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
11 resultados
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conferenceObject 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- Diagnostic performance of Ga-68-PSMA-11 PET/MRI-guided biopsy in patients with suspected prostate cancer: a prospective single-center study(2021) FERRARO, Daniela A.; BECKER, Anton S.; KRANZBUHLER, Benedikt; MEBERT, Iliana; BALTENSPERGER, Anka; ZEIMPEKIS, Konstantinos G.; GRUNIG, Hannes; MESSERLI, Michael; RUPP, Niels J.; RUESCHOFF, Jan H.; MORTEZAVI, Ashkan; DONATI, Olivio F.; SAPIENZA, Marcelo T.; EBERLI, Daniel; BURGER, Irene A.Purpose Ultrasound-guided biopsy (US biopsy) with 10-12 cores has a suboptimal sensitivity for clinically significant prostate cancer (sigPCa). If US biopsy is negative, magnetic resonance imaging (MRI)-guided biopsy is recommended, despite a low specificity for lesions with score 3-5 on Prostate Imaging Reporting and Data System (PIRADS). Screening and biopsy guidance using an imaging modality with high accuracy could reduce the number of unnecessary biopsies, reducing side effects. The aim of this study was to assess the performance of positron emission tomography/MRI with Ga-68-labeled prostate-specific membrane antigen (PSMA-PET/MRI) to detect and localize primary sigPCa (ISUP grade group 3 and/or cancer core length >= 6 mm) and guide biopsy. Methods Prospective, open-label, single-center, non-randomized, diagnostic accuracy study including patients with suspected PCa by elevation of prostate-specific antigen (PSA) level and a suspicious lesion (PIRADS >= 3) on multiparametric MRI (mpMRI). Forty-two patients underwent PSMA-PET/MRI followed by both PSMA-PET/MRI-guided and section-based saturation template biopsy between May 2017 and February 2019. Primary outcome was the accuracy of PSMA-PET/MRI for biopsy guidance using section-based saturation template biopsy as the reference standard. Results SigPCa was found in 62% of the patients. Patient-based sensitivity, specificity, negative and positive predictive value, and accuracy for sigPCa were 96%, 81%, 93%, 89%, and 90%, respectively. One patient had PSMA-negative sigPCa. Eight of nine false-positive lesions corresponded to cancer on prostatectomy and one in six false-negative lesions was negative on prostatectomy. Conclusion PSMA-PET/MRI has a high accuracy for detecting sigPCa and is a promising tool to select patients with suspicion of PCa for biopsy.
- 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.
- A prospective cross-sectional study estimated glomerular filtration rate from creatinine and cystatin C in adults with solid tumors(2022) SILVA, Veronica T. Costa e; JR, Luiz A. Gil; INKER, Lesley A.; CAIRES, Renato A.; COSTALONGA, Elerson; COURA-FILHO, George; SAPIENZA, Marcelo T.; JR, Gilberto Castro; ESTEVEZ-DIZ, Maria Dp; ZANETTA, Dirce Maria T.; ANTONANGELO, Leila; MARCAL, Lia; TIGHIOUART, Hocine; MIAO, Shiyuan; MATHEW, Paul; LEVEY, Andrew S.; BURDMANN, Emmanuel A.Current guidelines recommend estimating glomerular filtration rate (eGFR) using creatinine (eGFRcr) with the Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) equation as the first test for GFR evaluation, but the Cockcroft-Gault (CG) equation is still commonly used in oncology practice and clinical trials despite increasing evidence of its inaccuracy compared to measured GFR (mGFR). Guidelines recommend eGFR using cystatin C (eGFRcys) or both markers (eGFRcr-cys) as a confirmatory test, but neither was carefully evaluated in cancer patients. Therefore, we compared performance of the CKD-EPI equations and others to the CG equation in adults with a variety of solid tumors. The mGFR was determined by plasma clearance of Cr-51-EDTA. Bias was defined as the median of the differences between mGFR and eGFR while accuracy was defined as the percentage of estimates that differed by more than 30% from the measured GFR (1-P30). We prospectively recruited 1,200 patients between April 2015 and September 2017 with a mean age and mGFR of 58.8 years and 78.4 ml/min/1.73m 2 , respectively. Bias among eGFRcr equations varied from -8.1 to +6.1 ml/min/1.73 m(2). CG was the least accurate, 1-P30 (95% confidence interval) was 24.9 (22.4- 27.3)%; CKD-EPI had 1-P30 of 19.1 (16.8-21.2)% while eGFRcr-cys had the best performance: bias -2.0 (-2.6 to -1.1) ml/min/1.73m(2) and 1-P30 7.8 (6.3-9.4)%. Thus, the CG equation should not be preferred over CKD-EPI equation, and eGFRcr-cys can be used as a confirmatory test in adults with solid tumors. Hence, a major policy implication would be to adopt general practice guideline-recommended methods for GFR evaluation in oncology practice and clinical trials.
- Influence on voxel-based dosimetry: noise effect on absorbed dose dosimetry at single time-point versus sequential single-photon emission computed tomography(2023) FONDA, Uysha de S.; LEITAO, Andre L. A.; PAIVA, Marcia M. D. P.; WILLEGAIGNON, Jose; JOSEFSSON, Anders; BUCHPIGUEL, Carlos A.; SAPIENZA, Marcelo T.ObjectiveThe purpose of this study was to evaluate how statistical fluctuation in single-photon emission computed tomography (SPECT) images propagate to absorbed dose maps. MethodsSPECT/computed tomography (CT) images of iodine-131 filled phantoms, using different acquisition and processing protocols, were evaluated using STRATOS software to assess the absorbed dose distribution at the voxel level. Absorbed dose values and coefficient of variation (COV) were analyzed for dosimetry based on single time-point SPECT images and time-integrated activities of SPECT sequences with low and high counts. ResultsConsidering dosimetry based on a single time-point, the mean absorbed dose was not significantly affected by total counts or reconstruction parameters, but the uniformity of the absorbed dose maps had an almost linear correlation with SPECT noise. When high- and low-count SPECT sequences were used to generate an absorbed dose map, the absorbed dose COV for each of the temporal sequences was slightly lower than the absorbed dose COV based on the single SPECT image with the highest count included in the sequence. ConclusionThe impact of changes in SPECT counts and reconstruction parameters is almost linear when dosimetry is based on isolated SPECT images, but less pronounced when dosimetry is based on sequential SPECTs.
- Ga-68-PSMA-11 PET/MRI versus multiparametric MRI in men referred for prostate biopsy: primary tumour localization and interreader agreement(2022) FERRARO, Daniela A.; HOETKER, Andreas M.; BECKER, Anton S.; MEBERT, Iliana; LAUDICELLA, Riccardo; BALTENSPERGER, Anka; RUPP, Niels J.; RUESCHOFF, Jan H.; MUELLER, Julian; MORTEZAVI, Ashkan; SAPIENZA, Marcelo T.; EBERLI, Daniel; DONATI, Olivio F.; BURGER, Irene A.Background Magnetic resonance imaging (MRI) is recommended by the European Urology Association guidelines as the standard modality for imaging-guided biopsy. Recently positron emission tomography with prostate-specific membrane antigen (PSMA PET) has shown promising results as a tool for this purpose. The aim of this study was to compare the accuracy of positron emission tomography with prostate-specific membrane antigen/magnetic resonance imaging (PET/MRI) using the gallium-labeled prostate-specific membrane antigen (Ga-68-PSMA-11) and multiparametric MRI (mpMRI) for pre-biopsy tumour localization and interreader agreement for visual and semiquantitative analysis. Semiquantitative parameters included apparent diffusion coefficient (ADC) and maximum lesion diameter for mpMRI and standardized uptake value (SUVmax) and PSMA-positive volume (PSMA(vol)) for PSMA PET/MRI. Results Sensitivity and specificity were 61.4% and 92.9% for mpMRI and 66.7% and 92.9% for PSMA PET/MRI for reader one, respectively. RPE was available in 23 patients and 41 of 47 quadrants with discrepant findings. Based on RPE results, the specificity for both imaging modalities increased to 98% and 99%, and the sensitivity improved to 63.9% and 72.1% for mpMRI and PSMA PET/MRI, respectively. Both modalities yielded a substantial interreader agreement for primary tumour localization (mpMRI kappa = 0.65 (0.52-0.79), PSMA PET/MRI kappa = 0.73 (0.61-0.84)). ICC for SUVmax, PSMA(vol) and lesion diameter were almost perfect (>= 0.90) while for ADC it was only moderate (ICC = 0.54 (0.04-0.78)). ADC and lesion diameter did not correlate significantly with Gleason score (rho = 0.26 and rho = 0.16) while SUVmax and PSMA(vol) did (rho = - 0.474 and rho = - 0.468). Conclusions PSMA PET/MRI has similar accuracy and reliability to mpMRI regarding primary prostate cancer (PCa) localization. In our cohort, semiquantitative parameters from PSMA PET/MRI correlated with tumour grade and were more reliable than the ones from mpMRI.
- Accuracy in dosimetry of diagnostic agents: impact of the number of source tissues used in whole organ S value-based calculations(2020) JOSEFSSON, Anders; SIRITANTIKORN, Klaikangwol; RANKA, Sagar; CARVALHO, Jose Willegaignon de Amorim de; BUCHPIGUEL, Carlos Alberto; SAPIENZA, Marcelo Tatit; BOLCH, Wesley E.; SGOUROS, GeorgeBackground Dosimetry for diagnostic agents is performed to assess the risk of radiation detriment (e.g., cancer) associated with the imaging agent and the risk is assessed by computing the effective dose coefficient, e. Stylized phantoms created by the MIRD Committee and updated by work performed by Cristy-Eckerman (CE) have been the standard in diagnostic dosimetry. Recently, the ICRP developed voxelized phantoms, which are described in ICRP Publication 110. These voxelized phantoms are more realistic and detailed in describing human anatomy compared with the CE stylized phantoms. Ideally, all tissues should be represented and their pharmacokinetics collected for an as accurate a dosimetric calculation as possible. As the number of source tissues included increases, the calculated e becomes more accurate. There is, however, a trade-off between the number of source tissues considered, and the time and effort required to measure the time-activity curve for each tissue needed for the calculations. In this study, we used a previously published Ga-68-DOTA-TATE data set to examine how the number of source tissues included for both the ICRP voxelized and CE stylized phantoms affected e. Results Depending upon the number of source tissues included e varied between 14.0-23.5 mu Sv/MBq for the ICRP voxelized and 12.4-27.7 mu Sv/MBq for the CE stylized phantoms. Furthermore, stability in e, defined as a < 10% difference between e obtained using all source tissues compared to one using fewer source tissues, was obtained after including 5 (36%) of the 14 source tissues for the ICRP voxelized, and after including 3 (25%) of the 12 source tissues for the CE stylized phantoms. In addition, a 2-fold increase in e was obtained when all source tissues where included in the calculation compared to when the TIAC distribution was lumped into a single reminder-of-body source term. Conclusions This study shows the importance of including the larger tissues like the muscles and remainder-of-body in the dosimetric calculations. The range of e based on the included tissues were less for the ICRP voxelized phantoms using tissue weighting factors from ICRP Publication 103 compared to CE stylized phantoms using tissue weighting factors from ICRP Publication 60.
conferenceObject Uncertainty in Reference Phantom-Based Dosimetry Calculations: Impact of Number of Source Organs(2019) JOSEFSSON, A.; SIRITANTIKORN, J. J.; SAPIENZA, M. Tatit; BOLCH, W. E.; SGOUROS, G.- A Prospective Cross-Sectional Study on the Performance of the 2021 CKD-EPI Equations Without Race in a Multiracial Population of Adults With Solid Tumors in Brazil(2023) SILVA, Veronica T. Costa e; JR, Luiz A. Gil; INKER, Lesley A.; CAIRES, Renato A.; COSTALONGA, Elerson; COURA-FILHO, George; SAPIENZA, Marcelo T.; JR, Gilberto Castro; ESTEVEZ-DIZ, Maria D. P.; ZANETTA, Dirce Maria T.; ANTONANGELO, Leila; MARCAL, Lia; TIGHIOUART, Hocine; MIAO, Shiyuan; MATHEW, Paul; LEVEY, Andrew S.; BURDMANN, Emmanuel A.
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