18F-FDG PET/CT metabolic parameters for prediction of treatment response to neoadjuvant immunochemotherapy in locally advanced gastric cancer
10.3760/cma.j.cn321828-20241029-00372
- VernacularTitle:18F－FDG PET/CT代谢参数预测局部进展期胃癌新辅助化疗联合免疫治疗疗效
- Author:
Peng LI
1
;
Shuang LU
1
;
Weiwei ZHAO
1
;
Yanmei LI
1
;
Xianhua HAN
1
;
Xiaofeng ZHANG
1
;
Jianwei YANG
1
Author Information
1. 郑州大学附属肿瘤医院（河南省肿瘤医院）PET－CT中心、河南省肿瘤PET影像医学重点实验室，郑州 450008
- Publication Type:Journal Article
- Keywords:
Stomach neoplasms;
Neoadjuvant therapy;
Immunotherapy;
Positron-emission tomography;
Tomography, X-ray computed;
Fluorodeoxyglucose F18;
Treatment outcome
- From:
Chinese Journal of Nuclear Medicine and Molecular Imaging
2025;45(11):648-653
- CountryChina
- Language:Chinese
-
Abstract:
Objective:To investigate the value of midtreatment 18F-FDG PET/CT metabolic parameters for predicting the pathological response in patients with locally advanced gastric cancer (LAGC) after neoadjuvant immunochemotherapy (NICT). Methods:Twenty-five LAGC patients (19 males, 6 females, age: (64.8±8.6) years) who underwent 18F-FDG PET/CT after NICT in Henan Cancer Hospital from August 2019 to June 2024 were retrospectively analyzed. The lesion′s ROI was delineated, then the SUV max and metabolic tumor volume (MTV) were measured, and the SUV max was divided by SUV mean of the descending aorta to obtain the tumor-to-background ratio (TBR). Patients underwent surgery after PET/CT imaging. Based on the tumor regression grade (TRG) system by the American Joint Committee on Cancer (AJCC) criteria on surgical specimen, patients were divided into responders (TRG0+ 1) and non-responders (TRG2+ 3). Independent-sample t test, Mann-Whitney U test, one-way analysis of variance, and Kruskal-Wallis rank-sum test were used to compare the differences of data. The predictive efficacy of PET/CT metabolic parameters was assessed by the ROC curve analysis. Results:Postsurgical pathology showed that 9 patients were responders and 16 were non-responders. The SUV max (3.10±1.95) and TBR (2.44±1.54) of primary lesions in responders were lower than those in non-responders (7.40±4.68, 5.85±3.74; t values: -2.61, -2.59, both P<0.05), while the MTV of primary tumors and short diameter and metabolic parameters of positive lymph nodes were not significantly different between those 2 groups ( t=-1.50, Z values: -1.09 to -0.75, all P>0.05). No significant relation was found between PET/CT parameters and pathological differentiation or Lauren classification, or other pathological features ( t values: -1.55 to 1.38, Z values: -1.84 to 0, F values: 0.12-2.43, H values: 0.13-0.98, all P>0.05). ROC curve showed that the cut-off value of SUV max for predicting postoperative TRG was 5.40, and the AUC reached 0.77 (95% CI: 0.56-0.91), with the sensitivity and specificity of 9/16, 9/9, respectively. With TBR=3.54 as the cut-off value, its AUC reached 0.77 (95% CI: 0.56-0.91), and the sensitivity and specificity were 11/16, 8/9, respectively. The sensitivity and specificity of PET/CT for predicting lymph node positivity of patients were 8/12 and 13/13, respectively. Conclusion:Interim 18F-FDG PET/CT metabolic parameters can accurately predict the pathological response of LAGC patients after NICT.
