RESUMO
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.
Assuntos
Biomarcadores Tumorais/sangue , Calcitonina/sangue , Antígeno Carcinoembrionário/sangue , Carcinoma Neuroendócrino/diagnóstico por imagem , Neoplasias da Glândula Tireoide/diagnóstico por imagem , Adulto , Idoso , Carcinoma Neuroendócrino/sangue , Criança , Estudos de Coortes , Progressão da Doença , Feminino , Fluordesoxiglucose F18 , Humanos , Masculino , Pessoa de Meia-Idade , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Prognóstico , Compostos Radiofarmacêuticos , Estudos Retrospectivos , Neoplasias da Glândula Tireoide/sangue , Adulto JovemRESUMO
Vinte e oito estudos intercríticos e 9 críticos/pós críticos de tomografia por emissäo de fóton único (SPECT) foram realizados em 27 pacientes com epilepsia do lobo temporal e esclerose mesial temporal. Estudos intercríticos localizaram corretamente a área epileptogênica em 19 (67 por cento) dos pacientes pela análise visual e 16 (61,5 por cento) pela semi quantitativa, com 10,7 e 15,3 por cento, de falsa lateralizaçä respectivamente. Todos os 9 estudos críticos/ pós críticos detectaram o hemosfério epileptogênico e permitiram localizaçäo correta da área epileptogênica em 5 de 9 pacientes cujos exames intercríticos haviam sido inonclusivos. Três estudos realizados durante crises secundariamente generalizadas e simétricas mostraram hiperfluxo restrito ao lobo temporal