Risk factors and management of positive horizontal margin in early gastric cancer resected by en bloc endoscopic submucosal dissection

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.

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.

Low recurrence rate after endoscopic resection in non-ampullary duodenal lesions: A 16-year single-center retrospective study

Endoscopic resection (ER) for non-ampullary duodenal lesions (NADLs) is technically more difficult than lesions of the stomach. However, endoscopic treatment of duodenal lesions has been increasingly performed in recent years. This study aimed to evaluate the efficacy and safety of ER for NADLs.Patients who underwent ER for NADLs between 2004 and 2019 were retrospectively reviewed. Clinical and pathologic features of the lesions including the clinical outcomes and adverse events were analyzed.The study included 80 patients with NADLs. The mean age of patients was 59.3 years (22-80 years), the mean size of the lesion was 8.8 ± 7.0 mm, and the mean procedure time was 13.2 ± 11.2 min. Half (40/80) of the lesions were in the duodenal bulb including the superior duodenal angle. Final histological data showed 56 adenomas (70.5%), 13 Brunner gland tumors (16.2%), and 4 pyloric gland tumors (5.0%). The final diagnoses of 5 lesions after ER showed higher-grade dysplasia compared to pre-ER biopsy findings. The en bloc resection rate was 93.8% (75/80), and the complete resection rate with clear margins was 90.0% (72/80). Micro-perforation occurred in 2 of 80 patients and was successfully treated with conservative treatment. There were no cases of delayed bleeding. The mean follow-up period was 27.0 months (2-119 months) with no cases of recurrence.ER may be an effective treatment for NADLs with favorable long-term outcomes. However, the possibility of perforation complications should always be considered during ER.

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.

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.

Gastric endoscopic submucosal dissection: a systematic review and meta-analysis on risk factors for poor short-term outcomes

OBJECTIVE

Endoscopic submucosal dissection (ESD) is now established as the first option to manage early gastric neoplasms, but its efficacy may vary according to diverse factors. We aimed to systematically identify risk factors for poor short-term outcomes of gastric ESD with the purpose to improve patients' selection and management.

METHODS

Three online databases (MEDLINE, ISI Web of Knowledge and Scopus) were searched (last search on June 2018) for poor outcomes of gastric ESD (deep submucosal invasion, piecemeal/incomplete resection, noncurative resection and local recurrence).

RESULTS

One hundred five studies were included referring to 52.126 ESDs. Undifferentiated histology and upper location (vs lower) were associated with submucosal invasion [odds ratio (OR) = 2.42 [95% confidence interval (CI), 1.62-3.61] and OR = 3.20 (1.04-9.86), respectively] and deep submucosal invasion [OR = 2.98 (2.02-4.39) and OR = 2.35 (1.45-3.81), respectively]. Lesion size greater than 30 mm and ulceration were associated with piecemeal resection [OR = 2.78 (1.17-6.60) and OR = 2.76 (1.23, 6.20), respectively]. Lesion size greater than 30 mm, ulceration, upper location and fibrosis were risk factors for incomplete resection [OR = 3.83 (2.68-5.49), OR = 4.06 (1.62-10.16), OR = 3.71 (2.49-5.54) and OR = 4.46 (1.66-11.96), respectively]. A noncurative resection was more often observed for lesions located in the upper third of the stomach [OR = 1.49 (1.24-1.79)], depressed morphology [OR = 1.49 (1.04-2.12)] and those outside standard criteria [OR = 3.56 (2.31-5.48)]. Older age was significantly linked with local recurrence rates [OR = 3.08 (1.13-5.02)].

CONCLUSION

Several risk factors influence poor efficacy short-term outcomes of gastric ESD that may be used to inform both patients and health providers about the expected efficacy.

Additional gastrectomy in early-stage gastric cancer after non-curative endoscopic resection: a meta-analysis

Background and objective

The role of additional gastrectomy after non-curative endoscopic resection remains uncertain. The present meta-analysis aimed to explore the risk factors for early-stage gastric-cancer patients after non-curative endoscopic resection and evaluate the efficacy of additional gastrectomy.

Methods

Relevant studies that reported additional gastrectomy after non-curative endoscopic resection were comprehensively searched in MedLine, Web of Science and EMBASE. We first investigated the risk factors for residual tumor and lymph-node metastasis after non-curative endoscopic resection and then analysed the survival outcome, including 5-year overall survival (OS) and 5-year disease-free survival, of additional gastrectomy.

Results

Twenty-one studies comprising 4870 cases were included in the present study. We found that residual tumor was associated with larger tumor size (>3 cm) (odds ratio [OR] = 2.81, P < 0.001), undifferentiated tumor type (OR = 1.78, P = 0.011) and positive horizontal margin (OR = 9.78, P < 0.001). Lymph-node metastasis was associated with larger tumor size (>3 cm) (OR = 1.73, P < 0.001), elevated tumor type (OR = 1.60, P = 0.035), deeper tumor invasion (>SM1) (OR = 2.68, P < 0.001), lymphatic invasion (OR = 4.65, P < 0.001) and positive vertical margin (OR = 2.30, P < 0.001). Patients who underwent additional gastrectomy had longer 5-year OS (hazard ratio [HR] = 0.34, P < 0.001), 5-year disease-free survival (HR = 0.52, P = 0.001) and 5-year disease-specific survival (HR = 0.50, P < 0.001) than those who did not. Moreover, elderly patients also benefited from additional gastrectomy regarding 5-year OS (HR = 0.41, P = 0.001).

Conclusions

Additional gastrectomy with lymph-node dissection might improve the survival of early-stage gastric-cancer patients after non-curative endoscopic resection. However, risk stratification should be performed to avoid excessive treatment.

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.

Comparison of the safety of the application of painless gastroscopy and ordinary gastroscopy in chronic hypertension patients combined with early gastric cancer

The aim of the present study was to compare the safety of the application of painless gastroscopy and ordinary gastroscopy for chronic hypertension patients combined with early gastric cancer. A total of 123 patients with early gastric cancer were selected at the Dongying People's Hospital from June, 2014 to August, 2016. The patients were randomly divided into the painless (n=63) and ordinary (n=60) gastroscopy groups. Proper pretreatment was performed according to whether anesthesia was performed or not. Arterial pressure, heart rate, and blood oxygen saturation were detected and compared before anesthesia, when gastroscope passed through the esophageal entrance plane, and after recovery from anesthesia. The incidence of nausea and vomiting, cough, dysphoria, throat discomfort and other adverse reactions during and after surgery were recorded and compared. Compared with the levels before anesthesia, the mean arterial pressure, heart rate and blood oxygen saturation were significantly reduced in painless gastroscopy when the gastroscope passed through the esophageal entrance plane (P<0.05). In the ordinary gastroscopy group, the mean arterial pressure, heart rate and blood oxygen saturation were significantly increased when the gastroscope passed through the esophageal entrance plane compared with the levels before anesthesia (P<0.05). Blood pressure decreased in the painless gastroscopy group whereas it increased in the ordinary gastroscopy group after anesthesia. The decrease in the painless gastroscopy group was lower than in the ordinary group. The incidence of intraoperative and postoperative adverse reactions including nausea, vomiting, cough, dysphoria, pharyngeal discomfort and other adverse reactions was significantly decreased in the painless gastroscopy group than in the ordinary gastroscopy group (P<0.05). The results suggest that the application of painless gastroscopy in chronic hypertension patients can significantly reduce the incidence of intraoperative and postoperative adverse reactions compared with that of the Gastric cancer ordinary gastroscopy. Thus, painless gastroscopy is safer than ordinary gastroscopy.

Risk-Stratification Model Based on Lymph Node Metastasis After Noncurative Endoscopic Resection for Early Gastric Cancer

BACKGROUND

Patients with early gastric cancer (EGC) who have undergone noncurative endoscopic resection (ER) generally require additional surgery due to the possibility of lymph node metastasis (LNM). This study aimed to develop a reliable risk-stratification system to predict LNM after noncurative ER for EGC.

METHODS

A total of 2368 patients had a diagnosis of EGC and underwent ER. The study analyzed 321 patients who underwent additive gastrectomy and lymph node dissection after noncurative ER. Independent risk factors for LNM were identified and used to develop a risk-stratification system to estimate the relative risk of LNM.

RESULTS

Of the 321 patients, 23 (7.2%) had LNM. A logistic regression analysis showed that female sex, lymphovascular invasion (LVI), and a positive vertical margin were significantly associated with LNM. The authors established a risk-stratification system using sex, LVI, and positive vertical margin (area under the receiver-operating characteristic [AUROC] curve, 0.811). The high-risk LNM group (score, ≥ 2 points) showed a significantly higher risk of LNM than the low-risk LNM group (score, <2 points) (14.0 vs 1.2%). No LNM was found in patients with a risk score of zero. After internal and external validation, the AUROC curve for predicting LNM was 0.788 and 0.842, respectively.

CONCLUSIONS

The risk-stratification system developed in this study will facilitate identification of patients who should undergo LN dissection after noncurative ER. Although additive surgery should be performed after noncurative ER for patients with a high risk of LNM, a close follow-up visit could be considered for low-risk patients with multiple comorbidities or high operative risks.

Additional surgical resection after endoscopic mucosal dissection for early gastric cancer: A medium-sized hospital's experience

PURPOSE

In Japan, the majority of early gastric cancers (EGCs) are now treated with endoscopic submucosal dissection (ESD). Patients with non-curative lesions treated by ESD are advised to undergo additional surgical resection (ASR) based on guidelines from the Japan Gastroenterological Endoscopy Society (JGES) and Japanese Gastric Cancer Association (JGCA). However, many studies have demonstrated that residual cancer and lymph node metastasis are only rarely found in ASR specimens. Here we retrospectively analyzed the conditions that could enable the avoidance of unnecessary ASR.

METHODS

The ESD data for 114 absolute indication lesions and 26 lesions of expanded indication lesions were analyzed. The indications and the curability were evaluated according to the JGES/JGCA guidelines.

RESULTS

The rates of non-curative resection and ASR were significantly higher in the expanded indication group compared to the absolute indication group (26.9% and 19.2% vs. 7.9% and 0.9%, respectively). ASR was performed for six patients. Three of their ARS specimens contained neither residual cancer nor lymph node metastasis, and the pathological findings of the preceding ESD specimens deviated slightly from the curative criteria defined by the guidelines. The conditions of the lesions that did not meet the curative criteria were as follows: (1) sm1 invasion of undifferentiated-type lesion <10 mm dia., (2) 21-25 mm dia. mucosal undifferentiated-type lesion, or (3) peacemeal resection with a horizontal margin positive for the mucosal differentiated-type.

CONCLUSIONS

These data suggest that a close follow-up without ASR might be appropriate for patients in the above-mentioned three categories after non-curative ESD for EGC.

Useful condition of chromoendoscopy with indigo carmine and acetic acid for identifying a demarcation line prior to endoscopic submucosal dissection for early gastric cancer

Background

Identifying a precise demarcation line (DL) is indispensable for pathological complete en bloc endoscopic submucosal dissection (ESD) for early gastric cancer (EGC). We evaluated the useful condition of chromoendoscopy with indigo carmine and acetic acid for marking dots around lesions before ESD for EGC.

Methods

We examined 98 consecutive patients with 109 intramucosal EGCs (mean diameter, 17.8 ± 12.4 mm; main histologic type, 96 intestinal and 13 diffuse) resected by en bloc ESD after chromoendoscopy with indigo carmine and acetic acid between December 2012 and February 2014. The DL was identified by this technique just before ESD (mean chromoendoscopy observation time, 71.6 s); subsequently, marking dots were placed around the EGC. EGCs were classified into two groups: useful for identifying the DL or useless. Clinicopathological characteristics and clinical outcomes were evaluated in each group.

Results

Forty-two of the 109 cases (38.5 %) were determined useful for chromoendoscopy with indigo carmine and acetic acid. Multivariate analysis with logistic regression showed that macroscopic type (protruded or flat elevated-type) and atrophic border (the oral side of tumor) were independently associated with the usefulness of chromoendoscopy using indigo carmine and acetic acid for identifying the DL of EGCs (P < 0.05). The histologically positive horizontal margin after ESD was 0 % (0/42) in useful cases, and 7.5 % (5/67) in useless cases.

Conclusions

Before ESD, chromoendoscopy with indigo carmine and acetic acid can be used for creating precise markings in protruded or flat elevated-type EGC or at the atrophic border on the oral side of EGCs.

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.

Additional surgery for non-curative resection after endoscopic submucosal dissection for gastric cancer: a retrospective analysis of 200 cases

PURPOSE

Endoscopic submucosal dissection is recommended for early gastric cancer with a low risk of lymph node metastasis. When the pathological findings do not meet the curative criteria; then, an additional gastrectomy with lymph node dissection is recommended. However, most cases have neither lymph node metastasis nor a local residual tumor during an additional surgery.

METHODS

This was a single-institutional retrospective cohort study, analyzing 200 patients who underwent an additional gastrectomy after non-curative endoscopic submucosal dissection from January 2005 to October 2015. We reviewed the patients' clinicopathological data and evaluated the predictors for the presence of a residual tumor.

RESULTS

Histopathology revealed lymph node metastasis in 15 patients (7.5 %) and a local residual tumor in 23 (11.5 %). A multivariable analysis revealed macroscopic findings (flat/elevated type) (p = 0.011, odds ratio = 4.63), lymphatic invasion (p < 0.0001, odds ratio = 14.2), and vascular invasion (p = 0.04, odds ratio = 4.00) to be predictors for lymph node metastasis. A positive vertical margin (p = 0.0027, odds ratio = 3.26) and horizontal margin (p = 0.0008, odds ratio = 5.74) were predictors for a local residual tumor. All cases with lymph node metastasis had lymphovascular invasion with at least one other non-curative factor.

CONCLUSIONS

The risk of a residual tumor can, therefore, be estimated based on the histopathology of endoscopic submucosal dissection samples. Lymphovascular invasion appears to be a pivotal predictor of lymph node metastasis.

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.

Endoscopic color doppler ultrasonography in predicting the safety of endoscopic submucosal dissection for antral heterotopic pancreas

BACKGROUND/AIMS

Complications are important determining factors for safety of endoscopic submucosal dissection (ESD) for gastric heterotopic pancreas (HP). This study investigated whether endoscopic color Doppler ultrasonography (ECDUS) could be used to predict the feasibility, efficacy, and safety of ESD.

PATIENTS AND METHODS

The study included 52 patients with heterotopic pancreas of the gastric antrum who underwent ECDUS before ESD. ECDUS was used to evaluate the submucosal vascular structure and the location of HP in gastric wall. The patients who had a vessel at least 500 μm in diameter or at least 10 vascular structures per field of view were classified into the rich group (Group R), and others were classified into the non-rich group (Group N). Procedure time, decrease in hemoglobin, frequency of clip use, complications, recurrence rate, and others were retrospectively evaluated.

RESULTS

There were 18 patients in Group R and 34 patients in Group N. Mean procedure time was significantly longer in group R (55.4 min) than in group N (35.5 min) (P = 0.014). The incidence of muscle injury and clip use were significantly higher in group R (77.8/83.3%) than in group N (20.6/23.5%) (P < 0.05). Mean decrease in hemoglobin was 2.5 g/dL in group R and 2.4 g/dL in group N, with no significant difference. There were no recurrences in any cases during the follow-up period.

CONCLUSION

Preoperative identification of submucosal vascular structure by ECDUS can predict procedure time and the incidence of muscle injury and clip use, which is particularly suitable for predicting ESD safety in heterotopic pancreas of stomach.

Clinicopathological characteristics of clinical early gastric cancer in the upper-third stomach

AIM: To elucidate the clinicopathological characteristics of clinically early gastric cancer in the upper-third stomach and to clarify treatment precautions.

METHODS: A total of 683 patients with clinical early gastric cancer were enrolled in this retrospective study, 128 of whom had gastric cancer in the upper-third stomach (U group). All patients underwent a double contrast barium examination, endoscopy, and computed tomography (CT), and were diagnosed preoperatively based on the findings obtained. The clinicopathological features of these patients were compared with those of patients with gastric cancer in the middle- and lower-third stomach (ML group). We also compared clinicopathological factors between accurate-diagnosis and under-diagnosis groups in order to identify factors affecting the accuracy of a preoperative diagnosis of tumor depth.

RESULTS: Patients in the U group were older (P = 0.029), had a higher ratio of males to females (P = 0.015), and had more histologically differentiated tumors (P = 0.007) than patients in the ML group. A clinical under-diagnosis occurred in 57 out of 683 patients (8.3%), and was more frequent in the U group than in the ML group (16.4% vs 6.3%, P < 0.0001). Therefore, the rates of lymph node metastasis and lymphatic invasion were slightly higher in the U group than in the ML group (P = 0.071 and 0.082, respectively). An under-diagnosis was more frequent in histologically undifferentiated tumors (P = 0.094) and in those larger than 4 cm (P = 0.024). The median follow-up period after surgery was 56 mo (range, 1-186 mo). Overall, survival and disease-specific survival rates were significantly lower in the U group than in the ML group (P = 0.016 and 0.020, respectively). However, limited operation-related cancer recurrence was not detected in the U group in the present study.

CONCLUSION: Clinical early gastric cancer in the upper-third stomach has distinguishable characteristics that increase the risk of a clinical under-diagnosis, especially in patients with larger or undifferentiated tumors.

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.

Endoscopic prediction of tumor margin and invasive depth in early gastric cancer

Gastric cancer (GC) is the fifth most common cancer and the third leading cause of cancer-related deaths in the world. The prognosis of GC is clearly associated with the tumor stage, with a 5-year overall survival rate for early gastric cancer (EGC) exceeding 90%, which is significantly higher than that of advanced gastric cancer. Endoscopic resection, including endoscopic mucosal resection and endoscopic submucosal dissection, has been adopted in recent decades as the first treatment option of EGC in many countries for its minimal invasion and high curative rate. However, the horizontal and vertical margins are related to the curative resection of EGC and the prognosis of patients. Thus the accurate prediction of the tumor boundary and its invasive depth before treatment counts for much in planning the most appropriate treatment strategy and promising curative resection. To date, various endoscopic techniques have been identified to play a role in pretreatment evaluation, such as white light endoscopy, chromoendoscopy, narrow band imaging and endoscopic ultrasonography. This article aimed to summarize the diagnostic methods, applications and limitations of these different endoscopic techniques for identifying tumor horizontal and vertical margins in EGC, helping to increase preoperative evaluation of capabilities and to improve the curative resection rate of EGC.