JOSE WILLEGAIGNON DE AMORIM DE CARVALHO
Projetos de Pesquisa
Unidades Organizacionais
LIM/43 - Laboratório de Medicina Nuclear, Hospital das Clínicas, Faculdade de Medicina
5 resultados
Resultados de Busca
Agora exibindo 1 - 5 de 5
- Clinical and Dosimetric Variables Related to Outcome After Treatment of Graves' Disease With 550 and 1110 MBq of I-131(2015) SAPIENZA, Marcelo Tatit; COURA-FILHO, George Barberio; WILLEGAIGNON, Jose; WATANABE, Tomoco; DUARTE, Paulo Schiavom; BUCHPIGUEL, Carlos AlbertoTherapy of Graves' hyperthyroidism (HTG) with I-131 is still mostly performed on an empirical basis. The present study was carried out to evaluate clinical and dosimetric variables associated with outcome in HTG therapy, which could contribute to planning and defining the most appropriate activity to be administered. Methods Patients with HTG were randomly assigned to therapy with 555 MBq (15mci) or 1110 MBq (30 mCi) of I-131. Estimation of thyroid radiation absorbed dose was made according to MIRD methodology. Success was defined as clinical/laboratory euthyroidism or hypothyroidism one year after therapy. The association between clinical, laboratory, and dosimetric variables with 1-year outcome was measured using bivariate analysis, followed by logistic regression. Results Ninety-one patients included completed the follow-up. Therapeutic success was observed in 77 (84.6%) of them, in a greater proportion when 1110 MBq of I-131 was administered as compared with 550 MBq (94.8% vs 77.4%, P = 0.02). Besides administered activity, multivariate analysis indicated that outcome was related to patient age and gland mass. A higher therapeutic success rate was achieved with doses greater than 300 Gy as compared with doses less than 300 Gy (89% vs 60%, P = 0.01). Conclusion Administered activity, age, and gland mass were related to the outcome. Radiation absorbed dose, although not significant according to multivariate analysis, may be used as a quantitative parameter in therapy planning, with a target dose of 300 Gy. In cases where a rapid and efficient response to radioiodine treatment is required, adoption of a simplified protocol employing high activities is justified.
- Iodine/FDG ""Flip-Flop"" Phenomenon Inside a Large Metastatic Thyroid Cancer Lesion Better Characterized on SPECT/CT and PET/CT Studies(2018) DUARTE, Paulo Schiavom; MARIN, Jose Flavio Gomes; CARVALHO, Jose Willegaignon de Amorim de; SAPIENZA, Marcelo Tatit; BUCHPIGUEL, Carlos AlbertoIodine/FDG flip-flop phenomenon inside large metastatic thyroid cancer lesions has been rarely described. We present a case of this phenomenon better characterized using SPECT/CT and PET/CT studies.
- Brain Metastasis of Medullary Thyroid Carcinoma Without Macroscopic Calcification Detected First on 68Ga-Dotatate and Then on 18F-Fluoride PET/CT(2018) DUARTE, Paulo Schiavom; MARIN, Jose Flavio Gomes; CARVALHO, Jose Willegaignon De Amorim De; SAPIENZA, Marcelo Tatit; BUCHPIGUEL, Carlos AlbertoWe report a case of a medullary thyroid carcinoma noncalcified brain metastasis characterized on Ga-68-dotatate PET/CT but not on an F-18-fluoride PET/CT performed 1 month later. Subsequent F-18-fluoride PET/CT studies performed 7 and 19 months after the Ga-68-dotatate PET/CT study demonstrated focal uptake in the metastasis. The CT images of the last PET/CT study also depicted a small focus of calcification beginning in the metastatic site.
- Comparison of the Variability of SUV Normalized by Skeletal Volume with the Variability of SUV Normalized by Body Weight in F-18-Fluoride PET/CT(2019) MARIN, Jose Flavio Gomes; DUARTE, Paulo Schiavom; CARVALHO, Jose Willegaignon de Amorim de; SADO, Heitor Naoki; SAPIENZA, Marcelo Tatit; BUCHPIGUEL, Carlos AlbertoOur objective was to test the hypothesis that variability in SUV normalized by skeletal volume (SV) in F-18-fluoride (F-18-NaF) PET/CT studies is lower than variability in SUV normalized by body weight (BW). Methods: The mean SUV (SUVmean) was obtained for whole skeletal volume of interest (wsVOI) in 163 selected F-18-NaF PET/CT studies. These studies were performed to investigate bone metastases and were considered to have normal results. SUVmean was calculated with normalization by BW (BW SUVmean), with normalization by SV (SV SUVmean), and without normalization (WN SUVmean). The total SV for each patient was also estimated on the basis of the wsVOI defined on the CT component of the PET/CT study. SUVmean variability for each patient was estimated as the absolute value of the difference between the SUVmean for the patient and the mean of the SUVmean for the whole group of patients, divided by the mean of the SUVmean for the whole group of patients. The variabilities of SUVmean calculated by the 3 methods were compared using a paired 1-tailed Wilcoxon test. Results: The mean variability for the BW, SV, and WN SUVmean was 0.16, 0.13, and 0.16, respectively. There were statistically significant differences between SV and BW SUVmean variability (P = 0.03) and between SV and WN SUVmean variability (P < 0.01). There was no statistically significant difference between BW and WN SUVmean variability (P = 0.4). Conclusion: In patients with normal F-18-NaF PET/CT results, SV SUVmean presents lower variability than BW SUVmean.
conferenceObject Predicting dosimetry for therapy using imaging analogs of therapeutic radiopharmaceuticals: An uncertainty and sensitivity analysis applicable to Theranostics(2015) JOSEFSSON, Anders; HOBBS, Robert; PLYKU, Donika; HUANG, Kevin; WILLEGAIGNON, Jose; COURA FILHO, George; DUARTE, Paulo; SAPIENZA, Marcelo; SGOUROS, George