RESUMO
With the arrival of disease-modifying drugs, neurodegenerative diseases will require an accurate diagnosis for optimal treatment. Convolutional neural networks are powerful deep learning techniques that can provide great help to physicians in image analysis. The purpose of this study is to introduce and validate a 3D neural network for classification of Alzheimer's disease (AD), frontotemporal dementia (FTD) or cognitively normal (CN) subjects based on brain glucose metabolism. Retrospective [18F]-FDG-PET scans of 199 CE, 192 FTD and 200 CN subjects were collected from our local database, Alzheimer's disease and frontotemporal lobar degeneration neuroimaging initiatives. Training and test sets were created using randomization on a 90 %-10 % basis, and training of a 3D VGG16-like neural network was performed using data augmentation and cross-validation. Performance was compared to clinical interpretation by three specialists in the independent test set. Regions determining classification were identified in an occlusion experiment and Gradient-weighted Class Activation Mapping. Test set subjects were age- and sex-matched across categories. The model achieved an overall 89.8 % accuracy in predicting the class of test scans. Areas under the ROC curves were 93.3 % for AD, 95.3 % for FTD, and 99.9 % for CN. The physicians' consensus showed a 69.5 % accuracy, and there was substantial agreement between them (kappa = 0.61, 95 % CI: 0.49-0.73). To our knowledge, this is the first study to introduce a deep learning model able to discriminate AD and FTD based on [18F]-FDG PET scans, and to isolate CN subjects with excellent accuracy. These initial results are promising and hint at the potential for generalization to data from other centers.
Assuntos
Doença de Alzheimer , Demência Frontotemporal , Humanos , Doença de Alzheimer/diagnóstico por imagem , Fluordesoxiglucose F18 , Demência Frontotemporal/diagnóstico por imagem , Estudos Retrospectivos , Encéfalo/diagnóstico por imagem , Tomografia por Emissão de Pósitrons/métodos , Redes Neurais de ComputaçãoRESUMO
OBJECTIVES: New PET data-processing tools allow for automatic lesion selection and segmentation by a convolution neural network using artificial intelligence (AI) to obtain total metabolic tumor volume (TMTV) and total lesion glycolysis (TLG) routinely at the clinical workstation. Our objective was to evaluate an AI implemented in a new version of commercial software to verify reproducibility of results and time savings in a daily workflow. METHODS: Using the software to obtain TMTV and TLG, two nuclear physicians applied five methods to retrospectively analyze data for 51 patients. Methods 1 and 2 were fully automated with exclusion of lesions ≤ 0.5 mL and ≤ 0.1 mL, respectively. Methods 3 and 4 were fully automated with physician review. Method 5 was semi-automated and used as reference. Time and number of clicks to complete the measurement were recorded for each method. Inter-instrument and inter-observer variation was assessed by the intra-class coefficient (ICC) and Bland-Altman plots. RESULTS: Between methods 3 and 5, for the main user, the ICC was 0.99 for TMTV and 1.0 for TLG. Between the two users applying method 3, ICC was 0.97 for TMTV and 0.99 for TLG. Mean processing time (± standard deviation) was 20 s ± 9.0 for method 1, 178 s ± 125.7 for method 3, and 326 s ± 188.6 for method 5 (p < 0.05). CONCLUSION: AI-enabled lesion detection software offers an automated, fast, reliable, and consistently performing tool for obtaining TMTV and TLG in a daily workflow. KEY POINTS: ⢠Our study shows that artificial intelligence lesion detection software is an automated, fast, reliable, and consistently performing tool for obtaining total metabolic tumor volume and total lesion glycolysis in a daily workflow.
Assuntos
Fluordesoxiglucose F18 , Linfoma Difuso de Grandes Células B , Humanos , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos , Carga Tumoral , Inteligência Artificial , Estudos Retrospectivos , Reprodutibilidade dos Testes , Prognóstico , Linfoma Difuso de Grandes Células B/diagnóstico por imagem , Redes Neurais de Computação , GlicóliseRESUMO
As protein-losing enteropathy (PLE) can lead to hypogammaglobulinemia and lymphopenia, and since common variable immunodeficiency (CVID) is associated with digestive complications, we wondered if (1) PLE could occur during CVID and (2) specific features could help determine whether a patient with antibody deficiency has CVID, PLE, or both. Eligible patients were thus classified in 3 groups: CVID + PLE (n = 8), CVID-only (= 19), and PLE-only (n = 13). PLE was diagnosed using fecal clearance of α1-antitrypsin or 111In-labeled albumin. Immunoglobulin (Ig) A, G, and M, naive/memory B and T cell subsets were compared between each group. CVID + PLE patients had multiple causes of PLE: duodenal villous atrophy (5/8), nodular follicular hyperplasia (4/8), inflammatory bowel disease-like (4/8), portal hypertension (4/8), giardiasis (3/8), and pernicious anemia (1/8). Compared to the CVID-only group, CVID + PLE patients had similar serum Ig levels, B cell subset counts, but lower naive T cell proportion and IgG replacement efficiency index. Compared to the CVID-only group, PLE-only patients did not develop infections but had higher serum levels of IgG (p = 0.03), IgA (p < 0.0001), and switched memory B cells (p = 0.001); and decreased naive T cells (CD4+: p = 0.005; CD8+: p < 0.0001). Compared to the PLE-only group, CVID + PLE patients had higher infection rates (p = 0.0003), and lower serum Ig (especially IgA: p < 0.001) and switched memory B cells levels. In conclusion, PLE can occur during CVID and requires higher IgG replacement therapy dosage. PLE can also mimic CVID and is associated with milder immunological abnormalities, notably mildly decreased to normal serum IgA and switched memory B cell levels.
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Imunodeficiência de Variável Comum , Enteropatias Perdedoras de Proteínas , Humanos , Imunodeficiência de Variável Comum/complicações , Imunodeficiência de Variável Comum/diagnóstico , Enteropatias Perdedoras de Proteínas/etiologia , Enteropatias Perdedoras de Proteínas/complicações , Diagnóstico Diferencial , Imunoglobulina A , Imunoglobulina GRESUMO
BACKGROUND: Chemotherapy is increasingly used before hepatic resection, with controversial impact regarding liver function. This study aimed to assess the capacity of 99mTc-labelled-mebrofenin SPECT-hepatobiliary scintigraphy (HBS) to predict liver dysfunction due to chemotherapy and/or chemotherapeutic-associated liver injuries (CALI), such as sinusoidal obstruction syndrome (SOS) and nonalcoholic steatohepatitis (NASH) activity score (NAS). METHODS: From 2011 to 2015, all consecutive noncirrhotic patients scheduled for a major hepatectomy (≥ 3 segments) gave informed consent for preoperative SPECT-HBS allowing measurements of segmental liver function. As primary endpoint, HBS results were compared between patients with versus without (1) preoperative chemotherapy (≤ 3 months); and (2) CALI, mainly steatosis, NAS (Kleiner), or SOS (Rubbia-Brandt). Secondary endpoints were (1) other factors impairing function; and (2) impact of chemotherapy, and/or CALI on hepatocyte isolation outcome via liver tissues. RESULTS: Among 115 patients, 55 (47.8%) received chemotherapy. Sixteen developed SOS and 35 NAS, with worse postoperative outcome. Overall, chemotherapy had no impact on liver function, except above 12 cycles. In patients with CALI, a steatosis ≥ 30% significantly compromised function, as well as NAS, especially grades 2-5. Conversely, SOS had no impact, although subjected to very low patients number with severe SOS. Other factors impairing function were diabetes, overweight/obesity, or fibrosis. Similarly, chemotherapy in 73 of 164 patients had no effect on hepatocytes isolation outcome; regarding CALI, steatosis ≥ 30% and NAS impaired the yield and/or viability of hepatocytes, but not SOS. CONCLUSIONS: In this first large, prospective study, HBS appeared to be a valuable tool to select heavily treated patients at risk of liver dysfunction through steatosis or NAS.
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Neoplasias Colorretais , Neoplasias Hepáticas , Neoplasias Colorretais/cirurgia , Hepatectomia , Humanos , Fígado/diagnóstico por imagem , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/cirurgia , Estudos Prospectivos , Cintilografia , Tomografia Computadorizada de Emissão de Fóton ÚnicoRESUMO
BACKGROUND: The kinetics of remnant liver (RL) function is unknown after major hepatectomy (MH), especially in case of post-hepatectomy liver failure (PHLF). This study investigated the change in RL function after MH using 99mTc-labelled-mebrofenin SPECT-scintigraphy and its correlation with RL volume and PHLF. METHODS: From 2011 to 2015, 125 patients undergoing MH had volumetric assessment by CT and functional SPECT-scintigraphy preoperatively and at day 7 (POD7) and 1 month (1M). RL volume and function changes were compared in (i) overall population and (ii) 17 patients with vs. 42 without PHLF (ISGLS) matched on preoperative RL function. RESULTS: Increase in RL function correlated poorly with volume increase at POD7 (r = 0.035, p = 0.43) and 1M (r = 0.394, p < 0.0001). Overall, function increase on POD7 (+38.8%) was lower than volume (+49.4%), but comparable at 1M (+78.8% vs. +73%). PHLF patients showed lower function increase on POD7 (+2.1% [-89%-77.8%] vs. +50% [-39%-218%]; p = 0.006). At 1M, 4 PHLF patients died with no function increase despite significant volumetric gain. CONCLUSIONS: We first showed via sequential SPECT-scintigraphy that RL function increase after MH is slower than volume increase. A poor kinetic of function was correlated with PHLF as early as POD7, contrasting with substantial volume gain in PHLF patients.
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Hepatectomia , Falência Hepática , Humanos , Cinética , Falência Hepática/etiologia , Testes de Função HepáticaRESUMO
Associating Liver Partition and Portal Vein Ligation for Staged Hepatectomy (ALPPS) has emerged as an alternative for patients with bilobar colorectal liver metastasis deemed unresectable due to inadequate future remnant liver (FRL). Nevertheless, high morbidity and mortality rates have been reported. In this setting, including hepatobiliary scintigraphy in the clinical and surgical management of patients offered ALPPS has been advocated to both assess eligibility for ALPPS stagel and suitable time for ALPPS stage2. Recently, it was stated that partial ALPPS with a liver split restricted to 50% of the transection line (or up to the middle hepatic vein in case of right extended hepatectomy) and a shortened stagel allows improving the postoperative course without precluding the inter-stages FRL hypertrophy. We describe a case series of p-ALPPS with stagel performed laparoscopically, including sequential assessments of the FRL volumes and functions via pre-stagel and pre-stage2 computed tomography volumetry and HIDA SPECT-scintigraphy. In five patients, laparoscopic p-ALPPS was associated with rapid and significant gain of remnant functional volume - much better than previously observed for ALPPS - facilitating early stage2 without inflammatory adherences. In conclusion, laparoscopic p-ALPPS is feasible and seems less aggressive than the original ALPPS technique with total transection. It may be an interesting alternative to the classical portal vein embolization (PVE) and two-stage hepatectomy strategy.
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Neoplasias Colorretais/patologia , Hepatectomia/métodos , Laparoscopia/métodos , Laparotomia/métodos , Neoplasias Hepáticas/cirurgia , Veia Porta/cirurgia , Idoso , Feminino , Humanos , Ligadura , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/secundário , Masculino , Pessoa de Meia-Idade , Metástase Neoplásica , Veia Porta/diagnóstico por imagem , Tomografia Computadorizada de Emissão de Fóton Único , Tomografia Computadorizada por Raios XRESUMO
BACKGROUND & OBJECTIVES: Sarcopenia is a morbi-mortality risk factor in digestive surgery, though its impact after major hepatectomy (MH) remains unknown. This prospective pilot study investigated whether volume and function of a regenerating liver is influenced by body composition. METHODS: From 2011 to 2016, 125 consecutive patients had computed tomography and 99mTc-labelled-mebrofenin SPECT-scintigraphy before and after MH at day 7 and 1 month for measurements of liver volumes and functions. L3 vertebra muscle mass identified sarcopenia. Primary endpoint was the impact of sarcopenia on regeneration capacities (i.e. volume/function changes and post-hepatectomy liver failure (PHLF) rate). Secondary endpoint was 3-month morbi-mortality. RESULTS: Sarcopenic patients (SP; N = 69) were significantly older than non-sarcopenic (NSP), with lower BMI and more malignancies, but with comparable liver function/volume at baseline. Postoperatively, SP showed higher rates of ISGLS_PHLF (24.6 % vs 10.9 %; p = 0.05) but with comparable rates of severe morbidity (23.2 % vs 16.4 %; p = 0.35), overall (8.7 % vs 3.6 %; p = 0.3) and PHLF-related mortality (8,7 % vs 1.8 %; p = 0.075). After matching on the extent of resection or using propensity score, regeneration and PHLF rates were similar. CONCLUSION: This prospective study using first sequential SPECT-scintigraphy showed that sarcopenia by itself does not affect liver regeneration capacities and short-term postoperative course after MH.
Assuntos
Compostos de Anilina , Glicina , Hepatectomia , Regeneração Hepática , Sarcopenia , Tomografia Computadorizada de Emissão de Fóton Único , Tomografia Computadorizada por Raios X , Humanos , Sarcopenia/diagnóstico por imagem , Sarcopenia/etiologia , Sarcopenia/complicações , Estudos Prospectivos , Masculino , Feminino , Regeneração Hepática/fisiologia , Idoso , Pessoa de Meia-Idade , Projetos Piloto , Tamanho do Órgão , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/diagnóstico por imagem , Compostos Radiofarmacêuticos , Compostos de Organotecnécio , Iminoácidos , Falência Hepática/diagnóstico por imagem , Falência Hepática/etiologia , Falência Hepática/cirurgiaRESUMO
OBJECTIVE: To evaluate the role of ¹8F-fluorodeoxyglucose-positron emission tomography (FDG-PET) in the assessment of tumor response after the completion of neoadjuvant chemoradiation (CRT) in patients with locally advanced resectable esophageal cancer. BACKGROUND: After primary CRT, a noninvasive evaluation of the tumor response could help in the treatment decision to identify patients who may benefit from surgery. Whether FDG-PET provides clinically relevant information remains questionable. METHODS: Operable patients with locally advanced esophageal cancer (clinically staged T3 N0-1 M0) were enrolled in this prospective study. The complete treatment plan included neoadjuvant CRT (cisplatin + 5-fluorouracil/45 Gy) followed 6 to 8 weeks later by a transthoracic en bloc esophagectomy. Morphological evaluation combined with FDG-PET was performed 2 weeks before the start of CRT and 4 to 6 weeks after the completion of CRT. Intratumoral pre- and posttreatment FDG-standardized uptake values (SUV1, SUV2, percentage change) were assessed. These variables were correlated with pathological and morphologic responses and survival. Investigators were blinded to the FDG-PET results unless they revealed metastatic disease. RESULTS: Of 60 total patients, 46 underwent the complete treatment plan (median age: 60.1 years; adenocarcinoma: 25 patients; squamous cell cancer: 21 patients). A major pathological response occurred in 45.7% of patients and was associated with a favorable outcome (P = 0.057). Neoadjuvant CRT led to a significant reduction in intratumoral FDG-uptake (P < 0.001). No significant association was seen between a pathological response (either complete or major) and the FDG-PET results (P > 0.280). The SUV2 value was correlated with a morphological response and the possibility to perform an R0 resection (P < 0.018; receiver operating characteristic curve analysis: SUV2 threshold = 5.5). No significant association was found between metabolic imaging and recurrence or survival. CONCLUSIONS: FDG-PET does not effectively correlate with pathological response and long-term survival in patients with locally advanced esophageal cancer undergoing neoadjuvant CRT followed by surgery. (Registered on the www.e-cancer RECF0350.).
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Quimiorradioterapia , Neoplasias Esofágicas/diagnóstico por imagem , Neoplasias Esofágicas/terapia , Fluordesoxiglucose F18 , Tomografia por Emissão de Pósitrons/métodos , Compostos Radiofarmacêuticos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Cisplatino/administração & dosagem , Interpretação Estatística de Dados , Neoplasias Esofágicas/patologia , Esofagectomia/métodos , Feminino , Fluoruracila/administração & dosagem , Humanos , Masculino , Pessoa de Meia-Idade , Terapia Neoadjuvante , Estadiamento de Neoplasias , Resultado do TratamentoRESUMO
BACKGROUND: Cardiac uptake on technetium-99m whole-body scintigraphy (WBS) is almost pathognomonic of transthyretin cardiac amyloidosis. The rare false positives are often related to light-chain cardiac amyloidosis. However, this scintigraphic feature remains largely unknown, leading to misdiagnosis despite characteristic images. A retrospective review of all WBSs in a hospital database to detect those with cardiac uptake may allow the identification of undiagnosed patients. OBJECTIVES: The authors sought to develop and validate a deep learning-based model that automatically detects significant cardiac uptake (Perugini grade ≥2) on WBS from large hospital databases in order to retrieve patients at risk of cardiac amyloidosis. METHODS: The model is based on a convolutional neural network with image-level labels. The performance evaluation was performed with C-statistics using a 5-fold cross-validation scheme stratified so that the proportion of positive and negative WBSs remained constant across folds and using an external validation data set. RESULTS: The training data set consisted of 3,048 images: 281 positives (Perugini grade ≥2) and 2,767 negatives. The external validation data set consisted of 1,633 images: 102 positives and 1,531 negatives. The performance of the 5-fold cross-validation and external validation was as follows: 98.9% (± 1.0) and 96.1% for sensitivity, 99.5% (± 0.4) and 99.5% for specificity, and 0.999 (SD = 0.000) and 0.999 for the area under the curve of the receiver-operating characteristic curves. Sex, age <90 years, body mass index, injection-acquisition delay, radionuclides, and the indication of WBS only slightly affected performances. CONCLUSIONS: The authors' detection model is effective at identifying patients with cardiac uptake Perugini grade ≥2 on WBS and may help in the diagnosis of patients with cardiac amyloidosis.
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Amiloidose , Cardiomiopatias , Aprendizado Profundo , Humanos , Idoso de 80 Anos ou mais , Valor Preditivo dos Testes , Amiloidose/diagnóstico por imagem , Coração , Cintilografia , Cardiomiopatias/diagnóstico por imagemRESUMO
Metformin (MET) is the most prescribed antidiabetic drug, but its mechanisms of action remain elusive. Recent data point to the gut as MET's primary target. Here, we explored the effect of MET on the gut glucose transport machinery. Using human enterocytes (Caco-2/TC7 cells) in vitro, we showed that MET transiently reduced the apical density of sodium-glucose transporter 1 (SGLT1) and decreased the absorption of glucose, without changes in the mRNA levels of the transporter. Administered 1 h before a glucose challenge in rats (Wistar, GK), C57BL6 mice and mice pigs, oral MET reduced the post-prandial glucose response (PGR). This effect was abrogated in SGLT1-KO mice. MET also reduced the luminal clearance of 2-(18F)-fluoro-2-deoxy-D-glucose after oral administration in rats. In conclusion, oral metformin transiently lowers post-prandial glucose response by reducing the apical expression of SGLT1 in enterocytes, which may contribute to the clinical effects of the drug.
RESUMO
In order to explore pituitary adenoma (PA), magnetic resonance imaging (MRI) remains the cornerstone. However, there are some limitations and MRI can be non-conclusive. The development of additional imaging modalities like nuclear medicine explorations may help to confirm PA diagnosis, guide management and follow up. Nuclear medicine uses radiopharmaceuticals for imaging with single photon emission computed tomography (SPECT), or positron emission tomography (PET), coupled to CT scan. Radiopharmaceuticals products target specific cellular elements which allow to explore several biological pathways. Nuclear medicine may also be used for therapeutic purposes and recent developments of approach based on Peptide Receptor Radionuclide Therapy (PRRT) for treatment of aggressive PA and pituitary carcinoma will be reviewed. Several radiotracers have been studied in the context of PA, and the aim of this paper is to discuss their respective performances and clinical interest.
Assuntos
Medicina Nuclear , Neoplasias Hipofisárias , Humanos , Neoplasias Hipofisárias/diagnóstico por imagemAssuntos
Neoplasias da Vesícula Biliar/diagnóstico por imagem , Neoplasias da Vesícula Biliar/cirurgia , Hepatectomia/métodos , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/cirurgia , Fígado/irrigação sanguínea , Veia Porta/cirurgia , Tomografia Computadorizada de Emissão de Fóton Único/métodos , Idoso , Idoso de 80 Anos ou mais , Compostos de Anilina , Neoplasias Colorretais/patologia , Terapia Combinada , Embolização Terapêutica , Feminino , Neoplasias da Vesícula Biliar/mortalidade , Glicina , Hepatectomia/mortalidade , Humanos , Iminoácidos , Fígado/cirurgia , Testes de Função Hepática , Neoplasias Hepáticas/mortalidade , Neoplasias Hepáticas/secundário , Masculino , Pessoa de Meia-Idade , Compostos de Organotecnécio , Compostos Radiofarmacêuticos , Terapia de Salvação , Resultado do TratamentoRESUMO
BACKGROUND: Interstitial lung disease is a common complication of systemic sclerosis (SSc-ILD), and it remains difficult to accurately predict its course. Progressing ILD could be more metabolically active, suggesting that the 18F-FDG tracer could be a tool in the managing of SSc-ILD. METHODS: In our center, SSc patients and controls (non-Hodgkin lymphoma cured after first-line regimen) who had received a PET/CT were screened retrospectively. The FDG uptake (visual intensity, pattern, SUVmax) was systematically recorded in > 30 regions of interest (ROIs) linked to SSc in a blind reviewing by 2 independent nuclear medicine physicians using a standardized form. RESULTS: Among the 545 SSc patients followed up in our center, 36, including 22 SSc-ILDs, had a PET/CT, whose indication was cancer screening in most cases. The mean ± SD age was 57.9 ± 13.0 years with 20/36 females. Fourteen patients had a disease duration of less than 2 years. A third had anti-centromere antibodies and 27.8% had anti-topoisomerase antibodies. Pulmonary FDG uptakes were higher in SSc patients than in controls (n = 89), especially in those with ILD compared with those without ILD. Pulmonary FDG uptakes were positively correlated with the ILD severity (fibrosis extent, %FVC, and %DLCO). No significant difference was found in the FDG uptakes from extrathoracic ROIs. Progressing SSc-ILDs within the 2 years after PET/CT (n = 9) had significant higher pulmonary FDG uptakes at baseline than stable SSc-ILDs (n = 13). CONCLUSION: PET/CT could be a useful tool in the assessment of the severity and the prediction of pulmonary function outcome of SSc-ILD.
Assuntos
Doenças Pulmonares Intersticiais , Escleroderma Sistêmico , Adulto , Idoso , Feminino , Fluordesoxiglucose F18 , Humanos , Pulmão/diagnóstico por imagem , Doenças Pulmonares Intersticiais/diagnóstico por imagem , Doenças Pulmonares Intersticiais/etiologia , Pessoa de Meia-Idade , Projetos Piloto , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Tomografia por Emissão de Pósitrons , Estudos Retrospectivos , Escleroderma Sistêmico/complicações , Escleroderma Sistêmico/diagnóstico por imagemRESUMO
BACKGROUND: The aim of this study was to evaluate the role of dual isotope 123Iodine/99mTc-MIBI thyroid scintigraphy (IMS) in discriminating between malignant and benign lesions in indeterminate nodules using quantitative analysis methods. METHODS: Thirty-five consecutive patients with thyroid nodules of indeterminate or non-diagnostic cytology and cold on 123Iodine scintigraphy (10 Bethesda I, 24 Bethesda III-IV, 1 in which cytology was impossible) underwent IMS between 2017 and 2019 with uptake quantification at two time points ahead of thyroidectomy: early and late. Images were analyzed by two blinded physicians. RESULTS: Twelve nodules were malignant and 23 benign on histopathology. Mean uptake values were lower in benign than in malignant nodules at both time points: early, 8.7±4.1 versus 12.9±3.5 (P=0.005); and late, 5.3±2.7 versus 7.7±1.1 (P=0.008). Interobserver reproducibility was excellent. The intraclass correlation coefficient was 0.86 in benign and 0.92 in malignant lesions for early uptake result (ER) and 0.94 and 0.85 respectively for late uptake result (LR). The optimal LR cut-off to exclude a diagnosis of malignancy was set at 5.9 . The sensitivity, specificity, positive predictive value, negative predictive value and accuracy of this cut-off were, respectively, 100%, 65.2%, 60%, 100% and 77.1%. CONCLUSION: Despite some study limitations, quantitative analysis of 99mTc-MIBI thyroid scintigraphy had a good reproducibility, which could help to rule out malignancy in non-diagnostic or indeterminate thyroid nodules and thereby reducing the number of patients undergoing unnecessary surgery when LR is below 5.9.
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Radioisótopos do Iodo , Cintilografia/métodos , Tecnécio Tc 99m Sestamibi , Neoplasias da Glândula Tireoide/diagnóstico por imagem , Nódulo da Glândula Tireoide/diagnóstico por imagem , Adulto , Idoso , Biópsia por Agulha Fina , Diagnóstico Diferencial , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Estudos Retrospectivos , Sensibilidade e Especificidade , Neoplasias da Glândula Tireoide/patologia , Neoplasias da Glândula Tireoide/cirurgia , Nódulo da Glândula Tireoide/patologia , Nódulo da Glândula Tireoide/cirurgia , UltrassonografiaRESUMO
PURPOSE: Radioimmunotherapy (RIT) is a new treatment option for patients with non-Hodgkin lymphoma (NHL). Response to RIT currently remains difficult to predict using conventional prognostic factors and could be refined using functional imaging. The goal of this work is to evaluate the value of (18)F-fluorodeoxyglucose (FDG) positron emission tomography (PET) in predicting response to Yttrium 90-labeled monoclonal antibodies for patients with NHL. METHODS: Thirty-five patients with NHL who had undergone (18)F-FDG PET prior to RIT with either (90)Y-ibritumomab tiuxetan (group A; n = 17) or (90)Y-epratuzumab tetraxetan (group B; n = 18) were included in this retrospective study. Four functional criteria were determined for each tumour lesion in a given patient: maximum and mean standard uptake values (SUVmax and SUVmean), functional lesion volume (LVol) and total lesion glycolysis (TLG, product of the volume and the SUVmean). For each patient, we determined highest SUVmax and SUVmean, cumulative TLG (TLGcum) and sum of all LVol (TVol) and compared their predictive value on response (complete or partial response according to IWC) to RIT with those of conventional prognostic factors in group A and B. RESULTS: A total of 154 lesions were analysed. Nineteen patients (54%) responded to RIT according to IWC. In group A, response rate was 54, 75 and 75% in patients with a SUV max <20 g/ml, a TVol <100 ml and a TLGcum <1060 g, respectively while no patient above these thresholds responded (p < 0.005). In group B, the response rate was 93% for with SUVmax <15 g/ml while no patient above this threshold responded. With TLGcum below 1,360 g, 100% of the patient responded, compared with 37% of patients whose TLGcum was above this threshold (p < 0.05). By contrast, conventional prognostic factors failed to predict response. CONCLUSIONS: Our preliminary results indicate that pre-therapy (18)F-FDG PET functional parameters such as SUVmax and TLG may help predicting more accurately response to single agent Y90 based RIT.
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Fluordesoxiglucose F18 , Linfoma não Hodgkin/diagnóstico por imagem , Linfoma não Hodgkin/radioterapia , Tomografia por Emissão de Pósitrons , Radioimunoterapia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Seguimentos , Lógica Fuzzy , Glicólise , Humanos , Linfoma não Hodgkin/patologia , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Resultado do Tratamento , Carga TumoralRESUMO
We retrospectively investigated the prognostic value of the metabolic bulk volume (MBV), defined as the metabolic volume of the largest lesion, in 106 patients with diffuse large B-cell lymphoma who underwent baseline 18FDG PET-CT. Semi-automatically segmented (41% SUVmax) total metabolic tumor volume (TMTV) and MBV underwent receiver operating characteristic analysis, identifying optimal thresholds of 147 cm3 for the TMTV and 41.5 cm3 for the MBV. A low TMTV and a low MBV were significantly associated with longer progression-free survival (PFS) and overall survival (OS). According to Cox multivariate analysis, the TMTV and MBV were independent predictors, respectively, for PFS (HR = 3.501), and OS (HR = 7.242). The TMTV and MBV classification were discordant in 18.9% of patients with a 5-year PFS rate of 100% for patients with low MBV/high TMTV and 74% for high MBV/low TMTV. The baseline MBV can be an efficient tool for the risk stratification of aggressive lymphoma.
Assuntos
Fluordesoxiglucose F18 , Linfoma Difuso de Grandes Células B , Humanos , Linfoma Difuso de Grandes Células B/diagnóstico por imagem , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Prognóstico , Estudos RetrospectivosRESUMO
PURPOSE OF REVIEW: To review the current status of advanced imaging techniques in identification of organ-confined prostate cancer with a focus on their impact on patient management. RECENT FINDINGS: Transrectal ultrasound suffers from poor accuracy despite significant technical improvements. Generally used to distinguish cancers with extraprostatic spread, MRI is now focusing on intraprostatic prostate cancer identification. At 1.5T, the most recent high-resolution pelvic phased-array coils provide excellent imaging of the whole gland, including this challenging anterior part. Improvements in accuracy for cancer detection and volume estimation result from dynamic contrast-enhanced and diffusion-weighted imaging sequences. Histological correlations showed high sensitivity/specificity for significant volume cancers. 3T MRI scanners will improve these results. Most of the recent PET/computed tomography imaging studies use choline derivatives ((11)C-choline and (18)F-fluorocholine). Their results are promising but insufficient to be currently recommended in routine practice. SUMMARY: Considerable advances have been made in the identification of organ-confined prostate cancer with multiparametric MRI. Only prebiopsy MRI can provide best quality of cancer assessment and allows for targeting biopsies. It is hoped that advances in 3T MRI as well as in radiotracers for PET/computed tomography will further improve diagnosis, treatment selection, planning and outcomes.