OBJECTIVE: Calcitonin and carcinoembryonic antigen (CEA) doubling times are established prognostic markers in medullary thyroid cancer (MTC). On the other hand, 18F-fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT) shows an increased rate of detection with high blood tumor marker levels in several cancers. This study aimed to analyze the ability of 18F-FDG PET/CT to determine prognosis in the follow-up of patients with MTC. METHODS: Medical records of 17 patients with MTC who underwent 18F-FDG PET/CT were analyzed retrospectively. All patients were classified into two groups: stable disease or progressive disease. RESULTS: Eight patients presented with progressive disease, and all of them showed 18F-FDG uptake (100%), compared to only 3 of 9 patients who presented in stable condition (33%). 18F-FDG PET/CT results were able to distinguish progressive from stable disease (P = .009). Calcitonin levels >4,020 pg/mL (P = .0004), CEA levels >26.8 ng/mL (P = .04), and a calcitonin doubling time <24.1 months (P = .015) were associated with progressive disease in our cohort. The proportion of variance explained that predicted progressive disease was 32% for 18F-FDG uptake, 27.1% for a calcitonin doubling time of 24.1 months, and 41.2% for doubling time plus 18F-FDG PET/CT. CONCLUSION: 18F-FDG uptake was able to distinguish progressive from stable disease. However, this tool should not replace the validated calcitonin doubling time, but rather the combination of information could improve the clinical re-assessment and better identify high-risk patients who require more careful surveillance. ABBREVIATIONS: CEA = carcinoembryonic antigen CT = computed tomography 18F-FDG = 18F-fluorodeoxyglucose MTC = medullary thyroid cancer PET = positron emission tomography PVE = proportion of variance explained sCT = serum calcitonin SUV = standard uptake value US = ultrasound.
OBJECTIVE:Calcitonin and carcinoembryonic antigen (CEA) doubling times are established prognostic markers in medullary thyroid cancer (MTC). On the other hand, 18F-fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT) shows an increased rate of detection with high blood tumor marker levels in several cancers. This study aimed to analyze the ability of 18F-FDG PET/CT to determine prognosis in the follow-up of patients with MTC. METHODS: Medical records of 17 patients with MTC who underwent 18F-FDG PET/CT were analyzed retrospectively. All patients were classified into two groups: stable disease or progressive disease. RESULTS: Eight patients presented with progressive disease, and all of them showed 18F-FDG uptake (100%), compared to only 3 of 9 patients who presented in stable condition (33%). 18F-FDG PET/CT results were able to distinguish progressive from stable disease (P = .009). Calcitonin levels >4,020 pg/mL (P = .0004), CEA levels >26.8 ng/mL (P = .04), and a calcitonin doubling time <24.1 months (P = .015) were associated with progressive disease in our cohort. The proportion of variance explained that predicted progressive disease was 32% for 18F-FDG uptake, 27.1% for a calcitonin doubling time of 24.1 months, and 41.2% for doubling time plus 18F-FDG PET/CT. CONCLUSION:18F-FDG uptake was able to distinguish progressive from stable disease. However, this tool should not replace the validated calcitonin doubling time, but rather the combination of information could improve the clinical re-assessment and better identify high-risk patients who require more careful surveillance. ABBREVIATIONS: CEA = carcinoembryonic antigen CT = computed tomography 18F-FDG = 18F-fluorodeoxyglucose MTC = medullary thyroid cancer PET = positron emission tomography PVE = proportion of variance explained sCT = serum calcitonin SUV = standard uptake value US = ultrasound.
Authors: Han Zhang; Daqi Zhang; Chengqiu Sui; Jingting Li; Canxiao Li; Qiao He; Rui Du; Yishen Zhao; Yantao Fu; Le Zhou; Tie Wang; Gianlorenzo Dionigi; Nan Liang; Hui Sun Journal: Ann Transl Med Date: 2022-06