Lymph node involvement in gastric adenocarcinoma

Background Endoscopic management of early gastric cancer is limited by the risk of lymph node metastasis. We aimed to examine the incidence and predictors of nodal metastasis in early gastric adenocarcinoma in a large national US cohort. Methods Cases were abstracted from the National Cancer Database from 2004 to 2016. The incidence and predictors of lymph node involvement for patients with Tis, T1a, and T1b tumors were examined. Results A total of 202,216 cases of gastric adenocarcinoma were identified in the NCDB. Cases with unknown patient or tumor characteristics, presence of other cancers, and prior neoadjuvant chemotherapy or radiotherapy were excluded. 1839 cases of Tis, T1a, and T1b tumors were identified. Lymph node metastases were present in 18.1% of patients. Lymphovascular invasion (LVI), high-grade histology, stage T1b, and larger size (> 3 cm) were independently associated with an increased risk of nodal metastasis on multivariate analysis (P