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1.
Radiography (Lond) ; 30(3): 971-977, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38663216

RESUMO

INTRODUCTION: Positron emission tomography/computed tomography (PET/CT) has an established role in evaluating patients with lung cancer. The aim of this work was to assess the predictive capability of [18F]Fluorodeoxyglucose ([18F]FDG) PET/CT parameters on overall survival (OS) in lung cancer patients using an artificial neural network (ANN) in parallel with conventional statistical analysis. METHODS: Retrospective analysis was performed on a group of 165 lung cancer patients (98M, 67F). PET features associated with the primary tumor: maximum and mean standardized uptake value (SUVmax, SUVmean), total lesion glycolysis (TLG) metabolic tumor volume (MTV) and area under the curve-cumulative SUV histogram (AUC-CSH) and metastatic lesions (SUVmaxtotal, SUVmeantotal, TLGtotal, and MTVtotal) were evaluated. In parallel with conventional statistical analysis (Chi-Square analysis for nominal data, Student's t test for continuous data), the data was evaluated using an ANN. There were 97 input variables in 165 patients using a binary classification of either below, or greater than/equal to median survival post primary diagnosis. Additionally, phantom study was performed to assess the most optimal contouring method. RESULTS: Males had statistically higher SUVmax (mean: 10.7 vs 8.9; p = 0.020), MTV (mean: 66.5 cm3 vs. 21.5 cm3; p = 0.001), TLG (mean 404.7 vs. 115.0; p = 0.003), TLGtotal (mean: 946.7 vs. 433.3; p = 0.014) and MTVtotal (mean: 242.0 cm3 vs. 103.7 cm3; p = 0.027) than females. The ANN after training and validation was optimised with a final architecture of 4 scaling layer inputs (TLGtotal, SUVmaxtotal, SUVmeantotal and disease stage) and receiving operator characteristic (ROC) analysis demonstrated an AUC of 0.764 (sensitivity of 92.3%, specificity of 57.1%). CONCLUSION: Conventional statistical analysis and the ANN provided concordant findings in relation to variables that predict decreased survival. The ANN provided a weighted algorithm of the 4 key features to predict decreased survival. IMPLICATION FOR PRACTICE: Identification of parameters which can predict survival in lung cancer patients might be helpful in choosing the group of patients who require closer look during the follow-up.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Fluordesoxiglucose F18 , Neoplasias Pulmonares , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Compostos Radiofarmacêuticos , Humanos , Masculino , Carcinoma Pulmonar de Células não Pequenas/diagnóstico por imagem , Carcinoma Pulmonar de Células não Pequenas/mortalidade , Carcinoma Pulmonar de Células não Pequenas/patologia , Neoplasias Pulmonares/diagnóstico por imagem , Neoplasias Pulmonares/mortalidade , Neoplasias Pulmonares/patologia , Estudos Retrospectivos , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos , Feminino , Idoso , Pessoa de Meia-Idade , Adulto , Idoso de 80 Anos ou mais , Valor Preditivo dos Testes , Redes Neurais de Computação
3.
Nuklearmedizin ; 43(5): 150-7, 2004 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-15480503

RESUMO

AIM: It has been shown that exercise may lead to the myocardial stunning with reduction of LVEF, persisting for some time despite recovery of perfusion. The aim of this study was to check whether the post-stress decrease of LVEF lasts as long as 3 h after exercise. PATIENTS, METHODS: The study was performed in 46 patients with CAD and in 10 normals (NMS). All patients underwent myocardial gSPECT after (99m)Tc-tetrofosmin injection at rest and during stress with 2-day protocol. SPECT was started 1h after tracer injection at rest (R) and twice: 1h (S1) and 3hs (S3) after injection at stress. LVEF was calculated by the method of Germano et al. RESULTS: All LVEF values were significantly lower in CAD patients than in the control group. In NMS mean LVEF was at rest similar to those obtained 1 h and 3 h after stress injection (59.0 +/- 4.1, 60.0 +/- 5.9, 58.0 +/- 4.6, respectively; p >0.05). A post-exercise decrease of LVEF was observed in 2 normal patients both at S1 and at S3. In CAD group LVEF values were lower at S1 than at R (50.8 +/- 13.6 versus 49.3 +/- 12.8; p <0.05) and at S3 were lower than at S1 (49.3 +/- 12.8 versus 46.0 +/- 12.2;p <0.001). A significant decrease of LVEF was found in 18/46 patients 1 h post stress and in 36/46 3 h post stress. In patients with reversible perfusion decrease, a significant correlation was found between post-exercise deterioration of perfusion and post-exercise LVEF reduction both at S1 (r = 0.744; p <0.02) and at S3 (r = 0.734; p <0.02). Stress induced decrease in LVEF correlated also with severity of perfusion abnormalities. CONCLUSIONS: In the majority of patients with CAD physical stress applied for diagnostic purposes results in an impairment of the LV function. A decrease of the LVEF is observed 1 h after exercise, but it increases in frequency and grows stronger during the next 2 h. The post-stress LVEF reduction is related to the severity of perfusion abnormalities. Patients with CAD who underwent diagnostic stress test should remain under observation during several hours after termination of exercise.


Assuntos
Doença das Coronárias/diagnóstico por imagem , Teste de Esforço , Coração/diagnóstico por imagem , Compostos Organofosforados , Compostos de Organotecnécio , Radioisótopos , Função Ventricular Esquerda/fisiologia , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Compostos Organofosforados/farmacocinética , Compostos de Organotecnécio/farmacocinética , Radioisótopos/farmacocinética , Fatores de Tempo , Tomografia Computadorizada de Emissão de Fóton Único , Disfunção Ventricular Esquerda/diagnóstico por imagem
5.
Eur J Nucl Med ; 27(9): 1318-25, 2000 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11007513

RESUMO

[111In-diethylene triamine penta-acetic acid-D-Phe1]-octreotide (DTPA-octreotide) scintigraphy has gained widespread acceptance as a diagnostic clinical procedure in oncology for imaging somatostatin receptor-positive tumours. However, indium-111 as a radiolabel has several drawbacks, including limited availability, suboptimal gamma energy and high radiation burden to the patient. We have recently reported on the preclinical development of 99mTc-EDDA/HYNIC-TOC, a new octreotide derivative which showed promising results both in vitro and in vivo. We now report our initial clinical experiences with this new radiopharmaceutical in ten oncological patients. The clinical diagnoses were: carcinoid syndrome (n=5), thyroid cancer (n=3), pancreatic cancer (n=1) and pituitary tumour (n=1). The biodistribution and kinetics of 99mTc-EDDA/HYNIC-TOC were compared with those of 111In-DTPA-octreotide in six cases, and with those of 111In-DOTA-TOC in five cases. With the new tracer tumours were imaged within 15 min after injection and showed the highest target/non-target ratios 4 h after injection. Tumour uptake persisted up to 20 h p.i. The rate of blood clearance was similar to that of 111In-DTPA-octreotide but faster than that of 111In-DOTA-TOC, while urinary excretion was lower compared with the 111In derivatives. Semi-quantitative region of interest analysis showed that 99mTc-EDDA/HYNIC-TOC produced higher tumour/organ (target/non-target) ratios than the 111In derivatives, especially in relation to heart and muscle. Significantly more lesions could be detected in 99mTc images. We conclude that 99mTcEDDA/HYNIC-TOC shows better imaging properties for the identification of somatostatin receptor-positive tumour sites than currently available 111In-labelled octreotide derivatives.


Assuntos
Ácido Edético/análogos & derivados , Radioisótopos de Índio , Neoplasias/diagnóstico por imagem , Octreotida/farmacocinética , Compostos Radiofarmacêuticos , Receptores de Somatostatina/análise , Tecnécio , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Cintilografia
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