Metachronous Gastric Cancer: Another Hurdle for Successful Endoscopic Treatment for Early Gastric Cancer?

Predictive biomarkers for metachronous gastric cancer development after endoscopic resection of early gastric cancer

OBJECTIVES

We aimed to identify predictive markers for metachronous gastric cancer (MGC) in early gastric cancer (EGC) patients curatively treated with endoscopic submucosal dissection (ESD).

MATERIALS AND METHODS

From EGC patients who underwent ESD, bulk RNA sequencing was performed on non-cancerous gastric mucosa samples at the time of initial EGC diagnosis. This included 23 patients who developed MGC, and 23 control patients without additional gastric neoplasms for over 3 years (1:1 matched by age, sex, and Helicobacter pylori infection state). Candidate differentially-expressed genes were identified, from which biomarkers were selected using real-time quantitative polymerase chain reaction and cell viability assays using gastric cell lines. An independent validation cohort of 55 MGC patients and 125 controls was used for marker validation. We also examined the severity of gastric intestinal metaplasia, a known premalignant condition, at initial diagnosis.

RESULTS

From the discovery cohort, 86 candidate genes were identified of which KDF1 and CDK1 were selected as markers for MGC, which were confirmed in the validation cohort. CERB5 and AKT2 isoform were identified as markers related to intestinal metaplasia and were also highly expressed in MGC patients compared to controls (p < 0.01). Combining these markers with clinical data (age, sex, H. pylori and severity of intestinal metaplasia) yielded an area under the curve (AUC) of 0.91 (95% CI, 0.85-0.97) for MGC prediction.

CONCLUSION

Assessing biomarkers in non-cancerous gastric mucosa may be a useful method for predicting MGC in EGC patients and identifying patients with a higher risk of developing MGC, who can benefit from rigorous surveillance.

Outcomes of Endoscopic Resection for Early Gastric Cancer in Very Elderly Patients: A Nationwide Population-Based Study

Background/Aims

Few studies have investigated the long-term outcomes of endoscopic resection for early gastric cancer (EGC) in very elderly patients. The aim of this study was to determine the appropriate treatment strategy and identify the risk factors for mortality in these patients.

Methods

Patients with EGC who underwent endoscopic resection from 2006 to 2017 were identified using National Health Insurance Data and divided into three age groups: very elderly (≥85 years), elderly (65 to 84 years), and non-elderly (≤64 years). Their long- and short-term outcomes were compared in the three age groups, and the survival in the groups was compared with that in the control group, matched by age and sex. We also evaluated the risk factors for long- and short-term outcomes.

Results

A total of 8,426 patients were included in our study: 118 very elderly, 4,583 elderly, and 3,725 non-elderly. The overall survival and cancer-specific survival rates were significantly lower in the very elderly group than in the elderly and the non-elderly groups. Congestive heart failure was negatively associated with cancer-specific survival. A significantly decreased risk for mortality was observed in all groups (p<0.001). The very elderly group had significantly higher readmission and mortality rates within 3 months of endoscopic resection than the non-elderly and elderly groups. Furthermore, the cerebrovascular disease was associated with mortality within 3 months after endoscopic resection.

Conclusions

Endoscopic resection for EGC can be helpful for very elderly patients, and it may play a role in achieving overall survival comparable to that of the control group.