Efficiency of spectral CT iodine concentration value related parameters in diagnosis of regional lymph node metastasis of gastric adenocarcinoma / 中华放射学杂志

ABSTRACT

Objective:To analyze the efficacy of quantitative parameters related to spectral CT iodine concentration (IC) values in evaluating regional lymph node metastasis in patients with gastric adenocarcinoma.Methods:The clinical data and CT images of 55 patients with gastric adenocarcinoma diagnosed by pathology from June 2021 to June 2022 were collected retrospectively at Shengjing Hospital of China Medical University. Patients were divided into lymph node metastatic lesion group (32 cases) and lymph node non-metastatic lesion group (23 cases) according to whether there were metastatic lymph nodes in all the lymph nodes examined in the pathological results. Then lymph nodes were taken as the research object, and all lymph nodes were divided into the metastatic lymph node group (25 lymph nodes) and the non-metastatic lymph node group (27 lymph nodes) according to the nature of lymph nodes recorded in the pathological report. The IC values and normalized IC (nIC) values of gastric cancer lesions and lymph nodes in the arterial and venous phases (ICa and ICp, nICa and nICp) were obtained. The difference of IC and nIC values between arterial and venous phases (?IC and ?nIC) were calculated, and the arterial enhancement fraction (AEF, ratio of ICa and ICp of lymph nodes ) was calculated. Student′s t test or Mann-Whitney U test was used to compare the differences of quantitative parameters between the two groups. The parameters with statistical differences were analyzed by the receiver operating characteristic curve to obtain the diagnostic efficacy of each parameter in evaluating lymph node metastasis of gastric cancer, and the Z test was used to compare the area under the curve (AUC) of each parameter. Results:The ICp, nICp, ?IC and ?nIC of the lymph node metastatic lesion group were higher than those of the lymph node non-metastatic lesion group (all P<0.05). The AUC were 0.738, 0.746, 0.811 and 0.821. The short diameter, ICa, nICa and AEF values of lymph nodes in the metastatic lymph node group were higher than those in the non-metastatic lymph node group (all P<0.05). The AUC were 0.821, 0.832, 0.734 and 0.863. There were significant differences in AUC between ICp and ?IC, ?nIC ( Z=2.41, 3.29, P=0.016, 0.001), and between nICp and ?IC, ?nIC ( Z=2.10, 3.09, P=0.036, 0.002) in gastric cancer lesions. There were statistically significant differences in AUC between nICa and ICa, AEF ( Z=2.09, 2.41, P=0.037, 0.016) in lymph nodes. Conclusions:The quantitative parameters related to IC values of spectral CT can be applied to evaluate the properties of regional lymph nodes in patients with gastric adenocarcinoma, where ?IC, ?nIC of lesions and AEF of lymph nodes have the best efficacy.