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1.
Lymphology ; 55(1): 1-9, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35896110

RESUMO

Lymphoscintigraphy with single-photon emission computed tomography (SPECT-CT) is useful in diagnosing lymphedema. However, there are multiple timings, techniques, and tracers utilized worldwide without any comparison. We examined and compared the image clarity with two different radiotracers, 99mTc human serum albumin (HSA) and 99mTc phytate (phytate), in the same patients. The study retrospectivity examined 46 limbs of 36 patients who underwent lymphoscintigraphy using HSA and phytate from January 2013 to September 2018. Tracer accumulation in the lymph nodes, linear pattern (LP), and dermal backflow (DBF) were qualitatively analyzed; contrast-to-noise ratios (CNR) of DBF and standardized uptake value ratio (SUVR) of LP were also quantitatively analyzed. Neither lymph node accumulation nor DBF identification showed significant difference. However, a significant difference was observed between the LP identification of the unaffected (p<0.001) and affected sides (p<0.001). On quantitative evaluation, CNR and SUVR of LP was significantly higher with HSA than with phytate (p<0.001). SUVR of LP was also significantly higher with HSA than with phytate in both unaffected (p=0.002) and affected (p=0.005) sides. Overall, images acquired with HSA were clearer than that with phytate, and the identification of LP was particularly better with HSA than with phytate. Thus, lymphoscintigraphy using HSA is preferred over phytate for both diagnosis and evaluation of disease severity and surgical site selection.


Assuntos
Linfedema , Linfocintigrafia , Humanos , Extremidade Inferior , Linfedema/diagnóstico por imagem , Ácido Fítico , Agregado de Albumina Marcado com Tecnécio Tc 99m , Tomografia Computadorizada de Emissão de Fóton Único , Tomografia Computadorizada por Raios X
2.
Molecules ; 27(13)2022 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-35807243

RESUMO

Technetium-99m macroaggregated albumin ([99mTc]Tc-MAA) is an injectable radiopharmaceutical used in nuclear medicine for lung perfusion scintigraphy. After changing to a new batch of macroaggregated albumin (MAA), we saw unwanted uptake in the liver and spleen. The batch was therefore tested by both the supplier and us and we found it to comply with the requirements of the European Pharmacopoeia (Ph. Eur.). However, a simple comparison between the problematic batch and a batch supplied by another manufacturer showed that there was a significant difference. The quality testing showed a higher number of small particles in the problem encumbered MAA batch with unwanted in vivo uptake. In this article we present a simple method of testing for particle size of [99mTc]Tc-MAA, which gives a good indication of how the radioactive drug performs in vivo. We argue that the quality control method described in the Ph. Eur. should be changed. The changes will improve concordance between the laboratory analyzes and what is seen in vivo in human lung perfusion scintigraphy. Furthermore, we hope that the MAA suppliers without delay will replace their release procedure to be in accordance with the method described in this article.


Assuntos
Compostos Radiofarmacêuticos , Agregado de Albumina Marcado com Tecnécio Tc 99m , Albuminas , Humanos , Pulmão , Controle de Qualidade
3.
Clin Nucl Med ; 47(9): 774-780, 2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-35713891

RESUMO

RATIONALE: In muscle-invasive bladder cancer (MIBC), lymph node invasion has proven to be an independent predictor of disease recurrence and cancer-specific survival. We evaluated the feasibility of targeting the sentinel node (SN) for biopsy in MIBC patients using the hybrid tracer indocyanine green (ICG)- 99m Tc-nanocolloid for simultaneous radioguidance and fluorescence guidance. METHODS: Twenty histologically confirmed cN0M0 MIBC patients (mean age, 63.3 years; range, 30-82 years), scheduled for radical cystectomy with SN biopsy and extended pelvic lymph node dissection (ePLND), were prospectively included. Twelve patients were operated on following neoadjuvant chemotherapy. The patients received lymphoscintigraphy as well as SPECT/CT after 4 transurethral injections of ICG- 99m Tc-nanocolloid (mean, 208 MBq; range, 172-229 MBq) around the tumor/scar in the detrusor muscle of the bladder on the day before radical cystectomy. Sentinel node resection was performed under radioguidance and fluorescence guidance. RESULTS: Nineteen patients could be analyzed. On preoperative imaging, SNs could be identified in 10 patients (53%; mean, 1.6 SN/patient), which revealed drainage pathways outside the ePLND in 20% of the patients. Interesting to note is that 2 patients (10%) with preoperative nonvisualization displayed fluorescent and radioactive SNs during surgery. Location of the primary tumor near the left lateral side of the bladder seemed to be a factor for nonvisualization. Nodal harvesting with ePLND varied among patients (mean, 23.3). Histopathology confirmed tumor-positive nodes in 4 (21%) of all patients. In the 2 patients where an SN could be identified, the ePLND specimens were tumor-negative. All patients with tumor-positive nodes had advanced disease (stage III). CONCLUSION: Sentinel node biopsy in bladder cancer using the hybrid tracer ICG- 99m Tc-nanocolloid is feasible, and preoperative imaging is predictive for the ability to perform SN biopsy in 83% of the patients who displayed an SN. In patients with a successful preoperative SN mapping using lymphoscintigraphy and SPECT/CT, the intraoperative SN guidance and detection were effective, even outside the ePLND area. As such, this study underscores the critical role that preoperative imaging plays in challenging image-guided surgery applications.


Assuntos
Linfonodo Sentinela , Neoplasias da Bexiga Urinária , Coloides , Humanos , Verde de Indocianina , Pessoa de Meia-Idade , Nanoestruturas , Projetos Piloto , Estudos Prospectivos , Linfonodo Sentinela/diagnóstico por imagem , Biópsia de Linfonodo Sentinela/métodos , Tecnécio , Agregado de Albumina Marcado com Tecnécio Tc 99m , Neoplasias da Bexiga Urinária/diagnóstico por imagem
4.
Diagn Interv Radiol ; 28(2): 156-165, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35548900

RESUMO

PURPOSE We aimed to evaluate whether the perfusion pattern from pretreatment hepatic artery perfusion scintigraphy (HAPS) in patients with liver malignancies can predict response to selective internal radiation therapy (SIRT). METHODS This retrospective study analyzed 152 consecutive patients treated with yttrium-90 (90Y) resin microspheres between April 2015 and July 2017. HAPS using single-photon emission computed tomography/computed tomography (SPECT/CT) with 99mtechnetium macroaggregated albumin (99mTc-MAA) was performed before SIRT. Investigators visually classified perfusion patterns of tumors as heterogeneous or diffuse in HAPS. Between diffuse and heterogeneous pattern group, positron emission tomography/computed tomography (PET/CT) and magnetic resonance imaging (MRI) were performed in third and sixth month after SIRT, and tumor response assessed and compared by using RECIST 1.1 or mRECIST. Overall survival (OS) and progression-free survival (PFS) were also compared with Kaplan-Meier/log-rank analyses. RESULTS Of 216 SIRT procedures, 172 were classified as heterogeneous and 44 as diffuse. Diffuse 99mTc- MAA uptake was associated with longer median OS than heterogeneous (22.2 vs. 14.4 months, respectively; P = .047). Subsegmental infusion was associated with longer OS than either lobar or segmental infusion (P = .090). Mean estimated OS was longer in patients with hepatocellular carcinoma (HCC) (34.2 months) than with colorectal carcinoma (CRC) (16.4 months) (P = .044). Patients with both diffuse and heterogeneous patterns were able to show complete response after SIRT. No statistically significant differences were observed between perfusion patterns and PFS or response rates to SIRT. CONCLUSION Although tumor perfusion patterns from preplanning HAPS analyses are useful for estimating tumor uptake of 90Y, they may not reliably predict hepatic treatment response, as patients with different perfusion patterns can show clinical response to SIRT.


Assuntos
Carcinoma Hepatocelular , Embolização Terapêutica , Neoplasias Hepáticas , Sirtuínas , Carcinoma Hepatocelular/diagnóstico por imagem , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/radioterapia , Embolização Terapêutica/métodos , Artéria Hepática/diagnóstico por imagem , Humanos , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/radioterapia , Microesferas , Imagem de Perfusão , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos , Estudos Retrospectivos , Agregado de Albumina Marcado com Tecnécio Tc 99m , Tomografia Computadorizada de Emissão de Fóton Único , Radioisótopos de Ítrio/uso terapêutico
5.
Phys Med ; 98: 98-112, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35526374

RESUMO

INTRODUCTION: In Selective Internal Radiation Therapy (SIRT), 90Y is administered to primary/secondary hepatic lesions. An accurate pre-treatment planning using 99mTc-MAA SPECT/CT allows the assessment of its feasibility and of the activity to be injected. Unfortunately, SPECT/CT suffers from patient-specific respiratory motion which causes artifacts and absorbed dose inaccuracies. In this study, a data-driven solution was developed to correct the respiratory motion. METHODS: The tool realigns the barycenter of SPECT projection images and shifts them to obtain a fine registration with the attenuation map. The tool was validated using a modified dynamic phantom with several breathing patterns. We compared the absorbed dose distributions derived from uncorrected(Dm)/corrected(Dc) images with static ones(Ds) in terms of γ-passing rates, 210 Gy isodose volumes, dose-volume histograms and percentage differences of mean doses (i.e., ΔD¯m and ΔD¯c, respectively). The tool was applied to twelve SIRT patients and the Bland-Altman analysis was performed on mean doses. RESULTS: In the phantom study, the agreement between Dc and Ds was higher (γ-passing rates generally > 90%) than Dm and Ds. The isodose volumes in Dc were closer than Dm to Ds, with differences up to 10% and 30% respectively. A reduction from a median ΔD¯m = -19.3% to ΔD¯c = -0.9%, from ΔD¯m = -42.8% to ΔD¯c = -7.0% and from ΔD¯m = 1586% to ΔD¯c = 47.2% was observed in liver-, tumor- and lungs-like structures. The Bland-Altman analysis on patients showed variations (±50 Gy) and (±4 Gy) between D¯c and D¯m of tumor and lungs, respectively. CONCLUSION: The proposed tool allowed the correction of 99mTc-MAA SPECT/CT images, improving the accuracy of the absorbed dose distribution.


Assuntos
Neoplasias Hepáticas , Radioterapia , Embolização Terapêutica , Humanos , Neoplasias Hepáticas/radioterapia , Microesferas , Radioterapia/métodos , Tomografia Computadorizada com Tomografia Computadorizada de Emissão de Fóton Único , Agregado de Albumina Marcado com Tecnécio Tc 99m/uso terapêutico , Tomografia Computadorizada de Emissão de Fóton Único , Radioisótopos de Ítrio/uso terapêutico
6.
Nucl Med Commun ; 43(6): 687-693, 2022 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-35437294

RESUMO

PURPOSE: Explore the application value of pulmonary perfusion imaging and delayed imaging for evaluating pulmonary capillary permeability. MATERIALS AND METHODS: After establishing a rat model of pulmonary contusion, changes in the metabolic index of technetium-99m macroaggregated albumin (99mTC-MAA) in the lungs of model rats were evaluated for two consecutive days. 99mTC-MAA metabolic indices of rat lungs with pulmonary contusion of varying severity (mild, moderate, and severe) were correlated with lung wet/dry weight ratio (W/D) and Evans blue extravasation. Finally, the method was validated in patients with pulmonary contusion and one healthy volunteer. RESULTS: The 99mTC-MAA metabolic index was 23.56% ± 2.44% in healthy control (HC) rat lung, 8.56% ± 3.42% immediately after lung contusion (d0), 8.35% ± 3.20% after 1 day (d1), and 17.45% ± 6.44% after 2 days (d2); indices at d0 and d1 were significantly higher than those at HC (P < 0.05). The metabolic index of 99mTC-MAA in lung had significant negative correlations with W/D (r = -0.8025; P = 0.0092) and Evans blue extravasation (r = -0.9356; P = 0.0002). Metabolic and oxygenation indices of 99mTC-MAA exhibited a significant positive linear correlation in patients with pulmonary contusion (r = 0.8925; P = 0.0416). CONCLUSION: Pulmonary perfusion and delayed imaging of 99mTC-MAA have potential value for evaluating pulmonary capillary permeability.


Assuntos
Contusões , Agregado de Albumina Marcado com Tecnécio Tc 99m , Animais , Permeabilidade Capilar , Contusões/diagnóstico por imagem , Azul Evans , Humanos , Pulmão/irrigação sanguínea , Pulmão/diagnóstico por imagem , Imagem de Perfusão/métodos , Ratos
7.
Curr Oncol ; 29(4): 2422-2434, 2022 03 29.
Artigo em Inglês | MEDLINE | ID: mdl-35448170

RESUMO

Selective internal radiation therapy (SIRT) is part of the treatment strategy for hepatocellular carcinoma (HCC). Strong clinical data demonstrated the effectiveness of this therapy in HCC with a significant improvement in patient outcomes. Recent studies demonstrated a strong correlation between the tumor response and the patient outcome when the tumor-absorbed dose was assessed by nuclear medicine imaging. Dosimetry plays a key role in predicting the clinical response and can be optimized using a personalized method of activity planning (multi-compartmental dosimetry). This paper reviews the main clinical results of SIRT in HCC and emphasizes the central role of dosimetry for improving it effectiveness. Moreover, some patient and tumor characteristics predict a worse outcome, and toxicity related to SIRT treatment of advanced HCC patient selection based on the performance status, liver function, tumor characteristics, and tumor targeting using technetium-99m macro-aggregated albumin scintigraphy can significantly improve the clinical performance of SIRT.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Sirtuínas , Carcinoma Hepatocelular/radioterapia , Humanos , Neoplasias Hepáticas/radioterapia , Microesferas , Seleção de Pacientes , Agregado de Albumina Marcado com Tecnécio Tc 99m , Resultado do Tratamento , Radioisótopos de Ítrio/uso terapêutico
8.
Phys Med Biol ; 67(11)2022 05 16.
Artigo em Inglês | MEDLINE | ID: mdl-35477100

RESUMO

Objective.The direct Monte Carlo (MC) simulation of radiation transport exploiting morphological and functional tomographic imaging as input data is considered the gold standard for internal dosimetry in nuclear medicine, and it is increasingly used in studies regarding trans-arterial radio-embolization (TARE). However, artefacts affecting the functional scans, such as reconstruction artefacts and motion blurring, decrease the accuracy in defining the radionuclide distribution in the simulations and consequently lead to errors in absorbed dose estimations. In this study, the relevance of such artefacts in patient-specific three-dimensional MC dosimetry was investigated in three cases of90Y TARE.Approach.The pre-therapy99mTc MacroAggregate Albumin (Tc-MAA) SPECTs and CTs of patients were used as input for simulations performed with the GEANT4-based toolkit GATE. Several pre-simulation SPECT-masking techniques were implemented, with the aim of zeroing the decay probability in air, in lungs, or in the whole volume outside the liver.Main results.Increments in absorbed dose up to about +40% with respect to the native-SPECT simulations were found in liver-related volumes of interest (VOIs), depending on the masking procedure adopted. Regarding lungs-related VOIs, decrements in absorbed doses in right lung as high as -90% were retrieved.Significance.These results highlight the relevant influence of SPECT artefacts, if not properly treated, on dosimetric outcomes for90Y TARE cases. Well-designed SPECT-masking techniques appear to be a promising way to correct for such misestimations.


Assuntos
Neoplasias Hepáticas , Radioisótopos de Ítrio , Albuminas , Artefatos , Humanos , Microesferas , Radiometria/métodos , Agregado de Albumina Marcado com Tecnécio Tc 99m , Tomografia Computadorizada de Emissão de Fóton Único , Radioisótopos de Ítrio/uso terapêutico
9.
Cardiovasc Intervent Radiol ; 45(7): 958-969, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35459960

RESUMO

PURPOSE: To determine how particle density affects dose distribution and outcomes after lobar radioembolization. METHODS: Matched pairs of patients, treated with glass versus resin microspheres, were selected by propensity score matching (114 patients), in this single-institution retrospective study. For each patient, tumor and liver particle density (particles/cm3) and dose (Gy) were determined. Tumor-to-normal ratio was measured on both 99mTc-MAA SPECT/CT and post-90Y bremsstrahlung SPECT/CT. Microdosimetry simulations were used to calculate first percentile dose, which is the dose in the cold spots between microspheres. Local progression-free survival (LPFS) and overall survival were analyzed. RESULTS: As more particles were delivered, doses on 90Y SPECT/CT became more uniform throughout the treatment volume: tumor and liver doses became more similar (p = 0.04), and microscopic cold spots between particles disappeared. For hypervascular tumors (tumor-to-normal ratio ≥ 2.6 on MAA scan), delivering fewer particles (< 6000 particles/cm3 treatment volume) was associated with better LPFS (p = 0.03). For less vascular tumors (tumor-to-normal ratio < 2.6), delivering more particles (≥ 6000 particles/cm3) was associated with better LPFS (p = 0.02). In matched pairs of patients, using the optimal particle density resulted in improved overall survival (11.5 vs. 6.8 months, p = 0.047), compared to using suboptimal particle density. Microdosimetry resulted in better predictions of LPFS (p = 0.03), and overall survival (p = 0.02), compared to conventional dosimetry. CONCLUSION: The number of particles delivered can be chosen to maximize the tumor dose and minimize the liver dose, based on tumor vascularity. Optimizing the particle density resulted in improved LPFS and overall survival.


Assuntos
Carcinoma Hepatocelular , Embolização Terapêutica , Neoplasias Hepáticas , Carcinoma Hepatocelular/diagnóstico por imagem , Carcinoma Hepatocelular/radioterapia , Embolização Terapêutica/métodos , Humanos , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/radioterapia , Microesferas , Estudos Retrospectivos , Agregado de Albumina Marcado com Tecnécio Tc 99m , Tomografia Computadorizada de Emissão de Fóton Único , Radioisótopos de Ítrio/uso terapêutico
10.
In Vivo ; 36(3): 1523-1526, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35478155

RESUMO

BACKGROUND/AIM: This is a report of the first clinical implementation of 99mTc-labeled diethylene triamine pentaacetate-galactosyl human serum albumin (99mTc-GSA) single-photon emission computed tomography (SPECT) image-guided inverse planning into palliative radiotherapy (RT) for diffuse liver metastases. CASE REPORT: A 48-year-old man developed chemo-refractory diffuse liver metastases from thymic carcinoma characterized by abdominal pain and distension. Palliative RT was performed with a total dose of 20 Gy in five fractions using double arc volumetric modulated arc therapy to reduce the dose to functional liver defined by 99mTc-GSA SPECT images. His symptoms were immediately relieved after RT and did not experience radiation-induced liver disease. Both Functional Assessment of Cancer Therapy (FACT)-G and FACT-Hep total scores improved after 2 weeks of RT initiation and did not become worse than baseline scores. CONCLUSION: The 99mTc-GSA SPECT image-guided palliative RT is an effective and safe treatment for patients with diffuse liver metastases.


Assuntos
Neoplasias Hepáticas , Compostos Radiofarmacêuticos , Humanos , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/radioterapia , Neoplasias Hepáticas/secundário , Masculino , Pessoa de Meia-Idade , Agregado de Albumina Marcado com Tecnécio Tc 99m , Pentetato de Tecnécio Tc 99m , Tomografia Computadorizada de Emissão de Fóton Único
11.
Clin Nucl Med ; 47(7): e515-e517, 2022 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-35353756

RESUMO

ABSTRACT: Gated tomographic radionuclide angiography can assess and monitor left cardiac function. Dedicated cardiac CZT cameras have enabled dose reduction and quicker acquisitions. New 3D-ring CZT general purpose systems are now available. We report 50 patients who underwent a 7-minute acquisition on a cardiac-dedicated CZT camera and 9 minutes on a new 3D-ring CZT system after mean injection of 321.4 ± 55.9 MBq 99mTc-labelled human serum albumin. There was no significant difference in left ventricular volumes, and left and right ventricular ejection fractions. These preliminary results seem to validate the use of 3D-ring CZT system for LEVF and cardiac function evaluation.


Assuntos
Câmaras gama , Imagem de Perfusão do Miocárdio , Imagem do Acúmulo Cardíaco de Comporta/métodos , Humanos , Agregado de Albumina Marcado com Tecnécio Tc 99m , Telúrio , Tomografia Computadorizada de Emissão de Fóton Único/métodos , Tomografia Computadorizada por Raios X , Zinco
12.
Clin Nucl Med ; 47(4): e366-e367, 2022 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-35143459

RESUMO

ABSTRACT: Arterial mapping and 99mTc-macroaggregated albumin (99mTc-MAA) hepatic perfusion imaging are routinely performed before 90Y radioembolization of hepatic tumors. These procedures serve multiple purposes, including an anatomical survey of hepatic arterial anatomy, interrogating expected microsphere distribution to avoid nontargeted embolization during therapy, and evaluating for possible hepatopulmonary shunting. We present a case where 99mTc-MAA planar images revealed unexpected soft tissue uptake within the left forearm, an unexpected complication that may result from residual 99mTc-MAA in the catheter being expelled as the catheter is removed, which is particularly important to avoid during the 90Y radioembolization procedure given the risk for associated radionecrosis.


Assuntos
Embolização Terapêutica , Neoplasias Hepáticas , Albuminas , Embolização Terapêutica/efeitos adversos , Embolização Terapêutica/métodos , Antebraço/diagnóstico por imagem , Humanos , Neoplasias Hepáticas/diagnóstico por imagem , Microesferas , Agregado de Albumina Marcado com Tecnécio Tc 99m , Radioisótopos de Ítrio
13.
Clin Nucl Med ; 47(3): e246-e248, 2022 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-35025793

RESUMO

ABSTRACT: A 54-year-old man with hepatocellular carcinoma from alcohol-induced cirrhosis presented with hepatic encephalopathy and refractory ascites related to decompensated liver disease. MRI confirmed disease progression adjacent the site of prior radiofrequency ablation, performed 2 years prior, with associated right hepatic vein tumor thrombus. 99mTc-labeled macroaggregated albumin lung shunt imaging performed before 90Y radioembolization identified a left lower lobe wedge-shaped defect, confirmed as pulmonary embolism on CT pulmonary angiography and MRI.


Assuntos
Carcinoma Hepatocelular , Embolização Terapêutica , Neoplasias Hepáticas , Embolia Pulmonar , Albuminas , Carcinoma Hepatocelular/diagnóstico por imagem , Carcinoma Hepatocelular/terapia , Embolização Terapêutica/efeitos adversos , Humanos , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/terapia , Pulmão/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Embolia Pulmonar/diagnóstico por imagem , Agregado de Albumina Marcado com Tecnécio Tc 99m , Radioisótopos de Ítrio
14.
AJR Am J Roentgenol ; 218(4): 728-737, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-34704460

RESUMO

BACKGROUND. Accurate assessment of hepatopulmonary shunting, typically performed by planar scintigraphy, is critical in planning 90Y radioembolization. High lung shunt fractions (LSFs) may alter treatment. OBJECTIVE. The purpose of this study is to compare LSFs calculated from planar scintigraphy versus SPECT/CT in patients with high planar LSFs (> 15%) and to describe the potential clinical and dosimetric implications of SPECT/CT LSF calculations. METHODS. This retrospective study included 36 patients (29 men and seven women; mean age, 62.4 ± 9.8 [SD] years) who underwent 99mTc-macroaggregated albumin (MAA) planar scintigraphy for planning hepatic radioembolization, had a planar LSF greater than 15%, and underwent concurrent SPECT/CT. Clinically reported planar LSFs were recorded. SPECT/CT LSFs were retrospectively calculated using automatically generated volumetric ROIs around the lungs and liver with subsequent manual adjustments. Total lung and perfused liver doses were calculated using a medical internal radiation dose model. Values derived from planar and SPECT/CT data were compared using Mann-Whitney U tests. Multivariable regression analysis was performed of factors associated with the discrepancy in LSF between the techniques. RESULTS. Mean planar LSF was 25.1% ± 11.6%, and mean SPECT/CT LSF was 16.0% ± 9.3% (p < .001). Mean lung dose was 18.8 ± 8.0 Gy for planar LSF versus 12.3 ± 7.2 Gy for SPECT/CT LSF (p < .001). Mean perfused liver dose was 92.9 ± 36.1 Gy using planar LSF versus 102.7 ± 39.1 Gy using SPECT/CT LSF (p < .001). In multivariable analysis, a larger discrepancy in LSF between planar scintigraphy and SPECT/CT was associated with a body mass index (weight in kilograms divided by the square of height in meters) of 26 or higher (p = .02), maximum tumor size of less than 9 cm (p = .05), and left hepatic intraarterial injection (p = .02). Fourteen of 36 patients did not undergo upfront radioembolization due to a planar LSF greater than 20% and instead underwent shunt-reducing embolization with subsequent radioembolization (n = 7), transarterial chemoembolization (n = 5), or no treatment (n = 2). Five of these 14 patients had a SPECT/CT LSF of less than 20% and would have been eligible for upfront radioembolization based on SPECT/CT LSF. Seven of 29 patients treated with radioembolization underwent prescribed dose reductions based on planar LSF; six of these patients would have qualified for standard radioembolization without dose reduction using SPECT/CT LSF. CONCLUSION. Planar scintigraphy yields greater LSFs compared with SPECT/CT, possibly leading to unnecessary shunt-reducing procedures and prescribed dose reductions. CLINICAL IMPACT. SPECT/CT should be considered for clinical LSF calculations before radioembolization in patients with high LSFs.


Assuntos
Carcinoma Hepatocelular , Quimioembolização Terapêutica , Embolização Terapêutica , Neoplasias Hepáticas , Idoso , Carcinoma Hepatocelular/patologia , Embolização Terapêutica/métodos , Feminino , Humanos , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/radioterapia , Pulmão/patologia , Masculino , Microesferas , Pessoa de Meia-Idade , Cintilografia , Estudos Retrospectivos , Agregado de Albumina Marcado com Tecnécio Tc 99m , Tomografia Computadorizada de Emissão de Fóton Único , Tomografia Computadorizada por Raios X , Radioisótopos de Ítrio/uso terapêutico
15.
J Biophotonics ; 15(1): e202100149, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34514735

RESUMO

The status of sentinel lymph nodes (SLNs) has a substantial prognostic value because these nodes are the first place where cancer cells accumulate along their spreading route. Routine SLN biopsy ("gold standard") involves peritumoral injections of radiopharmaceuticals, such as technetium-99m, which has obvious disadvantages. This review examines the methods used as "gold standard" analogs to diagnose SLNs. Nonradioactive preoperative and intraoperative methods of SLN detection are analyzed. Promising photonic tools for SLNs detection are reviewed, including NIR-I/NIR-II fluorescence imaging, photoswitching dyes for SLN detection, in vivo photoacoustic detection, imaging and biopsy of SLNs. Also are discussed methods of SLN detection by magnetic resonance imaging, ultrasonic imaging systems including as combined with photoacoustic imaging, and methods based on the magnetometer-aided detection of superparamagnetic nanoparticles. The advantages and disadvantages of nonradioactive SLN-detection methods are shown. The review concludes with prospects for the use of conservative diagnostic methods in combination with photonic tools.


Assuntos
Linfonodo Sentinela , Corantes , Meios de Contraste , Humanos , Verde de Indocianina , Linfonodos/diagnóstico por imagem , Metástase Linfática , Linfonodo Sentinela/diagnóstico por imagem , Biópsia de Linfonodo Sentinela , Agregado de Albumina Marcado com Tecnécio Tc 99m
16.
Clin Nucl Med ; 47(2): e201-e202, 2022 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-34507328

RESUMO

ABSTRACT: Selective internal radiation therapy (SIRT) is a catheter-guided treatment offered to selected patients with primary and secondary liver malignancies. SIRT is preceded by a workup procedure, where 99mTc-MAA (macroaggregated albumin) is injected in the tumor supplying artery/arteries followed by MAA scintigraphy. SIRT is frequently offered to patients with hepatocellular carcinoma (HCC), but large HCCs are known to be associated with a high risk of liver-to-lung shunting. We present a HCC patient case where a large lung-shunt enabled diagnosis of pulmonary embolism.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Embolia Pulmonar , Humanos , Achados Incidentais , Agregado de Albumina Marcado com Tecnécio Tc 99m , Radioisótopos de Ítrio
17.
Q J Nucl Med Mol Imaging ; 65(4): 353-370, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34881847

RESUMO

Primary and secondary hepatic tumors have a dramatic impact in oncology. Despite many advances in diagnosis and therapy, the management of hepatic malignancies is still challenging, ranging from various loco-regional approaches to system therapies. In this scenario, theragnostic approaches, based on the administration of a radiopharmaceuticals' pair, the first labeled with a radionuclide suitable for the diagnostic phase and the second one bound to radionuclide emitting particles for therapy, is gaining more and more importance. Selective internal radiation therapy (SIRT) with microspheres labeled with 90Y or 166Ho is widely used as a loco-regional treatment for primary and secondary hepatic tumors. While 166Ho presents both gamma and beta emission and can be therefore considered a real "theragnostic" agent, for 90Y-microspheres theragnostic approach is realized at the diagnostic phase through the utilization of macroaggregates of human albumin, labeled with 99mTc as "biosimilar" agent respect to microspheres. The aim of the present review was to cover theragnostic applications of 90Y/166Ho-labeled microspheres in clinical practice. Furthermore, we report the preliminary data concerning the potential role of some emerging theragnostic biomarkers for hepatocellular carcinoma, such as glypican-3 (GPC3) and prostate specific membrane antigen (PSMA).


Assuntos
Neoplasias Hepáticas , Radioisótopos de Ítrio , Glipicanas , Humanos , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/radioterapia , Masculino , Microesferas , Compostos Radiofarmacêuticos , Agregado de Albumina Marcado com Tecnécio Tc 99m , Tomografia Computadorizada de Emissão de Fóton Único , Radioisótopos de Ítrio/uso terapêutico
18.
Diagn Interv Radiol ; 27(6): 768-773, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34792032

RESUMO

PURPOSE: We aimed to determine whether antireflux (ARC) catheter may result in better tumor targeting in liver radioembolization using 90Y-resin microspheres. METHODS: Patients treated with resin microspheres for hepatocellular carcinoma (HCC) and secondary liver malignancies were retrospectively analyzed. All patients underwent a 99mTc-macroaggregated albumin (99mTc-MAA) single photon emission computed tomography (SPECT) following the planning arteriography with a conventional end-hole catheter. For 90Y-microspheres injection, two groups were defined depending on the type of catheter used: an ARC group (n=38) and a control group treated with a conventional end-hole catheter (n=23). 90Y positron emission tomography computed tomography (PET/CT) was performed after the therapeutic arteriography. The choice of the catheter was not randomized, but left to the choice of the interventional radiologist. 99mTc-MAA SPECT and 90Y PET/CT were co-registered with the baseline imaging to determine a tumor to normal liver ratio (T/NL[MAA or 90Y]) and tumor dose (TD[MAA or 90Y]) for the planning and therapy. RESULTS: Overall, 38 patients (115 lesions) and 23 patients (75 lesions) were analyzed in the ARC and control groups, respectively. In the ARC group, T/NL90Y and TD90Y were significantly higher than T/NLMAA and TDMAA. Median (IQR) T/NL90Y was 2.16 (2.15) versus 1.74 (1.43) for T/NLMAA (p < 0.001). Median (IQR) TD90Y was 90.96 Gy (98.31 Gy) versus 73.72 Gy (63.82 Gy) for TDMAA (p < 0.001). In this group, the differences were highly significant for neuroendocrine metastases (NEM) and HCC and less significant for colorectal metastases (CRM). In the control group, no significant differences were demonstrated. CONCLUSION: The use of an ARC significantly improves tumor deposition in liver radioembolization with resin microspheres.


Assuntos
Carcinoma Hepatocelular , Embolização Terapêutica , Neoplasias Hepáticas , Carcinoma Hepatocelular/diagnóstico por imagem , Carcinoma Hepatocelular/radioterapia , Cateteres , Humanos , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/radioterapia , Microesferas , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Estudos Retrospectivos , Agregado de Albumina Marcado com Tecnécio Tc 99m , Tomografia Computadorizada de Emissão de Fóton Único , Radioisótopos de Ítrio/uso terapêutico
19.
Radiol Technol ; 93(2): 197-215, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34728580

RESUMO

Radioembolization is used to treat hepatocellular carcinoma, a type of liver cancer, by introducing radioactive yttrium 90 (90Y) directly into the hepatic vasculature. This method allows for a high dose of radiation to be delivered to the cancer cells while sparing the surrounding healthy liver tissue. Radioembolization requires careful pretreatment planning to determine if administration of 90Y is a suitable and safe treatment option. Planning includes mapping angiograms to assess vascular structures and conjoint technetium Tc 99m macroaggregated albumin hepatic perfusion imaging to study blood flow to surrounding healthy tissue.


Assuntos
Carcinoma Hepatocelular , Embolização Terapêutica , Neoplasias Hepáticas , Carcinoma Hepatocelular/diagnóstico por imagem , Carcinoma Hepatocelular/radioterapia , Humanos , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/radioterapia , Compostos Radiofarmacêuticos , Estudos Retrospectivos , Agregado de Albumina Marcado com Tecnécio Tc 99m , Tomografia Computadorizada de Emissão de Fóton Único , Radioisótopos de Ítrio/uso terapêutico
20.
Med Phys ; 48(11): 7427-7438, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34628667

RESUMO

BACKGROUND: Radioembolization with 90 Y microspheres is a treatment approach for liver cancer. Currently, employed dosimetric calculations exhibit low accuracy, lacking consideration of individual patient, and tissue characteristics. PURPOSE: The purpose of the present study was to employ deep learning (DL) algorithms to differentiate patterns of pretreatment distribution of 99m Tc-macroaggregated albumin on SPECT/CT and post-treatment distribution of 90 Y microspheres on PET/CT and to accurately predict how the 90 Y-microspheres will be distributed in the liver tissue by radioembolization therapy. METHODS: Data for 19 patients with liver cancer (10 with hepatocellular carcinoma, 5 with intrahepatic cholangiocarcinoma, 4 with liver metastases) who underwent radioembolization with 90 Y microspheres were used for the DL training. We developed a 3D voxel-based variation of the Pix2Pix model, which is a special type of conditional GANs designed to perform image-to-image translation. SPECT and CT scans along with the clinical target volume for each patient were used as inputs, as were their corresponding post-treatment PET scans. The real and predicted absorbed PET doses for the tumor and the whole liver area were compared. Our model was evaluated using the leave-one-out method, and the dose calculations were measured using a tissue-specific dose voxel kernel. RESULTS: The comparison of the real and predicted PET/CT scans showed an average absorbed dose difference of 5.42% ± 19.31% and 0.44% ± 1.64% for the tumor and the liver area, respectively. The average absorbed dose differences were 7.98 ± 31.39 Gy and 0.03 ± 0.25 Gy for the tumor and the non-tumor liver parenchyma, respectively. Our model had a general tendency to underpredict the dosimetric results; the largest differences were noticed in one case, where the model underestimated the dose to the tumor area by 56.75% or 72.82 Gy. CONCLUSIONS: The proposed deep-learning-based pretreatment planning method for liver radioembolization accurately predicted 90 Y microsphere biodistribution. Its combination with a rapid and accurate 3D dosimetry method will render it clinically suitable and could improve patient-specific pretreatment planning.


Assuntos
Aprendizado Profundo , Embolização Terapêutica , Neoplasias Hepáticas , Humanos , Fígado/diagnóstico por imagem , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/radioterapia , Microesferas , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Agregado de Albumina Marcado com Tecnécio Tc 99m , Distribuição Tecidual , Tomografia Computadorizada de Emissão de Fóton Único , Radioisótopos de Ítrio/uso terapêutico
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