Clinical Outcomes of Endoscopic Submucosal Dissection for Early Gastric Cancer Patients With Concurrent Advanced Malignancies With Expected Poor Prognosis.

Aims: Despite improved outcomes for malignant tumors, evidence regarding the management of patients with multiple malignancies remains limited. We aimed to evaluate the clinical outcomes and prognosis of patients undergoing endoscopic submucosal dissection (ESD) for early gastric cancer (EGC) complicated by advanced malignancies in other organs with a poor prognosis. Methods and Results: We retrospectively reviewed 3703 gastric cancer patients who underwent ESD at our hospital (2005-2022), focusing on those with advanced extra-gastric malignancies with a 5-year survival rate of < 50%. ESD was performed for local tumor control based on patient preference when feasible, including lesions meeting standard, expanded, or relative indications where curative resection was unachievable. Clinicopathological characteristics and outcomes were analyzed. Twenty-six patients met the inclusion criteria. En bloc resection was achieved in all cases (100%), with curative and non-curative resection in 16 (62%) and 10 (38%) cases, respectively. None of the 10 patients with non-curative resection exhibited lymphovascular invasion or GC recurrence. Complications included delayed bleeding, perforation, and pneumonia, each in one patient (4%), all leading to disseminated intravascular coagulation (DIC) and death within 30 days post-ESD. Notably, no complications were reported after 2010. Eleven patients died from advanced malignant tumors, with no GC recurrences observed during follow-up in surviving patients. Conclusions: Recently, no severe complications have been observed with ESD. Although ESD for local control in EGC with concurrent advanced extra-gastric malignancies may be acceptable, the risk of severe complications, including DIC, remains. Therefore, careful patient selection and thorough informed consent are essential.