Abstract:Objective To analyze the correlation between tumor-related factors and lower limb venous thrombosis after operation of gastric malignant tumor, so as to provide reference for postoperative thrombosis prevention and treatment of tumor patients.Methods From October 2016 to December 2018, 258 patients with gastric malignant tumor who were admitted to gastrointestinal surgery in the First Affiliated Hospital of Zhengzhou University were monitored by color Doppler ultrasound for venous thrombosis of lower extremity before and after operation. The thrombosis of lower extremity before and after operation, and the clinical parameters related to tumor factors were counted, and the effect on DVT of lower extremity was analyzed.Results A total of 135 patients were enrolled in the study. Postoperative DVT occurred in 60 patients (44.4%), including 19 patients (14.1%) with left lower limb, 11 patients (8.1%) with right lower limb, and 30 patients (22.2%) with bilateral lower limb. Univariate chi-square analysis showed that preoperative neoadjuvant chemotherapy and postoperative blood CA125 level increased by more than 5 u/ml were the risk factors of postoperative lower limb thrombosis (P < 0.05). Multivariate analysis was carried out on the increase of blood CA125 level over 5 u/ml after surgery and neoadjuvant chemotherapy. The results showed that the increase of blood CA125 level over 5 u/ml [R = 3.227 (95% CI: 1.181, 8.812)] after surgery was a risk factor for postoperative lower limb thrombosis. Fisher exact probability method was used to analyze the remission rate of thrombi group and non-thrombi group after neoadjuvant chemotherapy. The results showed that the remission rate of non-thrombi group was higher and the difference was statistically significant (P = 0.018).Conclusion The incidence of postoperative lower limb thrombosis was significantly increased in patients with postoperative blood CA125 level increased by more than 5 U/ml compared with that before operation. Patients with remission after neoadjuvant chemotherapy have a lower risk of postoperative thrombosis.