A 6-year nationwide population-based study on the current status of gastric endoscopic resection in Korea using administrative data

Re-evaluation of the role of endoscopic submucosal dissection in the treatment of early gastric cancer based on additional gastrectomy results

Endoscopic submucosal dissection (ESD) plays a pivotal role in treating early gastric cancer (EGC). Some patients require additional gastrectomy because of non-curative ESD. This study aimed to analyze the clinical factors associated with non-curative ESD and to re-evaluate the role of ESD according to its indication criteria. Altogether, 134 patients who had undergone additional gastrectomy with lymphadenectomy for non-curative ESD based on the pathological results of ESD specimens were included. Their data including pre-ESD diagnosis, reasons for requesting additional gastrectomy, and surgical outcomes were analyzed retrospectively. Of the 134 patients with EGC in the final pathology of ESD specimens, 56 underwent staging ESD for a diagnostic approach, of whom 28 were diagnosed with atypical glands and 28 with high-grade dysplasia (HGD) prior to ESD. The remaining 78 patients of the 134 were identified to have EGC and received ESD for therapy. Based on the pathological results of ESD specimens, additional gastrectomy was commissioned with non-curative ESD because of one or more causes such as deep submucosal invasion, lymphatic invasion, positive vertical margin, undifferentiated histology, positive lateral margin, and venous invasion. Regarding surgical specimens, 13 patients had lymph node metastasis (LNM) and 9 had local residual tumor; one of them had both LNM and a local residual tumor. In patients with atypical glands, 4 had LNM and 3 had a local residual tumor; one of them had both LNM and a local residual tumor, and then died of multiple organ metastasis. In patients with HGD, 4 had LNM and 1 had a local residual tumor. Additionally, 4 patients who were absolutely indicated for ESD had LNM, of whom 2 had atypical glands, and the other 2 had HGD. Similarly, in 6 patients with a local residual tumor absolutely indicated for ESD, 2 had atypical glands and 1 had HGD. Positive vertical margin, lymphatic invasion, and deep submucosal invasion were identified as independent risk factors for LNM. ESD may play diagnostic and therapeutic roles in determining the optimal treatment of EGC when the diagnosis is equivocal or insufficient in endoscopic assessments for gastric cancer screening.

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.

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.