Abstract:

Objective This study explored the value of ¹⁸F-FDG PET/CT for delineating the target area in cervical cancer. Methods A total of 33 patients with pathologically proven cervical squamous cell carcinoma in stage IIIB from March 2015 to October 2016 were enrolled. Based on the CT and PET/CT fusion images，3 experienced radiologists outlined the primary tumor target volume （gross target volume，GTV）and compared the differences between the target group and the group. Results Three physicians estimated significantly different GTVs based on pure CT and fusion images （P<0.001）. The LSD-t test showed a significant difference between different groups in GTVCT（F=4.28，P<0.001） but not GTVPET-CT（F=0.21，P=0.81）. Variation in tumor target volume decreased when PET/CT image delineation was used（7.75 cm³ vs 24.50 cm³）. Conclusions PET/CT fusion images can improve the accuracy of target delineation and reduce inter-observer variability.

Key words: Uterine neoplasms, PET/CT fusion image, GTV, CT, Outlining target area, Radiotherapy