GEORGE BARBERIO COURA FILHO

(Fonte: Lattes)
Índice h a partir de 2011
11
Projetos de Pesquisa
Unidades Organizacionais
Instituto do Câncer do Estado de São Paulo, Hospital das Clínicas, Faculdade de Medicina - Médico
LIM/43 - Laboratório de Medicina Nuclear, Hospital das Clínicas, Faculdade de Medicina

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Agora exibindo 1 - 10 de 13
  • article 5 Citação(ões) na Scopus
    Evaluation of Parotid Salivary Gland Echo Texture by Ultrasound Examinations and Correlation With Whole-Body Scintigraphy After Radioiodine Therapy in Patients With Differentiated Thyroid Carcinoma
    (2020) LIMA, Graziele Aparecida Simoes; LOPEZ, Rossana Veronica Mendoza; FREITAS, Ricardo Miguel Costa de; WILLEGAIGNON, Jose; SAPIENZA, Marcelo Tatit; CHAMMAS, Maria Christina; COURA-FILHO, George Barberio
    Objectives This study aimed to evaluate the echo texture of the parotid salivary glands before and after radioiodine therapy (RIT) using ultrasound (US) images in patients with differentiated thyroid cancer and to evaluate the correlations between post-RIT whole-body scintigraphy (WBS) images and US image patterns in salivary and cervical areas. Methods A retrospective study was performed with data on demographic and clinical information, US examinations, and WBS images collected through medical recordings. Results Comparing the US features before and after RIT, significant echo texture heterogeneity was found in 31.3% of all patients evaluated. When evaluated according to the level of iodine 131 (I-131) radioactivity (<5.6, 5.6-<9.3, and >= 9.3 GBq), echo texture heterogeneity was significantly associated with the 5.6-GBq I-131 radioactivity group (P < .001). No association was found for any level of I-131 post-RIT WBS uptake intensity and changes in US feature patterns. Conclusions Ultrasound may be a useful tool for evaluating chronic sialadenitis after RIT, and the I-131 uptake intensity using a routine post-RIT WBS is not associated with US echo texture changes.
  • article 12 Citação(ões) na Scopus
    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 Alberto
    Therapy 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.
  • article 6 Citação(ões) na Scopus
    Estimating 131I biokinetics and radiation doses to the red marrow and whole body in thyroid cancer patients: probe detection versus image quantification
    (2016) WILLEGAIGNON, José; PELISSONI, Rogério Alexandre; LIMA, Beatriz Christine de Godoy Diniz; SAPIENZA, Marcelo Tatit; COURA-FILHO, George Barberio; QUEIROZ, Marcelo Araújo; BUCHPIGUEL, Carlos Alberto
    Abstract Objective: To compare the probe detection method with the image quantification method when estimating 131I biokinetics and radiation doses to the red marrow and whole body in the treatment of thyroid cancer patients. Materials and Methods: Fourteen patients with metastatic thyroid cancer, without metastatic bone involvement, were submitted to therapy planning in order to tailor the therapeutic amount of 131I to each individual. Whole-body scans and probe measurements were performed at 4, 24, 48, 72, and 96 h after 131I administration in order to estimate the effective half-life (Teff) and residence time of 131I in the body. Results: The mean values for Teff and residence time, respectively, were 19 ± 9 h and 28 ± 12 h for probe detection, compared with 20 ± 13 h and 29 ± 18 h for image quantification. The average dose to the red marrow and whole body, respectively, was 0.061 ± 0.041 mGy/MBq and 0.073 ± 0.040 mGy/MBq for probe detection, compared with 0.066 ± 0.055 mGy/MBq and 0.078 ± 0.056 mGy/MBq for image quantification. Statistical analysis proved that there were no significant differences between the two methods for estimating the Teff (p = 0.801), residence time (p = 0.801), dose to the red marrow (p = 0.708), and dose to the whole body (p = 0.811), even when we considered an optimized approach for calculating doses only at 4 h and 96 h after 131I administration (p > 0.914). Conclusion: There is full agreement as to the feasibility of using probe detection and image quantification when estimating 131I biokinetics and red-marrow/whole-body doses. However, because the probe detection method is inefficacious in identifying tumor sites and critical organs during radionuclide therapy and therefore liable to skew adjustment of the amount of 131I to be administered to patients under such therapy, it should be used with caution.
  • article 3 Citação(ões) na Scopus
    Correlação entre volume tireoidiano determinado pelo método de ultrassonografia versus cintilografia e sua implicação em cálculos dosimétricos na terapia com radioiodo na doença de Graves
    (2011) VIEIRA, Lucas de Oliveira; KUBO, Rodrigo; SAPIENZA, Marcelo Tatit; WILLEGAIGNON, Jose; CHAMMAS, Maria Cristina; COURA-FILHO, George Barberio; ONO, Carla Rachel; WATANABE, Tomoco; SADO, Heitor Naoki; BUCHPIGUEL, Carlos Alberto
    Introduction: Graves disease (GD) is the most common cause of hiperthyroidism, and the most common treatment options are surgery, antithyroid drugs and radioiodine therapy. In radiodosimetric calculations to determine radioiodine dosage it is possible to use thyroid volume estimatives based on ultrasound or scintigraphy. Objective: The present study aimed to correlate these methodologies emphasizing volume estimatives and dosimetric implications. Subjects and methods: Were included 103 patients with GD diagnosis and indication of radioiodine treatment. They were submitted to thyroid ultrasound and thyroid scintigraphy. Results and conclusions: Good correlation between both methods was observed, although scintigraphy systematically obtained greater volumes than ultrasound implying in lower estimatives of absorbed dose when scintigraphy is used. Arq Bras Endocrinol Metab. 2011;55(9):696-700
  • article 7 Citação(ões) na Scopus
    Ga-68-DOTATATE PET: temporal variation of maximum standardized uptake value in normal tissues and neuroendocrine tumours
    (2019) COURA-FILHO, George Barberio; HOFF, Ana A. F. O.; DUARTE, Paulo S.; BUCHPIGUEL, Carlos A.; JOSEFSSON, Anders; HOBBS, Robert F.; SGOUROS, George; SAPIENZA, Marcelo T.
    Objectives Higher affinity of Ga-68 compounds to somatostatin receptors (SSTRs) and PET better image resolution increased interest in Ga-68-labelled somatostatin analogs in the management of neuroendocrine tumours (NETs). This study aimed to evaluate the maximum standardized uptake value (SUVmax) variation in sequential somatostatin analogs-PET in NET patients and identify optimal tumour detection and characterization imaging time. Methods Patients with histological or biochemical NET diagnosis performed two to three PET/computed tomography (CT) scans after intravenous injection of Ga-68-DOTATATE: Early PET [EarlyPET: <15 minutes postinjection (p.i.)], diagnostic PET (DiagPET: 45-90 minutes p.i.) and delayed PET (DelayPE: 90-240 minutes p.i.). Up to five tumour sites and normal tissues had SUVmax determined. Time-SUVmax curves were created for the target lesions and normal organs. Ratios between tumour and liver SUVmax (SUVTU/Liver) and tumour/blood pool (SUVTU/BP) were also calculated. Results Twenty-nine patients were included, 16 female, mean age of 46.5 +/- 14.3 years. Average administered activity was 129.5 +/- 29.6 MBq. Kidneys SUVmax was higher in EarlyPET compared with DiagPET (P = 0.04) and DelayPET showed higher SUVmax compared with DiagPET for normal liver, pancreas and kidneys (P = 0.02). No differences were noted between EarlyPET, DiagPET and DelayPET in tumour SUVmax (P > 0.05). SUVTU/Liver and SUVTU/BP did not change between EarlyPET and DiagPET, with a slight decrease in DelayPET. Conclusion Stability in tumour SUVmax values measured at different intervals independently of tumour location, as also in normal tissues as kidneys and liver suggest that a more flexible imaging protocol may be adopted.
  • article 1 Citação(ões) na Scopus
    Comparison of standardized uptake values measured on 18F-NaF PET/CT scans using three different tube current intensities
    (2015) VALADARES, Agnes Araujo; DUARTE, Paulo Schiavom; WOELLNER, Eduardo Bechtloff; COURA-FILHO, George Barberio; SAPIENZA, Marcelo Tatit; BUCHPIGUEL, Carlos Alberto
    Objective: To analyze standardized uptake values (SUVs) using three different tube current intensities for attenuation correction on 18FNaF PET/CT scans. Materials and Methods: A total of 254 18F-NaF PET/CT studies were analyzed using 10, 20 and 30 mAs. The SUVs were calculated in volumes of interest (VOIs) drawn on three skeletal regions, namely, right proximal humeral diaphysis (RH), right proximal femoral diaphysis (RF), and first lumbar vertebra (LV1) in a total of 712 VOIs. The analyses covered 675 regions classified as normal (236 RH, 232 RF, and 207 LV1). Results: Mean SUV for each skeletal region was 3.8, 5.4 and 14.4 for RH, RF, and LV1, respectively. As the studies were grouped according to mAs value, the mean SUV values were 3.8, 3.9 and 3.7 for 10, 20 and 30 mAs, respectively, in the RH region; 5.4, 5.5 and 5.4 for 10, 20 and 30 mAs, respectively, in the RF region; 13.8, 14.9 and 14.5 for 10, 20 and 30 mAs, respectively, in the LV1 region. Conclusion: The three tube current values yielded similar results for SUV calculation.
  • article 3 Citação(ões) na Scopus
    Ultrasonography Echotexture as a surrogate for Sialadenitis secondary to I-131 Radioiodine Therapy for differentiated Thyroid Cancer: a review and metaanalysis
    (2020) LIMA, Graziele Aparecida Simoes; LOPEZ, Rossana Veronica Mendoza; OZORIO, Gislaine Aparecida; FREITAS, Ricardo Miguel Costa de; WILLEGAIGNON, Jose; SAPIENZA, Marcelo Tatit; CHAMMAS, Maria Christina; COURA-FILHO, George Barberio
    To systematically review and analyze the medical literature to assess ultrasonography echotexture changes in thyroid cancer patients for the detection of chronic sialadenitis caused by radioiodine therapy. Methods: Sources were retrieved from PubMed, Scopus, EMBASE and LILACS through November 2018. All studies that assessed ultrasonographic features before I-131 administration and at 12 months after I-131 administration were selected. After data extraction, statistical analysis was performed by using Stata software. Results: From a total of 435 studies, 4 studies involving 665 patients were considered eligible, and echotexture heterogeneity was found with a significant difference. Conclusions: Ultrasound echotexture may detect chronic sialadenitis secondary to salivary radioiodine therapy.
  • article 9 Citação(ões) na Scopus
    Pediatric 131I-MIBG Therapy for Neuroblastoma: Whole-Body 131I-MIBG Clearance, Radiation Doses to Patients, Family Caregivers, Medical Staff, and Radiation Safety Measures
    (2018) WILLEGAIGNON, Jose; CREMA, Karin Paola; OLIVEIRA, Nathalie Canhameiro; PELISSONI, Rogerio Alexandre; COURA-FILHO, George Barberio; SAPIENZA, Marcelo Tatit; BUCHPIGUEL, Carlos Alberto
    Purpose I-131-metaiodobenzylguanidine (I-131-MIBG) has been used in the diagnosis and therapy of neuroblastoma in adult and pediatric patients for many years. In this study, we evaluated whole-body I-131-MIBG clearance and radiation doses received by patients, family caregivers, and medical staff to establish appropriate radiation safety measures to be used in therapy applications. Methods Research was focused on 23 children and adolescents with metastatic neuroblastoma, with ages ranging from 1.8 to 13 years, being treated with I-131-MIBG. Based on measured external dose rates from patients, dosimetric data to patients, family members, and others were calculated. Results The mean SD I-131-MIBG activity administered was 8.55 +/- 1.69 GBq. Percent whole-body retention rates of I-131-MIBG at 24, 48, and 72 hours after administration were 48% +/- 7%, 23% +/- 7%, and 12% +/- 6%, with a whole-body I-131-MIBG effective half-life of 23 +/- 5 hours for all patients. The mean doses for patients were 0.234 +/- 0.096 mGyMBq(-1) to red-marrow and 0.251 +/- 0.101 mGyMBq(-1) to whole body. The maximum potential radiation doses transmitted by patients to others at 1.0 m was estimated to be 11.9 +/- 3.4 mSv, with 97% of this dose occurring over 120 hours after therapy administration. Measured mean dose received by the 22 family caregivers was 1.88 +/- 1.85 mSv, and that received by the 19 pediatric physicians was 43 +/- 51 Sv. Conclusion In this study, we evaluated the whole-body clearance of I-131-MIBG in 23 pediatric patients, and the radiation doses received by family caregivers and medical staff during these therapy procedures, thus facilitating the establishment of radiation safety measures to be applied in pediatric therapy.
  • article 17 Citação(ões) na Scopus
    Effects of Thyroid Hormone Withdrawal and Recombinant Human Thyrotropin on Glomerular Filtration Rate During Radioiodine Therapy for Well-Differentiated Thyroid Cancer
    (2015) COURA-FILHO, George Barberio; WILLEGAIGNON, Jose; BUCHPIGUEL, Carlos Alberto; SAPIENZA, Marcelo Tatit
    Background: Renal function is related to thyroid hormonal status, and glomerular filtration rate (GFR) seems to be impaired in patients with hypothyroidism. The aim of this work was to evaluate quantitatively the effect of hypothyroidism on GFR using a Cr-51-EDTA radioisotope assay. Methods: Twenty-eight patients without known renal disease or dysfunction who had been referred for radioiodine therapy (RIT) after total thyroidectomy were enrolled in this study and divided into two groups. Group A underwent thyroid hormone withdrawal (THW) resulting in hypothyroidism, while group B underwent recombinant human thyrotropin (rhTSH) stimulation and hence remained euthyroid. GFR was assessed by Cr-51-EDTA before and after THW or rhTSH. Results: No clinical differences were observed between the two groups. The meanSD GFRs were 94 +/- 19mL/min/1.73m(2) before THW and 76 +/- 16mL/min/1.73m(2) after THW for group A (p=0.009), and 91 +/- 18mL/min/1.73m(2) before rhTSH and 93 +/- 15mL/min/1.73m(2) after rhTSH for group B (p=0.613). The percent decrease in GFR during hypothyroidism is approximately 18-22%. Conclusion: GFR decreases in patients with normal kidney function during THW for RIT, and rhTSH preserves GFR in these patients. This GFR impairment following thyroidectomy is related to hypothyroidism due to a significant reduction in thyroid hormone levels and is not due to a rise in the TSH level.
  • article 5 Citação(ões) na Scopus
    SPECT-CT-Guided Thoracoscopic Biopsy of Sentinel Lymph Nodes in the Internal Mammary Chain in Patients With Breast Cancer A Pilot Study
    (2016) PIATO, Jose Roberto Morales; FILASSI, Jose Roberto; VEGA, Alberto Jorge Monteiro Dela; COURA-FILHO, George Barberio; AGUIAR, Fernando Nalesso; PORCIUNCULA, Ligia Maria Teixeira Pereira; DORIA, Maira Teixeira; SOARES JR., Jose Maria; BARACAT, Edmund Chada
    Objective: The objective of this study was to determine the impact of the use of single-photon emission computed tomography fused with computed tomography (SPECT-CT) on thoracoscopic biopsy of sentinel lymph nodes (SLNs) in the internal mammary chain in patients with breast cancer by evaluating resultant changes in staging and their clinical implications. Methods: Between September 2010 and January 2014, we performed lymphoscintigraphy-assisted thoracoscopic biopsy of the internal mammary chain SLN in 20 patients with breast cancer. Single-photon emission computed tomography fused with computed tomography was also used in 13 of these patients. The sentinel nodes were surgically identified with the aid of a gamma probe. Results: Sentinel lymph nodes were identified surgically in 19 of 20 patients. In the 13 patients in whom SPECT-CT was used, it readily identified SLNs, especially when they were located over an intercostal space. Change of staging occurred in three patients (15%), two of whom accordingly received adjuvant radiotherapy to the internal thoracic chain. Conclusions: Compared with lymphoscintigraphy alone, the use of SPECT-CT improves localization of the SLN in the internal mammary chain, allowing more accurate planning of each individual's treatment.