AIM Evaluate the therapy impact of initial staging in patients diagnosed with prostate cancer by 18 F-choline PET/MRI hybrid technique. MATERIAL A prospective study which included 31 patients diagnosed with prostate cancer; Gleason > 7; mean PSA 13.6 ng/mL (range 6.3-20.6). PET/MRI studies were acquired simultaneously with hybrid equipment (SIGNA.3T, GE) following intravenous injection of 185 ± 18.5MBq of 18F-choline: - Early/prostate imaging: PET emission + multiparametric MR: DIXON-T1-T2-diffusion-gadolinium. - Late/whole-body imaging: PET emission + MR: DIXON-T1-T2-diffusion-STIR sequences. Images were visually evaluated. SUV & ADC & textures were also calculated. Treatment selection was based upon Oncology Committee consensus decision. RESULTS Procedure was well tolerated in all patients, and no artifacts were reported. MRI was superior in T staging in eight patients (25.8%) (Likert: 2-3), whereas PET increased MRI sensitivity in three patients (9.7%) (PIRADS: 3). PROSTATE LESION LOCATION Peripheral 91.4%, transitional 8.6%. SUVmax threshold: 2.95: sensitivity 92.9%, specificity 66.7%. No correlation SUV vs. ADC. Better distinction between stage T2 vs. T3 using the DiscrLin model with NG = 16 (AUC 0.7767 ± 0.3386). PET was superior to T2 in textures analysis (0.588 vs. 0.412). Seventeen patients (54.8%) were staged ≥ T3, with surgical treatment being contraindicated. Fifteen patients (48.4%) presented with extra-prostatic disease: 8/31 oligometastatic and 7/31 multiple metastasis. Therapy approach following PET/MRI was: radical treatment in 24/31 patients (77.4%), 14 radical prostatectomy and 10 MRI-guided radiotherapy; systemic treatment in 7/31 patients (22.6%). CONCLUSION 18F-choline PET/MRI had a complementary role for the T staging, with a high detection rate for NM infiltration. PET/MRI findings allowed patients to be directed either to prostatectomy or MRI-guided radiotherapy, and thus avoiding radicaltreatment in 22.6% of patients.
The incidence of melanoma in children is uncommon, being particularly rare in children under 10 years-old. However, this disease is increasing by a mean of 2% per year. As in adults, the lymph node status is the most important prognostic factor, crucial to performing the selective sentinel lymph node biopsy (SLNB). We report 3 cases of paediatric patients of 3, 4 and 8 years-old, in which SLNB was performed for malignant melanoma. Paediatric age implies greater technical difficulty to the scintigraphy scan due to poor patient cooperation, with mild sedation required in some cases, and only being able to acquire planar images in other cases. SPECT/CT was only performed in the oldest patient. In our cases, SLNB was useful for selecting the least invasive surgery in order to reduce morbidity.
The new diagnostic criteria for Alzheimer's disease (AD) acknowledges the interest given to biomarkers to improve the specificity in subjects with dementia and to facilitate an early diagnosis of the pathophysiological process of AD in the prodromal or pre-dementia stage. The current availability of PET imaging biomarkers of synaptic dysfunction (PET-FDG) and beta amyloid deposition using amyloid-PET provides clinicians with the opportunity to apply the new criteria and improve diagnostic accuracy in their clinical practice. Therefore, it seems essential for the scientific societies involved to use the new clinical diagnostic support tools to establish clear, evidence-based and agreed set of recommendations for their appropriate use. The present work includes a systematic review of the literature on the utility of FDG-PET and amyloid-PET for the diagnosis of AD and related neurodegenerative diseases that occur with dementia. Thus, we propose a series of recommendations agreed on by the Spanish Society of Nuclear Medicine and Spanish Society of Neurology as a consensus statement on the appropriate use of PET imaging biomarkers.
Organochlorine pesticides (OCPs) and polycyclic aromiatic hydrocarbons (PAHs) were analyzed in surface sediment samples collected from Qinghai Lake, the largest lake in China, which is situated in the northeast Qinghai–Tibet plateau at an altitude of 3200 m. The concentrations of these pollutants ranged from 0.02 to 1.00 ng/g for hexachlorocyclohexanes (HCHs), from not detected to 0.86 ng/g for dichlorodiphenyltrichloroethanes (DDTs), from 0.26 to 1.73 ng/g for OCPs, and from 366 to 966 ng/g for PAHs. The predominance of α-HCH suggests that long-range atmospheric transport is an important source for HCHs. A low α- to γ-HCH ratio (3.87 on average) indicates the possible usage of lindane in the drainage basin. The high percentage of p,p′-DDE and p,p′-DDD and the low percentage of o,p′-DDT indicated significant degradation from previous inputs, and no recent inputs of dicofol derived DDT. Based on the analysis of the component ratios, PAHs were found to be primarily from the combustion of biomass and coal-based fossil fuels. Using the Canadian sediment guidelines, PAHs are of greater ecological concern than OCPs in Qinghai Lake.
Iodine kinetic studies were performed in seven patients with hot thyroid nodules, three diffuse toxic goiters and one normal control, using a double label technique (131I and 125I-thyroxine). The investigation was complemented by partial kinetic studies in 29 further subjects, including normal control subjects and euthyroid or hyperthyroid patients with diffuse or nodular goiter. Thyroid iodide uptake and hormonal secretion parameters were significantly increased, up to twice control values, in hot nodules without clinical signs of thyrotoxicosis. Values similar to those of Graves' disease were found in toxic nodular goiter. The exchangeable iodine pool was markedly reduced in those glands where the nodule was adenomatous and radioiodide uptake of normal parenchyma was completely suppressed. In two cases of nontoxic hot nodule with histologic diagnosis of multinodular goiter, and incomplete suppression of the “extranodular” thyroid, the exchangeable iodine pool was comparable to that of normals. The T4 disposal rate was increased, mainly due to a significantly higher metabolic deiodination which seemed to keep pace with the increased T4 production rate in nontoxic nodules. This could be the reason why the mean peripheral T4 pool of clinically nontoxic patients with hot nodules is comparable to that of normal persons, and there are no evident signs of hypermetabolism in spite of the greater thyroid hormone production. A significant “non-T4-iodine” release, probably mainly iodide, was found in every subject. The amount of iodine lost by the thyroid through this “iodide leak” did not relate to the T4 secretion rate but seems to be directly related to the thyroid exchangeable iodine pool size.
The aim of present investigation was to evaluate biodistribution in healthy animals and in tumor models of the radiopharmaceuticals Tc-99m-EDDA/tricine-HYNIC-Lys3-Bombesin (HYNIC-Lys3-BN) and Tc-99m-NA/tricine-HYNIC-Lys3-BN. Biodistribution and pharmacokinetics were carried out over 24 hours. To do so, 24 healthy Wistar rats were used and were administered 37.0 +/- 0.8 MBq/rat of each radiopharmaceutical. For the tumor model study, 20 CD-1 nude mice were used and prostate tumors (PC3) were implanted in all the mice. Ten days later, tumor volumes were calculated and 40.00 +/- 0.04 MBq/mice of each radiopharmaceutical were injected. Both showed high radiochemical purity: 98.08 +/- 0.25% for EDDA/tricine product and 95.1 +/- 0.3% for the conjugate with NA/tricine. Uptake of the radiopharmaceutical with NA/tricine was significantly higher in organs of the reticulo-endothelial system of healthy Wistar rats during 24 h, specifically in the liver and spleen. Both labeled compounds showed no significant differences between their blood elimination half lives. Average of tumor growth was 0.93 +/- 0.02 cm3 and affinity for tumors showed a growing and specific binding of both radiopharmaceuticals, although it was significantly higher for the EDDA/tricine conjugate. This outcome made it possible to corroborate the direct relationship between the density of gastrin releasing peptide and its receptors (GRPr) and the variation of the accumulation of the radiopharmaceuticals in the tumor. Use of EDDA/tricine as coligand is more appropriate than NA/tricine for labeling of HYNIC-Lys3-BN with Tc-99m. (C) 2011 Elsevier Espana, S.L. and SEMNIM. All rights reserved.
A 58 year old female was referred for FDG-PET/CT for restaging of endometrial adenocarcinoma. For evaluation of treatment, no metastases were detected on FDG-PET/CT which was performed 18 months later after the surgery. During follow-up, FDG-PET/CT was performed 6 months later than the previous FDG-PET/CT for restaging. A lesion with increased metabolic activity (SUV max: 10.21) was detected at spleen which was not seen on previous FDG-PET/CT scan. The lesion was consistent with metastasis of endometrial carcinoma.
Spondylodiscitis affects a small proportion of all patients with locomotor system infections, however its early diagnosis is important due to its potential morbidity. Magnetic resonance imaging is the diagnostic method of choice. Nonetheless, it has certain limitations and is not suitable for all patients. The conventional scintigraphic studies for evaluating spondylodiscitis are those performed with (99m)Tc-HDP and (67)Ga-citrate. However, their poor image resolution is a disadvantage of these techniques. The use of hybrid Single Photon Emission Computed Tomography-Computed Tomography (SPECT-CT) improves detection of the disease by combining functional and anatomical images. We present 9 patients with suspicion of spondylodiscitis who underwent sequential bone scintigraphy with (99m)Tc-HDP and SPECT-CT with (67)Ga-citrate, with positive findings confirmed by clinical monitoring for at least 6 months.
The aim of this study was to assess the role of labelled leukocyte scintigraphy in the diagnosis and monitorization of response to therapy of patients with active bronchiectasis. Twenty patients underwent 99mTechnetium hexamethylpropyleneamine oxime (99mTc-HMPAO) labelled white blood cell (WBC) scintigraphy. A second scintigraphy was performed in 13 patients at 10 day of the treatment. Regional 99mTc-HMPAO WBC uptake and radiologic imaging findings (high resolution computed tomography or Chest X-Ray) in the lungs were classified into 3 categories in 6 lung areas. scintigraphic, radiological and clinical disease scores were calculated for all patients. An abnormal accumulation was visually observed in 19 of 20 patients on the pre-treatment scans, the scintigraphy showing 95% sensitivity. A significant difference was found between early and late ratios (P = 0.001) in the pre-treatment scans. The infected areas revealed a significant decrease in uptake ratios on the post-treatment scans compared to the pre-treatment scans (P = 0.001). However, no significant correlation was determined between clinical and radiological scores, clinical and scintigraphic scores and also between scintigraphic and radiological scores (P ≥ 0.05). 99mTc-HMPAO WBC scintigraphy may be a useful tool to evaluate response to therapy in patients with active bronchiectasis. El objetivo de este estudio fue evaluar el papel de la gammagrafía con leucocitos marcados en el diagnóstico y monitorización de la respuesta al tratamiento en pacientes con bronquiectasias activas. Se realizó una gammagrafía con leucocitos marcados con 99mTc-Tecnecio hexametilpropilenoamina oxima (99mTc-HMPAO). Una segunda gammagrafía de control se efectuó en 13 pacientes a los 10 días del tratamiento. La captación regional de los leucocitos 99mTc-HMPAO y los hallazgos de la imagen radiológica (tomografía computarizada de alta resolución o la radiografía de tórax) en 6 zonas pulmonares se clasificaron en 3 categorías. Se calcularon índices gammagráficos, radiológicos y clínicos de actividad o captación en todos los pacientes. Se observó visualmente una acumulación leucocitaria patológica en 19 de 20 pacientes en el estudio pretratamiento, con una sensibilidad del 95% de la gammagrafía. Se encontró una diferencia significativa entre los índices precoces y tardíos (p = 0,001) en la exploración pretratamiento. Las áreas infectadas mostraron una significativa disminución de ratios de captación en la gammagrafía postratamiento respecto a la exploración preterapia (p = 0,001). Sin embargo, no se encontró una correlación significativa entre las puntuaciones de valoración clínica y radiológica, clínica y gammagráfica, y tampoco entre las puntuaciones de la gammagrafía y los radiológicos (p ≥ 0,05). La gammagrafía con 99mTc-HMPAO leucocitos puede ser una herramienta útil para evaluar la respuesta al tratamiento en pacientes con bronquiectasias activas.
Objectives: This retrospective study was designed to investigate the role of fluorodeoxyglucose positron emission tomography/computed tomography (FDG-PET/CT) in determination of recurrence and/or intraabdominal metastasis in patients with ovarian cancer having increased tumor markers or suspicious lesion detected by a contrast-enhanced abdominal CT (ceCT).Materials and methods: A total of 34 female patients who were treated for histopathologically proven ovarian cancer, underwent PET/CT examination for restaging and suspected recurrence. Patients with pathology report, tumor marker levels, ceCT and PET/CT performed within one month were included in the study.Results: A total of 34 patients were included in the study. 25 of 34 patients had high tumor marker (CA 125) level. The remaining 9 patients had suspected recurrence on ceCT imaging with normal tumor marker levels. Recurrence was confirmed by re-operation and biopsy (n = 4), clinical and imaging follow-up (n = 21) in 25 patients with elevated tumor markers. Recurrent disease was not shown in 5 of 25 patients on ceCT imaging and 1 of 25 patients on PET/CT imaging with high CA125 values. Both ceCT and PET/CT revealed recurrent disease in 19 of 25 patients. PET/CT showed more lesions in 11 of 19 patients. Sensitivity, specificity and accuracy of the PET/CT were 96.1%, 100% and 97%, respectively.Conclusion: PET/CT is found as a beneficial method for detection of the recurrence, in patients with increased serum CA 125 level and negative CT findings or with normal CA 125 level and recurrence detected by CT which was performed due to clinical symptoms. (C) 2011 Elsevier Espana, S.L. and SEMNIM. All rights reserved.
