armaghan fard-esfahani

Neurofibromatosis type 1 (NF1) is a prevalent inherited condition, having a risk for malignant conversion to malignant peripheral nerve sheath tumor (MPNST). Our study objective was to assess the effectiveness of [18F]FDG PET/CT and Magnetic Resonance Imaging (MR) in identifying early transformation in pediatric patients, given the limited data available in existing literature. In this study children with suspected or confirmed NF1 who underwent [18F]FDG between January 2007 and April 2024 were included in a retrospective cross-sectional analysis. Exclusion criteria was follow-up periods shorter than one-year post [18F]FDG results. The study included 13 patients (6 females, 7 males), with a median age of 11 years, and a total of 16 lesions. Only two lesions were confirmed by biopsy to have undergone malignant transformation into a MPNST. Although the findings varied, [18F]FDG imaging was able to anticipate the malignant transformation only in one of these two cases. Due to the limited sample size, definitive conclusions could not be provided. We were unable to propose a specific SUVmax cutoff to predict the malignant transformation of neurofibromas in children with NF1  disease.

[68Ga]Ga-PSMA PET/CT has gained acceptance for localizing local and distant metastases; However, urinary activity remains a confounding factor in interpreting local metastases. The aim of this study was to evaluate the diagnostic value of two-phase protocol (i.e., early and regular imaging, TPP) in comparison with delayed optimized protocol (i.e., combined regular and delayed post hydration and diuresis images, DOP) to detect locoregional prostatic metastases. Forty-one prostate cancer patients referred for staging (n = 12) or the evaluation of rise in PSA level in prostate cancer (n = 29) were prospectively assessed. In this study, each patient received an early 5-10 min image from pelvic region for two bed position, regular (RP) (60 min) and finally delayed static images. The scan findings were characterized as positive, negative or equivocal. The diagnostic significance of TPP was compared with DOP for prostatic, periprostatic, locoregional lymph nodes and pelvic bone involvement. The diagnostic agreement between DOP and TPP for prostate/prostate bed lesions was comparable with the agreement of DOP and RP (Kappa: 0.78, p < 0.001) vs. (Kappa: 0.8, p value < 0.001). TPP in comparison with RP, had superior sensitivity for prostate/prostate bed lesions (95% vs. 80%). The sensitivity for lymph node metastases, extraprostatic extension and osteometastases was identical between the two protocols. TPP has the potential to replace DOP for the evaluation of prostate/prostate bed lesions; however, there remains instances where delayed imaging is helpful in characterizing the anatomic abnormality especially in the lymph node region.

Distinguishing the cellular origin of lung cancer is essential for tailored patient care. This pioneering pilot study explores the synergy of 1H-Magnetic Resonance Spectroscopy (1H-MRS) and 2-[18F] fluoro-2-deoxy-D-glucose positron emission tomography/computed tomography ([18F]FDG PET/CT) in the differentiation of primary squamous cell carcinoma (SCC) of the lung from Hodgkin's lymphoma (HL) metastases. Ethically approved, the study enrolled 21 participants with confirmed lung lesions (10 SCC, 11 HL). [18F]FDG PET/CT and 1H-MRS were conducted, and analyses were performed to assess diagnostic potential. Significant differences in [18F]FDG PET/CT parameters (SUV max BSA, SUV max LBM, and ID%) between SCC and HL were observed. Metabolite concentrations (Cho, Lac, Cr) from 1H-MRS also exhibited distinctions. Correlations between PET values and metabolite concentrations hinted at links between glucose metabolism and molecular composition. This study presents an innovative approach, integrating 1H-MRS and [18F]FDG PET/CT to distinguish primary from metastatic lung lesions. The results hold promise for improving non-invasive diagnostic accuracy and guiding targeted therapies. Future research should validate these findings and explore the potential for clinical integration.

Effective management of radioiodine (RAI)-refractory differentiated thyroid cancer is a challenge due to limited treatment options. Multikinase inhibitor therapy including sorafenib has been an optional treatment in recent years. This study aims to compare the clinical benefit rate, progression free survival, and quality of life between patients who received limited dose of sorafenib (200-400 mg per day) as opposed to the control group.

Twenty-two patients who received sorafenib and twenty-three cases in the control group were studied for two years. Baseline variables were comparable between two subgroups. The results of diagnostic imaging methods were also taken into consideration. Quality of life was measured using the EORTC (European Organization for Research and Treatment of Cancer) quality of life questionnaire.

Based on the RECIST (Response Evaluation Criteria in Solid Tumors) criteria, clinical benefit rate was 77.3% and 47.8% in sorafenib and control subgroups respectively (p value=0.042). The median of progression free survival for the sorafenib subgroup was 24 months and in the control subgroup was 22 months (p value=0.020). In a comparison between two groups regarding their quality of life, all subscales were statistically insignificant between the two groups except for the symptom subscale (p value=0.001).

Low-dose sorafenib maintenance therapy is an effective treatment option in RAI- refractory differentiated thyroid cancer with the main effect of stabilizing the disease. Except for unpleasant but tolerable adverse effects, this treatment has no significant negative influence on the quality of life as far as the physical, role, cognitive, emotional, financial and social functions are concerned.

Thyroid cancer is the most common endocrine malignancy in the world; however, these patients usually experience a high survival rate if they receive appropriate and timely treatment. Meanwhile, patients classified as having differentiated thyroid cancer with high thyroglobulin and negative iodine scan [Differentiated thyroid cancer with thyroglobulin elevation and negative iodine scintigraphy (TENIS)] are always considered a diagnostic-therapeutic challenge.

We conducted a comprehensive literature search of published papers in the PubMed/MEDLINE database regarding nuclear imaging in differentiated thyroid cancer with thyroglobulin elevation and negative iodine scintigraphy. We included all human studies in this field.

In this review, we examined four major groups of imaging studies aimed at identifying GLUT, SSTR, PSMA and FAP receptors in patients with TENIS. The diagnostic rate of 2-[18F]FDG PET/CT in these patients has been reported as 63-81% based on various studies. Also, [68Ga]Ga-DOTATATE PET/CT, [68Ga]Ga-PSMA PET/CT and [68Ga]Ga-FAPI PET/CT scans have shown good results in these patients.

[68Ga]Ga-FAPI PET/CT imaging has the highest diagnostic rate among these patients. Given the theranostic capability of FAPI and the numerous complications and limited inclusion criteria for treatment with tyrosine kinase inhibitors, it has been the next step in the treatment of patients with TENIS. Therefore, more extensive studies in this field are warranted.

2-[18F]fluoro-2-deoxy-D-glucose-positron emission tomography/computed tomography (2-[18F]FDG-PET/CT) is implemented in papillary thyroid cancer (PTC) patients with elevated Thyroglobulin (Tg) and negative Iodine-131 whole-body scan (131I-WBS). Here, we evaluated the impact of TSH stimulation after levothyroxine withdrawal on the detection rate of 2-[18F]FDG-PET/CT. A prospective study was performed on 60 PTC patients, presented with negative 131I-WBS and elevated or unjustifiably high Tg. 2-[18F]FDG-PET/CT was performed in 30 patients while they were on levothyroxine therapy (unstimulated-TSH [uns-TSH]) and after Levothyroxine withdrawal in the other 30 patients (stimulated-TSH [s-TSH]). Results of the two groups were compared using nonparametric tests. Receiver operating characteristic curve was used to find Tg cutoff values for predicting positive scan results. Overall, 2-[18F]FDG-PET/CT was positive in 63.3% of the patients, 80% (24/30) in s-TSH and 46.7% (14/30) in uns-TSH group. The detection rate was higher in s-TSH group (p=0.007). It was still significant in multiple regression analysis (p=0.041). In uns-TSH group, 2-[18F]FDG-PET/CT was more often positive in patients with higher uns-Tg level (p=0.002). An uns-Tg level of ≥19.00 ng/mL predicted positive results with the sensitivity of 0.786 and specificity of 0.750 (area under curve=0.819). Although statistically insignificant (p=0.055), s-Tg was higher in patients with positive 2-[18F]FDG-PET/CT studies in the s-TSH group. No relation was demonstrated between TSH and anti-Tg-antibody levels and 2-[18F]FDG-PET/CT positivity. TSH-stimulation after levothyroxine withdrawal might enhance the detection rate of 2-[18F]FDG-PET/CT in PTC patients. Additionally, 2-[18F]FDG-PET/CT is more often positive in patients with higher Tg levels.

Non-cutaneous malignant melanomas (NCM) are rare malignancies. Due to their nonspecific symptoms, they present later in life. The value of FDG PET/CT in this group of patients is not clear. The aim of this study is to assess the role of FDG PET/CT in the management of NCM and its prognostic implication.

We retrospectively selected twenty-three patients with a diagnosis of NCM evaluated with FDG PET/CT in Shariati hospital between 2019 and 2021. The PET/CT data were reviewed and compared with available conventional imaging findings. Five patients died within five months. The surviving patients were followed within a time interval of 7 to 27.5 months after their PET/CT study, regarding their disease status.

Among 23 patients (8 ocular, 5 sinonasal, 3 pharyngeal, 2 anorectal, 2 vulvovaginal, and 3 unknown primaries), PET/CT was able to detect residual primary disease, assess treatment response, and reveal or exclude metastases. Additional lesions compared to conventional imaging were found in five, while in one with brain metastases PET/CT was unable to detect lesions on MRI.  Thirteen patients had negative PET/CT finding of which 11 (85%) did not have remarkable finding on follow-up. Metastatic disease was recognized in eight. Patients with extensive metastases on FDG PET/CT had a poorer outcome.

Similar to cutaneous melanoma, PET/CT is valuable in the management of NCM patients and is superior to conventional imaging modalities, with the exception of brain metastases. Patients with negative PET/CT findings have a better outcome as opposed to patients with significant positive PET/CT findings.

Primary cardiac osteosarcoma is a very rare malignancy with a high incidence of local recurrence and systemic metastasis, contributing to the poor prognosis. Radiological modalities are commonly used for the evaluation of cardiac masses. 2-[18F]fluoro-2-deoxy-D-glucose ([18F]FDG) positron emission tomography/computed tomography is a valuable whole-body imaging modality in the evaluation of most subtypes of sarcomas. The value of [18F]FDG PET/CT is not well-established in primary cardiac osteosarcoma, and it has rarely been documented in the literature. Here, we report the findings of [18F]FDG PET/CT in a case of a 38-year-old man with primary cardiac osteosarcoma, which clearly demonstrates the recurrent lesions in the myocardium.

Adrenal lesions are commonly observed during 18F-FDG PET/CT studies. Although, most of these lesions are considered benign, an important consideration in oncologic patients is metastasis. Benign lesions, such as adenomas usually present with low 18F-FDG uptake, although overlap with malignant lesions exist and clear SUV cut-off for distinguishing adrenal adenomas has not been established. Different criteria have been proposed to further characterize adrenal lesions, as benign or metastatic. Conventional imaging modalities have additional value when the degree of uptake is equivocal. In this review, we go through some of the common adrenal lesions, as well as discerning features that favor either benign or malignant etiology.

Management of locally advanced colon cancer metastases is challenging and operation carries an increased risk of morbidity and mortality. The knowledge of exact sites of involvement can aid the surgeon to make a decision regarding complete resection or palliative therapy. PET/CT scan is an advantage in this setting because metabolic alterations often precede the anatomic changes; moreover, it can show unexpected metastases. In addition, PET/CT scan can differentiate adhesions and scar from local invasion of tumor.  We report a rare case of locally advanced colon cancer metastases to mesentery with extension to liver, chest wall and mediastinum depicted on PET/CT scan. The patient was treated with resection of the involved sites. The pathology report confirmed a poorly differentiated adenocarcinoma mainly involving the mesentery with extension to surrounding organs including the liver. Unfortunately, the patient’s condition deteriorated following surgical intervention. Although there is a trend toward complete resection of primary tumor and involved sites in patients with metastatic colon carcinoma to improve overall patient survival by eliminating any residual disease, in more advanced stages of the disease, palliative therapy might be the preferred approach. PET/CT has invaluable complimentary role to improve surgical planning in advanced oncological situations.

Rosai Dorfman disease is a rare form of nonlangerhans cell histiocytosis, presenting with extensive lymphadenopathies. Treatment in most cases of nodal disease, involves close observation; however, extranodal involvement requires a more definitive treatment strategy. Herein, we report a case of extensive Rosai Dorfman disease in a 43-year-old woman presenting for evaluation of treatment response by 18F-FDG PET/CT after frequent relapses and disease progression. In addition to extensive lymphadenothapies in cervical, supraclavicular, superior mediastinum, axillary, abdominopelvic and inguinofemoral regions, the patient had metabolically active bone and subcutaneous lesions which were not previously recognized. Following this 18F-FDG PET/CT study, the patient management was changed to sirolimus and prednisolone. To choose the best treatment option for Rosai Dorfman patients, knowledge of the full extent of disease is important. Compared with conventional imaging, 18F-FDG PET/CT has the advantage of being a whole-body imaging modality and can recognize disease involvement prior to any anatomical changes.

Evaluation of calcified metastatic lesions by conventional imaging can be challenging. Ovarian cancer metastases can present with calcification which might increase in size and number following therapy. It is not entirely clear whether these calcifications are associated with tumor response or disease progression. Calcified lesions which do not change in size or configuration are particularly problematic when assessed by RECIST criteria. Positron emission tomography (PET)/computed tomography (CT) is of particular value as it demonstrates the metabolic activity of the calcified lesions, in addition, it might reveal metastases in unexpected sites. We report a case of serous papillary ovarian cancer with extensive abdomino-pelvic calcified metastases referred for evaluation of therapy response. Despite being reported as stable disease on CT evaluation, we observed increased metabolic activity in the calcified lesions both on CT-attenuation corrected and non-attenuation corrected images, which was indicative of inadequate response to therapy. PET/CT is an ideal modality in follow-up of patients with ovarian cancer presenting with calcified metastatic tumoral deposits.

Differentiatedthyroid carcinoma (DTC) constitute approximately 90% of all thyroid tumors with an overall excellent prognosis. However, there is a small group of patients with a more aggressive form of disease, usually associated with certain poor prognostic factors. Using our large database of patients with DTC, the current study aims at identifying some of these factors. 

This retrospective study was based on the registry of patients with non-medullary thyroid carcinoma. Data were collected on the clinical, laboratory, and outcome characteristics of 501 patients followed at our department.

On multivariate analysis, the following variables were predictive of persistent disease: less than total thyroidectomy, residual disease on the post treatment whole body radioiodine scan (WBIS), higher received radioiodine activities, and higher levels of baseline stimulated thyroglobulin (Tg) and thyroid stimulating hormone (TSH). The greatest predictive value for the persistent/recurrent disease was attributed to the presence of residual disease on the post-treatment WBIS (odds ratio (OR): 33.72, 95% confidence interval (95% CI): 18.17-62.57), followed by type of surgical procedure (OR: 8.92, 95% CI: 2.90-27.39), radioiodine ablation dose (OR: 4.03, 95% CI: 1.56-10.39), stimulated baseline Tg level (OR: 2.79, 95% CI: 1.53-5.08) and finally, the stimulated baseline TSH level (OR: 2.21, 95% CI: 1.08-4.519).

In patients with DTCs, surgical procedures other than total thyroidectomy, presence of residual disease on the post-treatment WBIS, higher received radioiodine activities, higher baseline stimulated Tg and TSH levels are associated with a higher probability of having persistent disease and can be used in conjunction with other disease characteristics to reach proper decisions with regard to treatment and follow-up.

Multiple myeloma (MM) is a clonal B-lymphocyte neoplasm of terminally differentiated plasma cells. Imaging modalities which allow the recognition of the effects of myeloma cells on the skeletal system have been utilized for a long time. Herein, we represent a patient with generalized osteoporosis and hypercalcemia, who was referred for parathyroid scan, in whom the widespread bone marrow technetium-99m-methoxy-2-isobutylisonitrile (99mTc-MIBI) uptake suggested the presence of a bone marrow involving pathology, which turned out to be multiple myeloma on bone marrow biopsy. The current case report highlights the importance of 99mTc-MIBI scintigraphy, with a relatively low cost and better accessibility compared with other high sensitivity modalities such as PET-CT, to be used to demonstrate multiple myeloma bone marrow involvement, which could incline physicians to consider 99mTc-MIBI scintigraphy as a complementary diagnostic tool for multiple myeloma.

Myocardial perfusion imaging (MPI) is an important imaging modality in managing patients with cardiovascular disease. MPI has a significant role in diagnosis and management of cardiovascular disease; however it is subjected to different artifacts. Combining pharmacologic stress with submaximal exercise reduces side effects, improves image quality, and enhances the detection of ischemia, compared with suboptimal exercise or vasodilator stress alone.
97 patients (62 males and 35 females) which were randomly allocated into two groups were studied using gated single-photon emission computed tomography (SPECT) imaging. The patients were randomly allocated into two different groups: dipyridamole or dipyridamole combined with submaximal exercise group. Subsequently, they were imaged at 15, 60, 120, and 180 minutes after radiotracer injection.
97 patients with an average age of 57.1 were compared 15, 60, 120 and 180 minutes after radiotracer injection. Comparing dipyridamole and dipyridamole submaximal exercise group a significant difference in target areas (myocardium, inferior and lateral wall) count ratio to both liver and colon count ratio was observed (P A protocol that combines submaximal exercise with dipyridamole stress is highly effective in improvingthe average count ratio of myocardial walls compared to visceral activity.

The present study was aimed to assess the diagnostic performance of the two imaging methods of 131I-metaiodobenzylguanidine (131I-MIBG) and 99mTc-hydrazinonicotinyl-Tyr3-Octreotide (99mTc-HYNIC-TOC) in diagnosis and localization of pheochromocytoma and neuroblastoma.
This study was conducted on 40 consecutive patients with positive pathological results for pheochromocytoma or neuroblastoma. The patients underwent both I-131 131I-MIBG and octreotide scintigraphies. By using the findings of cytopathology, biomarkers, imaging studies, as well as the results of a six-month follow-up, a composite reference standard (CRS) was defined as the diagnostic gold standard.
Overall comparison of these two agents revealed higher sensitivity for 131I-MIBG than octreotide study both in patient-based analysis (100% vs. 80.9%, respectively), and lesion-based analysis (94.4% vs. 80.56%, respectively). In pheochromocytoma 131I-MIBG and octreotide are both highly sensitive (100%), while 131I-MIBG is more specific (100% vs. 87.5%). In neuroblastoma, 131I-MIBG is more sensitive than octreotide (100% vs. 81.25%).
Our study shows superiority of 131I-MIBG over octreotide scanning in detection of both neuroblastoma and pheochromocytoma lesions. However, a combination of these two diagnostic tools provides more complete information on the nature and the site of lesions. The first suggested study is 131I-MIBG scanning, and if it is not available, or detecting precise location of all lesions is of concern, octreotide scanning can be helpful as a complementary study. Furthermore, in case of octreotide positive lesions, follow-up can be performed with octreotide scan with less radiation burden.

Soft tissue metastases are extremely rare in differentiated thyroid cancers. We hereby present a man with a history of papillary thyroid cancer (PTC) at the age of 46, who was referred to cancer Institute due to raised serum thyroglobulin (Tg) and a new mass in the thigh. Imaging studies were suggestive of recurrence of the disease in the tumor bed, neck nodes and lungs, and also a mass in his left thigh, based on positron emission tomography (PET) scan, without radioactive iodine uptake. The excision of the mass revealed metastatic PTC. After management of symptomatic local recurrence with external beam radiotherapy (EBRT), he received sorafenib. After three years he is doing well and serum Tg is stable.

High-dose radioactive iodine therapy in differentiated thyroid cancer (DTC) may adversely affect the salivary gland function. This study is aimed to evaluate the effect of radioactive iodine (RAI) with dose of 100 mCi in DTC patients compared to lower doses of less than 30 mCi in hyperthyroid cases. Fifty four patients (13 men and 41 women) age: 42.3±14.3 (21-71) years were enrolled in the study. Twenty seven hyperthyroid cases received less than 30 mCi of I-131 for the treatment, and 27 DTC patients were treated with 100 mCi of I-131. All patients underwent Tc-99m pertechnetate scintigraphy before and three months after radioiodine therapy. Salivary gland excretion fractions (EF) were compared between groups. A decrease of more than 5% in EF was considered significant. The total frequency of salivary dysfunction was 41.7%. In patients received a dosage of 100 mCi of I-131, this frequency was 49.1%, while with less than 30 mCi, it was 34.3% (p<0.01). The right parotid gland was affected more than the left following 100 mCi treatment. Risk ratio of salivary gland involvement in high-dose versus low-dose group was significant (risk ratio=1.04-1.98, CI (95%); p=0.019). However, there was no significant difference in symptom presentation, i.e. xerostomia between two groups. RAI therapy may cause salivary gland dysfunction and this effect is more frequent in DTC patients with higher dose of 100 mCi compared to hyperthyroid cases with lower doses of less than 30 mCi.

Asymptomatic diabetic patients are at increased risk of cardiovascular complications. Myocardial perfusion scan may be effective in risk evaluation in this population. 106 asymptomatic diabetic patients (age: min: 37, max: 82, mean: 57.73±8.88), including 56 females (52.8%) and 50 males (47.2%) were enrolled in the study. Myocardial perfusion scintigraphy was performed by Gated Single Photon Emission Computed Tomography (Gated-SPECT) method. Perfusion and function status was evaluated by qualitative and semi-quantitative parameters. By visual analysis totally 40 out of 106 patients (37.7%) showed abnormal scan. From which, 26(24.5%) showed involvement in one, 13(12.3%) in two, and 1(0.9%) in all three vessel territories. By semi-quantitative method, from 103 patients, 28 (27.2%) were abnormal and 75 (72.8%) were normal. From all the asymptomatic diabetic patients, 11 patients (10.4%) had dilated left ventricles. Transient Ischemic Dilation (TID) was noted in 10 patients (9.4%), and Transient Right ventricle visualization in 7 patients (6.6%). Heart failure (EF<45%) was observed in 14% of asymptomatic diabetic patients. From underlying factors, long duration of diabetes disease correlated to abnormal myocardial perfusion imaging (MPI) findings (Odds Ratio: 2.77; CI: 1.07-7.12). Severe coronary artery disease leading to the pattern of severe ischemia or infarction in MPI, was significantly higher in men than women (P=0.05). Also smoking correlated with higher involvement of LAD coronary artery (P=0.011) and as compared with RCA territory (P=0.079). In asymptomatic diabetic patients myocardial perfusion scintigraphy can be used in early diagnosis of coronary artery disease (CAD) and can be suggested as screening study in these patients.

Bone metastases are the most common cause of cancer-related pain in various primary malignant tumors, most often, breast and prostate. 188Re-hydroxyethylidene diphosphonate (188Re-HEDP) is a new and less expensive bone seeking radiopharmaceutical with favorable physical characteristics of the radionuclide such as short half life of 16.9h, maximal β energy of 2.1 MeV with a 15% γ-component of 155 keV and easily available from an in-house 188W/188Re generator. The aim of this study is to evaluate the therapeutic efficacy and safety profile of bone palliative therapy following administration of 188Re-HEDP. Twenty patients with painful metastatic bone lesions secondary to breast, prostate, multiple myeloma, ampulla of vater and lung cancers received 1 mCi/kg of 188Re-HEDP. Four hours after treatment, post-therapy scintigraphy was performed. All patients were interviewed using a standard set of questions (visual analogue scale: VAS) concerning their pain relief before, and after therapy at weekly intervals for the first month and every 2 weeks for the following 4 months. The general condition of the patients was also evaluated by Karnofsky-index and ECOG (Eastern Cooperative Oncology Group) performance status. Hematologic profiles were recorded before treatment and every two weeks up to 8 weeks after treatment. Overall pain relief was found in 68.8% of patients. Decreased from 8.37±2.12 to 5.68±2.98 at VAS was observed 4 weeks after treatment. The osteoblastic lesions (breast and prostate) showed rather similar response to the treatment. Mean platelet counts decreased in 6th week and returned to baseline level in 8th week. One patient showed grade III leukopenia without any serious complication. 188Re-HEDP is an effective radiopharmaceutical for metastatic bone pain palliation therapy. Side effects include mild and transient thrombocytopenia and leucopenia and no life threatening side effect is observed.

The main purpose of this study was to compare transient ischemic dilation (TID) ratios in SPECT-low dose CT and SPECT Myocardial Perfusion Imaging (MPI) by application of different quantitative programs and quantify the possible shift in the upper normal limits of TID ratio in the SPECT-CT MPI. 149 Patients with low pre-test probability for coronary artery disease (CAD), based upon Diamond and Forrester method entered the study. Each patient underwent both attenuation correction (AC) SPECT-CT MPI and non attenuation correction (NAC) SPECT MPI (two day Tc-99m sestamibi stress-rest protocol). Normalcy rates were also calculated and compared. The comparison was based on both visual interpretation and quantitative analysis. In the low pre-test probability group visual interpretations lead to a statistically significant improvement in normalcy rate in the SPECT-CT acquisition compared to the SPECT MPI. Regardless of the stress type and software programs used, no significant difference was noted in the upper normal limits of the TID ratios between the AC and NAC acquisitions. The study showed superiority of SPECT-CT MPI to SPECT MPI in terms of normalcy rate. We also propose new upper normal limits of TID ratios for different sets of acquisition-gender-stress modality-software programs.

We intended to assess the accuracy of re-expressed Modification of Diet for Renal Disease (MDRD) and Cockcroft-Gault (CG) equations to estimate glomerular filtration rate (GFR) in chronic kidney disease in two different etiologies of acute renal failure (ARF): acute tubular necrosis (ATN) and acute glomerulonephritis (AGN). Patients admitted for ARF or the patients complicated with ARF during the course of their hospitalization were enrolled to the study (n=21; 14 females and 7 males; 11 ATN and 12 AGN). When the plasma creatinine reached a steady state (DPSM) using 99mTc-DTPA. GFR was also estimated by MDRD (GFRMDRD) and CG (GFRCG) equations. The patients aged 44.8±19.5 years and weighted 67.8±10.7kg. GFRDPSM (32.9±14.7 ml/min) was statistically different from the GFRMDRD (11.6±8.2 ml/min; pCG was lower than GFRDPSM in patients with either ATN (16.5±12.5ml/min and pDPSM and GFRMDRD (r=0.34; p=0.13) but GFRDPSM and GFRCG values were correlated (r=0.48; p=0.03). Out of subjects with GFRDPSM >30, 92.3% had GFRMDRDCG Our results indicate that MDRD and CG equations were substantially inaccurate in patients with ARF. More precise methods of GFR evaluation is recommended in these patients.

Bone is one of the most common sites of metastatic disease in malignancies. Many of the cases are asymptomatic and may be diagnosed in primary or secondary follow-up، but in symptomatic cases pain is the prominent symptom which is mostly exaggerated at nights. The improved survival of cancer patients with bony metastases in recent years، specially in breast and prostate cancer، has given a greater importance to the careful choice of treatments in this setting. This can lead to a better quality of life، lower treatment cost، prevention of disabilities، less delay in primary cancer therapies، and decrease of life-threatening events for the patients. Here we review the metastatic disease of the bone and its treatments، with emphasis on local and systemic radiation therapy. Current literature about bone metastasis and its treatments was reviewed through a search of available databases on internet for papers published in 1995-2013. Special attention was given to the research trials and studies performed by the authors on this setting. Treatment of bone metastases consist of analgesics، radiotherapy، surgery and bisphosphonates. Control of bone metastases is a challenging process، necessitating a multi-disciplinary approach and teamwork between the treating physicians. Radiotherapy is the most useful modality for this purpose in oncology، given both as a local and systemic therapy. We hope that this review would be able to help in choosing the best treatment option for this common palliative situation in Iranian cancer patients.

Ubiquicidin (UBI) [29-41] is a synthetic cationic antimicrobial peptide that preferentially binds to bacterial cell membrane at the site of infection. We aimed to assess diagnostic value of 99mTc-UBI [29-41] as a radiopharmaceutical in differentiation of bacterial infection from sterile inflammation in suspected orthopedic implants. Nine patients suspected for orthopedic implant infection, all males with the mean age of 41.6 ± 20.9 years, were studied. A dose of 10 MBq/Kg (range: 555-740 MBq) 99mTc-UBI [29-41] was injected intravenously. A dynamic study followed by static whole body imaging at 30, 60 and 120 min post-radiotracer injection was acquired. Periprosthetic tissue culture was considered the closest test to a gold standard for diagnosing infections and scintigraphic scans were categorized as true- or false-positive and true- or false-negative, considering the bacterial culture as the gold standard. No adverse reaction was observed during or after the radiotracer injection days. There were five true positive, four true negative and no false positive and false negative scans. Sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) were all calculated as 100%. We found a high diagnostic accuracy for 99mTc-UBI [29-41] scintigraphy in differentiation of bacterial infection from sterile inflammation in suspected orthopedic implants. Therefore, 99mTc-UBI [29-41] scintigraphy might be potentially recommended as a safe and promising imaging modality in these settings. However, further studies on a larger number of patients and different pathologies are still needed.

Almost all malignant tumors have the potential to eventually produce bone metastasis. The aim of the current study was to report the distribution pattern and imaging characteristics of bone metastases detected by conventional whole body bone scintigraphy in patients with different types of malignancies and to assess their relationship with the complaint of bone pain. As a cross-sectional study, 146 consecutive patients with histologically proven cancer who were referred for the assessment of possible bone metastatic involvement were investigated by 99mTc-Methylene Diphosphonate (MDP) whole body scintigraphy. A total of 146 patients (79 male and 67 female; mean age: 59.59±11.95) were enrolled, of which 71 (48.6%) patients had prostate cancer, 61 (41.8%) breast cancer, 6 (4.1%) gastric malignancy, and 8 (5.5%) miscellaneous cancers. The most frequent sites of bone metastases (vertebrae, pelvis and sternum) demonstrated more intense radiotracer uptake. Most of patients (58.5%) with bone metastasis due to breast cancer reported no localized bone pain. Also in the subgroup with prostate cancer, no significant association was noted between the site of bone metastases and location of the pain perception in most of the skeletal zones. Bone scintigraphy (by determining the specific pattern of bone metastases in different tumor types) may help physicians provide better care for patients who suffered from metastatic cancer. On the other hand, in view of the fact that no reliance can be placed on clinical symptoms and the patient's report of bone pain, bone scintigraphic data can be included in the follow-up evaluation of patients suspected to have bone metastasis, even in the absence of bone pain.