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PURPOSE: The purpose was to explore the effects of total-body PET/CT with half-dose 18F-FDG activity on image quality, compared with those of conventional PET/CT with clinical routine full-dose 18F-FDG in lung cancer. METHODS: Fifty-six primary lung cancer patients who underwent total-body PET/CT on a uEXPLORER scanner with half-dose (1.85 MBq/kg) 18F-FDG activity before treatment were retrospectively studied; among them, 28 patients were confirmed by postoperative pathologic examination and 28 patients by biopsy. After matching with the pathological study results, the other 28 patients with lung cancer who underwent surgery were selected for the full-dose (3.70 MBq/kg) group. Patients in the full-dose group were studied with a conventional uM780 PET/CT scanner. The acquisition time of the half-dose group was 15 min, split into 4-min and 2-min duration groups, which were all referred to as G15, G4 and G2, respectively. The PET/CT scanning speed in the full-dose group was 2 min/bed. Image quality was evaluated by subjective and objective analyses. The subjective analysis method was carried out with a 5-point scale (5-excellent, 1-poor). Objective analysis indicators of PET image quality included the SUVmax, SUVmean and signal-to-noise ratio (SNR) of the liver; the SUVmax and SUVmean of the blood pool; and the SUVmax and tumour-to-background ratio (TBR) of the lesions. G15 served as the reference for G2 and G4 to test lesion detectability. RESULTS: Image quality scores in G2 (4.3 ± 0.7) were significantly higher than those in the full-dose group (3.7 ± 0.6) (p = 0.004). The mean and SD of the image quality scores in G4 and G15 were 4.9 ± 0.2 and 5.0 ± 0.0, respectively. The liver SNR in G2 was significantly higher than that in the full-dose group; the corresponding SNR were 11.7 ± 1.5 and 8.3 ± 1.2 (p < 0.001), respectively. The liver SNR significantly increased with the time of acquisition among G2, G4 and G15 (11.1 ± 1.7, 15.2 ± 3.4 and 30.5 ± 6.0, all p < 0.05). G15 served as the reference, and all these lesions (100%) could be identified by G2 and G4. CONCLUSION: Total-body PET/CT with half-dose 18F-FDG activity in G2 and G4 achieved comparable image quality to conventional PET/CT, and its image quality was better than that of conventional PET/CT with clinical routine full-dose 18F-FDG in lung cancer.
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Fluorodesoxiglucosa F18 , Neoplasias Pulmonares , Humanos , Neoplasias Pulmonares/diagnóstico por imagen , Tomografía Computarizada por Tomografía de Emisión de Positrones , Tomografía de Emisión de Positrones , Estudios Retrospectivos , Tomografía Computarizada por Rayos XRESUMEN
OBJECTIVE. The purpose of this article is to describe the clinical applications of a total-body PET scanner and discuss future expectations. CONCLUSION. PET has been widely used in the fields of oncology, neurology, and cardiology. However, current PET scanners have limitations, including long scanning time, low signal-to-noise ratio, and high dose of ionizing radiation. Total-body PET with a long scan range provides solutions to these problems, markedly increasing the sensitivity of the system.
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Tomografía Computarizada por Tomografía de Emisión de Positrones/métodos , Imagen de Cuerpo Entero , Predicción , Humanos , Tomografía Computarizada por Tomografía de Emisión de Positrones/tendencias , Imagen de Cuerpo Entero/tendenciasRESUMEN
BACKGROUND: PET/MR is transferring from a powerful scientific research tool to an imaging modality in clinical routine practice. Whole body PET/MR screening usually takes 30-50 minutes to finish, during which a few factors might induce patient discomfort and further cause degraded image quality. The aim of this report is to investigate the patients' perception of the imaging procedure and its correlation with image quality. METHODS: One hundred and twenty patients (63 males and 57 females, average age = 51.3 years, range 22-70 years) who had been diagnosed with cancer or had previous history of cancer were recruited and scanned with a simultaneous PET/MR system. A questionnaire was given to all patients retrospectively after the PET/MR scan, which has nine questions to assess patients' feeling of the scan on a Likert scale scoring system (1-5, 1 as most satisfied). All PET/MR images were also visually examined by two experts independently to evaluate the quality of the images. Six body locations were assessed and each location was evaluated also with a Likert scale scoring system (1-5, 5 as the best quality). Mann-Whitney U-test was used for statistical analysis to check if there is significant correlation between image quality and patient perceptions. RESULTS: With a total of 120 patients, 118 questionnaires were filled and returned for analysis. The patients' characteristics were summarized in Table 4. The statistics of the patients' perception in the questionnaire were illustrated in Tables 5-7. Statistical significant correlations were found between MR image quality and patients' characteristics/perception. CONCLUSION: Our results show that PET/MR scanning is generally safe and comfortable for most of the patients. Statistical analysis does not support the hypothesis that bad patient's perception leads to degraded image quality.
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Procesamiento de Imagen Asistido por Computador/métodos , Imagen Multimodal/métodos , Neoplasias/diagnóstico , Comodidad del Paciente/estadística & datos numéricos , Garantía de la Calidad de Atención de Salud/normas , Encuestas y Cuestionarios , Imagen de Cuerpo Entero/métodos , Adulto , Anciano , Estudios de Evaluación como Asunto , Femenino , Humanos , Imagen por Resonancia Magnética/métodos , Masculino , Persona de Mediana Edad , Neoplasias/diagnóstico por imagen , Tomografía de Emisión de Positrones/métodos , Estudios Retrospectivos , Tomografía Computarizada por Rayos X/métodos , Flujo de Trabajo , Adulto JovenRESUMEN
OBJECTIVES: To determine the sensitivity of breast-specific gamma imaging (BSGI) in diagnosing breast cancer and assess the potential correlation between the semiquantitative index of BSGI and biologic markers, molecular subtypes, and clinicopathologic characteristics of breast cancer. MATERIALS AND METHODS: The sensitivity of BSGI for breast cancer was retrospectively assessed in 102 female breast cancer patients who underwent BSGI before surgery and was compared with that of ultrasonography and mammography. BSGI was visually graded on the basis of the Society of Nuclear Medicine and Molecular Imaging guideline. Tracer uptake in the cancer as the lesion to nonlesion ratio (L/N) was calculated semiquantitatively and was subsequently correlated to tumor biologic markers, molecular subtypes, and clinicopathologic characteristics. RESULTS: The sensitivity of BSGI for breast cancer by visual analysis was 94.1% (96/102) in our cohort, which was 100% (47/47) in the subgroup of patients with a tumor size more than 2.0 cm and 89.1% (49/55) in the subgroup of patients with a size less than or equal to 2.0 cm. The sensitivity of BSGI was significantly higher than that of ultrasonography of 84.2% (85/101) (P=0.022) and mammography of 84.5% (60/71) (P=0.037). There was no significant correlation between the L/N and expressions of estrogen receptor, progesterone receptor, human epidermal growth factor receptor 2, and antigen Ki-67, and the subtypes or histologic grade of the cancer (P>0.05). However, the value of L/N was associated with infiltration degree (P=0.005), axillary lymph node status (P=0.029), and tumor size (P=0.002). Multivariate analysis further indicated that the value of L/N was correlated with infiltration degree (P=0.016) and tumor size (P=0.002). CONCLUSION: BSGI has a high sensitivity for detecting primary breast cancer. The value of L/N on BSGI was independently related to infiltration degree and tumor size of breast cancer, but not to expression of tumor receptor markers and histologic grade.
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Biomarcadores de Tumor/metabolismo , Neoplasias de la Mama/diagnóstico , Neoplasias de la Mama/metabolismo , Interpretación de Imagen Asistida por Computador/métodos , Cintigrafía/métodos , Tecnecio Tc 99m Sestamibi , Adulto , Anciano , Anciano de 80 o más Años , Neoplasias de la Mama/patología , Femenino , Humanos , Persona de Mediana Edad , Variaciones Dependientes del Observador , Radiofármacos , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Estadística como AsuntoRESUMEN
OBJECTIVES: Breast cancer is the most common malignancy for females worldwide. This study was to evaluate the application of dual-phase breast-specific gamma imaging (BSGI) in detecting primary breast cancer. METHODS: Seventy-six patients with indeterminate breast lesions that underwent dual-phase BSGI enrolled in this study. All included lesions were confirmed by pathology. BSGI was evaluated based on the visual interpretation and dual-phase semi-quantitative indices of lesion to non-lesion ratio (L/N), which were compared with pathological results. The optimal visual analysis and L/N for double-phase were calculated through receiver operating characteristic curve analysis. RESULTS: Among 76 patients, 92 lesions were finally confirmed by the surgery and pathology, with 54 malignant and 38 benign lesions. Both early and delayed L/N of malignant breast diseases were significantly higher than those of benign (3.18±1.57 vs 1.53±0.59, and 2.91±1.91 vs 1.46±0.54, P<0.05). The optimal visual interpretation is over grade 3, and cut-off L/N was 2.06 and 1.77 for early and delayed imaging, respectively. Compared with visual analysis over grade 3 (77.8 and 81.6%), optimal early L/N (81.5 and 92.1%) or delayed L/N (79.5 and 89.5%) alone, the sensitivity and specificity of visual combined with early-phase L/N in diagnosing primary breast cancer are higher, which were 85.2 and 92.2%, respectively. CONCLUSIONS: The combination of visual and semi-quantitative analysis could improve the sensitivity and specificity of BSGI in detecting primary breast cancer. In addition, the potential value of delayed BSGI in diagnosing primary breast cancer should be further investigated in large samples.
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Neoplasias de la Mama/diagnóstico por imagen , Rayos gamma , Tecnecio Tc 99m Sestamibi , Adulto , Anciano , Anciano de 80 o más Años , Reacciones Falso Negativas , Reacciones Falso Positivas , Femenino , Humanos , Interpretación de Imagen Asistida por Computador , Persona de Mediana Edad , Especificidad de Órganos , CintigrafíaRESUMEN
Introduction. Lymphocytic infiltration and specific lymphocytes subsets may play important roles in papillary thyroid carcinoma (PTC) progression and prognosis. In this study, we try to understand the influence of (131)I radioablation on the important lymphocytes subtypes of regulatory T and B cells (Tregs and Bregs). Methods. Peripheral blood mononuclear cells from 30 PTC patients before and after (131)I therapy, and 20 healthy donors were collected. The expression of Tregs (CD4(+)CD25(+)CD127(-/low)) and B cell (CD5(+)CD19(+)) and production and secretion of interleukin 10 (IL-10) were analyzed by FACS and ELISA assay, respectively. Results. For Tregs percentage in peripheral blood lymphocytes, there was no difference between pretreatment and control and between posttreatment and control. Compared with pretherapy, increased Tregs infiltration was noted in posttherapy (P < 0.05). Although no difference was between pretreatment and control, compared with these two groups, decreased CD19(+) and CD5(+)CD19(+) B cell percentage in posttreatment was observed (P < 0.05). Among these groups, no significant difference was displayed in intracellular IL-10 production and extracellular IL-10 secretion. Conclusions. (131)I Radioablation increased Tregs and decreased CD19(+) and CD5(+)CD19(+) B cells percentage after treatment. However, it has no effect on IL-10 and lymphocytes in peripheral blood. Therefore, longer follow-up of Tregs and Bregs should be further investigated.