ABSTRACT
The proportion of adenocarcinoma of the esophagogastric junction (AEG) in gastric cancer is gradually increasing. Due to the unique anatomical structure and biological characteristics of the tumor at this site, AEG has a certain degree of complexity in many aspects of diagnosis and treatment, which brings difficulties to the operation method, the selection of the resection range, the lymph node dissection and the treatment decision-making. Therefore, AEG has always been the focus of academic debate. With the development of minimally invasive surgery in recent years, laparoscopic technology has been increasingly mature and widely used in the treatment of gastrointestinal tumors. Compared with distal gastric cancer, the minimally invasive treatment of AEG is in a lagging state, and there are also a series of problems that have not yet reached a consensus. This article reviews and summarizes the recent research progress in two aspects: proximal gastrectomy for AEG and lymph node dissection. Laparoscopic-assisted proximal gastrectomy is safe for early proximal gastric cancer and has a long-term survival outcome not inferior to total gastrectomy, but the surgical indications must be strictly selected. Abdominal lymph node metastasis of AEG is mainly in group 1, 2, 3, and 7, and mediastinal lymph node metastasis is closely related to the length of the infiltrated esophagus. The abdominal transhiatal (TH) approach can obtain a sufficient number of harvested lymph node, and has good safety and efficacy, which is the first-choice of surgical approach for early AEG. The results of the CLASS-10 clinical trial can provide a higher level of evidence for laparoscopic mediastinal lymph node dissection. Laparoscopic surgery for AEG should be carried out in experienced medical center based on clinical research.
Subject(s)
Humans , Adenocarcinoma/surgery , Esophageal Neoplasms/surgery , Esophagogastric Junction/surgery , Gastrectomy/methods , Laparoscopy/methods , Lymph Node Excision/methods , Lymph Nodes/surgery , Retrospective Studies , Stomach Neoplasms/surgeryABSTRACT
Objective:To investigate the influencing factors and regularity of inferior mediastinal lymph node metastasis in Siewert type Ⅱ and Ⅲ adenocarcinoma of esophagogastric junction (AEG).Methods:The retrospective case-control study was conducted. The clinicopatho-logical data of 185 Siewert type Ⅱ and Ⅲ AEG patients in two medical centers (113 cases in Changzhi People's Hospital Affiliated to Changzhi Medical College and 72 cases in Heji Hospital Affiliated to Changzhi Medical College) from January 2017 to January 2022 were collected. There were 143 males and 42 females, aged (64±8)years. Patients underwent radical resection of AEG combined with inferior mediastinal lymph node dissection. Observation indicators: (1) clinicopathological charac-teristics of Siewert type Ⅱ and Ⅲ AEG patients; (2) analysis of influencing factors for inferior mediastinal lymph node metastasis in Siewert type Ⅱ and Ⅲ AEG; (3) regularity of inferior mediastinal lymph node metastasis in Siewert type Ⅱ and Ⅲ AEG. Measurement data with normal distribution were represented as Mean± SD, and comparison between groups was analyzed using the t test. Measurement data with skewed distribution were represented as M(range), and comparison between groups was analyzed using the Mann-Whitney U test. Count data were represented as absolute numbers or percentages, and comparsion between groups was analyzed using the chi-square test or Fisher exact probability. Comparison of ordinal data was analyzed using the rank sum test. Univariate and multivariate analyses were conducted using the Logistic regression model. Results:(1) Clinicopathological characteristics of Siewert type Ⅱ and Ⅲ AEG patients. Pathologic staging as stage Ⅰ, Ⅱ, Ⅲ and Ⅳ, degree of tumor invasion as stage T1, T2, T3 and T4, length of esophageal invasion ≤1 cm, >1 cm and ≤2 cm, >2 cm and ≤3 cm, >3 cm and ≤4 cm were found in 30, 61, 75, 7, 3, 41, 79, 50, 101, 46, 18, 8 cases of the Siewert type Ⅱ and Ⅲ AEG patients without inferior mediastinal lymph node metastasis, respectively, versus 0, 2, 10, 0, 0, 0, 5, 7, 4, 3, 2, 3 cases of the Siewert type Ⅱ and Ⅲ AEG patients with inferior mediastinal lymph node metastasis, showing a significant differences between them ( Z=?2.21, ?2.49, ?2.22, P<0.05). (2) Analysis of influencing factors for inferior mediastinal lymph node metastasis in Siewert type Ⅱ and Ⅲ AEG. Results of univariate analysis showed that pathological staging, depth of tumor invasion and length of esophageal invasion were related factors affecting inferior mediastinal lymph node metastasis in Siewert type Ⅱ and Ⅲ AEG ( odds ratio=2.48, 3.26, 2.03, 95% confidence intervals as 1.02?6.01, 1.21?8.80, 1.18?3.51, P<0.05). Results of multivariate analysis showed that depth of tumor invasion and length of esophageal invasion were independent influening factors affecting inferior mediastinal lymph node metastasis in Siewert type Ⅱ and Ⅲ AEG ( odds ratio=4.01, 2.26, 95% confidence interval as 1.35?11.96, 1.26?4.06, P<0.05). The inferior mediastinal lymph node metastasis probability of AEG patients with the length of esophageal invasion >3 cm and ≤4 cm was 9.47 times that of AEG patients with the length of esophageal invasion ≤1 cm. (3) Regularity of inferior mediastinal lymph node metastasis in Siewert type Ⅱ and Ⅲ AEG. The number of inferior mediastinal lymph nodes including No.110, No.111 and No.112 dissected in 185 patients of Siewert type Ⅱ and Ⅲ AEG were 127, 50 and 27. The number of lymph nodes dissected and the number of metastatic lymph nodes in No.110 and No.111 of patients with length of esophageal invasion ≤1 cm, >1 cm and ≤2 cm, >2 cm and ≤3 cm, >3 cm and ≤4 cm were 69, 4, 42, 4, 4, 1, 12, 4 and 23, 0, 17, 0, 7, 2, 3, 0, respectively. There were significant differences in metastatic lymph nodes in No.110 and No.111 of patients with length of esophageal invasion ≤1 cm, >1 cm and ≤2 cm, >2 cm and ≤3 cm, >3 cm and ≤4 cm ( χ2=8.45, 7.30, P<0.05). Of the 185 patients of Siewert type Ⅱ and Ⅲ AEG, the ratio of cases with inferior mediastinal lymph nodes metastasis was 6.49%(12/185). The ratio of inferior mediastinal lymph nodes metastasis in cases with length of esophageal invasion ≤1 cm, >1 cm and ≤2 cm, >2 cm and ≤3 cm, >3 cm and ≤4 cm were 3.81%(4/105), 6.12%(3/49), 10.00%(2/20), 27.27%(3/11), respectively. The ratio of No.110 lymph nodes metastasis in cases with length of esophageal invasion ≤1 cm, >1 cm and ≤2 cm, >2 cm and ≤3 cm, >3 cm and ≤4 cm were 2.86%(3/105), 6.12%(3/49), 5.00%(1/20), 27.27%(3/11), respectively, showing a significant difference among them ( χ2=8.26, P<0.05). Conclusions:Depth of tumor invasion and length of esophageal invasion are independent influening factors affecting inferior mediastinal lymph node metastasis in Siewert type Ⅱ and Ⅲ AEG. The rate of inferior mediastinal lymph node metastasis increases with the increase of the length of esophageal invasion.
ABSTRACT
In recent years,the incidence of gastric cancer has shown a decreasing trend.However,the incidence of adenocarcinoma of the esophagogastric junction (AEG) is gradually increasing.Different from esophageal cancer and gastric cancer,AEG has distinct pathological types,with low early diagnostic rate and poor prognosis.At present,the main therapeutic measure is surgery for advanced Siewert type Ⅱ and Ⅲ AEG.The key to a successful operation is complete resection of tumor and thorough lymphadenectomy,especially the upper abdominal and inferior mediastinal lymph nodes (No.110 the lower thoracic paraesophageal lymph nodes and No.111 the supradiaphragmatic lymph nodes).For the advanced Siewert type Ⅱ and Ⅲ AEG invading lower thoracic esophagus,it is required to perform gastrectomy with D2 lymphadenectomy,which includes upper abdominal and inferior mediastinal lymphadenectomy.There has been reached a consensus on complete resection of tumor and thorough lymphadenectomy.However,there is still controversy in the inferior mediastinal lymphadenectomy,particularly lower thoracic paraesophageal lymph nodes and supradiaphragmatic lymph nodes.Since specific lymphatic drainage of the esophagogastric junction,it is necessary to dissect inferior mediastinal lymph nodes.The metastatic rate of the inferior mediastinal lymph nodes determines the extent of inferior mediastinal lymphadenectomy.D2 lymphadenectomy (including inferior mediastinal lymphadenectomy) could achieve more thorough clearance for perigastric metastatic lymph nodes.Meanwhile,it could increase the survival rate of postoperative patients and improve their prognosis.