Tc-99m MDP Bone Research Articles

Lessons learned from 15-year of radionuclide bone scan in cancer context at Yaoundé General Hospital (Cameroon) (+ Running poster)

In our setting, patients come lately to cancer treatment centres. The introduction of radionuclide scan in 2004 has had a great contribution to the diagnosis of bone metastases. To take stock of fifteen years of bone exploration in cancer context in our setting. A 15-year retrospective study with 1278 patients who performed each a radionuclide bone scan for different cancers, from 2004 to 2019 in our national reference centre. All 99mTc-MDP bone scans were performed on a Siemens® gamma-camera with a low energy high-resolution collimator. Collected data were analysed using SPSS® software with significant P -value < 0.05. Ages ranged from 15 to 92 years with a mean of 55.9 ± 15.9 and a 1.34 sex ratio. The modal age group was 50 to 70 years (39.36%). The major cancers were prostate (49.68%), breast (31.77%) and cervix (5.16%) cancers. The average duration since the diagnosis of cancer was 25.7 months. Positive bone scans accounted for 40.77% and the presence of bone metastases revealed an unknown cancer in 9.79%. The main affected sites were chest (79.27%), spine (78.31%) and pelvis (71.01%). In 26.49% of positive cases, there was no clinical sign of bone disease. According to Soloway and SWOG's classifications, the prognosis was poor in 70.06% and 66.22%, respectively. Prostate cancer was the most pejorative and cervix cancer was the one with the best prognosis ( P = 0.0014). Bone metastases are present in almost half of cases of cancers, even in absence of clinical signs. Axial bones, mainly chest, spine and pelvis, are the preferential sites. Ten percent of cancers are revealed by bone metastases. In 2/3 of cases, the prognosis is pejorative, especially for prostate cancer. We recommend that clinicians become more aware of the systematic search of bone extension as soon as the cancer is diagnosed.

Efficacy and safety of 177Lu-DOTMP in palliative treatment of symptomatic skeletal metastases: a prospective study.

Bone-seeking radiopharmaceutical 177Lu-DOTMP with favorable pharmacokinetics in the preclinical studies has been evaluated for its role in reducing bone pain and improving quality of life (QOL) in patients with symptomatic skeletal metastases. Patients with painful widespread skeletal metastases documented on 99mTc-MDP bone scintigraphy were intravenously administered 37 MBq/kg of 177Lu-DOTMP. Visual analogue score (VAS), analgesic score, European Cooperative Group of Oncology (ECOG) and the European Organization of Research and Treatment of Cancer QLQ-C30 of all the patients were assessed at baseline and posttherapy follow-up. Adverse effects were graded according to NCI-CTCAE V 5.0. Twenty-seven patients with painful widespread skeletal metastases (men 18; median age 61 years; range: 18-81) were studied for their responses as complete response, partial response, minimal response, no response and pain progression based on VAS and analgesic score. Overall response was seen in 77.8% of patients (complete, partial and minimal in 29.6, 33.3 and 14.8%, respectively) with significant improvement in median VAS and mean analgesic score at 2 months posttherapy from baseline (P < 0.001). The best response was seen in patients with breast cancer (100%) followed by prostate cancer (81%) and lung cancer (28%). Improvement in QOL was noted in 40% of patients, with change in ECOG score from 3.07 ± 0.67 at baseline to 2.6 ± 0.9 at 2 months posttherapy. Grade 2/3 anemia, grade 1/2 leukopenia and grade 1/3 thrombocytopenia were seen in 37, 11.1 and 18.5% patients respectively in the follow-up. 177Lu-DOTMP appears to be efficacious treatment for bone pain palliation with improvement in QOL though less effective in patients with lung cancer. The patients had transient mild-moderate hematotoxicity.

99mTc-MDP 3-Phase Bone Imaging in 3 Cases of Pigmented Villonodular Synovitis.

Pigmented villonodular synovitis (PVNS) is a rare proliferative synovial benign disorder, which is characterized by villonodular hyperplasia of joints, tendon sheath, and synovium; invasion of adjacent tissue; and sometimes visible hemosiderin deposition. Studies regarding bone scan findings of PVNS were relatively limited. Here, we report our findings on 99mTc-MDP 3-phase bone scan with SPECT/CT images on delayed phase in 3 patients with joint PVNS.

Pelvic Kidney Mimicking Skeletal Metastasis on Bone Scan- Interesting Image

A 57-year-old female patient underwent left breast-conserving surgery with sentinel lymph node biopsy for Left breast carcinoma (stage IIA). The patient had hypertension and diabetes mellitus. Other findings include multiple hepatic cyst, bilateral renal cysts and uterine myoma. She had no significant renal symptoms and her liver &amp;renal function test were normal.She was sent for Technetium-99m-methylene diphosphonate (99mTc-MDP) bone scan. There was a large area of intense tracer concentration in the region of right sacro-iliac (SI) joint which appeared like an osteoblastic metastasis at first glance. However, absence of uptake in the right renal fossa with the left kidney being normal in position contemplated the probability of right-sidedpelvickidneywhich was confirmed later by a contrast enhanced computerized tomography (CT) scan of abdomen that showed a pelvic right kidney overlying the sacrum.&#x0D; Bangladesh J. Nuclear Med. 22(2): 155-156, Jul 2019

Osteogenic Sarcoma Presenting with Skip, Lymph Nodal, Pulmonary, Pleural Metastases and Malignant Effusion: An Unusual Appearance on Bone Scan.

Osteogenic sarcoma is an aggressive malignant bone tumor arising from primitive mesenchymal bone-forming cells. Ossification is the characteristic feature of the metastases in osteosarcoma which aids their detection on 99mTc-MDP bone scintigraphy. Although lung is the most common site of metastasis in osteogenic sarcoma, pleural involvement with effusion and skip metastases are rare. Herein, we report a case of osteogenic sarcoma of distal femur with diffuse calcified pleural thickening leading to malignant pleural effusion, calcified lung, lymph node, and bone metastases illustrated on bone scan.

Osteoblastic and hyperostotic craniofacial lesion detected by 99mTc-labeled methylene diphosphonate bone scintigraphy and single-photon emission computed tomography/computed tomography: a pictorial essay.

99mTc-bisphophonates bone scan, planar and single-photon emission computed tomography/computed tomography (SPECT/CT) modalities, is a commonly used technique that provides high sensitivity and specificity for detection of osseous metastases. However, besides bone metastases, SPECT/CT provides an accurate evaluation of the localization of the lesions and supplies anatomic information that can be valuable for diagnosis of nonmalignant bone diseases, occasionally disclosed in the skull. Reporting of craniofacial lesions detected by 99mTc-MDP (99mTc-labeled methylene diphosphonate) bone scintigraphy and SPECT/CT in the literature is limited. The aim of this pictorial review is to present the findings detected by 99mTc-MDP bone scintigraphy and SPECT/CT including cases under two broad categories: osteoblastic and hyperostosis craniofacial lesions.

Deep neural network based artificial intelligence assisted diagnosis of bone scintigraphy for cancer bone metastasis

Bone scintigraphy (BS) is one of the most frequently utilized diagnostic techniques in detecting cancer bone metastasis, and it occupies an enormous workload for nuclear medicine physicians. So, we aimed to architecture an automatic image interpreting system to assist physicians for diagnosis. We developed an artificial intelligence (AI) model based on a deep neural network with 12,222 cases of 99mTc-MDP bone scintigraphy and evaluated its diagnostic performance of bone metastasis. This AI model demonstrated considerable diagnostic performance, the areas under the curve (AUC) of receiver operating characteristic (ROC) was 0.988 for breast cancer, 0.955 for prostate cancer, 0.957 for lung cancer, and 0.971 for other cancers. Applying this AI model to a new dataset of 400 BS cases, it represented comparable performance to that of human physicians individually classifying bone metastasis. Further AI-consulted interpretation also improved human diagnostic sensitivity and accuracy. In total, this AI model performed a valuable benefit for nuclear medicine physicians in timely and accurate evaluation of cancer bone metastasis.

The one-in-all diagnostic value of 99mTc-MDP bone scan combining with single-photon emission tomography (SPECT)/CT imaging in spinal osteoblastoma

BackgroundOsteoblastoma (OB) is an intermediate lesion, which makes the accurate preoperative diagnosis very important. 99mTc-methylene diphosphonate (99mTc-MDP) bone scan and SPECT/CT imaging were evaluated for their diagnostic value in spinal OB.MethodsThis study was a retrospective analysis of patients with spinal OB lesions confirmed by pathology and diagnosed with bone scan and SPECT/CT for preoperative diagnosis from January 2008 to December 2018. The uptake levels of OB on planar bone scan were divided into low, medium, and high groups by visual assessment referring to the uptake of the normal rib, spine, and bladder. X-ray, CT, MRI, bone scan, and SPECT/CT imaging of the patients were analyzed for characteristics summary.ResultsTwenty-five patients were diagnosed for spinal OB (17 males and 8 females with a proportion of 2.1:1), and the average age was 26.8 ± 10.8 years (range 5~59). There were 8 lesions located in the cervical, 6 in the thoracic, and 11 in the lumbar vertebrae. Twenty-four lesions involved posterior elements, especially the pedicles (14/25). Symptoms were predominantly painful with a duration of 18.3 ± 13.9 months (range 0.5~60 months). The lesion size ranged from 9 to 35 mm. All the lesions were low to high uptake in the planar bone scan, and the percentages of low to high levels were 1 (4%), 8 (32%), and 16 (64%) cases.ConclusionsSpinal OB mainly involved the posterior area, and elderly patients should be considered as well. SPECT/CT combined the characteristics of bone uptake and anatomical features of bone tumors, proving its one-in-all diagnostic value for spinal OB and other osteogenic tumors.

Radiation exposure awareness from patients undergoing nuclear medicine diagnostic 99mTc-MDP bone scans and 2-deoxy-2-(18F) fluoro-D-glucose PET/computed tomography scans.

Medical imaging is on average the largest source of artificial radiation exposure worldwide. This study seeks to understand patient's awareness of radiation exposure derived from nuclear medicine diagnostic scans and assess if current information provided by leaflets is adequate. Single-centre cross-sectional questionnaire study applied to bone scan and FDG PET/computed tomography patients, at a nuclear medicine and PET/computed tomography department over a 15-week period in 2018. Questionnaires on dose comparators were designed in collaboration with patients, public, and experts in radiation exposure. Qualitative data were analysed using thematic analysis and quantitative data using SPSS (V. 24). A total of 102 questionnaires were completed (bone scan = 50; FDG PET/computed tomography = 52). Across both groups, 33/102 (32.4%) patients reported having a reasonable understanding of nuclear medicine and 21/102 (20.6%) reported a reasonable knowledge of ionising radiations. When asked to compare the exposure dose of respective scans with common comparators 8/50 (16%) of bone scan patients and 11/52 (21.2%) FDG PET/computed tomography answered correctly. On leaflet information, 15/85 (17.6%) patients reported the leaflets do not provide enough information on radiation exposure and of these 10/15 (66.7%) commented the leaflets should incorporate more information on radiation exposure dose. More observational and qualitative studies in collaboration with patients are warranted to evaluate patients' understanding and preferences in communication of radiation exposure from nuclear medicine imaging. This will ensure communication tools and guidelines developed to comply with ionising radiation (medical exposure) regulation 2017 are according to patients needs and preferences.

Radiopharmaceuticals for Treatment of Osteosarcoma.

Although trace amounts of radioactivity are routinely used to detect osteosarcoma, the use of larger therapeutic amounts of radiation is often an unrecognized opportunity to treat metastatic osteosarcoma. This chapter will review a number of approaches to use ionizing radiation in the form of injectable radiopharmaceuticals. Since bone metastases are a common pattern of metastatic spread of cancer in general, a number of bone-seeking radiopharmaceuticals have been developed and FDA approved for treatment of bone metastases. Although osteosarcoma, a bone-forming cancer, would seem ideally suited to be treated with bone seekers, patterns of relapse involving non-ossifying metastases remain a major problem to be overcome. Thus, this review will not only describe experience using a number of bone-seeking radiopharmaceuticals such as 153-samarium-EDTMP, 153-samarium-DOTMP, and 223-radium against osteosarcoma, but also approaches to identify patients who may benefit as well as some means to the improve overall efficacy including combination therapy with routine agents and using nuclear imaging to develop best strategy for use. These include imaging with not only 99mTc-MDP standard bone scans, but also 99mTc-MDP bone scans with SPECT CT, bone-specific sodium fluoride PET-CT (Na18F), and 18FDG-PET-CT. Accurate knowledge of oligometastatic active disease can facilitate more effective use of combination therapy, including radiosensitizers and local control measures, for example, stereotactic body radiotherapy (SBRT) and/or cryoablation to reduce disease burden as well as manage and prevent micrometastatic disease from growing and metastasizing. Finally, a new tumor-specific radiopharmaceutical, CLR 131, may also provide another radiopharmaceutical to treat both osteoblastic and non-ossifying areas of osteosarcoma.

223-Radium for metastatic osteosarcoma: combination therapy with other agents and external beam radiotherapy

BackgroundBone-seeking radiopharmaceuticals can deposit radiation selectively to some osteosarcoma tumours because of the bone-forming nature of this cancer.ObjectivesThis is the first report of using 223-radium, an alpha-emitting calcium analogue with a high therapeutic index, in combination therapy with other agents in 15 patients with metastatic osteoblastic osteosarcoma.MethodsCandidates for alpha-radiotherapy if 99mTc-MDP bone scan had avid bone-forming lesions and no therapy of higher priority (eg, definitive surgery). Monthly 223-radium infusions (1.49 μCi/kg or 55.13 kBq/kg) were given.ResultsThe median infusion number was three and the average time to progression was 4.3 months for this cohort receiving 223-radium+other agents. Agents provided during 223-radium included (1) drugs to reduce skeletal complications: monthly denosumab (n=13) or zolendronate (n=1); (2) agents with antivascular endothelial growth factor activity, pazopanib (n=8) or sorafenib (n=1), (3) alkylating agents: oral cyclophosphamide (n=1) or ifosfamide, given as a 14-day continuous infusion (n=1, two cycles), (4) high-dose methotrexate (n=1), pegylated liposomal doxorubicin (n=1); and (5) two other combinations: nivolumab and everolimus (n=1) and rapamycin and auranofin (n=1). Radiation therapy, including stereotactic body radiotherapy (SBRT), was also given to 11 patients concurrently with 223-radium (n=2), after 223-radium completion (n=3), or both concurrently and then sequentially for other sites (n=6). After 223-radium infusions, patients without RT had a median overall survival of 4.3 months compared with those with SBRT and/or RT, who had a median overall survival of 13.5 months.Conclusion Although only 1/15 of patients with osteoblastic osteosarcoma still remain alive after 223-radium, overall survival

Physiologic Periostitis: Erroneous presentation on 99mTc MDP bone scintigraphy - a case report

Background: Physiologic periostitis (PP) is characterized by periosteal reaction without any inflammatory condition, and with a more common presentation in pediatric age group involving long bones. It can easily be misinterpreted for a pathological process due to asymmetrical presentation in some cases. 99mTc-methylene diphosphonate (MDP) bone scintigraphy is one of the effective tools for its diagnosis as it helps to localize multiple lesions in the whole skeleton. Case Presentation: A male child, 1 month of age, was referred to the nuclear medicine department of our hospital with swelling involving the right hip for 2 weeks with no history of fever and trauma. There was a mild skin discoloration at the site of swelling along with restricted leg movements. The 99mTc-MDP bone scan (BS) showed abnormal increased uptake in the proximal and distal ends of the right femur along with increased uptake in proximal right humerus. X-ray images showed periosteal reaction involving diaphyseal ends of respective long bones, and these findings together with the patient’s history and normal biochemical profile suggested the presence of PP in this case. The patient’s condition was improved later after treatment with non-steroidal antiinflammatory drugs (NSAIDs), thus confirming our diagnosis. Conclusion: PP is one of the differential diagnoses in children presenting with pain or swelling in upper or lower limbs. As the condition is self-limiting, it is important to accurately diagnose this condition before subjecting the child to vigorous testing and treatments. Exceptional behavior of this condition on BS should also be kept in mind.

Avascular necrosis of head of femur mimicking skeletal metastasis on 99mTc MDP bone scintigraphy - a rare case report

Background: 99mTc-Methylene diphosphonate (MDP) bone scan of a patient with known breast carcinoma showed a solitary osteoblastic lesion in the femoral head. Solitary bone metastatic lesion and a benign cause-like remodeling phase of avascular necrosis (AVN) were the top most differential diagnoses and therefore can easily be misinterpreted for each other. Magnetic resonance imaging (MRI) is considered as the gold standard for diagnosis of AVN and can help in differentiation between AVN and skeletal metastasis. Case Presentation: A 40-year-old female patient of right breast carcinoma, treated with mastectomy, chemotherapy, and radiotherapy underwent 99mTc-MDP bone scintigraphy for pain in left hip with restricted movements. The bone scan showed focal uptake in the head of left femur with suspicion of AVN, which turned out to be a metastatic lesion on MRI. Later on, longitudinal follow-up of bone scan after 1 year showed a lesion in the left femoral head extending up to the trochanteric region with additional new lesions confirming skeletal metastasis. Conclusion: Solitary skeletal metastatic lesion in the head of femur is a rare finding, although in the presence of local symptoms AVN always remains at the top of the list for differential diagnosis of solitary osteoblastic focus in the femoral head. Bone scan is a primary tool for skeletal metastatic survey due to high sensitivity but due to low pathognomonic specificity, additional imaging with MRI must be considered as a safe, non-invasive, and easily available option for further characterization of solitary lesions.

Utility of FDG-PET/CT in Patients with Advanced Renal Cell Carcinoma with Osseous Metastases: Comparison with CT and 99mTc-MDP Bone Scan in a Prospective Clinical Trial

Objective: Compare FDG-PET/CT, CT, and bone scan for detecting and monitoring bone metastases’ response in metastatic renal cell cancer (mRCC). Methods: Patients with mRCC prospectively underwent FDG-PET/CT, CT, and bone scans at baseline and after 8 weeks of therapy. Tumor visibility and metabolic activity were retrospectively recorded. Response was evaluated by PERCIST, RECIST, and MD Anderson bone criteria. Kaplan-Meier methodology estimated event-time distributions for PFS, OS, and time to symptomatic skeletal event (SSE). Log-rank test tested differences in event-time distributions between response at 8 weeks by response criteria. Results: Sixteen patients (n = 30; 53%) were evaluable. Baseline FDG-PET/CT detected more osseous metastases (n = 55) than CT (n = 45) or bone scan (n = 34). From baseline to 8 weeks, metabolic activity of lesions decreased &gt;20%, while qualitative and quantitative CT and bone scan parameters were unchanged for most patients. Partial metabolic responders by PERCIST had longer PFS and OS (n = 5, 20+ months) versus those with stable (n = 9; PFS = 9.2 mos, OS = 8.7 mos) and progressive (n = 2; PFS = 5.4 mos, OS = 12.1 mos) metabolic disease, p = 0.09 and 0.42, respectively. By RECIST, longer PFS and OS was seen for stable (n = 12, PFS = 8.3 mos, OS = 17.7 mos) versus progressive (n = 4; PFS = 3.7 mos, OS = 7.5 mos) disease, p = 0.16, 0.02, respectively. OS was not reached, but estimated ≥20 mos, for 4 patients with RECIST SD and PERCIST PMR, compared to OS of 17.7 mos for other patients with RECIST SD. Conclusions: FDG-PET/CT identified more bone metastases and greater numbers of quantitative and qualitative treatment responses in mRCC compared to CT and bone scan. FDG-PET/CT also may identify a sub-group of patients with better outcomes than predicted by standard imaging modalities.

Quantification evaluation of 99mTc-MDP concentration in the lumbar spine with SPECT/CT: compare with bone mineral density.

Despite recent technological advances allowing for quantitative single-photon emission computed tomography (SPECT), quantitative SPECT has not been widely used in the clinical practice of osteoporosis. The aim of this study is to evaluate the feasibility of quantitative bone SPECT/CT for measuring lumbar standard uptake value (SUV) in patients with different bone-mineral density (BMD), and investigate the correlation between SUV measured with 99mTc-methylene diphosphonate (MDP) SPECT/CT and BMD assessment by dual-energy X-ray absorptiometry (DXA). A retrospective analysis of 62 cases 99mTc-MDP whole-body bone imaging and local lumbar SPECT/CT tomography were performed. According to the results of dual-energy X-ray bone density examination, they were divided into normal group, osteopenic group, and osteoporosis group. The raw SPECT data were reconstructed using flash3D which includes attenuation correction, scatter compensation, and collimator resolution recovery, SPECT images from this algorithm were calibrated for SUV analysis. Comparing difference of lumbar SUV in different BMD subjects, and investigating the correlation between lumbar SUV and BMD. Data were analyzed by one-way ANOVA and Pearson regression analysis using SPSS 17.0 software. The maximum SUV (SUVmax) and mean SUV (SUVmean) of L1-L4 vertebral in 62 subjects were 7.39 ± 1.84 and 4.90 ± 1.27, respectively. The average BMD was 0.85 ± 0.15 (g/cm2), and the average CT value was 145.88 ± 53.99 (HU). The SUVmax, SUVmean, BMD, and CT values of the lumbar spine were statistically significantly different among the three groups (F = 24.089, 30.501, 94.847, 30.241, all p < 0.001), and the osteopenic group was significantly lower than the normal group (all p < 0.001), the osteoporosis group was significantly lower than the normal group and the osteopenic group (all p < 0.001). Lumbar SUVmax, SUVmean, and BMD were significantly negatively correlated with age (r = -0.328 to -0.442, all p < 0.05), and positively correlated with body weight and CT value (r = 0.299-0.737, all p < 0.05), but no significant correlation with height (r = 0.006-0.175, all p > 0.05). Lumbar SUVmax and SUVmean increased significantly with the increase of BMD (r = 0.638, 0.632, p < 0.001). The SUV of lumbar spine in 99mTc-MDP bone SPECT/CT was significantly different among subjects with different BMD, and the SUV was positively correlated with BMD. These findings justify that quantitative bone SPECT/CT is an applicable tool for clinical quantification of bone metabolism in osteoporosis patients.

Factors affecting standardized uptake value of 99mTc-MDP bone SPECT/CT: A phantom study

Currently, state-of-the-art SPECT/CT with 3D reconstruction allows for quantitative data that can be represented as standardized uptake value (SUV). However, there are a number of factors that affect the value. The goal of this study was to investigate the factors affecting SUV of 99mTc-MDP bone SPECT/CT. A NEMA phantom with 99mTc-MDP background activity concentration of 18 kBq/ml and tumor to background ratio of 4:1 were studied. The data were acquired based on clinical bone SPECT/CT imaging protocol and OS-EM algorithm with compensation for attenuation, scatter and resolution recovery was applied using 10 subsets and varying iterative numbers from 1 to 5. SUVs (SUVmean and SUVmax) were measured for each sphere using Q.Metrix software. Moreover, three cut-off frequencies of Butterworth filter including 0.35, 0.48 and 0.65 cycle/cm with order of 10 were investigated at 20 iterative updates. The percentage of difference of both SUVs for each sphere was calculated. Both SUVs tended to increase when the iterative update of the OS-EM and cut-off frequency of Butterworth filter were increased. Measurement of SUVs from SPECT/CT is feasible. However, the iterative update, cut-off frequency and sphere size can affect both SUVs.

Meningioma: A false positive finding of metastasis from prostate adenocarcinoma using 68Ga-PSMA PET/CT scan

A 73-year-old man with history of prostatic adenocarcinoma radical prostatectomy underwent 99mTc-MDP whole-body bone scan and subsequent 68Ga-labeled prostate-specific membrane antigen (PSMA) ligand PET/CT for restaging due to a gradual rise of prostate-specific antigen levels. Whole-body bone scan showed two focal zones of slightly increased uptake in the right fronto-parietal and temporal bones. 68Ga-PSMA PET/CT scan showed local recurrence in the prostatic bed and two foci of slightly increased uptake in the right temporal and fronto-parietal lobes. A brain CT scan, with IV contrast confirmed that foci of increased uptake in the temporal and parietal lobes were consistent with typical meningioma.

Measuring the unmeasurable: automated bone scan index as a quantitative endpoint in prostate cancer clinical trials.

Up to 90% of men with metastatic castration-resistant prostate cancer (mCRPC) will have a distribution of disease that includes bone metastases demonstrated on a Technetium-99m (99mTc-MDP) bone scan. The Prostate Cancer Working Group 2 and 3 Consensus Criteria standardized the criteria for assessing progression based on the development of new lesions. These criteriahave been recognized by regulatory authorities for drug approval. The bone scan index (BSI) is a method to quantitatively measure the burden of bony disease, and can assess both disease progression and regression. The automated BSI (aBSI) is a method of computer analysis to assess BSI, and is being qualified as a clinical trials endpoint. Manual searching was used to identify the literature on BSI and aBSI. We summarize the most relevant aspects of the retrospective and prospective studies evaluating aBSI measurements, and provide a critical discussion on the potential advantages and caveats of aBSI. The development of neural artificial networks (EXINI boneBSI) to automatically determine the BSI reduces the turnaround timefor assessing BSI with high reproducibility and accuracy. Several studies showed that the concordance between aBSI and BSI, as well as the interobserver concordance of aBSI, was >0.95. In a phase 3 assessment of aBSI, a doubling value increased the risk of death in 20%, pre-treatment aBSI values independently correlated with overall survival (OS) and time to symptomatic progression. Retrospective studies suggest that a decrease in aBSI after treatment may correlate with higher survival when compared with increasing aBSI. aBSI provides a quantitative measurement that is feasible, reproducible, and in analyses to date correlates with OS and symptomatic progression. These findings support the aBSI to risk-stratify men with mCRPC for clinical trial enrollment. Future studies quantifying aBSI change over time as an intermediate endpoint for evaluating new systemic therapies are needed.

Subacute cerebral infarction incidentally detected by 99mTc-MDP bone scan

Subacute cerebral infarction incidentally detected by 99mTc-MDP bone scan

Indication of 99mTc-MDP bone scan after 123I-MIBG scintigraphy in patients with neuroblastoma

123I-MIBG (metaiodobenzylguanidine) scintigraphy and 99mTc-MDP bone scintigraphy (bone scan) are widely used in diagnosis and staging of NB. Consecutively using both methods lead to overall radiation exposure. As most of the patients need additional anesthesia to perform these diagnostic procedures, which accordingly increase the side effect, workload and expenditure. To minimize the exposure, side effect, workload and expenditure, we set the tasks to optimize the diagnostic algorithm. Determine the indications of bone scan after 123I-MIBG scintigraphy. Materials and Methods: 129 patients with NB were included in retrospective study who underwent both diagnostic procedures at interval of less than 30 days at the stage of initial diagnostic procedure using standard protocols. Out of 83 MIBG positive patients bone scan was able to detect metastatic lesions only in 48 patients. However, bone scan had revealed metastatic lesions in 3 out of 14 MIBG-negative patients. Bone scan is indicated only in MIBG-negative neuroblastoma patients; and in cases where the MIBG uptake cannot be determined for example after operative treatment or after starting of chemotherapy.