Comparative study of18F-FDG positron emission tomography/computed tomography in evaluating tumor volume of primary cervical squamous cell carcinoma based on different tumor metabolic volume measurement methods

Abstract:

Objective: To compare the accuracy of ¹⁸F-FDG PET/CT in measuring the tumor metabolic volume (MTV) of primary tumor volume of cervical squamous cell carcinoma based on different thresholds of maximum standardized uptake value (SUV_max) (iterative adaptive algorithm and 30%, 40%, 50%). Methods: All the included patients withⅠB-ⅣA stage cervical squamous cell carcinoma underwent ¹⁸F-FDG PET/CT and MRI. Threshold MTV method was used to calculate the lesion volumes with different fixed thresholds (30%, 40% and 50% SUV_max) and MTV iterative method was used to calculate the lesion volume directly through AW VolumeShare5 system, and MRI was used to measure the tumor volume in transverse and sagittal position on T2WI by Reformat software. Taking MRI measurement results (MRIv) as the "gold standard", the differences between the results of different MTV measurement methods and MRI were compared, and the linear fitting and correlation analysis were conducted between MTVs and MRIv, and finally the ROC curve was drawn to compare the accuracy. Results: A total of 117 patients met the inclusion criteria. The MTV_30%method and the MTV_iterativemethod were closest to MRIv results, with linear correlation closer to the diagonal; the MTV_iterativemethod had the strongest correlation with MRIv (r=0.98, P=0.000), followed by MTV_30% (r=0.96, P=0.000); the ROC curve showed that the MTV_30%method and the MTV_iterative method were close to the measurement of lesions (z=0.145, P=0.885). Conclusion: MTV_iterativemethod and MTV_30%methods are more accurate in the calculation of lesion size and target delineation of cervical squamous cell carcinoma, which can be used as a reliable basis for the diagnosis and treatment of cervical squamous cell carcinoma.