Fluorodeoxyglucose-positron emission tomography scan-positive recurrent papillary thyroid cancer and the prognosis and implications for surgical management

Abstract

BackgroundTo compare outcomes for patients with recurrent or persistent papillary thyroid cancer (PTC) who had metastatic tumors that were fluorodeoxyglucose-positron emission tomography (FDG-PET) positive or negative, and to determine whether the FDG-PET scan findings changed the outcome of medical and surgical management.MethodsFrom a prospective thyroid cancer database, we retrospectively identified patients with recurrent or persistent PTC and reviewed data on demographics, initial stage, location and extent of persistent or recurrent disease, clinical management, disease-free survival and outcome. We further identified subsets of patients who had an FDG-PET scan or an FDG-PET/CT scan and whole-body radioactive iodine scans and categorized them by whether they had one or more FDG-PET-avid (PET-positive) lesions or PET-negative lesions. The medical and surgical treatments and outcome of these patients were compared.ResultsBetween 1984 and 2008, 41 of 141 patients who had recurrent or persistent PTC underwent FDG-PET (n = 11) or FDG-PET/CT scans (n = 30); 22 patients (54%) had one or more PET-positive lesion(s), 17 (41%) had PET-negative lesions, and two had indeterminate lesions. Most PET-positive lesions were located in the neck (55%). Patients who had a PET-positive lesion had a significantly higher TNM stage (P = 0.01), higher age (P = 0.03), and higher thyroglobulin (P = 0.024). Only patients who had PET-positive lesions died (5/22 vs. 0/17 for PET-negative lesions; P = 0.04). In two of the seven patients who underwent surgical resection of their PET-positive lesions, loco-regional control was obtained without evidence of residual disease.ConclusionPatients with recurrent or persistent PTC and FDG-PET-positive lesions have a worse prognosis. In some patients loco-regional control can be obtained without evidence of residual disease by reoperation if the lesion is localized in the neck or mediastinum.

Treatment strategies for radioactive iodine-refractory differentiated thyroid cancer

“…For example, in the DECISION trial, 17% of placebo-treated patients had a PFS longer than 1 year (M. Brose, personal communication). Additionally, in one series of patients, whose tumors were FDG nonavid upon positron emission tomography (PET) imaging, the median survival was 41 months without systemic therapy [Schreinemakers et al 2012]. Hence, the decision to treat should be based on a combination of factors, including tumor size and growth rate, symptoms, and tumor location.…”

Ultrasound-guided Ethanol Ablation: Where does It fit in the Treatment of Recurrent Metastatic Papillary Thyroid Cancer?

“…In general, RAI scan non-avid and FDG avid recurrences are considered clinically more aggressive. 10,11 The five interventions of ETOH ablation described here were not good candidates for further RAI treatment, given that none had positive RAI avidity. We consider FDG avidity as a relative indication for resection, and if not possible, ETOH injection ablation.…”

Value of Fluorodeoxyglucose PET/Computed Tomography Patient Management and Outcomes in Thyroid Cancer

“…[11][12][13] About 20% to 30% of DTC recur, and of these patients 7% die within 10 years of initial diagnosis. 14 Initial treatment, namely complete resection and I-131 therapy, influences the outcome of DTC.…”