Prospective assessment of adenocarcinoma of esophagogastric junction (AEG) following radical resection: Real-world insights from the CLAEG study.
Authors: Zheng Jiabin , Li Yuanfang , Yan Su , Ji Gang , Fan Lin , Hu Wenqing , Li Zhi , Lian Lei , Niu Zhaojian , Wang Quan , Yu Jiang , Li Ziyu , Zang Weidong , Li Yongxiang , Mao Shengxun , Yu Wenbin , Wang Wei , Wu Yongyou , Wei Bo , Li Yong ,   Chinese League of Adenocarcinoma of Esophagoastric Junction (CLAEG Group)
Published: January 2024

TPS415

Background: The CLAEG study (ChiCTR1900026131) is a prospective, real-world data evaluation of the clinical outcomes of patients with AEG following radical resection to investigate lymph node (LN) metastasis patterns and refine treatment strategies. Methods: Data from 44 hospitals in China were collected using a designed CRF, comprising baseline, surgical details, pathology results and recovery progress from January 1,2020. Data cut-off was August 31, 2023. The study is ongoing. Results: A total of 1322 patients were enrolled, and only 946 patients with complete data were included in the analysis. The median age was 65 years (range, 24-90). Among them, 28 patients were classified as Siewert type I, 601 as type II, and 317 as type III. Laparoscopic surgery was performed in 845 patients, while 101 underwent open surgery, with no significant difference in postoperative complication rate between them. However, the laparoscopic group demonstrated superior favorable outcomes in terms of postoperative recovery times, with shorter postoperative exhaust time (3.0 days vs 3.6 days, p<0.001), feeding time (5.0 days vs 5.8 days, p=0.013), discharge time (11.6 days vs 14.6 days, p=0.002), as well as lower intraoperative blood loss (103.9 ml vs 163.4 ml, p=0.001). Among the patients, 891 underwent transhiatal approach, while 55 underwent thoracoabdominal approach, and no significant differences in postoperative complication rates, intraoperative blood loss and hospital stay were observed between these approaches. However, the transhiatal approach was associated with a shorter operative time (244.2 min vs 309.3 min, p<0.001). LN dissection was performed in all patients within the abdominal region, with additional mediastinal LN dissection in 293 patients. The LN metastasis rates were 7.04%, 0% and 5.71% for No. 110, 111 and 112, respectively. Within the abdominal LNs, category-1 nodes included No. 1, 2, 3, 4, 5, 7, 8a, 9, 11, 19, while category-2 included No. 6, 12a, 20. Total gastrectomy was performed in 657 patients, while proximal gastrectomy was performed in 289 patients, and there were no significant differences in the rates of postoperative complications, postoperative recovery times and hospital stay between them. However, total gastrectomy took less operation time (243.7 min vs 258.0 min, p=0.019), and more LNs (36.6 vs 23.3, p<0.001) were detected in abdomen. Conclusion: The CLAEG study confirms the safety and feasibility of laparoscopy in AEG surgery, although its long-term oncology effectiveness requires further investigation. Transhiatal surgery is advantageous due to its shorter operation time. Both proximal and total gastrectomy can be considered as viable surgical options. AEG patients have a higher rate of abdominal LN metastasis but a lower rate of mediastinal node involvement, emphasizing the importance of precise abdominal LN retrieval. Clinical trial information: ChiCTR1900026131 .