopic submucosal dissection

BACKGROUND

Early gastric cancer (EGC) is typically treated with endoscopic submucosal dissection (ESD). However, recurrence may occur after ESD, requiring surveillance.

AIM

To examine the knowledge, attitude, and practice (KAP) of EGC survivors following ESD regarding gastric cancer recurrence.

METHODS

This cross-sectional study was conducted between June 1, 2022 and October 1, 2022 in Zhejiang, China. A total of 400 EGC survivors who underwent ESD at the Affiliated Jinhua Hospital, Zhejiang University School of Medicine participated in this study. A self-administered questionnaire was developed to assess KAP monitoring gastric cancer after ESD.

RESULTS

The average scores for KAP were 3.34, 23.76, and 5.75 out of 5, 30, and 11, respectively. Pearson correlation analysis revealed positive and significant correlations between knowledge and attitude, knowledge and practice, and attitude and practice (r = 0.405, 0.511, and 0.458, respectively; all P < 0.001). Multivariate logistic regression analysis showed that knowledge, attitude, 13-24 mo since the last ESD (vs ≤ 12 mo since the last ESD), and ≥ 25 mo since the last ESD (vs ≤ 12 mo since the last ESD) were independent predictors of proactive practice (odds ratio = 1.916, 1.253, 3.296, and 5.768, respectively, all P < 0.0001).

CONCLUSION

EGC survivors showed inadequate knowledge, positive attitude, and poor practices in monitoring recurrences after ESD. Adequate knowledge, positive attitude, and a longer time since the last ESD were associated with practice.

Comparison Trial between I-SCAN-Optical Enhancement and Chromoendoscopy for Evaluating the Horizontal Margins of Gastric Epithelial Neoplasms

Background/Aims

Endoscopic submucosal dissection is a widely used treatment for gastric epithelial neoplasms. Accurate delineation of the horizontal margins is necessary for the complete resection of gastric epithelial neoplasms. Recently, image-enhanced endoscopy has been used to evaluate horizontal margins of gastric epithelial neoplasms. The aim of this study was to investigate whether I-SCAN-optical enhancement (I-SCAN-OE) is superior to chromoendoscopy in evaluating the horizontal margin of gastric epithelial neoplasms.

Methods

This was a multicenter, prospective, and randomized trial. The participants were divided into two groups: I-SCAN-OE and chromoendoscopy. For both groups, we first evaluated the horizontal margins of early gastric cancer or high-grade dysplasia using white-light imaging, and then evaluated, the horizontal margins using I-SCAN-OE or chromoendoscopy. We devised a unique scoring method based on the pathological results obtained after endoscopic submucosal dissection to accurately evaluate the horizontal margins of gastric epithelial neoplasms. The delineation scores of both groups were compared, as were the ratios of positive/negative horizontal margins.

Results

In total, 124 patients were evaluated for gastric epithelial neoplasms, of whom 112 were enrolled in the study. A total of 112 patients participated in the study, and 56 were assigned to each group (1:1). There was no statistically significant difference in the delineation scores between the groups (chromoendoscopy, 7.80±1.94; I-SCAN-OE, 8.23±2.24; p=0.342).

Conclusions

I-SCAN-OE did not show superiority over chromoendoscopy in delineating horizontal margins of gastric epithelial neoplasms.

Local Recurrence after Endoscopic Submucosal Dissection of Early Gastric Cancer

Endoscopic submucosal dissection (ESD) is considered the treatment of choice for early gastric cancer (EGC) with a negligible risk of lymph node metastasis. Locally recurrent lesions on artificial ulcer scars are difficult to manage. Predicting the risk of local recurrence after ESD is important to manage and prevent the event. We aimed to elucidate the risk factors associated with local recurrence after ESD of EGC. Between November 2008 and February 2016, consecutive patients (n = 641; mean age, 69.3 ± 9.5 years; men, 77.2%) with EGC who underwent ESD at a single tertiary referral hospital were retrospectively analyzed to evaluate the incidence and factors associated with local recurrence. Local recurrence was defined as the development of neoplastic lesions at or adjacent to the site of the post-ESD scar. En bloc and complete resection rates were 97.8% and 93.6%, respectively. The local recurrence rate after ESD was 3.1%. The mean follow-up period after ESD was 50.7 ± 32.5 months. One case of gastric cancer-related death (0.15%) was noted, wherein the patient had refused additive surgical resection after ESD for EGC with lymphatic and deep submucosal invasion. Lesion size ≥15 mm, incomplete histologic resection, undifferentiated adenocarcinoma, scar, and the absence of erythema of the surface were associated with a higher risk of local recurrence. Predicting local recurrence during regular endoscopic surveillance after ESD is important, especially in patients with a larger lesion size (≥15 mm), incomplete histologic resection, surface changes of scars, and no erythema of the surface.

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

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

Demarcation Line Determination for Diagnosis of Gastric Cancer Disease Range Using Unsupervised Machine Learning in Magnifying Narrow-Band Imaging

Background and Aims: It is important to determine an accurate demarcation line (DL) between the cancerous lesions and background mucosa in magnifying narrow-band imaging (M-NBI)-based diagnosis. However, it is difficult for novice endoscopists. We aimed to automatically determine the accurate DL using a machine learning method. Methods: We used an unsupervised machine learning approach to determine the DLs. Our method consists of the following four steps: (1) an M-NBI image is segmented into superpixels using simple linear iterative clustering; (2) the image features are extracted for each superpixel; (3) the superpixels are grouped into several clusters using the k-means method; and (4) the boundaries of the clusters are extracted as DL candidates. The 23 M-NBI images of 11 cases were used for performance evaluation. The evaluation investigated the similarity of the DLs identified by endoscopists and our method, and the Euclidean distance between the two DLs was calculated. For the single case of 11 cases, the histopathological examination was also conducted to evaluate the proposed system. Results: The average Euclidean distances for the 11 cases were 10.65, 11.97, 7.82, 8.46, 8.59, 9.72, 12.20, 9.06, 22.86, 8.45, and 25.36. The results indicated that the proposed method could identify similar DLs to those identified by experienced doctors. Additionally, it was confirmed that the proposed system could generate pathologically valid DLs by increasing the number of clusters. Conclusions: Our proposed system can support the training of inexperienced doctors as well as enrich the knowledge of experienced doctors in endoscopy.

Risk Factors and Timing of Additional Surgery after Noncurative ESD for Early Gastric Cancer

BACKGROUND

Patients with early gastric cancer undergoing noncurative endoscopic submucosal dissection (ESD) have a risk of tumor recurrence and metastasis, and some patients need additional surgery. The purpose of this study was to explore the risk factors of cancer residue and lymph node (LN) metastasis after noncurative ESD for early gastric cancer and to compare the short outcome of early and delayed additional surgery.

METHODS

The clinicopathological characteristics of 30 early gastric cancer patients who received noncurative ESD and additional surgery were studied retrospectively. Multivariable regression was utilized to examine the independent risk factors for residual cancer and LN metastasis. Receiver operating characteristic curve was used to analyze the multivariable model's predictive performance. Furthermore, the perioperative safety and radical tumor performance of early surgery (≤30 days, n = 11), delayed surgery (>30 days, n = 11) after ESD, and upfront surgery (n = 59) were compared.

RESULTS

Multivariable regression showed that diffuse type of Lauren classification, submucosal invasion, and positive human epidermal growth factor receptor-2 (HER-2) were risk factors for residual cancer. Undifferentiated carcinoma, vascular invasion, and positive vertical margin were risk factors for LN metastasis. The area under the curve (AUC) of the multifactor model predicting cancer residue and LN metastasis was 0.761 and 0.792, respectively. The early surgery group experienced higher intraoperative blood loss and a longer operation time than the delayed surgery and upfront surgery groups. There was no significant difference in the number of LN dissections, LN metastasis rate, and postoperative complications among the three groups.

CONCLUSION

Diffuse type of Lauren classification, submucosal invasion, and positive HER-2 are risk factors for residual cancer, while undifferentiated carcinoma, vascular invasion, and positive vertical margin are risk factors for LN metastasis. Delayed additional surgery after ESD (>30 days) has higher intraoperative safety, without affecting the radical resection in early gastric cancer patients.

The impact of face shields on the quality of gastrointestinal endoscopy during the COVID-19 pandemic

Background

Coronavirus disease 2019 (COVID-19) has become a global pandemic, with healthcare workers at a high risk of exposure. During this pandemic, endoscopists must wear personal protective equipment (PPE), including face shields, to prevent COVID-19 transmission; however, few studies have reported the impact of face shields on the quality of gastrointestinal (GI) endoscopy. We aimed to determine whether the use of PPE, including face shields, affected the quality of GI endoscopy during the COVID-19 pandemic.

Methods

The medical records of patients who had undergone screening or surveillance colonoscopy and gastric endoscopic submucosal dissection (ESD) at Dong-A University Hospital between June 2020 and March 2021 were retrospectively reviewed. Endoscopists wore isolation gowns, disposable gloves, and KF94 masks from June 2020 to October 2020. From November 2020, endoscopists also wore face shields. We compared GI endoscopy quality indicators between the first five months (no face shields) and the second five months (with face shields). In the non-face shield and face shield groups, we calculated the overall adenoma detection rates (ADRs), polyp detection rate (PDR), sessile serrated lesion detection rate (SSLDR), advanced neoplasia detection rate (ANDR), complete resection rate (CRR), number of polyps and/or adenomas per colonoscopy, and gastric ESD procedure time.

Results

In total, 1359 study patients had undergone screening or surveillance colonoscopy (face shield group, n = 679; non-face shield group, n = 680). No statistically significant between-group differences were observed (PDR, 49.04 vs. 52.50%, p = 0.202; ADR, 38.59 vs. 38.97%, p = 0.884; SSPDR, 1.91 vs. 1.32%, p = 0.388; ANDR, 3.98 vs. 3.97%, p = 0.991, respectively). No difference was found in colonoscopy quality indicators between patients examined by experienced and trainee endoscopists with and without face shields. Of 144 study patients who had undergone gastric ESD for gastric neoplasms, there were 72 patients in each group. No statistically significant differences were found in the CRR (94.44 vs 93.05%, p = 1.000) and procedure times (19.22 ± 9.33 vs. 19.03 ± 11.49, p = 0.911).

Conclusions

Wearing face shields during the COVID-19 pandemic did not affect the quality indicators for GI endoscopy.

Long-term Outcomes of Additional Endoscopic Treatments for Patients with Positive Lateral Margins after Endoscopic Submucosal Dissection for Early Gastric Cancer

Background/Aims

It is uncertain whether additional endoscopic treatment may be chosen over surgery in patients with positive lateral margins (pLMs) as the only non-curative factor after endoscopic submucosal dissection (ESD) for early gastric cancer (EGC). We aimed to compare the long-term outcomes of additional endoscopic treatments in such patients with those of surgery and elucidate the clinicopathological factors that could influence the treatment selection.

Methods

A total of 99 patients with 101 EGC lesions undergoing additional treatment after non-curative ESD with pLMs as the only non-curative factor were analyzed. Among them, 25 (27 lesions) underwent ESD, 29 (29 lesions) underwent argon plasma coagulation (APC), and 45 (45 lesions) underwent surgery. Clinicopathological characteristics and long-term outcomes were compared.

Results

Residual tumor was found in 73.6% of cases. The presence of multiple pLMs was associated with higher risk of residual tumor (p=0.046). During a median follow-up of 58.9 months, recurrent or residual lesions after additional ESD and APC were found in 4% (1/25) and 6.8% (2/29) of patients, respectively. However, all were completely cured with surgery or repeated ESD. There were no extragastric recurrences after additional endoscopic treatment. Lymph node metastasis was identified after additional surgery in one (2.2%) patient with an EGC showing histological heterogeneity.

Conclusions

Given the favorable long-term outcomes, additional ESD or APC may be an acceptable choice for patients with pLMs as the only non-curative factor after ESD for EGC. However, clincopathological characteristics such as multiple pLMs and histological heterogeneity should be considered in the treatment selection.

Endoscopic Closure Utilizing Endoloop and Endoclips After Gastric Endoscopic Submucosal Dissection for Patients on Antithrombotic Therapy

OBJECTIVES

Antithrombotic therapy is a well-known independent risk factor for bleeding after endoscopic submucosal dissection (ESD) of early gastric cancer (EGC). A novel method of ulcer base closure using an endoloop and endoclips has been reported. This study aimed to evaluate the effectiveness of endoscopic closure using an endoloop and endoclips in preventing post-ESD bleeding in patients undergoing gastric ESD on antithrombotic therapy.

METHODS

This was a single center, retrospective study. Patients on antithrombotic therapy who underwent gastric ESD were divided into two groups, the closure group and the non-closure group. We analyzed procedural outcomes, post-ESD bleeding rate and factors associated with post-ESD bleeding.

RESULTS

Among 400 ESDs with EGCs in 311 patients, 131 ESDs in 110 patients were in the closure group, and 269 ESDs in 217 patients were in the non-closure group (16 patients were overlapped in both groups). Post-ESD bleeding rate was 11.5% (15/131) in the closure group, and 11.9% (32/269) in the non-closure group (p = 0.89). Total sustained closure rate during second look endoscopy was 47.8% (33/69). Post-ESD bleeding rate tended to be lower in the closure group than in the non-closure group for lesions located in the greater curvature (3.6% vs. 11.1%, p = 0.11). In addition, sustained closure rate was significantly higher in the greater curvature than in the lesser curvature (72.0% vs. 34.1%, p < 0.01). Multivariate analysis revealed resection size > 40 mm and heparin bridge were the independent risk factor for post-ESD bleeding.

CONCLUSION

Ulcer base closure using endoloop and endoclips did not prevent post-ESD bleeding in patients on antithrombotic therapy.

[Clinical Practice Guideline for Endoscopic Resection of Early Gastrointestinal Cancer]

Although surgery was the standard treatment for early gastrointestinal cancers, endoscopic resection is now a standard treatment for early gastrointestinal cancers without regional lymph node metastasis. High-definition white light endoscopy, chromoendoscopy, and image-enhanced endoscopy such as narrow band imaging are performed to assess the edge and depth of early gastrointestinal cancers for delineation of resection boundaries and prediction of the possibility of lymph node metastasis before the decision of endoscopic resection. Endoscopic mucosal resection and/or endoscopic submucosal dissection can be performed to remove early gastrointestinal cancers completely by en bloc fashion. Histopathological evaluation should be carefully made to investigate the presence of risk factors for lymph node metastasis such as depth of cancer invasion and lymphovascular invasion. Additional treatment such as radical surgery with regional lymphadenectomy should be considered if the endoscopically resected specimen shows risk factors for lymph node metastasis. This is the first Korean clinical practice guideline for endoscopic resection of early gastrointestinal cancer. This guideline was developed by using mainly de novo methods and encompasses endoscopic management of superficial esophageal squamous cell carcinoma, early gastric cancer, and early colorectal cancer. This guideline will be revised as new data on early gastrointestinal cancer are collected.

Current indications for endoscopic submucosal dissection of early gastric cancer

The development of endoscopic treatment technology has further promoted the minimally invasive treatment of early gastric cancer (EGC). Endoscopic treatment has achieved better therapeutic effects in terms of safety and prognosis and is the preferred treatment method for patients who meet the indications for endoscopic treatment. However, the consequent problem is that some patients receiving endoscopic treatment may undergo non-curative resection, and the principle of follow-up management for non-curative resection patients deserves further attention. In addition, there are still debates on how to improve the accuracy of clinical staging, select a reasonable treatment method for patients who meet the expanded indications for endoscopic treatment, manage patients with positive endoscopic surgical margins, conduct research on function-preserving surgery, and manage the treatment of EGC under the current situation in China. Consequently, we aim to review current indications for endoscopic submucosal dissection of EGC in order to better inform treatment options.

Long-term Outcomes of Undifferentiated-Type Early Gastric Cancer with Positive Horizontal Margins after Endoscopic Resection

Background/Aims

This study examined the long-term outcomes of undifferentiated-type early gastric cancer (UD EGC) with positive horizontal margins (HMs) after endoscopic resection (ER) and compared them between additional surgery and nonsurgical management.

Methods

From 2005 to 2015, a total of 1,124 patients with UD EGC underwent ER at 18 tertiary hospitals in Korea. Of them, 92 patients with positive HMs as the only noncurative factor (n=25) or with both positive HMs and tumor size >2 cm (n=67) were included. These patients underwent additional surgery (n=40), underwent additional endoscopic treatment (n=6), or were followed up without further treatment (n=46).

Results

No lymph node (LN) metastasis was found in patients who underwent additional surgery. During a median follow-up of 57.7 months (interquartile range, 27.6 to 68.8 months), no LN or distant metastases or gastric cancer-related deaths occurred in the overall cohort. At baseline, the residual cancer rate was 57.8% (26/45) after additional surgery or ER. The 5-year local recurrence rate was 33.6% among patients who were followed up without additional treatment. The 5-year overall survival rates were 95.0% and 87.8% after additional surgery and nonsurgical management (endoscopic treatment or close follow-up), respectively (log-rank p=0.224). In the multivariate Cox regression analysis, nonsurgical management was not associated with an increased risk of mortality.

Conclusions

UD EGC with positive HMs after ER may have favorable long-term outcomes and a very low risk of LN metastasis. Nonsurgical management may be suggested as an alternative, particularly for patients with old age or chronic illness. (Gut Liver 2021;15-731)

Factors associated with overall survival in early gastric cancer patients who underwent additional surgery after endoscopic submucosal dissection

BACKGROUND

Controversy exists about the benefit of additional surgery after endoscopic submucosal dissection (ESD) for early gastric cancer (EGC).

AIM

To examine risk factors for overall survival (OS) after additional surgery in patients with EGC who initially underwent ESD.

METHODS

This was a retrospective analysis of patients with EGC who underwent additional surgery after ESD at the Beijing Friendship Hospital affiliated to Capital Medical University between August 2012 and August 2019. OS was the primary outcome. Lymph node metastasis and residual tumor were secondary outcomes. Logistic regression models and Kaplan-Meier curves were used for further analysis.

RESULTS

Forty-two patients were evaluated, including 35 (83.3%) males and 7(16.7%) females. The mean age was 62 (range, 32-82) years. Male sex [hazard ratio (HR) = 21.906, 95% confidence interval (CI): 3.762-229.250; P = 0.039), T1b invasion (HR = 3.965, 95%CI: 1.109-17.432; P = 0.047), undifferentiated tumor (HR = 9.455, 95%CI: 0.946-29.482; P = 0.049), lymph node metastasis (HR = 2.126, 95%CI: 0.002-13.266; P = 0.031), and residual tumor (HR = 4.275, 95%CI: 1.049-27.420; P = 0.043) were independently associated with OS. The follow-up duration was 4-81 mo (median: 50.7 mo). OS was 77.0 ± 12.1 mo (95%CI: 53.3-100.7 mo). The 3-year and 5-year OS rates were 94.1% and 85%, respectively.

CONCLUSION

Male sex, T1b invasion, undifferentiated tumor, lymph node metastasis, and residual tumor are independently associated with OS in patients with EGC who underwent additional surgery after ESD.

Recurrence rate of intramucosal gastric cancer with positive vertical margin due to lesion damage during endoscopic submucosal dissection

BACKGROUND AND STUDY AIM

In principle, additional surgery is performed after endoscopic submucosal dissection for early gastric cancer if the vertical margin is positive, regardless of lesion damage. The recurrence rate of vertical margin-positive lesions due to lesion damage after endoscopic submucosal dissection is unknown, and unnecessary surgeries may be performed. In this study, we investigated whether there was a difference in the recurrence rate between vertical margin-positive lesions due to lesion damage and vertical margin-negative lesions.

PATIENTS AND METHODS

We included 1,294 intramucosal gastric cancer lesions that were resected by endoscopic submucosal dissection between January 2008 and December 2016, without additional surgery. The lesions were divided into the Damage and No damage groups based on vertical margin status. The Damage group had only one non-curative indication: a positive vertical margin due to lesion damage. The No damage group had no non curative indications. We compared the recurrence rate between the Damage and No damage groups.

RESULTS

The recurrence rates of the Damage and No damage groups were 0% (0/23; 95% confidence interval: 0-14.8%) and 0% (0/1,271; 95% confidence interval: 0-0.003%), respectively, with no statistically significant difference.

CONCLUSIONS

In intramucosal gastric cancer, the recurrence rate of vertical margin-positive lesions due to lesion damage was 0%, which did not differ from that of vertical margin-negative lesions with curative resection. Follow-up, instead of additional surgery, may be an option for patients with non-curative resection when the only non-curative indication is a positive vertical margin due to lesion damage.

Guidelines for endoscopic submucosal dissection and endoscopic mucosal resection for early gastric cancer (second edition)

In response to the rapid and wide acceptance and use of endoscopic treatments for early gastric cancer, the Japan Gastroenterological Endoscopy Society, in collaboration with the Japanese Gastric Cancer Association, produced "Guidelines for Endoscopic Submucosal Dissection and Endoscopic Mucosal Resection for Early Gastric Cancer" in 2014, as a set of basic guidelines in accordance with the principles of evidence-based medicine. At the time, a number of statements had to be established by consensus (the lowest evidence level), as evidence levels remained low for many specific areas in this field. However, in recent years, the number of well-designed clinical studies has been increasing. Based on new findings, we have issued the revised second edition of the above guidelines that cover the present state of knowledge. These guidelines are divided into the following seven categories: indications, preoperative diagnosis, techniques, evaluation of curability, complications, long-term postoperative surveillance, and histology.

Clinical practice guideline for endoscopic resection of early gastrointestinal cancer

Although surgery was the standard treatment for early gastrointestinal cancers, endoscopic resection is now a standard treatment for early gastrointestinal cancers without regional lymph node metastasis. High-definition white light endoscopy, chromoendoscopy, and image-enhanced endoscopy such as narrow band imaging are performed to assess the edge and depth of early gastrointestinal cancers for delineation of resection boundaries and prediction of the possibility of lymph node metastasis before the decision of endoscopic resection. Endoscopic mucosal resection and/or endoscopic submucosal dissection can be performed to remove early gastrointestinal cancers completely by en bloc fashion. Histopathological evaluation should be carefully made to investigate the presence of risk factors for lymph node metastasis such as depth of cancer invasion and lymphovascular invasion. Additional treatment such as radical surgery with regional lymphadenectomy should be considered if the endoscopically resected specimen shows risk factors for lymph node metastasis. This is the first Korean clinical practice guideline for endoscopic resection of early gastrointestinal cancer. This guideline was developed by using mainly de novo methods and encompasses endoscopic management of superficial esophageal squamous cell carcinoma, early gastric cancer, and early colorectal cancer. This guideline will be revised as new data on early gastrointestinal cancer are collected.

Risk of recurrence when cutting into intramucosal (pT1a) cancer from the cutting-plane side during gastric endoscopic submucosal dissection

BACKGROUND

During endoscopic submucosal dissection (ESD), procedural difficulty and poor visibility of the cutting plane sometimes cause the operator to cut into the lesion from the cutting-plane side, making the vertical margin positive (VM1) or unclear (VMX). In the present study, we evaluated the risk of recurrence of gastric cancer with VM1 /VMX after ESD.

METHODS

In total, 1723 consecutive gastric cancers treated by ESD at Osaka International Cancer Institute from July 2012 to December 2017 were included in this retrospective cohort study. Among them, 231 submucosal or more deeply invasive gastric cancers were excluded because nontechnical factors may contribute to VM1 /VMX in such lesions. To quantify the risk of cutting into cancer from the cutting-plane side during ESD, the proportion of lesions with VM1 /VMX among the pT1a gastric cancers treated by ESD was calculated. The proportion of recurrence among these cases was calculated after exclusion of lesions with positive lymphovascular invasion or a positive horizontal margin in order to eliminate the obvious risk factors for recurrence.

RESULTS

Among 1492 pT1a gastric cancers treated by ESD, 28 lesions (1.9 %; 95 % confidence interval [CI] 1.3 % - 2.7 %) histologically showed VM1 /VMX. No local recurrence (0.0 %; 95 %CI 0.0 % - 12.2 %) occurred among 23 cases. The median follow-up period was 41 months (range 10 - 84 months).

CONCLUSIONS

No local recurrence was detected in pT1a gastric cancers after VM1 /VMX resection by ESD. Surveillance endoscopy could be adopted for such cases without additional surgery.

Total length of positive resection margins can predict remnant gastric cancer following endoscopic submucosal dissection

BACKGROUND

Prediction of remnant tumor is important in determining subsequent treatment options for gastric cancer patients with positive resection margin (RM) after endoscopic submucosal dissection (ESD).

METHODS

Based on the assumption that pathologic factors, including the length and type of involved RM, could potentially predict residual tumor, we evaluated 451 ESD specimens in patients with early gastric cancer.

RESULTS

Of 408 cases, 37 (9.1 %) showed positive RMs. RM involvement in gastric cancer ESD specimens was associated with extended or beyond ESD criteria, greater tumor size, poor differentiation, submucosal invasion, lymphovascular invasion, and upper third location. Among the 37 positive RM cases, residual tumor was present in seven (18.9 %). The presence of residual tumor was not significantly associated with any clinicopathologic parameters except for tumor size and RM status. The total length of the involved RM was the most significant factor associated with the presence of residual tumor (P < 0.008). A total length cut-off value of 6 mm yielded a sensitivity of 85.7 % and negative predictive value of 94.7 % for predicting remnant tumor at gastrectomy following ESD.

CONCLUSIONS

In conclusion, when the ESD specimen exhibits positive RM, a quantitative assessment of the involved RM should be included in the pathology report, as this can help the clinician predict remnant tumor and determine appropriate future treatment.

Guidelines for endoscopic diagnosis of early gastric cancer

The Japan Gastroenterological Endoscopy Society developed the Guideline for Endoscopic Diagnosis of Early Gastric Cancer based on scientific methods. Endoscopy for the diagnosis of early gastric cancer has been acknowledged as a useful and highly precise examination, and its use has become increasingly more common in recent years. However, the level of evidence in this field is low, and it is often necessary to determine recommendations based on expert consensus only. This clinical practice guideline consists of the following sections to provide the current guideline: [I] Risk stratification of gastric cancer before endoscopic examination, [II] Detection of early gastric cancer, [III] Qualitative diagnosis of early gastric cancer, [IV] Diagnosis to choose the therapeutic strategy for gastric cancer, [V] Risk stratification after endoscopic examination, and [VI] Surveillance of early gastric cancer.

Clinical Practice Guideline for Endoscopic Resection of Early Gastrointestinal Cancer

Although surgery was the standard treatment for early gastrointestinal cancers, endoscopic resection is now a standard treatment for early gastrointestinal cancers without regional lymph node metastasis. High-definition white light endoscopy, chromoendoscopy, and image-enhanced endoscopy such as narrow band imaging are performed to assess the edge and depth of early gastrointestinal cancers for delineation of resection boundaries and prediction of the possibility of lymph node metastasis before the decision of endoscopic resection. Endoscopic mucosal resection and/or endoscopic submucosal dissection can be performed to remove early gastrointestinal cancers completely by en bloc fashion. Histopathological evaluation should be carefully made to investigate the presence of risk factors for lymph node metastasis such as depth of cancer invasion and lymphovascular invasion. Additional treatment such as radical surgery with regional lymphadenectomy should be considered if the endoscopically resected specimen shows risk factors for lymph node metastasis. This is the first Korean clinical practice guideline for endoscopic resection of early gastrointestinal cancer. This guideline was developed by using mainly de novo methods and encompasses endoscopic management of superficial esophageal squamous cell carcinoma, early gastric cancer, and early colorectal cancer. This guideline will be revised as new data on early gastrointestinal cancer are collected.

Clinical Practice Guideline for Endoscopic Resection of Early Gastrointestinal Cancer

Although surgery was the standard treatment for early gastrointestinal cancers, endoscopic resection is now a standard treatment for early gastrointestinal cancers without regional lymph node metastasis. High-definition white light endoscopy, chromoendoscopy, and image-enhanced endoscopy such as narrow band imaging are performed to assess the edge and depth of early gastrointestinal cancers for delineation of resection boundaries and prediction of the possibility of lymph node metastasis before the decision of endoscopic resection. Endoscopic mucosal resection and/or endoscopic submucosal dissection can be performed to remove early gastrointestinal cancers completely by <i>en bloc</i> fashion. Histopathological evaluation should be carefully made to investigate the presence of risk factors for lymph node metastasis such as depth of cancer invasion and lymphovascular invasion. Additional treatment such as radical surgery with regional lymphadenectomy should be considered if the endoscopically resected specimen shows risk factors for lymph node metastasis. This is the first Korean clinical practice guideline for endoscopic resection of early gastrointestinal cancer. This guideline was developed by using mainly de novo methods and encompasses endoscopic management of superficial esophageal squamous cell carcinoma, early gastric cancer, and early colorectal cancer. This guideline will be revised as new data on early gastrointestinal cancer are collected.

Salvage endoscopic submucosal dissection for incompletely resected esophageal or gastric neoplasms (case series)

Background and study aims  Given that positive lateral margins indicate possible residual carcinoma, salvage endoscopic submucosal dissection (ESD) should be considered for curative therapy. Presence of submucosal fibrosis, however, makes the procedure difficult to perform. We present our case series to discuss the feasibility of salvage ESD and the timing of the procedure.

Risk Factors and Clinical Outcomes of Non-Curative Resection in Patients with Early Gastric Cancer Treated with Endoscopic Submucosal Dissection: A Retrospective Multicenter Study in Korea

BACKGROUND/AIMS

The purpose of this study was to investigate the risk factors and long-term clinical outcomes of non-curative resection (NCR) in a large-scale patient population.

METHODS

We retrospectively analyzed the clinical data of 3,094 patients who underwent endoscopic submucosal dissection (ESD) of early gastric cancer from March 2005 to March 2018 at 13 institutions in Korea. We analyzed the risk factors for NCR and the survival between patients with curative resection and those with NCR with no additional treatment.

RESULTS

The NCR rate was 21.4% (661/3,094). In multivariate regression analysis, the risk factors affecting NCR with ESD were old age, undifferentiated tumor, tumor location in the upper body, tumor size ≥2 cm, and presence of an ulcer. In Cox proportional hazard regression analysis, tumor size ≥2 cm, submucosal invasion, positive horizontal margin, and lymphovascular invasion were risk factors for local recurrence. In Kaplan-Meier analysis, there was no statistically significant difference in the overall survival between the two groups (log-rank p=0.788). However, disease-specific survival was significantly lower in the NCR group (log-rank p=0.038).

CONCLUSION

Clinicians should be aware of the risk factors for NCR and local recurrence after ESD for early gastric cancer, and should consider providing additional treatment after NCR.

Effect of horizontal margin status and risk of local recurrence after endoscopic submucosal dissection for superficial esophageal cancer

Background and Aim

Endoscopic submucosal dissection (ESD) sometimes results in en bloc resection with a positive or inconclusive horizontal margin (HM1 or HMX, respectively) on histological evaluation. The specific risk for such situations is unclear. We therefore investigated the outcome of ESD with HM1 or HMX.

Methods

This single‐center retrospective study was performed at Osaka International Cancer Institute. A total of 886 esophageal squamous cell carcinoma lesions in 749 patients treated from April 2005 to June 2015 were evaluated according to the following inclusion criteria: en bloc resection with no residual lesion, HM1 or HMX status, no prior treatment, and no additional treatment. We classified HM1 and HMX into type A, in which cancer was exposed on the HM, and type B, in which the HM status was unclear because of mechanical or thermal damage. We further classified type B according to the distance between the cancer and the edge of the specimen: type B1, <1 mm and type B2, ≥1 mm.

Results

The resection margin was judged as HM1 or HMX in 5.0% (39/767; 95% confidence interval, 3.5–6.6%) of the en bloc resected specimens. Of 39 lesions, 30 fulfilled the inclusion criteria. Local recurrence developed in 8 of 30 lesions (26.7%). The local recurrence rates for types A, B1, and B2 were 40% (6/15 lesions), 28.5% (2/7 lesions), and 0.0% (0/8 lesions), respectively.

Conclusions

Although a statistical analysis was not conducted because of the limited events, the pathological HM status may be a useful predictor of local recurrence.

Is Radical Surgery Necessary for All Patients Diagnosed as Having Non-Curative Endoscopic Submucosal Dissection?

If a lesion does not meet the expanded indication criteria for treatment with endoscopic therapy for early gastric cancer or has a positive resection margin, it is regarded as suitable for non-curative resection. Non-curative resection is closely related to the risk of local recurrence, lymph node metastasis, and poor prognosis. If the result is confirmed as non-curative resection, additional treatment should be considered depending on the risks of residual tumor, local recurrence, and lymph node metastasis. As lymphatic invasion is the most important risk factor of recurrence and poor prognosis, surgical treatment should be considered if lymphatic invasion is present. If patients are not suitable for additional surgery owing to old age or coexisting severe disease, close surveillance can be an alternative treatment option.

Endoscopic Submucosal Dissection for the Treatment of Superficial Epithelial Gastric Neoplasia in a Portuguese Centre

Background

The emergence of endoscopic submucosal dissection (ESD) made possible en bloc resection of neoplastic gastric lesions, regardless of lesion size, with reduced rates of complications and recurrence. This technique has become the preferred method for curative resection, instead of conventional endoscopic mucosal resection and surgery, when distant metastases have negligible risk. In Western countries experience with this technique has evolved quickly, with an increasing number of case series reported in the literature. This study aims to report the short- and long-term outcomes of ESD in gastric epithelial neoplastic lesions by a single operator in a Portuguese centre.

Methods

A retrospective analysis of all gastric ESDs in a tertiary specialised unit during a 5-year period, between May 2012 and September 2017, was performed.

Results

A total of 114 ESDs of gastric epithelial lesions were performed during this period; 96.5% of them were removed en bloc and 87.6% with R0 resection. A curative treatment was achieved in 83.2% of the cases. Complications occurred in 13.2% of the procedures, including early and delayed bleeding in 12 patients (10.5%) and one perforation (0.9%). With a median follow-up period of 12 months (interquartile range [IQR] = 18), 6 cases of recurrence at the previous ESD site were diagnosed: 4 residual lesions and 2 local recurrences in previous R0 resections. Residual lesions occurred more often in patients with larger lesions (median = 40.0 mm, IQR = 26 vs. median = 20.0 mm, IQR = 15, p = 0.008) and with positive horizontal margins (HMs) after resection (50.0 vs. 0.0%, Fisher exact test, p < 0.001). The cumulative incidence of metachronous gastric lesions at 34 months was 16.1%. All new lesions were effectively treated using an endoscopic technique. The disease-specific survival at 12 months was 100%.

Conclusion

This study showed that ESD is an effective resection technique for gastric lesions with a good safety profile, confirming other European series. Regardless, high en bloc resection positive HM is still a problem in some specimens resected by ESD. Endoscopic surveillance can detect local recurrence and new lesions during early stages, potentially treatable by endoscopy.

Long-term outcomes after noncurative endoscopic resection of early gastric cancer: the optimal time for additional endoscopic treatment

BACKGROUND AND AIMS

We aimed to evaluate long-term outcomes with noncurative endoscopic submucosal dissection (ESD) for early gastric cancer (EGC) and surveillance strategies such as the optimal time for additional endoscopic treatment in patients with noncurative ESD.

METHODS

Of 2527 patients who underwent gastric ESD for EGC, 512 (20.3%) patients with noncurative resection were reviewed. Noncurative resection is defined as positive resected margins on histology, lymphovascular infiltration, or beyond the expanded criteria for ESD.

RESULTS

The mean ± standard deviation follow-up duration was 79.0 ± 55.7 months. A total of 264 patients (51.6%) and 50 patients (9.8%) underwent surgery and endoscopic treatment after noncurative resection, respectively, whereas 198 patients (38.7%) were observed. Cancer-specific survival and disease-free survival rates were significantly different among the surgery, other endoscopic treatment, and observation groups (96.7%, 86.8%, and 86.2%, respectively; P =.030; and 92.5%, 73.6%, and 63.0%, respectively; P < .001). When patients who underwent surgery were excluded, the disease-free survival rate of recurrence was not significantly different between the endoscopic treatment and observation groups (73.6% vs 63.0%; P = .548). To exclude the potential for the presence of lymph node metastasis, we further analyzed disease-free survival of local recurrence by comparing the patients with only a positive lateral resection margin. The disease-free survival rate was higher in the endoscopic treatment group than in the observation group (89.2% vs 69.1%; P = .023). Moreover, additional endoscopic treatment within 3 months showed significant associations with lower risk of local recurrence on multivariate analysis (hazard ratio, 0.017; 95% confidence interval, 0.002-0.260; P = .003).

CONCLUSIONS

In patients with noncurative ESD, additional surgery showed a better long-term outcome; moreover, when a positive lateral resection margin was the only noncurative factor, additional endoscopic treatment within 3 months could be considered to improve disease-free survival.

Additive endoscopic resection may be sufficient for patients with a positive lateral margin after endoscopic resection of early gastric cancer

BACKGROUND AND AIMS

No well-established treatment strategies exist for lateral margin positivity (LM+) alone after endoscopic resection (ER) of early gastric cancer (EGC). Thus, we aimed to clarify a treatment strategy for non-curative resection (non-CR) with LM+ alone after ER in EGC.

METHODS

Among 2065 patients with EGC treated by ER, 76 (3.6%) with only LM+ after non-CR of EGC were reviewed retrospectively. Of these, 28 underwent gastrectomy, 25 underwent argon plasma coagulation (APC), and 23 underwent repeat ER (re-ER). We analyzed the clinicopathologic characteristics of all patients and compared those who underwent additive surgery, APC, or re-ER.

RESULTS

Of the 76 patients, 28 (36.8%) fulfilled the absolute criteria and 48 (63.2%) the expanded criteria for ER. Among the latter patients, the proportion undergoing additive surgery was 75.0%, higher than that of patients in the former group (P = .014). Residual cancer cells were observed in 70.6% of patients after additive surgery or re-ER. Residual cancer cells were observed significantly more often in patients with undifferentiated-type than in those with differentiated-type EGC (P = .02). However, no lymph node metastasis was observed in any patient after additive surgery.

CONCLUSIONS

Our results suggest that endoscopic treatment may be a sufficient additive therapy for patients with LM+ alone after ER, irrespective of whether the absolute or expanded ER criteria are used. However, as complete ablation of remnant cells cannot be guaranteed, re-ER is a better additive treatment than APC.

[Treatment Strategies after Non-curative Endoscopic Resection of Early Gastric Cancer]

The cases of non-curative endoscopic resection (NCR) of early gastric cancer have increased due to the widespread use of endoscopic submucosal dissection (ESD). NCR is associated with augmenting chances of local recurrence and lymph node metastasis (LNM). Therefore, some additional treatment strategies after NCR are needed. Treatment strategies for NCR should be determined by considering the risk of residual tumor or local recurrence and LNM. Additional surgical treatment such as gastrectomy and lymph node dissection are recommended in patients who have high-risk of LNM. Close observation without additional treatment is considered for selected patients with a less possibility of local recurrence or LNM. Also it may be suggested if there is no or less benefit from surgery in elderly patients or patients with underlying diseases. Additional endoscopic procedures including ESD, endoscopic mucosal resection or argon coagulation therapy are suggested alternatively for highly selected patients not at risk of LNM based on the absolute or expanded criteria of ESD.

Management of early gastric cancer with positive horizontal or indeterminable margins after endoscopic submucosal dissection: multicenter survey

Background and study aims Positive horizontal margins in resected specimens are sometimes encountered after endoscopic submucosal dissection (ESD) for early gastric cancers, and appropriate treatment strategies for these cases are not established. The aim of this study was to evaluate current empirical treatments for patients with positive horizontal or indeterminable margins after ESD. Patients and methods We performed a multicenter survey and data from 14 hospitals were collected. The pooled proportions of positive horizontal or indeterminable margins and those of patients followed up without early intervention were calculated using a logistic-normal random-effects model. For calculating pooled estimates, subgroup analyses of high- and non-high-volume centers were conducted. Results A total of 11,796 ESD cases were enrolled and 229 patients (2 %) had positive horizontal or indeterminable margins. Ninety-eight cases were treated within 30 days of ESD and 131 cases were followed up without early treatments. Pooled estimates of positive margins in high- and non-high-volume centers were 1 % (95 % CI: 1 % - 2 %) and 2 % (95 % CI: 1 % - 4 %), respectively, and were not heterogeneous (P = 0.191). The proportion of patients followed up without early intervention ranged from 30 % to 100 %. The pooled estimate was 68 % (95 % CI: 50 % - 83 %). The pooled estimates of high- and non-high-volume centers were 65 % (95 % CI: 38 % - 85 %) and 72 % (95 % CI: 44 % - 89 %), respectively, and were not heterogeneous (P = 0.692). Conclusion There was insufficient consensus regarding treatment strategies used for early gastric cancer with positive horizontal or indeterminable margins after ESD. Further studies are required to establish a consensus.

Long-term outcomes of endoscopic submucosal dissection for early gastric cancer: a multicenter collaborative study

OBJECTIVE

The indications for endoscopic submucosal dissection (ESD) in patients with early gastric cancer (EGC) have been expanded. However, the long-term outcomes of ESD remain unclear. We retrospectively investigated the long-term outcomes of ESD in patients with EGC.

METHODS

We retrospectively studied patients with EGC who underwent ESD at 11 institutions between January 2003 and December 2010. A total of 6456 patients (7979 lesions) who met the absolute indications for ESD and 4202 patients (5781 lesions) who met the expanded indications for ESD were studied. Clinicopathological features, clinical course, and outcomes were studied in 67 patients in whom local recurrence or metastatic recurrence was diagnosed as of March 31, 2014. The median follow-up period was 56 months.

RESULTS

Local recurrence was diagnosed in 14 patients (0.22%) who met the absolute indications and 53 patients (1.26%) who met the expanded indications. The rate of local recurrence was significantly higher in patients with expanded-indication lesions (p < 0.05). As additional treatment for recurrence, most patients received endoscopic treatment. Metastatic recurrence did not develop in any patient with absolute-indication lesions, but was diagnosed in 6 patients (0.14%) with expanded-indication lesions (p < 0.05). The histological type was undifferentiated mixed type in half the patients. Three patients died of primary gastric cancer.

CONCLUSIONS

ESD for expanded-indication lesions of EGC is considered an effective therapy associated with an extremely low rate of metastatic recurrence on long-term follow-up. However, fully informed consent concerning the risk of metastatic recurrence should be obtained before ESD, and close postoperative follow-up is essential.

Learning curve and clinical outcome of gastric endoscopic submucosal dissection performed by trainee operators

BACKGROUND

Although endoscopic submucosal dissection (ESD) represents a significant progress in therapeutic endoscopy, little is known about how trainees attain its technical proficiency. The aims of this study were to evaluate the learning curve and clinical outcomes of gastric ESD performed by trainee endoscopists.

METHODS

Between April 2009 and March 2014, 334 gastric ESD procedures were performed by seven trainees (42-50 consecutive cases per trainee). The learning curve for gastric ESD was evaluated using the cumulative sum (CUSUM) method. Long-term outcomes were also analyzed.

RESULTS

The calculated CUSUM learning curve comprised three phases: Phase I (the initial 15 cases), Phase II (the middle 15 cases), and Phase III (the final 20 cases). The resection speed was 5.7 ± 3.2 min/cm² in Phase I, 4.7 ± 2.7 min/cm² in Phase II, and 4.3 ± 2.2 min/cm² in Phase III. The resection speed was significantly faster in Phase II than in Phase I (p = 0.019). The rate of self-completion reached more than 95% in Phases II and III. The overall complete resection rate was 95%, showing no significant differences between the three phases. Local recurrence was diagnosed in none of the patients during a median follow-up of 38 months.

CONCLUSIONS

For the trainees, 30 cases were required to attain a higher technical level of competence in gastric ESD. After the learning curve phase, trainee operators could be expected to complete the procedure successfully with favorable long-term outcomes.

Evaluation and Management of Gastric Superficial Neoplastic Lesions

Gastric cancer is one of the most common and lethal cancers in the world. In Portugal, it is a major health problem presenting one of the highest incidence rates among European countries. In most Western countries, gastric cancer is generally diagnosed in advanced stages. Nevertheless, with the widespread use of upper endoscopy, gastric superficial neoplastic lesions are being increasingly recognized and diagnosed. However, there are no clear recommendations regarding who should be screened for its presence and only recently guidelines concerning the evaluation and management of these lesions were published. In this review, we summarize the current scientific evidence regarding diagnosis and management of gastric superficial neoplastic lesions. Topics like screening, diagnosis, endoscopic evaluation, management, treatment, pathologic evaluation and follow-up of patients with these lesions are covered and areas of future research are discussed. Whenever possible, evidence-based recommendations are made, and on the other cases expert opinion is presented.

Risk stratification and predictive risk-scoring model for lymph node metastasis in early gastric cancer

BACKGROUND

We are increasingly experiencing difficulty in deciding whether to perform gastrectomy after noncurative endoscopic resection of early gastric cancer (EGC) for patients at high risk for surgery. If the differences in risk for lymph node metastasis (LNM) on the basis of noncurative status are understood, the decision becomes easier. The present study aimed to stratify the LNM risk and develop and validate a risk-scoring model for predicting LNM.

METHODS

By retrospectively reviewing 3131 patients with solitary EGC who underwent gastrectomy with lymphadenectomy at our institution between July 1997 and May 2013, LNM risk was stratified and a risk-scoring model was developed on the basis of the identified independent risk factors for LNM. The scoring was validated using 352 other surgically resected EGC cases. The discriminatory accuracy of the scoring was measured by area under receiver operating characteristic curve (AUROC).

RESULTS

LNM was detected in 386 of 3131 cases. LNM risk in each subgroup, stratified by the identified independent risk factors, such as tumor size, depth, histological type, ulcerative findings, and lymphovascular involvement, considerably varied from 0 % to >50 % even among the current guidelines' noncurative subgroups. An 11-point scoring model was built, and AUROCs were 0.84 (95 % confidence interval, 0.82-0.86) and 0.82 (0.75-0.88) in the development and validation sets, respectively.

CONCLUSIONS

The present study revealed detailed LNM risk stratification data, and developed and validated an 11-point scoring model.

Treatment Strategy after Incomplete Endoscopic Resection of Early Gastric Cancer

Endoscopic resection of early gastric cancer is defined as incomplete when tumor cells are found at the resection margin upon histopathological examination. However, a tumor-positive resection margin does not always indicate residual tumor; it can also be caused by tissue contraction during fixation, by the cautery effect during endoscopic resection, or by incorrect histopathological mapping. Cases of highly suspicious residual tumor require additional endoscopic or surgical resection. For inoperable patients, argon plasma coagulation can be used as an alternative endoscopic treatment. Immediately after the incomplete resection or residual tumor has been confirmed by the pathologist, clinicians should also decide upon any additional treatment to be carried out during the follow-up period.

Factors associated with incomplete gastric endoscopic submucosal dissection due to misdiagnosis

BACKGROUND AND STUDY AIMS

Endoscopic submucosal dissection (ESD) is widely accepted for treating early gastric cancer (EGC); however, there can be cases of incomplete resection due to not only technical problems, but also misdiagnosis. Our aim was to identify factors associated with incomplete gastric ESD due to misdiagnosis.

PATIENTS AND METHODS

A total of 2,268 patients with solitary EGCs at initial onset underwent ESD with curative intent at our hospital from 1999 to 2008. We retrospectively assessed the clinicopathological factors by comparing the two groups of incomplete ESD cases due to misdiagnosis (cases with a positive lateral margins [LM] [Group A] or those with a positive vertical margins [VM] [Group B]) with complete ESD cases using multivariable analysis.

RESULTS

Complete ESD was achieved in 2,097 patients. The 171 patients with incomplete ESDs were divided into 109 with a positive LM and 80 with a positive VM (overlapped). Except 49 cases with a positive LM due to technical problems, a positive LM due to misdiagnosis was identified in 60 cases (Group A). Excluding 32 cases with a positive VM due to technical problems, a positive VM due to misdiagnosis was found in 48 cases (Group B). Significant independent factors (odds ratios [OR]; 95 % confidence intervals [CI]) for each group were as follows: Group A: size > 20 mm (5.4; 3.0 - 9.9), undifferentiated-type (4.1; 1.8 - 9.0), submucosal invasion (2.0; 1.1 - 3.4) and location of upper/middle (1.9; 1.0 - 3.6); Group B: size > 20 mm (3.0; 1.6 - 5.5), undifferentiated-type (3.0; 1.1 - 8.0) and location of upper/middle (2.4; 1.2 - 4.8).

CONCLUSIONS

Endoscopists must be aware of these factors associated with incomplete gastric ESD due to misdiagnosis to further decrease their incidence.

Relevant risk factors for positive lateral margin after en bloc endoscopic submucosal dissection for early gastric adenocarcinoma

OBJECTIVE

This study aimed to systematically assess the relevant risk factors of positive lateral margin (LM) after en bloc resection of early gastric adenocarcinoma.

METHODS

A total of 242 patients who had undergone endoscopic submucosal dissection (ESD) due to early gastric lesions from January 2009 to March 2015 were included in the study. Clinicopathological features of the lesions and the risk factors related to positive LM were analyzed.

RESULTS

The curative rate was 82.2% and positive LM was found in 12.4% of the lesions. Univariate analysis showed that positive LM was significantly associated with the tumor location (at the upper third of the stomach), size (>3 cm), histological findings, the presence of lymphovascular invasion and deeper invasion depth. Moreover, positive LM had a higher incidence of recurrent or residual tumors. A multivariate analysis showed that the location, tumor size and histological classification of tumors were independent risk factors for positive LM.

CONCLUSIONS

Positive LM is closely related to the upper third of stomach, a tumor larger than 3 cm and a mixed-type carcinoma. Additionally, positive LM has a predilection for recurrent or residual tumors.

The Japanese Viewpoint on the Histopathology of Early Gastric Cancer

Japanese histopathologists have traditionally had greater opportunity to study the histology and clinical course of early gastric cancer because of technological developments including double contrast radiography and endoscopy systems, combined with the higher incidence of gastric cancer in the general population in Japan. Endoscopic resection is now considered best practice for treatment of early gastric cancers with a negligible risk of lymph node metastasis. Histopathologic evaluation plays a critical role in assessing the likelihood of lymph node metastasis on endoscopically resected specimens. There remains disparity between Western and Japanese histopathologists in the conceptual approach to the histopathologic evaluation of neoplastic lesions in the upper gastrointestinal tract, in particular regarding lesions straddling the borderline between noninvasive and invasive disease. Although in routine practice, the clinical impact of these conceptual differences is small, this disparity does complicate international exchange of datasets and the development of globally applicable formal definitions. Here we review the current practice in histological diagnosis of early gastric cancer in Japan and discuss some of the conceptual differences between Japanese and Western histopathological assessment of lesions in the neoplastic stomach.

A systematic review and meta-analysis on outcomes after Rx or R1 endoscopic resection of superficial gastric cancer

OBJECTIVE

Endoscopic resection is a standard treatment for gastric superficial lesions. A positive or a nonevaluable margin is considered a noncurative criterion. We aimed to systematically review recurrence, residual disease, lymph node metastasis (LNM) and cancer-related death following Rx/R1 resection of gastric lesions in the absence of other noncurative criteria.

MATERIALS AND METHODS

MEDLINE systematic review and meta-analysis by July 2014.

RESULTS

Data were extracted from 31 manuscripts. Definitions and results differed significantly. However, nonevaluable (HMx) and positive horizontal margins (HM1) were associated with 10% [95% confidence interval (CI) 5-15%] and 36% (95% CI 24-48%) rates of recurrence/residual disease, respectively, with an odds ratio of 2.85 (95% CI 1.6-5.8, P<0.01) for HM1 compared with HMx. Nonevaluable (VMx) or positive (VM1) vertical margin was associated with a 43% (95% CI 17-68%) rate of recurrence/residual. VMx/VM1 was associated with a higher risk of recurrence/residual compared with HMx/HM1 (odds ratio 3.76, 95% CI 1.71-6.82, P<0.01). The most common strategy after HMx/HM1 was endoscopic surveillance and retreatment, whereas surgery was recommended after VMx/VM1. No cases of LNM or cancer-related death were noticeable if neither submucosal invasion more than 500 µm nor lymphovascular infiltration was also reported.

CONCLUSION

Rx/R1 resection in the absence of other noncurative criteria does not appear to be a significant risk factor for LNM or cancer-related death. The risk of recurrence/residual disease is higher after HM1 than HMx and higher after VMx/VM1 than HMx/HM1. However, considerable heterogeneity was found in studies. Standard definitions should be created and applied in future studies.

Clinicopathological significance of orphan nuclear receptor Nurr1 expression in gastric cancer

BACKGROUND

Gastric cancer is the fourth most common cancer and the second leading cause of cancer-related deaths worldwide. Gastric cancer is characterized by high levels of invasion and metastasis. Increasing attention is being focused on discovering molecular markers for the diagnosis of gastric cancer and for predicting its prognosis. The objective of the present study was to evaluate Nurr1 expression in gastric cancer and to assess its correlation with clinicopathological parameters and prognosis in gastric cancer patients.

METHODS

Tissue samples were obtained from 120 gastric cancer patients. We investigated Nurr1 expression in human normal and gastric cancer tissues using real-time reverse transcription polymerase chain reaction (qRT-PCR), western blotting, and immunohistochemistry. We determined the association between Nurr1 and recurrence, prognosis and patient clinicopathological parameters. Univariate and multivariate survival analyses with a Cox's proportional hazards regression model were used to identify independent factors related to recurrence and prognosis.

RESULTS

The immunohistochemical, qRT-PCR and western blot analyses revealed that Nurr1 expression was increased in gastric cancer tissues compared with normal gastric tissue (P < 0.05). Nurr1 expression was significantly correlated with the tumor size, depth of tumor invasion, lymph node metastasis, recurrence, and distant metastasis of gastric cancer (P < 0.05). Moreover, Nurr1-high patients also exhibited poorer overall survival (OS) and disease-free survival compared with Nurr1-low patients (P < 0.01). The univariate and multivariate survival analyses suggested that Nurr1 expression (P = 0.011), histology (P = 0.018), depth of tumor invasion (P = 0.037), and presence of lymph node metastasis (P = 0.031) were independent prognostic factors for recurrence. In addition, Nurr1 expression (P = 0.007), depth of tumor invasion (P = 0.014), lymph node metastasis (P = 0.044), distant metastasis (P = 0.023), and recurrence (P = 0.011) were independent prognostic factors of OS in gastric cancer patients.

CONCLUSIONS

The Nurr1 protein may be useful as a marker of recurrence, metastasis, and poor prognosis following curative resection in patients with gastric cancer.