Application of different threshold delineation methods in evaluation of nasopharyngeal carcinoma range on 18F-FDG and 11C-choline PET/CT imaging
10.3760/cma.j.cn321828-20241104-00381
- VernacularTitle:不同阈值勾画法在 18F－FDG和 11C－胆碱PET/CT显像中评价鼻咽癌病灶范围的应用
- Author:
Xiaoli WANG
1
;
Xiaoli LAN
1
;
Jia HU
1
;
Shuqian FENG
1
;
Chunyan LI
1
;
Fan HU
1
Author Information
1. 华中科技大学同济医学院附属协和医院核医学科、分子影像湖北省重点实验室，武汉 430022
- Publication Type:Journal Article
- Keywords:
Nasopharyngeal neoplasms;
Fluorodeoxyglucose F18;
Fluorine radioisotopes;
Choline;
Carbon radioisotopes;
Positron-emission tomography;
Tomography, X-ray com
- From:
Chinese Journal of Nuclear Medicine and Molecular Imaging
2025;45(11):678-683
- CountryChina
- Language:Chinese
-
Abstract:
Objective:To evaluate whether there is a difference between the lesion volumes detected by 18F-FDG PET/CT imaging and 11C-choline PET/CT imaging based on different threshold delineation methods in patients with nasopharyngeal carcinoma, and to recommend a more clinically appropriate threshold method with reference to lesion volume detected by enhanced MRI. Methods:A retrospective study was conducted on 37 patients(27 males, 10 females, age (51.2±11.9) years) with nasopharyngeal carcinoma diagnosed in Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, between October 2015 and May 2017. All patients underwent nasopharyngeal enhanced MRI, 18F-FDG PET/CT and 11C-choline PET/CT scans. Advantage Workstation 4.6 software was used to fuse images of the 3 imaging examinations. The lesion contour was sketched manually based on enhanced MRI sequences to obtain VMRI, and the lesion was sketched in PET images to obtain the corresponding metabolic tumor volume (MTV) by absolute threshold method, relative threshold method and background threshold method respectively. The correlation between ROIs sketched by different threshold methods and ROI in MRI was evaluated by using the Dice similarity coefficient (DSC). Friedman test or repeated measures analysis of variance (corrected by Greenhouse-Geisser) was employed to analyze the differences of MTV or DSC obtained by using 3 threshold methods. Wilcoxon signed-rank test or paired t-test was used to compare the data of different imaging methods. Results:In 18F-FDG PET/CT results, MTVs obtained by using the absolute threshold method, relative threshold method, and background threshold method were 13.21(5.47, 23.16), 10.13(5.67, 16.81), and 13.68(5.77, 25.52)mm 3, respectively, with significant differences ( χ2=17.89, P<0.001). The corresponding DSC differences for the 3 methods were also significant (0.43±0.19, 0.38±0.17 and 0.44±0.17; F=16.35, P<0.001). In 11C-choline PET/CT results, MTV differences based on the 3 threshold methods were significantly different (14.96(6.80, 32.27), 16.28(12.23, 32.47) and 18.97(14.38, 37.02)mm 3;χ2=10.45, P=0.005), and the DSC differences were also significant (0.52±0.21, 0.58±0.13 and 0.62±0.13; F=16.37, P<0.001). The differences in MTV and DSC between FDG and choline groups were also significant ( Z=-3.87, t=-5.57, both P<0.001). The differences between MTVs of 18F-FDG imaging/ 11C-choline imaging and VMRI (24.35(14.48, 36.89)mm 3) were all significantly different ( Z values: from -5.03 to -2.59, all P<0.05). Conclusions:Compared with 18F-FDG PET/CT, the preoperative 11C-choline PET/CT imaging in patients with nasopharyngeal carcinoma is closer to enhanced MRI (gold standard) in the lesion delineation. Compared with ROIs of the other 2 threshold delineation methods, the ROI obtained by the background threshold method is closer to that in enhanced MRI.
