TOMOCO WATANABE
Projetos de Pesquisa
Unidades Organizacionais
Departamento de Radiologia, Faculdade de Medicina
LIM/43 - Laboratório de Medicina Nuclear, Hospital das Clínicas, Faculdade de Medicina
LIM/43 - Laboratório de Medicina Nuclear, Hospital das Clínicas, Faculdade de Medicina
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- Color Duplex Doppler US can Follow up the Response of Radioiodine in Graves' Disease by Evaluating the Thyroid Volume and Peak Systolic Velocity(2020) SANTOS, Thiago Adler Ralho Rodrigues; MARUI, Suemi; WATANABE, Tomoco; LIMA, Nicolau; OZAKI, Claudia Okanobo; CERRI, Giovanni Guido; CHAMMAS, Maria C.Purpose The objective of this study was to prove the efficacy of Doppler ultrasonography (US-Doppler) in the follow-up of patients with GD treated with radioactive iodine. Methods 97 patients (77 female and 20 male) with a mean age of 42 years (SD +/- 15) and with prior diagnosis of GD were treated with radioiodine. In total, 88.5 % achieved euthyroidism or hypothyroidism after treatment. The study was documented before treatment and one, three, and six months after treatment with radioactive iodine (131I) by a single investigator. The volume, echogenicity, echotexture and vascularization of the glands as well as the peak systolic velocity (PSV) of the inferior thyroid arteries were evaluated and compared with the laboratory data. Results Thyroid volume and PSV had a statistically significant correlation with hormone levels (p < 0.05). The mean pre-dose therapeutic thyroid volume was 43.01 +/- 3.88 cm(3) and was 11.58 +/- 11.26 cm(3) 6 months after treatment. The mean PSV before 131I was 90.06 +/- 44.13 cm/s and decreased significantly over time (p < 0.001). Six months after the therapeutic dose, the mean PSV was 32.95 +/- 16.36 cm/s. However, the subjective parameters did not have a significant correlation with the normalization of the thyroid hormones. Conclusion Doppler US was useful for monitoring the therapeutic response of GD patients after treatment with radioiodine by evaluating the thyroid volume and peak systolic velocity.
- 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.
bookPart Paratireoide(2017) WATANABE, Tomocoarticle 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- Graves' disease radioiodine-therapy: Choosing target absorbed doses for therapy planning(2014) WILLEGAIGNON, J.; SAPIENZA, M. T.; COURA-FILHO, G. B.; WATANABE, T.; TRAINO, A. C.; BUCHPIGUEL, C. A.Purpose: The precise determination of organ mass (m(th)) and total number of disintegrations within the thyroid gland ((A) over tilde) are essential for thyroid absorbed-dose calculations for radioiodine therapy. Nevertheless, these parameters may vary according to the method employed for their estimation, thus introducing uncertainty in the estimated thyroid absorbed dose and in any dose-response relationship derived using such estimates. In consideration of these points, thyroid absorbed doses for Graves' disease (GD) treatment planning were calculated using different approaches to estimating the m(th) and the (A) over tilde. Methods: Fifty patients were included in the study. Thyroid I-131 uptake measurements were performed at 2, 6, 24, 48, 96, and 220 h postadministration of a tracer activity in order to estimate the effective half-time (T-eff) of I-131 in the thyroid; the thyroid cumulated activity was then estimated using the Teff thus determined or, alternatively, calculated by numeric integration of the measured time-activity data. Thyroid mass was estimated by ultrasonography (USG) and scintigraphy (SCTG). Absorbed doses were calculated with the OLINDA/EXM software. The relationships between thyroid absorbed dose and therapy response were evaluated at 3 months and 1 year after therapy. Results: The average ratio (+/- 1 standard deviation) between m(th) estimated by SCTG and USG was 1.74 (+/- 0.64) and that between (A) over tilde obtained by Teff and the integration of measured activity in the gland was 1.71 (+/- 0.14). These differences affect the calculated absorbed dose. Overall, therapeutic success, corresponding to induction of durable hypothyroidism or euthyroidism, was achieved in 72% of all patients at 3 months and in 90% at 1 year. A therapeutic success rate of at least 95% was found in the group of patients receiving doses of 200 Gy (p = 0.0483) and 330 Gy (p = 0.0131) when m(th) was measured by either USG or SCTG and (A) over tilde was determined by the integration of measured I-131 activity in the thyroid gland and based on T-eff, respectively. No statistically significant relationship was found between therapeutic response and patients' age, administered I-131 activity (MBq), 24-h thyroid I-131 uptake (%) or T-eff (p >= 0.064); nonetheless, a good relationship was found between the therapeutic response and mth (p >= 0.035). Conclusions: According to the results of this study, the most effective thyroid absorbed dose to be targeted in GD therapy should not be based on a fixed dose but rather should be individualized based on the patient's m(th) and (A) over tilde. To achieve a therapeutic success (i.e., durable euthyroidism or hypothyroidism) rate of at least 95%, a thyroid absorbed dose of 200 or 330 Gy is required depending on the methodology used for estimating m(th) and (A) over tilde. (C) 2014 American Association of Physicists in Medicine.
bookPart Cintilografia de Paratireoides(2012) WATANABE, Tomoco- Outpatient Radioiodine Therapy for Thyroid Cancer A Safe Nuclear Medicine Procedure(2011) WILLEGAIGNON, Jose; SAPIENZA, Marcelo; ONO, Carla; WATANABE, Tomoco; GUIMARAES, Maria Ines; GUTTERRES, Ricardo; MARECHAL, Maria Helena; BUCHPIGUEL, CarlosPurposes: To evaluate the dosimetric effect of outpatient radioiodine therapy for thyroid cancer in members of a patient's family and their living environment, when using iodine-131 doses reaching 7.4 GBq. The following parameters were thus defined: (a) whole-body radiation doses to caregivers, (b) the production of contaminated solid waste, and (c) radiation potential and surface contamination within patients' living quarters. Methods: In total, 100 patients were treated on an outpatient basis, taking into consideration their acceptable living conditions, interests, and willingness to comply with medical and radiation safety guidelines. Both the caregivers and the radiation dose potentiality inside patients' residences were monitored by using thermoluminescent dosimeters. Surface contamination and contaminated solid wastes were identified and measured with a Geiger-Muller detector. Results: A total of 90 monitored individuals received a mean dose of 0.27 (+/- 0.28) mSv, and the maximum dose registered was 1.6 mSv. The mean value for the potential dose within all living quarters was 0.31(+/- 0.34) mSv, and the mean value per monitored surface was 5.58 Bq/cm(2) for all the 1659 points measured. The overall production of contaminated solid wastes was at a low level, being about 3 times less than the exemption level indicated by the International Atomic Energy Agency. Conclusions: This study indicates that the treatment of thyroid cancer by applying radioiodine activities up to 7.4 GBq, on an outpatient basis, is a safe procedure, especially when supervised by qualified professionals. This alternative therapy should be a topic for careful discussion considering the high potential for reducing costs in healthcare and improving patient acceptance.
- Graves Disease Mimicking Solitary Autonomous Nodule at Scintigraphy(2012) MARUI, Suemi; AUGUSTO, Gustavo Akerman; WATANABE, Tomoco
bookPart Terapia do Hipertireoidismo(2012) WATANABE, Tomoco- Absence of mutations in PAX8, NKX2.5, and TSH receptor genes in patients with thyroid dysgenesis(2012) BRUST, Ester S.; BELTRAO, Cristine B.; CHAMMAS, Maria C.; WATANABE, Tomoco; SAPIENZA, Marcelo T.; MARUI, SuemiObjectives: To precisely classify the various forms of TD, and then to screen for mutations in transcription factor genes active in thyroid development. Subjects and methods: Patients underwent ultrasound, thyroid scan, and serum thyroglobulin measurement to accurately diagnose the form of TD. DNA was extracted from peripheral leukocytes. The PAX8, and NKX2.5 genes were evaluated in all patients, and TSH receptor ( TSHR) gene in those with hypoplasia. Results: In 27 nonconsanguineous patients with TD, 13 were diagnosed with ectopia, 11 with hypoplasia, and 3 with athyreosis. No mutations were detected in any of the genes studied. Conclusion: Sporadic cases of TD are likely to be caused by epigenetic factors, rather than mutations in thyroid transcription factors or genes involved in thyroid development. Arq Bras Endocrinol Metab. 2012;56(3):173-7