Endoscopic surveillance strategy after endoscopic resection for early gastric cancer

Clinical outcomes of metachronous recurrence of gastric epithelial neoplasia based on Helicobacter pylori infection status and microsatellite stability

BACKGROUND/AIMS

Helicobacter pylori eradication may prevent the recurrence of gastric epithelial neoplasia after endoscopic treatment. However, H. pylori eradication therapy is unlikely to prevent gastric cancer. This study determined the longterm results and clinical outcomes of patients with gastric epithelial neoplasia based on H. pylori infection status and microsatellite stability (MSS).

METHODS

Patients diagnosed with gastric epithelial neoplasia who underwent an endoscopic mucosal resection or submucosal dissection between 2004 and 2010 were included in this retrospective study. During the follow-up period (range, 4 to 14 years), disease recurrence was monitored, and tissue examinations were conducted for seven sets of microsatellite loci initially linked to the tumour suppressor gene locus. When H. pylori infection was identified, patients underwent eradication therapy.

RESULTS

The patients (n = 120) were divided into three groups: H. pylori-negative with MSS, H. pylori-positive with MSS, and microsatellite instability (MSI). After H. pylori eradication, the rate of metachronous recurrence was significantly different in the MSI (28.2%) and MSS groups (3.7%, p < 0.01). The mean duration of recurrence was 77 months (range, 24 to 139) in the MSI group. There was no recurrence after eradication therapy in patients who were positive for H. pylori in the MSS group.

CONCLUSION

H. pylori eradication could help prevent gastric cancer recurrence in patients with stable microsatellite loci. Careful, long-term monitoring is required in patients with unstable microsatellite loci.

Incidence and treatment outcomes of metachronous gastric cancer occurring after curative endoscopic submucosal dissection of undifferentiated-type early gastric cancer: Japan Clinical Oncology Group study-post hoc analysis of JCOG1009/1010

BACKGROUND AND AIMS

A drawback of endoscopic submucosal dissection (ESD) for early gastric cancer (EGC) is the development of metachronous gastric cancer (MGC). While MGC after ESD for differentiated-type (D-) EGC was well understood, little is known about MGC occurring after ESD for undifferentiated-type (UD-) EGC, because ESD had not been indicated. We evaluated the incidence and treatment outcomes of MGC after ESD of UD-EGC.

METHODS

This study is a post hoc analysis of JCOG1009/1010, a multicenter trial to evaluate the efficacy and safety of ESD for UD-EGC. The patients who underwent curative ESD of index solitary UD-EGC were analyzed. Surveillance endoscopy was performed biannually for the first 3 years and thereafter annually. We assessed the time to MGC occurrence after ESD, lesion characteristics, and treatment outcomes of MGC. Time to MGC occurrence was estimated by cumulative incidence function, with death and total gastrectomy as competing risks.

RESULTS

A total of 198 patients were included in this study. During a median follow-up period of 5.8 years, 4 patients (2%) developed MGC. Median time to MGC occurrence was 4.5 years (range: 3.1-5.4). Five-year cumulative incidence of MGC was 1.0% (95% CI: 0.2-3.3%). Two MGCs were histologically D-EGC, and the remaining two were UD-EGC. The median tumor size of MGCs was 1.0 cm (range: 0.7-1.7), and the depth of invasion (M/SM1/SM2) was 2/1/1, respectively. Three patients achieved curative resection with repeated ESD.

CONCLUSIONS

MGC does not occur commonly after curative ESD of UD-EGC, and repeated ESD could contribute to stomach preservation.

The incidences of metachronous multiple gastric cancer after various types of gastrectomy: analysis of data from a nationwide Japanese survey

BACKGROUND

The incidence of metachronous multiple gastric cancer (MMGC) after gastrectomy remains unclear. This study evaluated the incidences of MMGC according to specific gastrectomy types, including pylorus-preserving gastrectomy (PPG), proximal gastrectomy (PG), and function-preserving gastrectomy (FPG), which was categorized as segmental gastrectomy and local resection.

METHODS

We conducted a questionnaire survey of the Japanese Society for Gastro-Surgical Pathophysiology members, who were asked to report their institutional numbers of radical gastrectomy cases for cancer between 2003 and 2012. The cases were categorized according to whether the remnant stomach's status was followed for > 5 years, confirmation of MMGC, time to diagnosis, and treatment for MMGC. We calculated the "precise incidence" of MMGC by dividing the number of MMGC cases by the number of cases in which the status of remnant stomach was followed up for > 5 years.

RESULTS

The responses identified 33,731 cases of gastrectomy. The precise incidences of MMGC were 2.35% after distal gastrectomy (DG), 3.01% after PPG, 6.28% after PG (p < 0.001), and 8.21% after FPG (p < 0.001). A substantial proportion of MMGCs (36.4%) was found at 5 years after the initial surgery. The rates of MMGC treatment using endoscopic submucosal dissection were 31% after DG, 28.6% after PPG, 50.8% after PG (p < 0.001), and 67.9% after FPG (p < 0.001).

CONCLUSIONS

The incidence of MMGC was 2.4% after DG, and higher incidences were observed for larger stomach remnants. However, the proportion of cases in which MMGC could be treated using endoscopic submucosal dissection was significantly higher after PG and FPG than after DG.

Synergistic Effect of Lymphatic Invasion and Venous Invasion on the Risk of Lymph Node Metastasis in Patients with Non-Curative Endoscopic Resection of Early Gastric Cancer

BACKGROUND

Although additive radical surgery is recommended for patients with non-curative endoscopic resection for early gastric cancer (EGC), lymph node (LN) metastasis or remnant tumor is detected in only about 10% of patients. Therefore, we aimed to identify patients who required surgery by identifying significant risk factors for LN metastasis and evaluate long-term outcomes in patients with non-curative endoscopic resection.

METHODS

We retrospectively analyzed the database of Seoul National University Hospital to identify patients who underwent endoscopic resection for EGC from June 2005 to December 2016.

RESULTS

Three hundred and twenty-nine patients did not meet the criteria for curative resection after endoscopic resection. Among them, 140 patients underwent additional surgery and 171 patients refused surgery and regularly received follow-up. In the surgery group, LN metastasis was found in 12.1% of patients. Logistic regression analysis revealed that the rate of LN metastasis was significantly higher in patients with lymphatic invasion (LI) (odds ratio [OR] 5.84, p = 0.014) and venous invasion (VI) (OR 5.66, p = 0.006). We analyzed LN metastasis based on LI and VI in the surgical group. LN metastasis was significantly increased in the positive LI and VI groups compared with the negative LI and VI groups (OR 68.32; 95% confidence interval, 4.74-984.82; p = 0.002).

CONCLUSIONS

Both LI and VI were significant predictors of LN metastasis. The risk of LN metastasis was augmented when both LI and VI were positive. Therefore, LI and VI should be evaluated separately in patients with non-curative endoscopic resection. Additive surgery should be recommended for patients with LI and/or VI.

Increased incidence of metachronous gastric neoplasm after endoscopic resection in patients with synchronous gastric neoplasm

Background

Recurrence risk is a major concern after endoscopic resection (ER) of gastric neoplasms. This study was to compare metachronous risk in patients with and without synchronous neoplasms after complete ER.

Methods

After ER for gastric neoplasms, patients were divided into those with and without synchronous neoplasm. The metachronous risk of gastric neoplasms was compared between the two groups.

Results

After ER of 678 cancers and 891 adenomas, synchronous neoplasm was found in 11.8% of cancers and 11.4% of adenomas. In the multiple (n = 182) and the single group (n = 1387), metachronous neoplasms occurred in 18.1 and 8.6%, respectively (HR 2.40; 95% CI, 1.62–3.34). When the pathology of the recurred lesion was limited to cancer, metachronous risk was also significantly higher in the multiple than in the single group (HR, 2.2; 95% CI, 1.17–3.85). In the recurred pathology of the multiple group, cancer development was frequently observed in patients with cancer compared to those with only adenomas in the synchronous lesion (67.0% vs. 13.0%, respectively; P = 0.023).

Conclusions

This study demonstrated that metachronous risk was significantly higher in patients with synchronous gastric neoplasms after ER. Therefore, meticulous examination is important in patients with synchronous neoplasm.

Assessment of Endoscopic Gastric Atrophy according to the Kimura-Takemoto Classification and Its Potential Application in Daily Practice

The assessment of endoscopic gastric atrophy (EGA) according to the Kimura-Takemoto classification has been reported to correlate well with histological assessment. Although agreement among beginner endoscopists was less than that among experienced endoscopists, it has been shown that agreement level could markedly improve and remained stable after proper training. Several cohort studies have consistently shown that the severity of EGA at baseline is significantly associated with the presence of advanced precancerous gastric lesions and gastric cancer, as well as the development of gastric cancer in future. Patients with moderate-to-severe EGA still have high risk of gastric cancer even after successful Helicobacter pylori eradication and should be candidates for gastric cancer surveillance. The assessment of EGA, therefore, could be used as a preliminary tool to identify individuals at high risk for gastric cancer. In this paper, we review the agreement on mucosal atrophy assessment between the Kimura-Takemoto classification and histology as well as the potential application of this endoscopic classification to identify precancerous gastric lesions and gastric cancer in daily practice.

Characteristics of overlooked synchronous gastric epithelial neoplasia after endoscopic submucosal dissection

Since endoscopic submucosal dissection (ESD) has been accepted as the treatment of choice for early gastric cancer (EGC) without risk of lymph node metastasis, synchronous gastric epithelial neoplasia is no longer rare in the clinical practice. Knowledge about the characteristics associated with synchronous gastric epithelial neoplasia is of great importance to prevent delayed diagnosis.Between November 2008 and December 2014, a retrospective study was conducted in a single tertiary referral hospital. Consecutive patients who underwent ESD due to EGC or high-grade dysplasia were analyzed to evaluate the incidence of synchronous gastric epithelial neoplasia and the factors associated with synchronous and overlooked synchronous lesions.A total of 488 patients were analyzed in this study. Synchronous lesions were found in 59 patients (12.1%) during the mean 37.7 months of follow-up. Among 77 synchronous lesions, 25 lesions (32.4%) were overlooked at the time of initial ESD. Age of ≥ 65 years, moderate to severe endoscopic atrophic gastritis, and elevated morphology of primary lesions were associated with synchronous gastric epithelial neoplasia. An important factor associated with overlooked lesions is the non-elevated morphology of lesions.Careful endoscopic examination of the whole stomach is necessary in patients who are older and who have moderate to severe atrophic gastritis and elevated morphology of lesions to prevent delayed diagnosis of synchronous gastric epithelial neoplasia, especially non-elevated lesions.

Novel risk stratification for metachronous recurrence after curative endoscopic submucosal dissection for early gastric cancer

BACKGROUND AND AIMS

This study stratified the risk of developing metachronous gastric cancer (MGC) after curative endoscopic submucosal dissection (ESD) of early gastric cancer (EGC) to enable customization of endoscopic surveillance for MGC.

METHODS

A total of 1115 patients who underwent curative ESD based on the expanded criteria for differentiated EGC from 2005 to 2014 at a single tertiary hospital were enrolled in this retrospective cohort study. They were followed up with annual endoscopy for a median of 50.1 months. Helicobacter pylori and histologic intestinal metaplasia (IM) were evaluated. The Kaplan-Meier method and Cox regression analysis were used for risk stratification.

RESULTS

Three risk groups were identified: group 1 comprised patients with a synchronous neoplasm; group 2 comprised male patients with corpus IM; and group 3 comprised male patients without corpus IM or female patients. The 5- and 7-year cumulative risks (95% confidence interval [CI]) for metachronous recurrence were 15.1% (95% CI, 7.7-22.5) and 26.1% (95% CI, 14.9-37.3), respectively, in group 1; 5.6% (95% CI, 3.1-8.1) and 9.3% (95% CI, 5.4-13.2), respectively, in group 2; and 3.8% (95% CI, 1.6-6.0) and 4.9% (95% CI, 2.4-7.4), respectively, in group 3 (P < .001 by log-rank test). The incidence of MGCs increased constantly even after 5 years in groups 1 and 2 but not in group 3. There was not enough evidence to show an association between H pylori eradication and metachronous recurrence in the data.

CONCLUSIONS

Meticulous annual endoscopic surveillance for MGC for more than 5 years is recommended for patients with synchronous neoplasm. Endoscopic surveillance may also be extended beyond 5 years in male patients with corpus IM.

Improved glycemic control with proximal intestinal bypass and weight loss following gastrectomy in non-obese diabetic gastric cancer patients

PURPOSE

The aim of this study was to assess whether gastrectomy influences glycemic control in non-obese diabetic gastric cancer patients and to identify factors related to glucose metabolism after gastrectomy.

MATERIALS AND METHODS

We retrospectively analyzed changes in glucose metabolism in 238 non-obese (body mass index < 30 kg/m2) patients with type II diabetes who underwent distal gastrectomy with either gastroduodenostomy (n = 91) or gastrojejunostomy (n = 147) for stage I gastric cancer. We collected demographics, diabetes-related features, surgery-related features, and changes in glucose metabolism during follow-up. The effect of surgery on the course of diabetes was evaluated at different time points according to fasting blood glucose levels and use of diabetes-related medication.

RESULTS

Preoperatively, the mean body mass index was 24.3 ± 2.3. Weight, body mass index and fasting blood glucose of all patients were significantly lower compared to preoperative levels at all time points. Weight loss after 6 months and the percentage of patients whose weight loss ratio was higher than 10% after one year were greater in the gastrojejunostomy group than the gastroduodenostomy group. Overall, 88 (37%) patients showed improvement in their diabetes course at one month after surgery; 152 (64%) showed improvement after 2 years. Duration of diabetes, weight loss, and reconstruction type were associated with improvement in diabetes at different time points. At 6 months and thereafter, the percentage of patients with an improved diabetes course was highest in the gastrojejunostomy plus higher than 10% weight loss group.

CONCLUSIONS

Although weight loss may be associated with adverse effects of gastrectomy, postoperative weight loss in an acceptable range is a useful measure of the better glycemic control for the group of diabetic patients. Selecting gastrojejunostomy during gastrectomy and inducing acceptable weight loss after gastrectomy could be beneficial to the non-obese diabetic gastric cancer patients for improved glycemic control.

Metachronous Gastric Cancer Following Curative Endoscopic Resection of Early Gastric Cancer

This review article summarizes knowledge about metachronous gastric cancer (MGC) occurring after curative endoscopic resection (ER) of early gastric cancer (EGC), treatment outcomes of patients who developed MGC, and efficacy of Helicobacter pylori eradication to prevent MGC. The incidence of MGC following curative ER increases over time and is higher than in patients undergoing gastrectomy. Increasing age and multifocal EGC are independent risk factors for developing MGC. An MGC following curative ER is usually a small (<20 mm) and differentiated intramucosal cancer. Most MGC lesions are found at an early stage on semiannual or annual surveillance endoscopy and are successfully treated by further ER, with excellent long-term outcomes. Eradication of H. pylori may reduce the risk of MGC following ER of EGC, but further prospective studies with long-term outcomes are required. Surveillance endoscopy following gastric ER should be continued indefinitely, due to the risk of MGC even after successful H. pylori eradication. Risk stratification and tailored endoscopic surveillance schedules need to be developed.

Surveillance for Gastric Cancer

This article discusses the current National Comprehensive Cancer Network guidelines and other available Western and Eastern guidelines for the surveillance of gastric cancer following surgical resection. It reviews the literature assessing the utility of intensive surveillance strategies for gastric cancer, which fails to show an improvement in survival. The unique issues relating to follow-up of early gastric cancer and after endoscopic resection of early gastric cancer are discussed. This article also reviews the available modalities for follow-up. In addition, it briefly discusses the advancements in treatment of recurrent and metastatic disease and the implications for gastric cancer survival and surveillance strategies.

Therapeutic outcomes of endoscopic submucosal dissection for early gastric cancer: single-center study

OBJECTIVES

Endoscopic submucosal dissection (ESD) has been widely accepted for selected patients with early gastric cancer (EGC). The aim of this study was to assess the therapeutic outcomes after ESD according to the pathological extent.

PATIENTS AND METHODS

From January 2005 to December 2014, a total of 599 patients with 611 lesions were enrolled in this study. The tumors were categorized according to pathological results on the basis of absolute criteria (AC), expanded criteria (EC), EC with undifferentiated histology [(EC-U), mucosal cancer, ulcer (-), ≤20 mm], or beyond EC (BEC). The therapeutic outcomes among the four groups were analyzed retrospectively.

RESULTS

The number of patients in the AC, EC, EC-U, and BEC groups was 447, 91, 19, and 54. The complete resection rates of EGC were 97.8, 84.6, 94.4, and 45.5% (P=0.001) and en bloc resection rates in the AC, EC, EC-U, and BEC groups were 99.1, 98.9, 100, and 98.1% (P=0.833), respectively. The 5-year disease-free survival rate in the AC, EC, EC-U, and BEC groups was 90.6, 88.7, 75.0, and 83.3% (P=0.394). In multivariate analysis, undifferentiated histology (P=0.001) and tumor size (>30 mm, P=0.017) were risk factors related to local recurrence.

CONCLUSION

The efficacy of ESD for EGCs in EC is almost equal to that in AC when complete resection was achieved. However, the indication for ESD should be decided conservatively because the complete resection rate of EGC in the EC group was significantly lower than that in the AC group. Undifferentiated histology and tumor size over 30 mm were risk factors related to local recurrence.

Optimal management for patients not meeting the inclusion criteria after endoscopic submucosal dissection for gastric cancer

BACKGROUND

The necessity of additional gastrectomy for patients not meeting the inclusion criteria after endoscopic submu cosal dissection (ESD) is controversial. The aim of this study was to elucidate the risk factors for lymph node metastasis (LNM) and residual cancer (RC) in patients not meeting the inclusion criteria after ESD and to determine additional treatment strategies.

METHODS

Of 1443 gastric cancer patients who underwent ESD between 2004 and 2013, 167 patients diagnosed as having a lesion not meeting the inclusion criteria after ESD were retrospectively analyzed. Of the 167 cases, 100 cases underwent additional gastrectomy, and 67 cases were observed without surgery.

RESULTS

Overall, 9.0 % (9/100) and 9.0 % (9/100) of patients not meeting the inclusion criteria after ESD presented with LNM and RC, respectively, but neither was observed in 83 patients (83.0 %). Multivariate analysis revealed that lymphovascular involvement (LVI) (OR 38.38; 95 % CI 1.94-761.43, p = 0.017) and undifferentiated type (OR 45.58; 95 % CI 2.88-720.94, p = 0.007) were independent risk factors for LNM, and positive horizontal margin was an independent risk factor for RC (OR 9.48; 95 % CI 1.72-52.13, p = 0.010). In differentiated types without LVI, no cases had LNM (0/38) in the additional gastrectomy group, and there was no lymph node or distant recurrence (0/39) in the observation group.

CONCLUSIONS

Additional treatment is necessary for patients with LVI, undifferentiated type, and positive horizontal margin. Careful follow-up may be acceptable for patients with the differentiated type without LVI, especially for the elderly or patients with severe comorbidities.

Endoscopic submucosal dissection in early gastric cancer in elderly patients and comorbid conditions

The prognosis of early gastric cancer (EGC) is good if there is no concomitant lymph node metastasis. Therefore, the early detection of EGC is important to improve the prognosis of patients with gastric cancer. In Japan, 40% to 50% of all gastric cancers are EGC, and endoscopic submucosal dissection (ESD) is widely accepted as a local treatment for these lesions, particularly for large lesions that at one time were an indication for gastrectomy because of the difficulty of en-bloc resection. Consequently, this procedure can preserve the entire stomach and the patient's postoperative quality of life. ESD has become a general technique with improved procedures and devices, and has become the preferred treatment for EGC rather than gastrectomy. Therefore, ESD may demonstrate many advantages in patients who have several comorbidities, particularly elderly population, patients taking antithrombotic agents, or patients with chronic kidney disease, or liver cirrhosis. However, it is not yet clear whether patients with both EGC and comorbidities are feasible candidates for ESD and whether they would consequently be able to achieve a survival benefit after ESD. In this review, we discuss the clinical problems of ESD in patients with EGC and those comorbid conditions.

Progress in research of gastric intraepithelial neoplasia

Gastric carcinoma is one of the most common malignant tumors in the world, and the accurate diagnosis of precancerous lesions plays an important role in gastric cancer prevention. Intraepithelial neoplasia is a form of precancerous lesion of gastric cancer, and many efforts have been done to explore the relationship between gastric cancer and dysplasia. Recently, there has been much progress in the research of intraepithelial neoplasia, including genetic changes at the molecular level, the eradication of Helicobacter pylori (H. pylori), regular follow-up and endoscopic therapy. All of these will play an important role in clinical management of this condition. However, the etiological mechanism, influencing factors and malignant transformation of GIN are still unclear. Hence, further multi-center and long-term prospective studies are needed to solve these problems.