Objective To investigate the influencing of inferior mediastinum and esophageal hiatus lymph node metastasis by submucosal different venous divisions of esophagogastric junction (EGJ) invaded in Siewert type Ⅱ adenocarcinoma of esophagogastric junction (AEG).

Methods The retrospective case-control study was conducted. The clinicopathological data of 547 patients with Siewert type Ⅱ AEG who were admitted to Shanxi Cancer Hospital from January 2018 to December 2021 were collected. There were 461 males and 86 females, aged 61 (range, 33‒75)years. Observa-tion indicators: (1) lymph node metastasis rate in different groups; (2) influencing factors of inferior mediastinum lymph node metastasis in Siewert type Ⅱ AEG; (3) influencing factors of esophageal hiatus lymph node metastasis in Siewert type Ⅱ AEG. Measurement data with normal distribution were represented as Mean±SD, and comparison between groups was conducted using the t test. Measurement data with skewed distribution were represented as M(range) or M(Q₁,Q₃), and com-parison between groups was conducted using the Mann‑Whitney U test. Count data were described as percentages or absolute numbers, and comparison between groups was conducted using the chi‑square test. The univariate analysis was conducted using the corresponding statistical methods based on data type. The Logistic regression model was used for multivariate analysis.

Results (1) Lymph node metastasis rate in different groups. The lymph node metastasis rate in No. 1, 2, 3, 4sa, 4sb, 7, 8a, 9, 11,20, 108, 110 of the 547 patients was 17.37%(95/547), 6.76%(37/547), 46.44%(254/547), 1.65%(9/547), 1.10%(6/547), 23.22%(127/547), 4.39%(24/547), 3.11%(17/547), 3.47%(19/547), 3.66%(20/547), 0.55%(3/547), 4.20%(23/547), respectively. Of the 547 patients, there were 456 cases with proximal of AEG invading submucosal palisade venous of EGJ including 4 cases with inferior mediastinum lymph node metastasis and no case with media mediastinum or up media-stinum lymph node metastasis. There were 91 cases with proximal of AEG invading submucosal perforator venous of EGJ including 18 cases with inferior mediastinum lymph node metastasis, 3 cases with media mediastinum lymph node metastasis and no case with up mediastinum lymph node metastasis. (2) Influencing factors of inferior mediastinum lymph node metastasis in Siewert type Ⅱ AEG. Results of multivariate analysis showed that age, tumor invading submucosal perforator venous of EGJ and histological classification were independent influencing factors for inferior media-stinum lymph node metastasis of Siewert type Ⅱ AEG (odds ratio=0.93, 23.33, 0.31, 95% confidence interval as 0.87‒0.99, 4.18‒130.28, 0.12‒0.78, P<0.05). (3) Influencing factors of esophageal hiatus lymph node metastasis in Siewert type Ⅱ AEG. Tumor invading submucosal perforator venous of EGJ was an independent influencing factor for esophageal hiatus lymph node metastasis of Siewert type Ⅱ AEG (odds ratio=14.95, 95% confidence interval as 2.46‒90.76, P<0.05).

Conclusion Age, tumor invading submucosal perforator venous of EGJ and histological classification are independent influencing factors for inferior mediastinum lymph node metastasis of Siewert type Ⅱ AEG, and tumor invading submucosal perforator venous of EGJ is an independent influencing factor for esophageal hiatus lymph node metastasis.