BACKGROUND: Neoadjuvant immunochemotherapy (NICT) has shown promising therapeutic benefits in patients with locally advanced gastric cancer (LAGC). Our study aimed to predict the pathological response to NICT in LAGC before surgery by correlating the metabolic parameters of baseline and post-treatment METHODS: Thirty-six LAGC patients who received three cycles of NICT (combination of sintilimab and CapeOx), followed by radical surgery, were included in this study. Both baseline RESULTS: Out of the 36 patients, 13 patients had a good response (GR), which included 5 cases with TRG 0 and 8 cases with TRG 1. Conversely, 23 patients exhibited a poor response (PR), with 20 patients having TRG 2 and 3 patients having TRG 3. Univariate analysis revealed that pMTV and pTLG in the GR group were significantly lower compared to the PR group (all p <
0.05). The identified cutoff values of pMTV and pTLG were 1.68 cm³ (area under the cure (AUC) = 0.683) and 4.71 cm³ (AUC = 0.683) for the GR and PR groups, respectively. On receiver operating characteristic (ROC) curve analyses, these values corresponded to sensitivity, specificity, and accuracy of 68.8%, 80.0%, and 73.1%, respectively, with no statistically significant differences between them after the DeLong test and McNemar test (all p >
0.05). Furthermore, bSUV CONCLUSIONS: Imaging biomarkers from the combination of baseline and post-treatment