Multiparametric PET/MR (PET and MR-IVIM) for the evaluation of early treatment response and prediction of tumor recurrence in patients with locally advanced cervical cancer
To assess the value of 18F-FDG PET and MR-IVIM parameters before and during concurrent chemoradiotherapy (CCRT) for evaluating early treatment response and predicting tumor recurrence in patients with locally advanced cervical cancer (LACC) using a hybrid PET/MR scanner.
Fifty-one patients with LACC underwent pelvic PET/MR scans with an IVIM sequence at two time-points (pretreatment [pre] and midtreatment [mid]). Pre- and mid-PET parameters (SUVmax, MTV, TLG) and IVIM parameters (D, F, D*) and their percentage changes (Δ%SUVmax, Δ%MTV, Δ%TLG, Δ%D, Δ%F, Δ%D*) were calculated. We selected independent imaging parameters and built a combined prediction model incorporating imaging parameters and clinicopathological risk factors. The performance of the combinative evaluation for tumor early shrinkage rates (TESR) and the prediction model for tumor recurrence was assessed.
Thirty-two patients were classified into the good response (GR) group with TESR ≥ 50%, and 19 patients were categorized into the poor response (PR) group with TESR < 50%. Δ%D (p = 0.013) and Δ%F (p = 0.006) are independently related to TESR with superior combined diagnostic ability (AUC = 0.901). Pre-TLG, Δ%D, and suspicious lymph node metastasis (SLNM) were selected for the construction of the combined prediction model. The model for identifying the patients with high risk of tumor recurrence reached a moderate predictive ability and good stability with c-index of 0.764 (95% CI, 0.672–0.855).
The combined prediction model based on pretreatment PET metabolic parameter (pre-TLG), IVIM-D percentage changes, and LNs status provides great potential to identify the LACC patients with high risk of recurrence at early stage of CCRT.
• PET/MR plus IVIM offers various complementary information for LACC.
• IVIM-D and IVIM-F percentage changes are independently related to tumor early shrinkage rates.
• The combined prediction model can help identify the LACC patients with high risk of tumor recurrence.
KeywordsConcurrent chemoradiotherapy Positron emission tomography Diffusion magnetic resonance imaging Cervical cancer
Apparent diffusion coefficient
Slow diffusion coefficient
Fast diffusion coefficient
Perfusion-related diffusion fraction
Federation International of Gynecology and Obstetrics
Intravoxel incoherent motion
Locally advanced cervical cancer
Magnetic resonance imaging
Metabolic tumor volume
Positron emission tomography
Receiver operator characteristic
Region of interest
Suspicious lymph nodes metastasis
Maximum standardized uptake value
Tumor early shrinkage rates
Total lesion glycolysis
Volume of interest
- Week 4
The end of the fourth week during CCRT
All authors sincerely thank Dr. Shengtao Lin, Dr. Zhongwei Chen, and SAGE Language Service Team for providing language help on the writing of the paper. The authors also thank Dr. Qijun Wu for his constructive advice on the statistical analysis.
This study has received funding by the National Natural Science Foundation of China (No.81401438), LIAONING Science & Technology Project (No.2017225012).
Compliance with ethical standards
The scientific guarantor of this publication is Dr. Hongzan Sun.
Conflict of interest
The authors of this manuscript declare no relationships with any companies, whose products or services may be related to the subject matter of the article.
Statistics and biometry
An expert in statistics Dr. Qijun Wu kindly provided statistical advice for this manuscript.
Written informed consent was obtained from all patients in this study.
Institutional Review Board approval from Ethics Committee of Shengjing Hospital affiliated to China Medical University (Shenyang, China) was obtained.
• prognostic study
• performed at one institution