Abstract: Analysis on risk factors of synchronous peritoneal carcinomatosis in colorectal cancer and establishment of a clinical prediction model        ZHOU Xue-liang，JIA Hong-tao，SHAO Yan-fei，et al. Department of General Surgery，Ruijin Hospital，Shanghai Jiao Tong University School of Medicine，Shanghai 200025，China 
Corresponding author：SUN Jing，E-mail：sj11788@rjh.com.cn
Abstract    Objective    To construct a risk assessment model for synchronous peritoneal carcinomatosis in colorectal cancer and evaluate its clinical predictive value. Methods    The clinical data of 1670 patients with colorectal cancer treated in the Department of general surgery of Ruijin Hospital, Shanghai Jiao Tong University School of Medicine from September 2013 to March 2021 were retrospectively analyzed. Among them, 104 patients (6.5%) developed synchronous peritoneal carcinomatosis. Univariate and multivariate analyses were used to screen the risk factors of synchronous peritoneal carcinomatosis in colorectal cancer，and a nomogram was constructed to establish the risk assessment model of synchronous peritoneal carcinomatosis in colorectal cancer. Receiver Operating Characteristic Curve （ROC） and AUC values were used to evaluate the accuracy of the model. Results    Univariate analysis showed that obstruction，seroperitoneum，tumor location，cT，cN，hemoglobin，albumin，CA125，CA19-9 and CEA were associated with synchronous peritoneal carcinomatosis in colorectal cancer（P<0.05）. Multivariate analysis showed that tumor site（HR=5.57，95%CI 2.11-14.70，P=0.001）、cT（HR=6.19，95%CI 1.02-37.46，P=0.047）、cN（HR=6.18，95%CI 2.39-15.99，P<0.001）、CA125（HR=27.49，95%CI 8.87-85.17，P<0.001）、CA19-9（HR=46.65，95%CI 12.26-177.58，P<0.001） and CEA（HR=1223.07，95%CI 259.99-5753.70，P<0.001） were independent risk factors for synchronous peritoneal carcinomatosis in colorectal cancer. The total score of the nomogram of the risk assessment model was 278 points and the AUC value of the nomogram was 0.97. Conclusion    Tumor location，cT，cN，CA125，CA19-9 and CEA are risk factors for synchronous peritoneal carcinomatosis in colorectal cancer. The established risk assessment model has good clinical prediction value.

Key words: colorectal cancer, synchronous peritoneal carcinomatosis, risk factor, nomogram 

摘要： 目的    构建结直肠癌同时性腹膜转移风险评估模型并评价其临床预测价值。方法    回顾性分析2013年9月至2021年3月上海交通大学医学院附属瑞金医院普外科收治的1670例结直肠癌病人的临床资料，其中104例（6.5%）发生同时性腹膜转移。单因素和多因素分析筛选影响结直肠癌同时性腹膜转移的风险因素，并构建列线图（Nomogram），从而建立结直肠癌同时性腹膜转移的风险评估模型。采用受试者工作特征曲线（ROC）和AUC值评估模型的准确性。结果    单因素分析结果表明，梗阻、腹腔积液、肿瘤部位、临床T分期（cT）、临床N分期（cN）、血红蛋白、白蛋白、CA125、CA19-9和癌胚抗原（CEA）与结直肠癌同时性腹膜转移相关（P<0.05）。多因素分析结果显示，肿瘤部位（HR=5.57，95%CI 2.11-14.70，P=0.001）、cT（HR=6.19，95%CI 1.02-37.46，P=0.047）、cN（HR=6.18，95%CI 2.39-15.99，P<0.001）、CA125（HR=27.49，95%CI 8.87-85.17，P<0.001）、CA19-9（HR=46.65，95%CI 12.26-177.58，P<0.001）和CEA（HR=1223.07，95%CI 259.99-5753.70，P<0.001）是结直肠癌同时性腹膜转移的独立风险因素。风险评估模型的列线图总分为278分，列线图的AUC值为0.97。结论    肿瘤部位、cT、cN、CA125、CA19-9和CEA是结直肠癌同时性腹膜转移的风险因素，构建的风险评估模型具有较好的临床预测价值。

关键词: 结直肠癌, 同时性腹膜转移, 风险因素, 列线图