18F-FDG PET/CT IN DIFFERENTIATED THYROID CARCINOMA.

AIM: Fluorine-18-fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG PET/CT) become an important tool in oncology by combining the metabolic information from 18F-FDG PET with the morphological information of CT. The main objective of this study was to assess the diagnostic value of PET/CT in patients with differentiated thyroid carcinoma (DTC). MATERIAL AND METHODS: We analyzed 173 PET/CT scans of patients with DTC presenting elevated thyroglobulin (Tg) levels, negative Tg-antibodies levels, negative Iodine-131 whole-body scanning (I-131 WBS) and without any signs of clinical or other imaging technique for tumor recurrence/metastases. RESULTS: PET/CT scans were positive in 38% of cases (65/173). The sensitivity, specificity, positive predictive values and the accuracy of PET/CT imaging were 88.09%, 98.6%, 93.1% respectively 96.53%. After the PET/CT scan 29 patients underwent surgery, 24 of them continued radio-iodine therapy, 5 patients initiated tyrosine kinase inhibitors treatment and external radiotherapy. CONCLUSION: 18F-FDG PET/CT is a valuable imaging technique which has the capability of identifying those cases of thyroid recurrence/metastases with elevated Tg levels and negative I-131 WBS. The treatment strategy was changed in 89.2% cases of positive PET/CT scans which shows us that 18F-FDG PET/CT imaging should be integrated into the follow-up programs for DTC patients.

CIRCULATING TUMOR CELLS IN MINIMALLY INVASIVE FOLLICULAR THYROID CARCINOMA AND BENIGN THYROID TUMORS WITH A FOLLICULAR PATTERN: PILOT EXPERIENCE.

PURPOSE: Minimally invasive follicular thyroid carcinomas (MIFCs) are uncommon; literature offers limited guidance on their natural history and management. Starting January 2015 we measured circulating tumor cells (CTCs) in patients with MIFC (n=22) or benign thyroid tumors with follicular features (n=4). METHODS: In a retrospective analysis, we assessed detectability of and serial changes in CTC, compared demographic/clinical differences between CTC-positive versus CTC-negative subgroups using Student's t-test, and examined correlations between CTC status and serum thyroglobulin using Spearman's test. CTCs were quantitated via immunomagnetic separation/microscopic inspection. RESULTS: Thirteen patients (50%: 12/22 MIFC, 1/4 benign tumor) were initially CTC-positive; 3 remained CTC-positive in ≥1 subsequent measurement. CTC-positive patients had larger tumors and more frequent multifocality and vascular invasion versus CTC-negative patients (n=13). However, no tested variable differed significantly between the subgroups. After 17.2±10.5 months, neither subgroup showed evidence of disease. Significant correlation was absent (p ≥ 0.263) between CTC and Tg negativity (r = 0.243; n=13 evaluable) or initial CTC positivity and Tg positivity (r = -0.418; n=9 evaluable). CONCLUSIONS: In the studied settings, CTC measurement is feasible, has unclear clinical/outcome implications, but may provide different information versus thyroglobulin testing. Lengthier assessment is warranted in larger series.

EVALUATION OF CARDIOVASCULAR RISK AND MYOCARDIAL PERFUSION IN PATIENTS WITH RADICALLY TREATED DIFFERENTIATED THYROID CARCINOMA AND REPEATED EPISODES OF IATROGENIC HYPOTHYROIDISM.

CONTEXT: Patients with radically treated differentiated thyroid carcinoma (DTC) undergo multiple episodes of iatrogenously-acquired hypothyroidism for the oncological follow-up. In some patients, this elevates high-sensitive C-reactive protein (hsCRP), a cardiovascular risk biomarker. OBJECTIVE: We wanted to determine if there is any correlation between repeated hypothyroidism episodes, elevated hsCRP and an increased cardiovascular risk as stated through myocardial perfusion. DESIGN: Between July 2014-January 2015, we analyzed serological levels of hsCRP for identifying our patients' cardiovascular risk; we performed a myocardial perfusion scintigraphy to observe the alterations. SUBJECTS AND METHODS: We included 27 patients (n=27), mean age of 52±10: CI (95%),14 female, all disease- free after thyroidectomy, radioiodine ablation and chronic thyroid hormone treatment. We assigned the cardiovascular risk category for each patient according to hsCRP levels; all patients underwent a myocardial perfusion scintigraphy in order to determine the cardiac perfusion index (CPI). RESULTS: hsCRP has been higher in > 65 years old male patients with more than 5 thyroid hormone withholdings. hsCRP is significantly associated with CPI (p=0.001). Spearman's rank correlation indicates a strongly positive linear correlation between these two parameters (r=0.745). CONCLUSIONS: Repeated thyroid hormonal withdrawals in patients with DTC during the long-term follow-up elevated hsCRP at cardiovascular risk levels, having an impact on myocardial perfusion.