Value of diffusion MRI versus [18F]FDG PET/CT in detection of cervical nodal metastases in differentiated thyroid cancer patients

Abstract

Background:In differentiated thyroid cancer (DTC) patients, cervical nodal metastasis is a negative prognostic factor. Preoperative imaging plays an important role in treatment planning for nodal metastasis and recurrence.The aim of the study is to compare the diagnostic performance of the diffusion-weighted magnetic resonance imaging (DW-MRI) and the F-18 flurodeoxyglucose positron emission computed tomography ([ 18 F]FDG PET/CT) in detection of cervical nodal deposits in DTC patients. Materal and methods:The study was conducted on 30 patients, each performed both modalities just before the surgery. The gold standard was the pathological specimens with post-operative clinico-radiological follow-up, to assess the diagnostic performance of each modality. Results:Based on pathological and post-operative clinico-radiological follow up data. Sensitivity, specificity, negative predictive value (NPV), positive predictive value (PPV) and accuracy were 84%, 80%, 50%, 95% and 83% for PET/CT compared to 84%, 60%, 42.8%, 91.3% and 80% for DW-MRI.On comparing the diagnostic performance of combined DW-MRI and PET/CT to each modality alone, the sensitivity and NPV were improved to 96% and 80% respectively.Conclusions: [ 18 F]FDG PET/CT study is a valuable diagnostic modality for the assessment of cervical nodal deposits in DTC patients, surpassing DW-MRI. Combined PET/CT and DW-MRI techniques seemed to have synergistic performance, mainly in terms of sensitivity and NPV, for detection of nodal metastases.

Comprehensive Review of the Imaging Recommendations for Diagnosis, Staging, and Management of Thyroid Carcinoma

“…Tracheal invasion as per SHIN grading (Figure 3) Table 6 shows a few of the cross-sectional imaging-based studies for baseline evaluation of thyroid cancer and neck nodes in the last 15 years [48,76,[84][85][86][87]. Synoptic CT reporting template for thyroid carcinoma is attached in Figure S1 [71].…”