MARCELO TATIT SAPIENZA
Projetos de Pesquisa
Unidades Organizacionais
Departamento de Radiologia, Faculdade de Medicina - Docente
Instituto de Radiologia, Hospital das Clínicas, Faculdade de Medicina
LIM/43 - Laboratório de Medicina Nuclear, Hospital das Clínicas, Faculdade de Medicina
Instituto de Radiologia, Hospital das Clínicas, Faculdade de Medicina
LIM/43 - Laboratório de Medicina Nuclear, Hospital das Clínicas, Faculdade de Medicina
64 resultados
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- Comparison of different dosimetric methods for red marrow absorbed dose calculation in thyroid cancer therapy(2012) WILLEGAIGNON, Jose; SAPIENZA, Marcelo T.; BUCHPIGUEL, Carlos A.Several dosimetric methods have been proposed for estimating red marrow absorbed dose (RMAD) when radionuclide therapy is planned for differentiated thyroid cancer, although to date, there is no consensus as to whether dose calculation should be based on blood-activity concentration or not. Our purpose was to compare RMADs derived from methods that require collecting patients' blood samples versus those involving OLINDA/EXM software, thereby precluding this invasive procedure. This is a retrospective study that included 34 patients under treatment for metastatic thyroid disease. A deviation of 10 between RMADs was found, when comparing the doses from the most usual invasive dosimetric methods and those from OLINDA/EXM. No statistical difference between the methods was discovered, whereby the need for invasive procedures when calculating the dose is questioned. The use of OLINDA/EXM in clinical routine could possibly diminish data collection, thus giving rise to a simultaneous reduction in time and clinical costs, besides avoiding any kind of discomfort on the part of the patients involved.
- Prevalence of exclusive lower extremity metastases at 18F-NaF PET/CT(2015) ORDONES, Monique Beraldo; VALADARES, Agnes Araujo; DUARTE, Paulo Schiavom; SADO, Heitor Naoki; LIMA, Marcos Santos; CARVALHO, Giovanna; SAPIENZA, Marcelo Tatit; BUCHPIGUEL, Carlos AlbertoAbstract Objective: To evaluate the prevalence of exclusive lower extremity metastases, specifically in the femur and below the knee, observed at 18F-NaF PET/CT. Materials and Methods: One thousand consecutive PET/CT studies were retrospectively evaluated for the presence of exclusive uptake in lower extremities suggesting metastatic involvement. The presumptive diagnoses based on such uptakes were subsequently obtained by evaluation of other imaging studies. Results: No exclusive uptake suggestive of metastasis below the femur was observed in the present series. Exclusive uptake was observed in the proximal femur with a presumptive diagnosis of metastasis in two patients. Conclusion: The prevalence of exclusive metastasis below the femur is low and scanning from head to knees is appropriate in most cases.
bookPart Cintilografia para pesquisa de sangramento intestinal(2017) ONO, Carla Rachel; BUCHPIGUEL, Carlos Alberto; SADO, Heitor Naoki; SAPIENZA, Marcelo TatitconferenceObject Case study: Evaluating the new University of Florida hybrid pediatric phantoms and tissue weighting factors from ICRP Publication 103 for diagnostic dosimetry(2018) JOSEFSSON, Anders; HOBBS, Robert; RANKA, Sagar; SCHWARZ, Bryan; CARVALHO, Jose Willegaignon de Amorim de; BUCHPIGUEL, Carlos Alberto; SAPIENZA, Marcelo Tatit; BOLCH, Wesley; SGOUROS, George- 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.
- 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 AlbertoAbstract 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.
- Complementary findings on 18F-FDG PET/CT and 18F-NaF PET/CT in a patient with Erdheim-Chester disease(2017) SABINO, Daniela; VALE, Romulo Hermeto Bueno do; DUARTE, Paulo Schiavom; SAPIENZA, Marcelo Tatit; BUCHPIGUEL, Carlos Alberto
bookPart Bases do estudo PET com FDG(2012) BUCHPIGUEL, Carlos; SAPIENZA, Marcelo Tatit- Comparison of Oral and IV 18F-NaF PET/CT Administration in the Assessment of Bone Metastases in Patients With Breast or Prostate Cancers(2023) ROCHA, Nelisa Helena; ZACCHI, Samara Riguete; SADO, Heitor Naoki; BUCHPIGUEL, Carlos Alberto; DUARTE, Paulo Schiavom; SAPIENZA, Marcelo TatitPurposeThe aim of this study was to compare oral and IV administrations of F-18-NaF PET/CT for detection of suspicious bone metastatic lesions of breast and prostate cancers.Patients and MethodsThirty-six patients with breast (n = 23) or prostate (n = 13) cancers and high risk for bone metastases were prospectively evaluated. All patients underwent 2 PET/CT studies after IV and oral F-18-NaF administration within a 2 to 23 days interval between them. The maximum SUVs from the same suspicious lesions (& LE;5 index lesions per patient) in both studies were measured. The target-to-background ratio (TBR), defined as the relation between the lesion maximum SUV and the whole skeletal mean SUV, was calculated for each lesion. The TBRs in the same lesion calculated using the 2 administration routes were compared. The agreements between 2 physicians in the definition of the number of lesions in both studies were also assessed using weighted & kappa;.ResultsOne hundred thirty-four pairs of lesions were analyzed. There was no significant statistical difference between the median TBRs (P = 0.212) for IV (10.33) and oral (10.85). Excellent intraobserver agreement was observed between IV and oral routes: weighted & kappa; of 1.0 (95% confidence interval, 0.92-1.0) and 0.92 (95% confidence interval, 0.81-0.99) for physicians 1 and 2, respectively. The interobserver coefficients were 0.82 and 0.87 for ""oral versus oral"" and ""IV versus IV,"" respectively.Conclusions(18)F-NaF PET/CT studies using oral and IV routes present comparable performance; thus, it is possible to use oral route in patients with difficult venous access.
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 AlbertoIntroduction: 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