CARLOS ALBERTO BUCHPIGUEL
Projetos de Pesquisa
Unidades Organizacionais
Departamento de Radiologia, Faculdade de Medicina - Docente
LIM/43 - Laboratório de Medicina Nuclear, Hospital das Clínicas, Faculdade de Medicina - Líder
LIM/43 - Laboratório de Medicina Nuclear, Hospital das Clínicas, Faculdade de Medicina - Líder
15 resultados
Resultados de Busca
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- 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.
- 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.
- 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.
- 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.
- PET/CT Study Performed After an Oral Administration of F-18-Fluoride(2013) ZACCHI, Samara Riguete; VALADARES, Agnes Araujo; DUARTE, Paulo Schiavom; SAPIENZA, Marcelo Tatit; BUCHPIGUEL, Carlos AlbertoA 52-year-old woman with right breast cancer was referred for F-18-fluoride whole-body PET/CT for the assessment of bone metastases. The peripheral IV access was not obtained after multiple attempts. The radiopharmaceutical was administered by oral route.
- 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 AlbertoPurpose 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.
- Preliminary Comparison of PET/CT Studies Performed After Intravenous and Oral Administration of F-18-Fluoride(2016) ZACCHI, Samara Riguete; VALE, Romulo Hermeto Bueno do; DUARTE, Paulo Schiavom; SAPIENZA, Marcelo Tatit; BUCHPIGUEL, Carlos AlbertoA 78-year-old man with prostate cancer was referred for F-18-NaF PET/CT for assessing bone metastases. An F-18-NaF PET/CT study was performed after the intravenous administration of the radiopharmaceutical. Five days later, a second study was done after oral administration of the radiopharmaceutical as part of a research protocol.
- F-18-FDG PET/CT Osteometabolic Activity in Metastatic Parathyroid Carcinoma(2016) VALE, Romulo Hermeto Bueno do; QUEIROZ, Marcelo Araujo; COUTINHO, Artur Martins Novaes; BUCHPIGUEL, Carlos Alberto; MENEZES, Marcos Roberto deParathyroid cancer is an uncommon type of malignancy, which is frequently associated with poor prognosis. Clinical manifestations are caused by elevated serum calcium and parathyroid hormone (PTH). Diagnostic imaging studies as neck ultrasonography, technetium Tc Tc-99m-sestamibi whole body scintigraphy, CT, and MR are already established tools for this malignancy. Nevertheless, the role of F-18-FDG PET/CT remains unknown in this scenario, with few published studies in literature. Hence, in this article, we aimed to report an illustrative case of increased skeletal FDG uptake associated with high calcium and PTH levels.
- SUV Normalized by Skeletal Volume on F-18-Fluoride PET/CT Studies(2016) CARVALHO, Giovanna; MARIN, Jose Flavio Gomes; GARCEZ, Alexandre Teles; DUARTE, Paulo Schiavom; SAPIENZA, Marcelo Tatit; BUCHPIGUEL, Carlos AlbertoObjective: To propose a technique for SUV normalization on F-18-fluoride PET/CT (F-18-NaF) studies based on skeletal volume and to compare the SUVs normalized by this technique with the ones normalized by body weight. Methods: SUVs were obtained in volumes of interest (VOIs) in proximal diaphyseal regions of the right humerus (HD) and right femur (FD) in 12 selected F-18-NaF studies. The 12 studies presented both regions considered normal by visual examination on PET and CT and were performed in patients presenting body weight below 50 kg (B50) or above 90 kg (A90) (6 patients in each group). The maximum SUVs were calculated in these 2 bone regions in both groups of patients using body weight (SUV BW) and skeletal volume (SUV SV) methodologies. The total skeletal volume for each patient was estimated based on whole skeletal VOIs automatically defined on the CT component of the PET/CT study. The maximum SUVs calculated using the 2 methodologies were compared. Results: The maximum SUVs BW were statistically higher in the group A90 in both regions, with a P < 0.001 and P < 0.008 for FD and HD, respectively. The maximum SUVs SV in the 2 regions were not statistically different between the groups B50 and A90, P values of 0.27 and 0.87 for FD and HD, respectively. Conclusions: The SUVs normalized by skeletal volume present similar results in groups of patients with extremes of body weight. Therefore, this methodology could be more adequate than the one normalized by body weight to semiquantitatively analyze F-18-NaF 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.