TY - JOUR T1 - Increased sensitivity of whole body F-18 FDG PET/CT scan with an extra, high resolution head & neck imaging protocol in detecting recurrent thyroid carcinoma: An ROC study JF - Journal of Nuclear Medicine JO - J Nucl Med SP - 206 LP - 206 VL - 52 IS - supplement 1 AU - Sofia Chatziioannou AU - Nikoletta Pianou AU - Alexandros Georgakopoulos AU - Georgia Kafiri AU - Spiros Pavlou AU - Maria Kallergi Y1 - 2011/05/01 UR - http://jnm.snmjournals.org/content/52/supplement_1/206.abstract N2 - 206 Objectives To evaluate, through a receiver operating characteristic (ROC) study, the impact of an additional, high resolution head & neck F-18 FDG PET/CT scan (HNS) on the detection and diagnosis of abnormal foci in the neck of patients suspected with recurrent thyroid cancer. Methods Forty three patients with a history of differentiated thyroid cancer, elevated thyroglobulin levels and negative I-131 or I-123 whole body scans (WBS), suspected for recurrent thyroid cancer, underwent a WBS followed by an HNS. Data were randomly reviewed by 2 certified nuclear medicine physicians blinded to clinical information and according to an ROC protocol. Five-point rating scales were used for the detection and the benign/malignant classification of findings. The LABMRMC software (xray.bsd.uchicago.edu/krl) was applied for initial data analysis using an expert’s independent review and clinical data as ground truth (collection of biopsy ground truth data is ongoing and analysis may be revised accordingly). Results The area under the ROC curves (AUC) increased with the addition of an HNS for both detection and diagnosis tasks. For the detection of abnormalities, the average AUC increased from 0.75 to 0.81 with a 95% confidence interval of (-.35, .22). For the differentiation between benign and malignant findings, the AUC increased from 0.79 to 0.82 with a 95% confidence interval of (-.11, .22). In partial agreement with prior reports, the additional HNS increased the number of abnormal foci for only one observer by 28% and there did not seem to be a significant correlation between increased number of observed foci and better interpretation performance. Conclusions Our initial analysis suggests that the additional high resolution PET/CT HNS could improve the detection and diagnosis of recurrent thyroid cancer and could potentially become the imaging protocol of choice for these patients ER -