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

Establishing and popularizing a standard pathological diagnostic model of endoscopic submucosal dissection specimens in China

BACKGROUND

Endoscopic submucosal dissection (ESD) is a standardized therapeutic approach for early carcinoma of the digestive tracts. In this regard, the process of histopathological diagnosis requires standardization. However, the uneven development of healthcare in China, especially in eastern and western China, creates challenges for sharing a standardized diagnostic process.

AIM

To optimize the process of ESD specimen sampling, embedding and slide production, and to provide complete and accurate pathological reports.

METHODS

We established a practical process of specimen sampling, created standardized reporting templates, and trained pathologists from neighboring hospitals and those in the western region. A training effectiveness survey was conducted, and the collected data were assessed by the corresponding percentages.

RESULTS

A total of 111 valid feedback forms have been received, among which 58% of the participants obtained photographs during specimen collection, whereas the percentage increased to 79% after training. Only 58% and 62% of the respondents ensured the mucosal tissue strips were flat and their order remained unchanged; after training, these two proportions increased to 95% and 92%, respectively. Approximately half the participants measured the depth of the submucosal infiltration, which significantly increased to 95% after training. The percentage of pathologists who did not evaluate lymphovascular invasion effectively reduced. Only 22% of the participants had fixed clinic-pathological meetings before training, which increased to 49% after training. The number of participants who had a thorough understanding of endoscopic diagnosis also significantly increased.

CONCLUSION

There have been significant improvements in the process of specimen collection, section quality, and pathology reporting in trained hospitals. Therefore, our study provides valuable insights for others facing similar challenges.

Survey of the Actual Practices Used for Endoscopic Removal of Colon Polyps in Korea: A Comparison with the Current Guidelines

Background/Aims

We investigated the clinical practice patterns of Korean endoscopists for the endoscopic resection of colorectal polyps.

Methods

From September to November 2021, an online survey was conducted regarding the preferred resection methods for colorectal polyps, and responses were compared with the international guidelines.

Results

Among 246 respondents, those with <4 years, 4-9 years, and ≥10 years of experience in colonoscopy practices accounted for 25.6%, 34.1%, and 40.2% of endoscopists, respectively. The most preferred resection methods for non-pedunculated lesions were cold forceps polypectomy for ≤3 mm lesions (81.7%), cold snare polypectomy for 4-5 mm (61.0%) and 6-9 mm (43.5%) lesions, hot endoscopic mucosal resection (EMR) for 10-19 mm lesions (72.0%), precut EMR for 20-25 mm lesions (22.0%), and endoscopic submucosal dissection (ESD) for ≥26 mm lesions (29.3%). Hot EMR was favored for pedunculated lesions with a head size <20 mm and stalk size <10 mm (75.6%) and for those with a head size ≥20 mm or stalk size ≥10 mm (58.5%). For suspected superficial and deep submucosal lesions measuring 10-19 mm and ≥20 mm, ESD (26.0% and 38.6%) and surgery (36.6% and 46.3%) were preferred, respectively. The adherence rate to the guidelines ranged from 11.2% to 96.9%, depending on the size, shape, and histology of the lesions.

Conclusions

Adherence to the guidelines for endoscopic resection techniques varied depending on the characteristics of colorectal polyps. Thus, an individualized approach is required to increase adherence to the guidelines.

Comparison of outcomes between surgery and chemoradiotherapy after endoscopic resection for pT1a-MM with lymphovascular invasion or pT1b esophageal squamous cell carcinoma: Japanese multicenter propensity score-matched study

BACKGROUND

Lymphovascular invasion (LVI) or pT1b is noncurative after endoscopic resection (ER) for esophageal squamous cell carcinoma (ESCC), and therefore surgery or chemoradiotherapy (CRT) is recommended. However, there has been debate regarding which treatment has better outcomes and whether individual risks should be considered.

METHODS

This was a multicenter, retrospective study conducted at 65 hospitals in Japan. The inclusion criteria were patients with ESCC who underwent ER between January 2006 and December 2015, with pT1a-muscularis mucosa (MM) with LVI or pT1b, with negative vertical margins, cN0M0, and who underwent surgery or CRT. A 1:1 propensity score-matched analysis was performed between two groups. The primary and secondary end points were overall survival (OS) and relapse-free survival (RFS). OS and RFS were also compared between two subgroups: low risk (pT1a-MM with LVI and pT1b without LVI) and high risk (pT1b with LVI) for metastatic recurrence.

RESULTS

Among 472 patients, 160 patients were selected from each group. The OS and RFS did not differ between surgery and CRT groups (hazard ratio, 0.887; P = .635 and hazard ratio, 1.036; P = .876, respectively). Subgroup analysis showed that CRT had a better prognosis in the low-risk group, and conversely, surgery had a better prognosis in the high-risk group. But these were not significant. The high-risk CRT group had a significant worse prognosis than the low-risk CRT group.

CONCLUSIONS

In patients with noncurative ER for ESCC, surgery and CRT showed no difference in long-term outcomes. Indications for CRT in the high-risk group need further investigation because of poor prognosis.

National Statistics of Endoscopic Submucosal Dissection for Early Gastric Cancer in Korea

PURPOSE

Endoscopic submucosal dissection (ESD) is the standard treatment for early gastric cancer (EGC) with a low risk of lymph node metastasis. In Korea, ESD was included in the National Health Insurance (NHI) coverage in 2011, which was expanded in 2018. In the present study, we investigated the status and trends of ESD for EGC over the past decade since its incorporation into the NHI system.

MATERIALS AND METHODS

We analyzed the data from the National Health Insurance Service (NHIS) database from 2011 to 2021, focusing on patient characteristics, number of ESD procedures, in-hospital length of stay (LOS), and total medical cost (TMC) per admission. In addition, we conducted an interrupted time series analysis to assess the impact of changes in insurance coverage on these variables.

RESULTS

Overall, 95,348 cases of ESD for EGC were identified. A consistent annual increase in ESD procedures was observed, particularly in tertiary care hospitals and among patients aged >60 years. The overall median LOS and TMC were 4 days and 2,123,000 KRW, respectively. The 2018 insurance coverage expansion did not significantly affect the number of ESD procedures or LOS; however, the TMC increased significantly.

CONCLUSIONS

Our study illustrates decade-long trends in the ESD for EGC in Korea. The policy needs to be revised continuously to optimize ESD use and improve resource allocation within healthcare systems.

Identification of maximal tumor size associated with negligible lymph node metastasis for endoscopic submucosal dissection of undifferentiated-type early gastric cancer

BACKGROUND AND AIMS

When treating undifferentiated-type early gastric cancer (UD-EGC) that is limited to the mucosa (clinically T1a), endoscopic submucosal dissection (ESD) can be considered if the tumor is 2 cm or less and is not ulcerated. However, there is insufficient evidence to determine the relationships between tumor size and oncological safety of ESD in UD-EGC.

METHODS

The pathology reports of Korean patients who were diagnosed with UD-EGC (n = 5286) were retrospectively reviewed. The cumulative incidence of lymph node metastasis (LNM) according to tumor size was evaluated in subgroups. The tumor-size cut-off was identified as the upper limit of the 95% confidence interval (CI) of cumulative LNM incidence that did not exceed 1.0%.

RESULTS

We identified 1516 patients with non-ulcerated T1a tumors ≤2 cm in size. Among patients without lymphatic invasion, 1.5% (95% CI 0.91-2.16%) had LNM. In patients with poorly differentiated tubular adenocarcinoma (PD), LNM increased from 0 to 0.74% based on a tumor size of 1.0 cm. Regardless of tumor size, smaller percentages of undifferentiated-type (UD) and poorly cohesive carcinoma (PCC) patients experienced LNM than did those with PD. In non-ulcerated mucosal cancer without lymphatic invasion and tumor size ≤0.9 cm, no LNM was observed in patients with UD (95% CI 0-0.53%), PCC (95% CI 0-0.59%), or PD (95% CI 0-0.86%) histologic type.

CONCLUSION

In patients diagnosed with non-ulcerated T1a UD-EGC, ESD can be performed if the tumor size is 0.9 cm or less, regardless of histologic type.

Predictive factors associated with technical difficulty in colorectal endoscopic submucosal dissection: A Honam Association for the Study of Intestinal Disease (HASID) multicenter study

Colorectal endoscopic submucosal dissection (ESD) is a promising but challenging procedure. It is not widely performed due to its technical difficulty. We aimed to find the predictive factors associated with technical difficulty in colorectal ESD before the procedure. Clinical data from patients who underwent ESD for colorectal tumors in 5 hospitals in Honam province of South Korea between 2015 and 2020 were reviewed retrospectively. Technically difficult colorectal ESD procedure was defined in 3 points. Long procedure time (longer than 60 minutes), occurrence of perforation, and failure of en bloc resection. Factors associated with technically difficult ESD were included as main outcome measure. 1446 patients were identified and their data were analyzed. Median procedure time was 30.0 minutes and median long axis of the tumor was 20.1 mm. Technically difficult procedures including long procedure time were 231 cases (16.0%), perforation occurred in 34 cases (2.3%), and en bloc resection was done in 1292 cases (89.3%). Tumor size larger than 35 mm (odd ratio [OR]: 1.474, P = .047), central depression or ulceration in the lesion (OR: 1.474, P = .013), previous endoscopic mucosal resection (EMR) or polypectomy procedure (OR: 2.428, P = .020) were associated with technically difficult ESD. Descending colon-located tumor (OR: 5.355, P < .001), and use of IT knife (OR: 4.157, P = .003) were associated with perforation. Recognizing factors associated with technically difficult ESD can help in planning the ESD procedure beforehand.

Influence of Procedural Volume on the Outcome of Gastric Endoscopic Submucosal Dissection: A Nationwide Population-Based Study Using Administrative Data

BACKGROUND & AIMS

Endoscopic submucosal dissection (ESD) is a well-established treatment modality for gastric neoplasms. We aimed to investigate the effect of procedural volume on the outcome of ESD for gastric cancer or adenoma.

METHODS

In this population-based cohort study, patients who underwent ESD for gastric cancer or adenoma from November 2011 to December 2017 were identified using the Korean National Health Insurance Service database. Operational definitions to identify the target population and post-procedural complications were created using diagnosis and procedure codes and were validated using hospital medical record data. Outcomes included hemorrhage, perforation, pneumonia, 30-day mortality, a composite outcome comprising all of these adverse outcomes, and additional resection. Hospital volume was categorized into 3 groups based on the results of the threshold analysis: high-, medium-, low-volume centers (HVCs, MVCs, and LVCs, respectively). Inverse probability of treatment weighting analysis was applied to enhance comparability across the volume groups.

RESULTS

There were 94,246 procedures performed in 88,687 patients during the study period. There were 5886 composite events including 4925 hemorrhage, 447 perforation, and 703 pneumonia cases. There were significant differences in ESD-related adverse outcomes among the 3 hospital volume categories, showing that HVCs and MVCs were associated with a lower risk of a composite outcome than LVCs (inverse probability of treatment-weighted odds ratio [OR], 0.651; 95% CI, 0.521-0.814; inverse probability of treatment-weighted OR, 0.641; 95% CI, 0.534-0.769). Similar tendencies were also shown for hemorrhage, perforation, and pneumonia; however, these were not evident for additional resection.

CONCLUSIONS

Procedural volume was closely associated with clinical outcome in patients undergoing ESD for gastric cancer or adenoma.

Harmful effect of repetitive intravenous iodinated contrast media administration on the long-term renal function of patients with early gastric cancer

This retrospective study investigated whether repetitive exposure to intravenous iodinated contrast media (ICM) affects long-term renal function in patients who undergo curative surgery for early gastric cancer (EGC) collected from the Korean Health Insurance and Review Assessment (HIRA) database. Patients diagnosed with gastric cancer between January 2010 and December 2013 underwent regular computed tomography (CT) scans to monitor for extragastric recurrence. Patients who already had chronic kidney disease (CKD) before cancer diagnosis or had undergone chemotherapy or repeated surgery were excluded. A nested case-control study design was chosen to analyze the effect of repetitive ICM exposure to long-term renal function by comparing patients who developed CKD 2 years after cancer diagnosis and patients who did not. Among 59,971 patients collected according to inclusion and exclusion criteria, 1021 were diagnosed with CKD 2 years after cancer diagnosis. Using 1:5 matching after adjusting for age, sex and date of cancer diagnosis, 5097 control patients were matched to 1021 CKD patients. Conditional logistic regression showed that the number of CTs taken using ICM slightly increased the odds of CKD (odds ratio, 1.080; 95% confidence interval (CI): 1.059, 1.100; P < 0.0001). Thus, the administration of ICM might contribute to chronic renal function impairment.

Successful Simultaneous Treatment of Benign Stricture and Colonic Neoplasm Arising from Colonic Interposition after Esophagectomy: A Case Report

Colonic interposition is the main procedure used in esophageal reconstruction. We report a rare case of simultaneous treatment of an anastomotic site stricture and a neoplasm in the interpositioned colon. A 69-year-old female visited our outpatient clinic with symptoms of progressive dysphagia for 1 year. At the age of 30 years, the patient underwent esophagectomy with retrosternal colonic interposition because of severe esophageal burns after chemical ingestion. Upper gastrointestinal endoscopy revealed stricture at the anastomosis site and a 10-mm flat elevated high-grade dysplasia in the interpositioned colon. First, through-the-scope balloon dilatation was performed for strictures. However, stenosis was observed during the second upper gastrointestinal endoscopy session. Therefore, a second session of through-the-scope balloon dilatation was performed, and simultaneously, endoscopic submucosal dissection was also successfully performed. After 2 months of follow-up, stenosis persisted; consequently, balloon dilatation was performed. No recurrence of neoplasm was confirmed endoscopically. Through-the-scope balloon dilatation of the stricture site and simultaneous endoscopic submucosal dissection of the neoplasm in the interpositioned colon were successfully performed.

Effects of prior endoscopic resection on recurrence in patients with T1 colorectal cancer who underwent radical surgery

PURPOSE

Endoscopic resection (ER) is a reliable treatment for early colorectal cancer without lymph node metastasis. We aimed to examine the effects of ER performed prior to T1 colorectal cancer (T1 CRC) surgery by comparing long-term survival after radical surgery with prior ER to that after radical surgery alone.

METHODS

This retrospective study included patients who underwent surgical resection of T1 CRC at the National Cancer Center, Korea, between 2003 and 2017. All eligible patients (n = 543) were divided into primary and secondary surgery groups. To ensure similar characteristics between the groups, 1:1 propensity score matching was used. Baseline characteristics, gross and histological features, along with postoperative recurrence-free survival (RFS) between the two groups were compared. Cox proportional hazard model was used to identify the risk factors affecting recurrence after surgery. Cost analysis was performed to examine the cost-effectiveness of ER and radical surgeries.

RESULTS

No significant differences were observed in 5-year RFS between the two groups in matched data (96.9% vs. 95.5%, p = 0.596) and in the unadjusted model (97.2% vs. 96.8%, p = 0.930). This difference was also similar in subgroup analyses based on node status and high-risk histologic features. ER before surgery did not increase the medical costs of radical surgery.

CONCLUSION

ER prior to radical surgery did not affect the long-term oncologic outcomes of T1 CRC or significantly increased the medical costs. Attempting ER first for suspected T1 CRC would be a good strategy to avoid unnecessary surgery without concerns of worsening cancer-related prognosis.

Therapeutic approach to non-curative resection after endoscopic treatment in early gastric cancer

Background: Endoscopic resection is indicated for early or superficial gastrointestinal neoplasms with a negligible risk of lymph node metastasis. This procedure could preserve the organ while allowing en bloc resection of tumors, irrespective of the size and location of the lesion. Histological evaluation of the resected specimen determines whether curative resection, which implies a favorable long-term outcome, was achieved. If the resected specimen reveals non-curative, additional treatment is necessary as it is strongly associated with recurrence.Current Concepts: Surgical resection is recommended after non-curative resection of gastrointestinal neoplasms. However, rather than surgical resection, additional endoscopic treatment can be recommended if non-curative resection is solely because of the positive involvement at the horizontal resection margin without any other findings compatible with the non-curative resection criteria.Discussion and Conclusion: Adopting precise indications of endoscopic resection is important to reduce the risk of non-curative resection. If curative resection is not achieved after endoscopic resection, additional treatment should be considered to prevent local recurrence as well as lymph node metastasis.

20-Year Trends in Detection Rates of Cardia Cancer via Endoscopic Surveillance in Tianjin, China: A Hospital-Based Study

Background

To analyze the time trends in cardia cancer detection rates using endoscopic surveillance from 1999 to 2019 in a high-volume Chinese hospital.

Methods

In this retrospective, single-center study, data were collected from the Endoscopy Center of the Department of Gastroenterology, Tianjin Medical University General Hospital, from 1999 to 2019. Cases of cardia cancer (n = 1567) were extracted from a database of patients who underwent endoscopy. Clinical and epidemiological characteristics of patients with cardia cancer were analyzed, including sex, age, and proportion of early gastric cancer and degree of tumor differentiation. The joinpoint regression method was used to identify change points in incidence trends. Annual percent change (APC) values, with 95% confidence intervals (CI), were calculated for time periods before and after change points.

Results

Of the 343942 patients who underwent endoscopy during 1999–2009, 1567 (4.6%) were identified with cardia cancer. The overall cardia adenocarcinoma detection rate decreased significantly from 1999 to 2004 (APC = −37.3, 95% CI: -20.9, -6.4), followed by a relatively slower decline rate from 2004 to 2019 (APC = −7.7, 95% CI: -4.4, -7.6). The crude rate of detection of early cardia cancer could not be determined by joinpoint analysis. Rates of detection reduced significantly in patients aged 60–69 and 70-79 years (APC = −8.3, 95% CI: -9.8, -6.8 and APC = −7.3, 95% CI: -8.8, -5.8, respectively). The detection rate in males decreased rapidly from 1999 to 2004 (APC = −35.9, 95% CI: -18.2, 5.6, P < 0.05), while the decline rate was relatively slow from 2005 to 2019 (APC = −6.9, 95% CI: -3.4, -6.1, P < 0.05). Among females, the detection rates also decreased from 1999 to 2004 (APC = −21.2, 95% CI: -28.1, -13.7), but remained stable from 2007 to 2019 (APC = −3.8, 95% CI: -7.9, -0.5). Detection of poorly differentiated cardia cancer also declined from 2009 to 2019 (APC = −12.8, 95% CI: -15.3, -10.0).

Conclusions

The detection rate of cardia cancer among gastric cancers has been stable from 2008 to 2019. The trend of detection rate of early cardia cancer showed no significant statistical meaning; hence, it remains necessary to carefully observe the cardia area during endoscopy examination.

[Treatment of Superficial Esophageal Cancer: An Update]

Superficial esophageal squamous cell carcinoma (SESCC) is an esophageal squamous cell carcinoma confined to the mucosa or superficial submucosa. Recent Korean Guidelines recommend an endoscopic resection as the first-line treatment for SESCC without a distant or lymph node metastasis (LNM) after excluding those with an obvious submucosal invasion. Before endoscopic treatment of SESCC, Lugol chromoendoscopy or image-enhanced endoscopy is recommended to define the extent of the lesion, and endoscopic ultrasound is recommended to determine the T stage. The tumor size, macroscopic type of tumor, pathologic differentiation, depth of tumor, and lymphovascular invasion (LVI) are risk factors of LNM in SESCC. No additional treatment is necessary after an en bloc complete resection of SESCC invading no more than the lamina propria without LVI. Although the risk of LNM in a SESCC invading into muscularis mucosa without LVI is low, a close follow-up is recommended without additional treatment. On the other hand, additional treatment is recommended in the case of a tumor with submucosal invasion or an LVI positive or positive vertical resection margin. Adjuvant therapy includes esophagectomy or chemoradiotherapy (CRT), but it is unclear which treatment is better. The 5-year overall survival rates were reportedly 90-100% for esophagectomy and 75-85% for CRT. Nevertheless, patients with high-risk features including poorly differentiated histology, LVI positive, perineural invasion positive, T1b-SM2/T1b-SM3 cancer, and vertical resection margin positive need to be treated with an additional esophagectomy. Elderly patients, those with a physical condition and co-morbidities, and those with LNM or cancer-specific mortality require additional treatment after a non-curative endoscopic resection of SESCC.

Clinical feasibility and oncologic safety of primary endoscopic submucosal dissection for clinical submucosal invasive early gastric cancer

PURPOSE

This study aimed to evaluate the clinical feasibility and oncologic safety of primary endoscopic submucosal dissection for cT1bN0M0 gastric cancer by identifying patients who had undergone curative resection after endoscopic submucosal dissection and patients who had undergone primary surgery but could be treated with endoscopic submucosal dissection.

METHODS

A single-center retrospective cohort study was conducted on patients with cT1bN0M0 gastric cancer (size: ≤ 30 mm) and differentiated histology from January 2007 to May 2017. Submucosal invasion was evaluated using conventional endoscopy and endoscopic ultrasonography. Patients were divided into the primary endoscopic submucosal dissection and primary surgery groups according to initial treatment.

RESULTS

Curative resection rate was 65.0% (91/140) in the primary endoscopic submucosal dissection group. Of patients in the primary surgery group, 49.1% (82/167) were considered eligible for endoscopic submucosal dissection. No differences in en bloc resection rate were observed between pT1a and pT1b gastric cancers after endoscopic submucosal dissection (97.8 vs. 97.9%). However, the negative horizontal margin rate was higher in pT1a gastric cancer than pT1b gastric cancer (98.9 vs. 91.3%). There was no difference in overall survival among the curative treatment groups (log rank P = 0.310).

CONCLUSION

In this study, 173 (56.4%) out of 307 patients with cT1bN0M0 gastric cancer could avoid unnecessary surgery if primary endoscopic submucosal dissection was used. Based on these findings, it is necessary to add an appropriate indication for endoscopic submucosal dissection in patients with cT1b gastric cancer. Further management could be determined based on pathologic findings after primary endoscopic submucosal dissection.