Search

Objective: Oncocytic variant (OV) is an unusual subtype of papillary thyroid cancer whose histopathologic diagnostic criteria, clinicopathologic features and biological behavior are different and have not been comprehensively studied, characterized in literature. Previous studies present conflicting results upon its prognosis. We investigated demographic and clinicopathologic risk factors affecting its prognosis while presenting our clinical experience., Subjects and Methods: This is a retrospective cohort study reviewing 101 patients of OV from an archive of 4500 well-differentiated thyroid cancer patients treated with iodine-131 ( 131 I) between 1991 and 2017. Predefined parameters of age, gender, tumor size (TS), total 131 I dose, time to recurrent disease, overall survival, extrathyroidal extension, multifocality, vascular invasion, accompanying other variants, capsular status of thyroid gland, initial cervical lymph node (LN) metastases, preablation stimulated thyroglobulin level, background thyroiditis and stage were evaluated by statistical comparison between metastatic and nonmetastatic groups., Results: Seventeen cases (17%) developed metastases/recurrence, 70% of the recurrences occured before 24 months. Four patients (4%) died during the follow-up. Metastatic sites were usually cervical LN, local recurrence in thyroid bed and lungs. Multivariate analysis revealed stage (IV) and TS were the main parameters impacting recurrence/metastases. In the follow-up, isolated cervical LN metastases were found in 41% of metastatic cases, while 12% had sole recurrence in thyroid bed. Eighty eight percent of the metastatic disease included locoregional (cervical) and/or remote LN. The recurrences were associated with initial thyroid masses greater than 3.5cm in diameter., Conclusion: We found that the prognosis of OV is not poor in our series. Stage (IV) and tumor size are the main risk factors in metastatic development.

Objective: Multiple nuclear medicine techniques for measuring renal glomerular filtration rate (GFR) are available but some of them are not practical in daily routine use and others have some accuracy issues. Hence the aim of the study was to design a new camera-based approach to measure the GFR and to compare our results with other measured GFR (mGFR) and estimated GFRs (eGFRs) derived from available measurements and equations used in daily clinical practice., Material and Methods: 34 patients were included in the study. ∼74MBq (2mCi) Technetium 99m diethylene-triamine-pentaacetic acid ( 99m Tc-DTPA) was administered to the patients during 5min. A simple formula based on a dilution principle was used to measure GFR (ScinGFR)., Results: Our formula provided similar mGFR results in narrower range as creatinine clearance did and our results correlated well with results derived from other equations. When ScinGFR values were compared to others, there was a significant difference among them (p=0.031) due to difference between the ScinGFR and Cockroft-Gault. When the results of the ScinGFR compared to others without Cockroft-Gault, the difference among them was not significant (p=0.164)., Conclusion: A simple formula considering the extracellular fluid volume was used to predict the split and global kidney functions and despite some discrepancies, good correlation among our results and those derived from available formulas was detected., (Copyright © 2017 Elsevier España, S.L.U. y SEMNIM. All rights reserved.)

Objective: In nearly 20%-30% of patients with differentiated thyroid carcinoma (DTC) relapse and 7% of them die during the next 10 years after initial diagnosis. In 10%-30% of patients with DTC after ablation therapy during the follow-up show a negative iodine-131 ( 131 I) whole-body screening test ( 131 I WBS) and increased serum thyroglobulin (Tg) level. Loss of ability of DTC metastatic lesions to trap 131 I is associated with pure survival and often aggressive disease. Several studies have shown that in DTC cases non trapping 131 I, fluorine-18-fluorodeoxyglucose positron emission tomography ( 18 F-FDG PET) can detect recurrence or metastases with high sensitivity (80%-90%). The purpose of this study was to investigate the clinicopathologic features and other related risk factors of patients with DTC having elevated Tg levels and negative 131 I WBS in which recurrence was detected by 18 F-FDG PET/CT. We tried to study and stratify patients in this grey zone who could benefit from 18 F-FDG PET/CT for the detection of metastases/recurrence according to predefined risk factors not investigated by other researchers., Subjects and Methods: We studied retrospectively 165 DTC patients with elevated Tg levels and a negative 131 I WBS during their follow-up between 2004-2015. Metastases/recurrence was found in 49% of the patients on restaging with 18 F-FDG PET/CT and were compared with nonmetastatic group according to predefined risk factors. These factors were also evaluated in true positive and false negative cases., Results: The sensitivity and specificity of 18 F-FDG PET/CT for detecting recurrent/metastatic disease were 90% and 98.5%, respectively. No apparent predefined risk factor impacting a false negative 18 F-FDG PET/CT was found. Findings in follicular carcinoma, Hürtle cell carcinoma and papillary carcinoma were not different from positive PET findings. The variants of papillary carcinoma also had no statistically difference with regard to 18 F-FDG results., Conclusion: The most important factors affecting a true positive 18 F-FDG PET/CT study were: ETE, high total 131 I dose and the SUVmax values over 4.5.

Unlabelled: Progressive speech and language disorders are commonly referred to as primary progressive aphasia (PPA), which is a clinical syndrome eroding both speech and language. Functional imaging may reveal the cause of this disorder even if structural imaging is absent. Fluorine-18- fluorodeoxyglucose positron emission tomography/computed tomography ((18)F-FDG PET/CT) allows the assessment of neuronal activity by semi-quantitatively measuring glucose metabolism in the brain. In medical literature, (18)F-FDG PET/CT studies show hypometabolic areas in different regions of the brain which are special clues for differentiating the subgroups of PPA., Conclusion: This case was reported to demonstrate the characteristic (18)F-FDG PET CT findings for a semantic variant of PPA.

Objective: Since the effect of time on phase indices is still unclear, the aim of the study was to evaluate the variability of phase indices of the left ventricle which were derived from stress and rest single-photon emission computed tomography (SPECT) imaging acquired at early and late times., Methods: One hundred twenty-one patients (72 men, 49 women) were included into the study. All stress and rest gated myocardial perfusion imaging (gMPI) acquisitions were acquired at two different time points as early in 15 ± 5 min and late in 45 ± 5 min. The peak of the phase histogram (PP), the standard deviation of the phase distribution (SDPH), the width of the band (BPH), and the symmetry (histogram skewness, HS) and peakedness of the phase histogram (histogram kurtosis, HK) which are the parameters for assessing left ventricular systolic dyssynchrony were calculated in all stress and rest SPECT images acquired twice., Results: The phase indices derived from the late rest scans were smaller than those of the early rest scans but, the differences were not significant. When considering the comparisons of phase indices derived from two different time points after stress, PP showed a tendency to decrease (from 160.8 ± 18.3 to 152.5 ± 17.3; p < 0.001) over time but SDPH (from 20.2 ± 10.6 to 22.4 ± 12.2; p = 0.018) and BPH (from 61.5 ± 36.0 to 66.3 ± 37.3; p = 0.045) tended to increase over time. When the post-stress and the resting dyssynchrony parameters derived at two different time points were compared to each other; PP decreased at early and late times approximately 12 and 9 %, respectively, SDPH increased at early and late times approximately 28.5 and 14 %, respectively, and BPH increased at early and late times approximately 23 and 12 %, respectively., Conclusions: In resting conditions, phase indices of the left ventricle, and therefore, the phase histogram tend to remain constant over time but, in conditions after exercise, the phase histogram tend to be long and narrow due to changes in phase indices and it shows tendency to return to resting conditions in time. Therefore, it appears that postexercise acquisition times should be standardized if we want to compare the phase indices results of the studies in the literature.

Objective: Positron emission tomography-computed tomography (PET-CT) imaging of patients with diabetes can be problematic because elevated glucose levels may cause competitive inhibition of [F-18]-2-deoxy-2-fluoro-D-glucose (FDG) uptake in different tissues. Therefore, the aim of the study was to evaluate the biodistribution of FDG in patients with type-2 diabetes mellitus., Methods: Two hundred forty patients were retrospectively enrolled to the study. Study population was divided into three subgroups, named as the normal (group 1), the insulin (group 2) and the oral anti-diabetic (group 3). Unenhanced low-dose CT and PET emission data were acquired from the mid-thigh to the vertex of the skull. FDG uptakes in different organs were evaluated qualitatively or semi-quantitatively., Results: In the diabetic groups, diffuse FDG uptake of the colon was increased (p > 0.001) but segmental FDG uptake was decreased (p > 0.001). Intestinal FDG uptake was detected in 20 % of the study population and only 3 % of these uptakes were in diffuse pattern. Segmental FDG uptake in the bowel was increased significantly in the groups of patients with diabetes (p = 0.002). Maximum standardized uptake values of the liver in the groups 1, 2, and 3 were 2.66 ± 0.6, 3.25 ± 0.9 and 3.16 ± 0.8, respectively, and the difference between the groups was not statistically significant (p = 0.083). Cardiac FDG uptake was decreased significantly in the groups of patients with diabetes (p < 0.001)., Conclusions: According to our results, whole body biodistribution of FDG uptake seems to be changed in patients with type-2 diabetes who were using insulin or oral antidiabetic drugs. Although the use of oral antidiabetic drugs was known to change the biodistribution of FDG, insulin use also seems to change FDG uptake in different organs of diabetic patients.

Objective: A count-based new technique from gated myocardial perfusion single-photon emission tomography (gMPS) was developed to allow the phase analysis providing information about the left ventricular (LV) regional discordance in contractility which is a measure of LV dyssynchrony. Since the phase analysis provides data for evaluating the dyssynchronous LV contraction, it has an important role in diagnosis and management of patients with left ventricular dysfunction. The aim of the study was to assess the presence of left ventricular dyssynchrony in patients with reversible perfusion defects on gMPS scans and normal or near normal coronary arteries at angiography., Methods: 32 patients (19 men, 59 %) with reversible mild perfusion defects on gMPS and normal coronary angiogram were retrospectively enrolled in the study. The peak of the phase histogram, the standard deviation of the phase distribution (PSD), the width of the band (PHB), and the symmetry and peakedness of the phase histogram, which are the assessment parameters for the LV dyssynchrony, were calculated from gMPS scans of patients by means of the phase analysis., Results: Although, five quantitative variables are derived from the phase analysis of gMPS, PSD and PHB are two quantitative indices to assess LV global mechanical dyssynchrony and measurements of PSD (men 24.96 ± 7.31, women 24.26 ± 10.07) and PHB (men 70.1 ± 13.99, women 71.0 ± 30.4) were significantly higher than the those reported in the literature (p < 0.001). No significant differences in gMPS phase analysis indices were found between both sexes except kurtosis., Conclusion: As a conclusion, this study provides the phase analysis to detect LV mechanical dyssynchrony as new evidence supporting the concept that an abnormal scintigraphy finding, rather than being false-positive, may be an early marker of vasomotion changes associated with occult atherosclerosis in patients with normal coronary angiography findings.

The purpose of this study was to determine the clinical significance of (18)F-FDG PET/CT on initial staging and therapy planning in patients with invasive breast cancer. One hundred and forty-one consecutive, biopsy proven preoperative and 195 postoperative high-risk breast cancer patients who were referred for PET/CT for initial staging were included in this retrospective study. The clinical stage had been determined by conventional imaging modalities prior to the PET/CT scan. Of the 141 examined preoperative patients, 19 had clinical stage I (T1N0), 51 had stage IIA (12 T2N0 and 39 T1N1), 49 had stage IIB (2 T3N0 and 47 T2N1), 12 had stage IIIA (11 T3N1, 1 T2N2), 2 had stage IIIB (2 T4N1) and 8 had stage IV. PET/CT modified the staging for 26% of stage I patients, 29% of stage IIA patients, 46% of stage IIB patients, 58% of stage IIIA patients and 100% of stage IIIB patients. PET/CT scans detected extra-axillary regional lymph nodes in 14 (9.9%) patients and distant metastasis in 41 (29%) patients. PET/CT scans detected multifocal lesions in 30 (21%) patients, multicentric lesions in 21 (14%) patients and malign foci in the contralateral breast (bilateral breast cancer) confirmed by biopsy in 5 (3.5%) patients. Of the examined 195 postoperative patients PET/CT detected axillary lymph nodes in 22 (11%) patients, extra-axillary regional lymph nodes in 21 (10%) patients and distant metastasis in 24 (12%) patients. PET/CT findings altered plans for radiotherapy in 22 (11%) patients and chemotherapy was adapted to the meta-static diseases in 24 (12%) patients. PET/CT was revealed to be superior to conventional imaging modalities for the detection of extra-axillary regional metastatic lymph nodes and distant metastases. These features make PET/CT an essential imaging modality for the primary staging of invasive breast cancer, particularly in patients with clinical stages II and III.

Purpose: Cerebral palsy is one of the most common reasons of osteopenia in childhood. Patients have a significantly decreased bone mineral density, and painful fractures with minor traumas are common. Biphosphonates in the treatment of childhood osteoporosis are increasingly being used. This study aimed to evaluate the efficacy of oral alendronate treatment in children with cerebral palsy., Methods: Twenty-six children (16 boys and 10 girls) aged 3 to 17 years who had quadriplegic cerebral palsy and osteopenia were included in the study. The patients received alendronate (1 mg/kg/week), calcium (600 mg/day), and vitamin D(3) (400 U/day) over a year. A complete blood count, kidney and liver functional tests, plasma calcium, phosphate and alkaline phosphatase levels, and lumbar vertebral bone mineral density were measured before and after treatment., Results: Compared with pretreatment values, bone mineral density, serum calcium, and phosphate levels of the patients statistically increased and alkaline phosphatase levels decreased after treatment. No patient needed to interrupt treatment because of side effects., Conclusions: Oral alendronate at a dose of 1 mg/kg/week for the treatment of osteopenia in children with cerebral palsy was found to be safe and effective.

Since, the effect of a large cranial defect on the cerebrospinal fluid (CSF) flow rate is still not clear, this study was designed to evaluate the effect of craniectomy in rabbits by using a radionuclide technique, under in vivo physiologic conditions. Eleven male New Zealand white rabbits were examined. After the injection of technetium-99m-diethylene-triaminepenta-acetic acid into the fourth ventricle of each rabbit, dynamic acquisition for 60 min (1 min per frame) was performed pre-op followed by about one third craniectomy to each animal. Injection of the radiopharmaceutical and the imaging steps were repeated at 24 h (post-op 24 h) and at 7 days (post-op 7 d) after craniectomy. The region of interest (ROI) was drawn around the injection site and a time activity curve was generated. Slopes of each curve were calculated to detect the flow rate of the radiopharmaceutical from the injection site during 60 min. Besides, the count decreased ratio (ROIcounts of the last frame ROI counts of the first frame X100) was calculated. Our results showed that the pre-op values of the slope of the time-activity curve and the count decreased ratio were decreased 24 h and 7 d post-op but statistically significant was only the difference between the above values pre-op and 7 d post-op (P=0.04, P=0.01 respectively). In conclusion, the data of the present study indicate that the CSF flow rate in rabbits decreased 7 d after one third craniectomy.

A 69 years old woman with chronic low back pain referred to our Department for bone scintigraphy. Patient did not have any other complaint and his physical examination of the patient was normal. Whole-body scan was acquired 3 h after the intravenous injection of 740 MBq of technetium-99m methylene diphosphonate ((99m)Tc-MDP). Distal sacrococcygeal region could not be observed during the visual analysis of the whole-body scan. Pelvic X-rays radiography and pelvic computed tomography of the patient, demonstrated hemiagenesis of the sacrum, which was consistent with type-2 sacral agenesis. Other structural abnormalities were not detected on the pelvic CT scan of the patient. This case is presented to demonstrate the rare congenital anomaly of sacral hemiagenesis causing empty pelvis appearance in the posterior projection of (99m)Tc-MDP whole body bone scan. This congenital anomaly could be associated with extensive abnormalities of the lower vertebrae, pelvis, and spine.

Brown tumors are rare but serious complications of renal osteodystrophy, and can be treated by parathyroidectomy or by pharmacological treatment of hyperparathyroidism. In addition to parathyroid lesions such as adenoma, hyperplasia, and carcinoma, brown tumors have been detected effectively by using dual phase Tc-99m sestamibi and Tl-201 chloride. We describe an unusual case of brown tumor at the manibrium sterni which shows marked increased Tc-99m sestamibi uptake on the initial scan, with decreasing tracer activity on follow-up scan indicating a response to antimetabolic therapy.

Inguinoscrotal herniation of the bladder is a rare clinical entity. The condition is often diagnosed incidentally or during the course of surgical repair of inguinal hernias. In a smaller number of cases, bladder hernia can be seen during nuclear medicine studies. We report a rare case of massive inguinoscrotal bladder herniation with ureter, causing urinary stasis on bone scintigraphy.

Unlabelled: When body position changes from erect to supine, the effect of gravity on the organs also changes and is a possible underlying mechanism for upward creep of the heart during SPECT acquisitions. We hypothesized that if we provide enough time for the organs to settle after a positional change, the range of this vertical motion causing reconstruction artifacts can be decreased. Our aim was to evaluate the effect that a 5-min bed rest on the imaging table before both rest and stress SPECT acquisitions would have on upward creep of the heart., Methods: Before both stress and rest SPECT acquisitions, the first 101 consecutive patients (group A) had a 5-min bed rest and the remaining 99 patients (group B) did not have any bed rest after they were positioned on the imaging table. Upward creep was detected by comparing the distance between the lower edge of the image and the lowest part of the heart silhouette on the last projection image of detector 2 and the first projection image of detector 1., Results: Upward creep was found in 53% (54/101) and 55% (56/101) of patients in group A and in 89% (88/99) and 86% (85/99) of patients in group B in stress and rest SPECT studies, respectively. Upward creep of the heart was decreased prominently in group A, and this decrease was statistically significant (p < 0.001)., Conclusion: We conclude that before SPECT acquisition, at least a 5-min bed rest on the imaging table significantly decreases vertical motion of the heart.

Rationale and Objectives: The aims of this study were to label the versatile amino acid l-lysine with (99m)Tc using 2,3-dimercapto-succinic acid (DMSA) as a chelator, and to assess its tumor imaging feasibility under in vivo and in vitro conditions, and finally to determine the subcellular biodistribution of this radiopharmaceutical., Materials and Methods: DMSA-l-lysine was chemically synthesized and labeled with sodium pertechnetate. Nuclear magnetic resonance (NMR) and mass spectral analysis of DMSA-l-lysine were conducted. Radiochemical purity was determined by thin-layer chromatography (TLC) and paper chromatography. Cellular uptake, competition and subcellular localization studies were performed in rat breast cancer cells (13762). In vivo studies of planar imaging and biodistribution studies were performed on female Fischer 344 rats. Medical Internal Radiation Dose (MIRD) dosimetry estimates were calculated., Results: Radiochemical purity (determined by radio-TLC and high-performance liquid chromatography) of these compounds was >95%. (99m)Tc-DMSA-l-lysine showed good uptake in in vitro cell culture assays and uptake was reduced in competition studies. (99m)Tc-DMSA-l-lysine accumulates in the nucleus as much as in the cytoplasm and it was also shown that accumulation of the (99m)Tc-DMSA-l-lysine in the nucleus increases as a function of a time. There was an increase in tumor-to-blood and tumor-to-muscle count density ratios. Tumor/background ratios were 5.75 at 1 hour and 6.87 at 2 hours. In vivo tissue distribution studies revealed that radiation dosimetry of blood-forming organs were within radiation dose limits., Conclusion: DMSA-l-lysine kits can be labeled with (99m)Tc easily and efficiently, with high radiochemical purity and cost-effectiveness. In vitro cellular uptake and scintigraphic imaging studies demonstrated the pharmacokinetic distribution and feasibility of using (99m)Tc-DMSA-l-lysine for tumor imaging.

Background: The diagnosis of endothelial dysfunction has been gaining clinical importance, but although endothelial function testing is available in the research setting, no technique yet exists that is simple, safe, reproducible and easily performed as a clinical screening method. The aim of this study was to design a new, scintigraphic method of imaging the flow-mediated dilation in the forearm, which represents the functional characteristic of endothelial dysfunction., Methods and Results: The study group comprised 118 subjects in whom left forearm ischemia was induced by inflating a sphygmomanometer cuff to supra systolic pressure for 4.5 min. Later, dynamic acquisition (2 s frame/min) was initiated after the injection of technetium-99m methoxy-isobutyl isonitril into the dorsal pedal veins. Equivalent regions of interest were drawn on both arms to detect total activity counts during 1 min and the perfusion ratios (left arm/right arm) were calculated. The left arm counts (22,203.3+/-12,372.7) were significantly higher than the right arm counts (9,980.9+/-5,931.9) (p<0.001). A significant decrease in perfusion ratios was noted in the hypertension and hypercholesterolemia groups. An increase in the number of risk factors caused an insignificant decrease in perfusion ratio (p=0.346)., Conclusion: Non-invasive evaluation of endothelium-dependent vasodilation by semiquantitative scintigraphic method using radioactive perfusion tracer provided promising results.

Between 1984 and 2002, pulmonary metastases were detected in 42 (4%) out of 1,023 patients with differentiated thyroid carcinoma (DTC) in our department. The age at diagnosis ranged from 6 to 77 years. Lung metastases were diagnosed by both increased thyroglobulin (Tg) levels and positive uptake of iodine-131 on scans, and/or positive radiological findings. The primary tumours were histologically classified as papillary (30 patients), follicular (nine patients) and poorly differentiated (two tall cell, one insular carcinoma). The duration of follow-up ranged from 24 to 228 months. The end-results of the (131)I therapy were evaluated. The treatment of choice was (131)I therapy of metastases after total thyroidectomy plus lymph node dissection (if lymph node metastases were present). Applied single and total (131)I activities were 1.8-10.4 GBq and 5.5-43.7 GBq, respectively. Lung metastases were present at the time of diagnosis in 30 patients and developed during the follow-up period in the remaining 12. Twelve patients with extensive metastases died of thyroid carcinoma and another died due to secondary malignancy (malignant mesothelioma). Ten patients with lung metastases remain completely free of disease and are probably cured, while another seven were stable at the time of study. Three- and five-year survival rates were 86% (36/42) and 76% (32/42), respectively. To define the diagnostic value of high-resolution computed tomography (HRCT) and identify the distinctive features of lung metastases from DTC, 22 patients were further examined with HRCT within 2 weeks of the initial diagnosis of lung metastases and the results were compared with chest X-ray findings. HRCT detected metastases in 10 out of 14 patients with a normal chest X-ray and confirmed metastases in all patients with positive (n=5) and suspicious (n=3) chest X-ray. HRCT did not show any abnormalities in four patients with positive lung uptake on (131)I whole-body images. Stage of disease, existence of distance metastases other than to the lung, and HRCT characteristics were significant prognostic variables. Lung metastases from DTC can be cured with (131)I therapy in a considerable number of patients, especially when they are not associated with other distant metastases; they should therefore be treated at an early stage. HRCT clearly improved diagnostic ability in the evaluation of lung metastases compared with chest X-ray and should be the primary method when radiological correlation is needed. The main, and new, finding of the study is that HRCT not only improves diagnostic ability but is also of prognostic value.

Whole body imaging with radioiodine can detect functioning metastases, which can often be effectively treated with appropriate amounts of radioiodine. Non-physiologic I-131 uptake detected on images is usually interpreted as suggesting functioning thyroid metastases. However, extra-thyroidal I-131 accumulation does not always imply thyroid cancer metastases and has been reported on many occasions, including various non-thyroidal neoplasms, and contamination by body secretions. In order to avoid unnecessary therapeutic interventions it is extremely important to properly distinguish false-positive sites of I-131 localization. Three patients with unusual radioiodine contamination patterns, either presented for the first time or rarely presented in the existing literature, were reported. Reported cases consist of contamination in hair (due to styling hair with sputum), contamination in neck (due to drooling during sleep) and, contaminated chewing gum. False positive contamination sources were clarified by careful examination of patients and further images when necessary.