食管胃结合部腺癌淋巴结转移规律对根治性放疗靶区勾画参考

The patterns of lymph node metastasis in adenocarcinoma of esophagogastric junction：a reference for target volume delineation in radical radiotherapy

目的：分析食管胃结合部腺癌的淋巴结转移分布特征。方法收集2006—2009年间393例食管胃结合部腺癌病理资料，分析不同 Siewert 分型、肿瘤浸润深度、肿瘤最大径等淋巴结转移特征和分布特点，探讨高危淋巴引流区。χ2检验组间差别。结果食管胃结合部腺癌腹腔淋巴结转移率为69.2％、转移度为31.31％，以贲门、胃小弯、胃左动脉、脾动脉、脾门、肠系膜根部及腹主动脉旁淋巴结转移发生率高。纵隔淋巴结转移率为16.4％、转移度为8.3％，以下段食管旁、食管裂孔及膈上区域淋巴结转移发生率高。 SiewertⅠ型较Ⅱ、Ⅲ型纵隔淋巴结转移率高（P＝0.003），腹腔淋巴结转移度低（P＝0.002）。 T3＋T4期及肿瘤最大径≥6 cm 者淋巴结转移度在腹腔多个区域均高于对照组，纵隔淋巴结转移度在肿瘤最大径组间差别不明显。胃大弯、肝十二指肠韧带和膈下部位淋巴结转移度在不同组间均低于＜10％。结论食管胃结合部腺癌放疗腹腔高危淋巴区域应包括贲门、胃小弯、胃左动脉、脾动脉、脾门旁、肠系膜根部及腹主动脉旁，纵隔高危淋巴引流区包括下段食管旁、食管裂孔及膈上区域，并依据不同 Siewert 分型及临床病理特征的淋巴结转移特点进行个体化靶区设计。

Objective To analyze the patterns and distribution of lymph node metastasis in patients with adenocarcinoma of the esophagogastric junction （ AEG）. Methods The pathological data of 393 patients with AEG from 2006 to 2009 were analyzed. The patterns and distribution of lymph node metastasis were analyzed in patients with different Siewert subtypes, depths of tumor invasion, and maximum diameters of the tumor, and the high.risk lymphatic drainage areas were investigated. Between.group comparison was performed by χ2 test. Results The metastatic rate and ratio of abdominal lymph nodes in AEG were 69. 2%and 31. 31%, respectively. The incidence rates of lymph node metastasis in the cardia, lesser curvature, left gastric artery, splenic artery, splenic hilum, mesenteric root, and abdominal aorta were the highest. The metastatic rate and ratio of mediastinal lymph nodes were 16. 4% and 8. 3%, respectively. The incidence rates of lymph node metastasis in the lower paraesophageal, esophageal hiatus, and superior diaphragmatic areas were the highest. Compared with Siewert type II and type III AEG, Siewert type I AEG had a significantly higher mediastinal lymph node metastatic rate （P= 0. 003） and a significantly lower abdominal lymph node metastatic ratio （P= 0. 002）.The metastatic ratios of lymph nodes in multiple abdominal regions were higher in patients with stage T3＋T4 AEG and a maximum tumor diameter of ≥6 cm than in the control group, while the metastatic ratios of mediastinal lymph nodes in groups with different maximum tumor diameters were similar. The metastatic ratios of lymph nodes in the greater curvature, hepatoduodenal ligament, and inferior diaphragmatic areas were lower than 10% in all groups. Conclusions In radiotherapy for AEG, the abdominal high.risk lymphatic drainage areas involve the cardia, lesser curvature, left gastric artery, splenic artery, splenic hilum, mesenteric root, and abdominal aorta, while the mediastinal high.risk lymphatic drainage areas involve the lower paraesophageal, esophageal hiatus, and superior diaphragmatic areas. In addition, the personalized target volume design should be based on the patterns of lymph node metastasis with different Siewert subtypes and clinical pathological characteristics.