RESUMO
Cervical uptake detected by 131I whole body scintigraphy (131I-WBS) may be due to thyroid remnants or loco-regional metastases. We describe a patient with follicular carcinoma submitted to total thyroidectomy. 131I-WBS showed left cervical linear uptake and focal areas of uptake in the abdomen and pelvis. SPECT/CT images demonstrated a potential thrombus in the left jugular vein (confirmed by doppler neck ultrasound and MRI) as well as bone metastases. The patient was submitted to thrombectomy and histopathology confirmed metastasis of follicular carcinoma.
Assuntos
Adenocarcinoma Folicular/patologia , Veias Jugulares/diagnóstico por imagem , Imagem Multimodal , Neoplasias da Glândula Tireoide/patologia , Tomografia Computadorizada de Emissão de Fóton Único , Tomografia Computadorizada por Raios X , Feminino , Humanos , Radioisótopos do Iodo , Pessoa de Meia-Idade , Metástase NeoplásicaRESUMO
CONTEXT AND OBJECTIVE: Studies using radionuclides are the most appropriate method for estimating renal function. Dimercaptosuccinic acid chelate labeled with technetium-99m (99mTc-DMSA) is the radiopharmaceutical of choice for high-resolution imaging of the renal cortex and estimation of the functional renal mass. The aim of this study was to evaluate a simplified method for determining the absolute renal uptake (ARU) of 99mTc-DMSA prior to nephrectomy, using the radioactivity counts of nephrectomy specimens as the gold standard. DESIGN AND SETTING: Prospective study at the Division of Nuclear Medicine, Department of Radiology, Universidade Estadual de Campinas. METHODS: Seventeen patients (12 females; range 22-82 years old; mean age 50.8 years old) underwent nephrectomy for various reasons. Renal scintigraphy was performed three to four hours after intravenous administration of a mean dose of 188.7 MBq (5.1 mCi) of 99mTc-DMSA, which was done six to 24 hours before surgery. The in vivo renal uptake of 99mTc-DMSA was determined using the radioactivity of the syringe before the injection (measured using a dose calibrator) and the images of the syringe and kidneys, obtained from a scintillation camera. After surgery, the reference value for renal uptake of 99mTc-DMSA was determined by measuring the radioactivity of the nephrectomy specimen using the same dose calibrator. RESULTS: The ARU measurements were very similar to those obtained using the reference method, as determined by linear regression (r-squared = 0.96). CONCLUSION: ARU estimation using the proposed method before nephrectomy seems to be accurate and feasible for routine use.