Prediction of Occult Peritoneal Metastasis of Gastric Cancer Based on CT-Based Body Fat Analysis

IntroductionWe aimed to investigate the predictive value of body fat composition parameters obtained using computed tomography (CT) for preoperative occult peritoneal metastasis (OPM) in gastric cancer.MethodsWe adopted a single-center case-control design and retrospectively analyzed data from 115 patients with gastric cancer who underwent laparoscopic exploration or radical gastrectomy at our hospital between October 2020 and March 2024. Patients were divided into OPM-positive (n = 35) and OPM-negative (n = 80) groups. The visceral adipose tissue (VAT) area, subcutaneous adipose tissue (SAT) area, and mean attenuation of CT images at the central level of the L3 lumbar spine were measured using the sliceOmatic software, and the clinical and imaging characteristics of the patients were analyzed.ResultsSignificant differences were present in the VAT area, VAT/SAT area, mean attenuation of SAT, mean attenuation of VAT, VAT area of different N stages, and lesion sites between the OPM-positive and OPM-negative groups (P < 0.05). Results of a multifactor logistic regression analysis showed that the VAT/SAT area ratio and VAT mean attenuation were independent risk factors for OPM in gastric cancer (P < 0.05). The AUC of the clinical-imaging model in predicting gastric cancer OPM was 0.92 (95% confidence interval, 0.86-0.97). A VAT/SAT area of 1.04 (specificity: 54%, sensitivity: 86%) and a VAT mean attenuation of -83.60 Hounsfield unit (HU) (specificity: 99%, sensitivity:34%) were used as optimal cutoff values for identifying the occurrence of OPM in gastric cancer.ConclusionVAT/SAT area ratio and mean VAT attenuation in body fat composition are potential auxiliary parameters for predicting OPM in gastric cancer.