摘要目的:探讨双源双能量CT多参数成像联合糖类抗原199（CA199）预测胃癌患者接受姑息治疗后1年预后的价值。方法:病例对照研究。选取2022年5月—2023年4月东营市人民医院放射科接受治疗前行双源双能量CT多参数成像扫描的胃癌患者80例，其中男56例、女24例，年龄24~73（59.6±6.4）岁，均接受姑息治疗。姑息治疗后随访1年，根据患者姑息治疗1年后的预后情况分为预后良好组（52例）与预后不良组（28例）。纳入患者一般临床资料（性别、年龄、肿瘤直径、肿瘤分化程度、TNM分期、肿瘤浸润程度、淋巴结转移等），双源双能量CT多参数成像参数［40~100 keV动脉期与静脉期虚拟单能级图像（K 40~100 keV）、碘浓度（IC）、标准化碘浓度（NIC）等］，以及血清CA199表达水平，对胃癌患者姑息治疗后1年预后因素进行单因素分析；将单因素分析结果差异有统计学意义（ P<0.05）的指标进行多因素logistic回归分析独立影响因素；采用受试者操作特征曲线（ROC曲线）验证双源双能量CT多参数成像扫描参数、CA199表达水平单独及联合预测患者姑息治疗1年后预后的效能。 结果:2组患者年龄、肿瘤直径、TNM分期、肿瘤浸润程度、淋巴结转移、动脉期与静脉期K 40~100 keV、IC、NIC及血清CA199水平比较，差异均有统计学意义（ P值均<0.05）。多因素logistic回归分析显示TNM分期、淋巴结转移，动脉期与静脉期K 40~100 keV、IC、NIC，以及血清CA199水平均为预测胃癌患者姑息治疗1年后预后的独立影响因素（ P值均<0.05）。ROC曲线结果，动脉期和静脉期的K 40~100 keV、IC、NIC，以及血清CA199水平单独预测患者预后的曲线下面积（95% CI）分别为0.709（0.589~0.828）和0.877（0.796~0.958）、0.799（0.701~0.897）和0.861（0.764~0.958）、0.791（0.673~0.909）和0.832（0.740~0.925）、0.743（0.628~0.859），灵敏度分别为0.786和0.821、0.786和0.893、0.786和0.821、0.714，特异度分别为0.558和0.750、0.654和0.731、0.788和0.635、0.731，均低于联合预测0.924（0.844~1.000）、0.893、0.962。 结论:双源双能量CT扫描参数联合CA199检测可全面评估胃癌血供特征、代谢活性及肿瘤负荷，较单一指标更能准确预测胃癌姑息治疗后1年预后，为临床决策提供可靠依据。

abstractsObjective:This study aimed to explore the value of dual-source dual-energy CT multiparameter imaging combined with carbohydrate antigen 199 (CA199) in predicting the prognosis of gastric cancer patients one year after palliative care.Methods:In this case-control study, a total of 80 patients with gastric cancer who underwent treatment dual-source CT dual-energy scanning in the Radiology Department of Dongying People's Hospital from May 2022 to April 2023 were selected, including 56 males and 24 females, aged 24-73 (59.6±6.4) years, and all patients received palliative care for gastric cancer. After palliative care, patients were followed up for one year and divided into the good prognosis group (52 cases) and the poor prognosis group (28 cases) in accordance with the prognosis after one year of palliative care. General information, namely, patients' gender, age, tumor diameter, degree of tumor differentiation, TNM stage, depth of tumor invasion, and lymph node metastasis, was included. Some parameters were also used for univariate analysis of prognostic factors in gastric cancer patients, namely, 40-100 keV virtual single-energy level images of the arterial and venous phases (K 40-100 keV), iodine concentration (IC), standardized iodine concentration (NIC), and serum CA199 expression level of dual-source dual-energy CT scanning. To determine the independent influencing factors, multivariate logistic regression analysis was conducted on the indicators with statistical significance in accordance with the univariate analysis results. The receiver operating characteristic curve was used to verify the predictive efficacy of the dual-source dual-energy CT multi-parameter imaging and the CA199 expression level for the prognosis of patients one year after palliative care. Results:Statistically significant differences were found in terms of age, tumor diameter, TNM stage, depth of tumor invasion, lymph node metastasis, K 40-100 keV, IC, NIC, and serum CA199 levels between the arterial and venous phases between the two groups of patients (all P values < 0.05). The results of the multivariate logistic regression analysis also showed that TNM stage, lymph node metastasis, K 40-100 keV in the arterial and venous phases, IC, NIC, and serum CA199 levels were all prognostic factors for gastric cancer patients one year after palliative care (all P values < 0.05). For the curve results of the K 40-100 keV, IC, and NIC in the arterial and venous phases, the areas under the curve (95% CI) of serum CA199 levels were 0.709 (0.589-0.828) and 0.877 (0.796-0.958), 0.799 (0.701-0.897) and 0.861 (0.764-0.958), and 0.791 (0.673-0.909) for the arterial phase, respectively. The corresponding sensitivities for the venous phase were 0.786 and 0.821, 0.786 and 0.893, 0.786 and 0.821, 0.714. In terms of specificities, the values were 0.558 and 0.750, 0.654 and 0.731, 0.788 and 0.635, and 0.731, respectively, all of which were lower than those of the combined diagnosis at 0.924 (0.844-1.000), 0.893, and 0.962. Conclusion:Dual-source dual-energy CT scanning parameters combined with CA199 detection can comprehensively evaluate the blood supply characteristics, metabolic activity, and tumor burden of gastric cancer. Therefore, compared with a single indicator, it can more accurately predict prognosis of gastric cancer one year after palliative care, provide a reliable basis for clinical decision-making.