1,720,978 research outputs found
Can SPET/CT Technique Improve the Sentinel Lymph Node Radio- Guided Research in Cutaneous Malignant Melanoma?
Get PDFBackground: the aim of the study is to define the role of SPET/CT in radio-guided sentinel lymph node surgery identification in cutaneous Malignant Melanoma (MM) and to assess if SPET/CT data can modify surgery time.
Materials and Methods: 96 patients with MM (58 men and 38 women, mean age of 44 years, range 14-71 years) were divided into two groups. 66 patients (group I) were submitted to sentinel node (SN) research by planar
lymphoscintigraphy; 30 patients (group II) performed both planar and SPET/CT lymphoscintigraphy. SN surgery identification percentage, SN anatomical site identification and surgery times were evaluated in each group.
Results: Group II presented a percentage of SN surgery identification, both globally (96.5%) and in specific sites (axilla lymph nodes 94.5%; upon clavicle lymph nodes 100%), better than group I. Furthermore surgery time was shorter in the group II (10’-20’).
Conclusions: SPET/CT allows a more accurate SN identification than planar lymphoscintigraphy, especially in axillar and upon-clavicular nodes and contributes to a correct staging of cutaneous MM. It can improve surgery success percentage and shortens surgery time, reducing also surgery team irradiation
Synergism Between Immunotherapy and Radiotherapy in Esophageal Cancer: An Overview of Current Knowledge and Future Perspectives
Get PDFBackground:
Esophageal cancer (EC) is an aggressive neoplasm of the gastrointestinal tract that is usually treated with a combination of chemotherapy, radiotherapy (RT), and/or surgery, according to disease status. Despite the availability of multimodal therapeutic strategies, local recurrence is frequently observed. Immunotherapy is a promising therapeutic approach that is currently highly investigated in association to standard therapies, including RT, with the aim to improve patients' outcomes.
Materials and Methods:
A PubMed search was performed with the following keywords in all fields: "esophageal cancer" and "radiotherapy" and "radiation" and "immunotherapy" and "PD-1" and "PD L1." For an overview of ongoing trials, an additional search on ClinicalTrials.gov website was performed using the keywords "esophageal cancer" and "immunotherapy" and "PD-L1" and "CTLA-4" and "radiation" and "radiotherapy." Emerging data from preclinical and clinical studies are suggesting a synergistic effect between immunotherapy and RT. With the aim to update the knowledge of this synergistic immune-mediated antitumor activity and discuss current challenges, the authors summarize published data concerning the basic mechanisms and the effectiveness and tolerance of the combination between immunotherapy and RT for patients with EC, followed by an overview of ongoing clinical trial.
Conclusions:
Published results encourage the use of personalized therapeutic approaches for EC patients in the future; results from ongoing studies will help to identify the optimal strategies for patient selection and treatment response evaluation
Increased and normalized uptake of 18F-FDG in a case of bone periprosthetic infection treated by antibiotics
No full textWe report the case of a 69 years old man with left hip prosthesis, who presented clinical, biochemical and imaging signs of periprosthetic infection treated with linezolid, an antibacterial agent of the oxazolidinone class. Two weeks after this treatment, a fluorine-18-fluoro-2-deoxy-d-glucose positron emission to-mography/computed tomography (18F-FDG PET/CT) scan showed increased uptake in the skeleton and also increased uptake in several focal areas in the spine and near the prosthesis and the surgical wound on the left gluteus medius. Bone marrow biopsy was negative; meanwhile the antibiotic therapy, after four weeks of treatment was stopped due to red blood cells and platelets toxicity. Six weeks later, the patient developed high fever again and in order to revaluate the periprosthetic inflammation, he was resubmitted to 18F-FDG PET/CT which showed normal 18F-FDG uptake in the whole skeleton, including the prosthesis and the subcutaneous wound. Some focal areas of increased uptake in the lumbar spine were still detected. In the next 4 weeks the patient was under a "watch and wait" follow-up in a steady state. In conclusion: In the case we report, since we found no other reason, we consider that the increased uptake of the 18FFDG in the skeleton was due to an increased metabolic reaction of bone marrow to infection normalized after treatment. The myelosuppressive action of linezolid could be another factor. The persistent focal areas in the lumbar spine where due to age-related bone deformities including some Schmorl's nodes. The inflammation in the bone prosthesis and the subcutaneous wound responded almost totally to the antibiotic treatment we applied
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Sickle cell diseases: What can nuclear medicine offer?
No full textSickle cell disease (SCD) is the best known haemoglobinopathy, caused by a mutation substituting valina for glutamic acid at position 6 of the beta-globin chain of adult hemoglobin A, resulting in hemoglobin S (HbS). The homozygous HbS disease (HbSS), an autosomal recessive disorder, is the most common form and the Mediterranean area, along with sub-Saharian African and India, have the highest prevalence (1%-15%). In particular, Sicily with a prevalence of 2%-5%, is among the most interested regions. However, migratory flows have led to a wider diffusion of the disease no longer confined to endemic areas. In Europe, the yearly estimate of affected births are 1,300 but more than 90% of children with SCD survive into adulthood thanks to screening programs and early available care; however, their lifespan remains shortened by two or three decades compared to general population. In Greece, the number of affected births surpassing 100,000 yearly and the total number of newborns carrying two deleterious genes, if no prevention measures are taken, is estimated to be about 120-130/year. Diagnosis of SCD is based on analysis of haemoglobin through protein electrophoresis or chromatography, that are cheap and widely available techniques, even if haemoglobin mass spectrometry and DNA analysis are techniques with high-throughput testing. Prenatal diagnosis is used in many European countries, so the number of affected newborns has significantly decreased during the last 3 years. Over the course of SCD, sickling process may cause acute and chronic abdominal pain due to vaso-occlusive crisis, bone pain often in long bones due to bone marrow infarction, chronic hemolytic anemia, splenic sequestration with rapid enlargement of the spleen, delayed sexual maturation and cholelithiasis, with important inter-indivuidual variability. Sickle hepatopathy reflects liver sickling process within hepatic sinusoids and includes gallstone disease, hepatic sequestration, hepatic sideroris, acute sickle cell hepatic crises (ASHC) and sickle cell intrahepatic cholestasis (SCIC). Clinically, it appears with fever, right upper quadrant pain, jaundice and increased serum liver function tests. These patients are repeatedly esposed to trasfused red cells that contributes to iron overload and may contribute to hepatic haemosiderosis. Increased bone turnover and resorption by osteoclasts and by marrow expansion due to activation of hematopoiesis. The hematopoietic system may expand physiologically. Computed tomography (CT) is an easily reproducible imaging method that allows the morphologic whole-body evaluation although with a high dose of radiation exposure and possible side effects from intravenous contrast media. Magnetic resonance cholangiopancreatography (MRCP) is a noninvasive technique without radiation chosen to image cholangiopathy and may be followed by the execution of endoscopic retrograde cholangiopancreatography (ERCP) in case of gallstone disease. Otherwise it can be helpful in identifying extramedullary hematopoiesis sites. Dual-energy X-rays absorptiometry (DEXA) is performed to evaluate deficit of bone mineral density (BMD), in which reduction of osteoblastic activity, high risk for necrosis may induce to fragility fractures. We recently had the experience of a typical case of a 56 years old Albanian woman with SCD, with jaundice after a long history of recurrent vaso-occlusive crisis. She was submitted to splenectomy and cholecystectomy 5 years before and since then she was treated with hydroxyurea. Hemocromatosis was excluded by genetic analysis. Hepatic biopsy (Pearl's stain) showed sinusoidal dilatation and diffuse iron accumulation in hepatocytes and Kupffer cells. Endo-hepatic jaundice was observed in MRCP images. It was interesting that DEXA examination was within normal range in both right proximal femur. This may probably be due to the presence of sclerotic lesions in the vertebrae, as was seen in the CT images. Technetium-99m-methylen bisphosphonate (99mTc-MDP) skeletal scintigraphy is a higly sensitive whole-body diagnostic nuclear medicine technique able to evaluate early bone metabolic changes. Multimodality SPET/CT allows to correlate scintigraphic findings with anatomical images with higher sensitivity and specificity. The higher uptake of 99mTc-MDP in SCD patients is due to the activation of hematopoetic system and relies on the osteoblastic response to bone resorption as in our patient. The 99mTc-MDP scan may be better than fluorine-18-fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG PET/CT) to show sclerotic lesions. Technetium-99m nanocolloids bone marrow scintigraphy (BMS) provides information about the assessment of the reticulum-endothelial system (RES), the whole-body distribution of functional red bone marrow and the presence and the extent of extramedullary hematopoiesis, especially in liver, spleen and bone marrow. Fluorine-18-FDG PET/CT completes the whole-body assessment with an integrated multimodal approach with high spatial resolution that evaluates the metabolic activity and the standardized uptake value (SUV) in SCD patients. Modern genetic diagnosis and gene treatment give promise for having fewer cases of SCD in the future
How often suspected pulmonary embolism is diagnosed and its main diagnostic characteristics, in an emergency nuclear medicine service? Four years experience
Get PDFAcute pulmonary embolism (APE) is an emergency condition and its treatment must be immediate. Nevertheless, the diagnosis of APE is diffcult because its symptoms and risk factors are not specific. We present our 4 years experience on this subject
Typical and atypical PET/CT findings in non-cancerous conditions
No full textNuclear Medicine multimodality imaging, such as positron emission tomography/computed tomography PET/CT, refers to metabolic tissue characteristics integrated with anatomical details. Fluorine-18-fluorodeoxyglucose (18F-FDG) is the most diffuse radiopharmaceutical and its application is spreading beyond the area of oncology. The causes of high 18F-FDG uptake that were once considered false positives have been identified and the new knowledge about them led to non-cancerous pathologies that can be studied by 18F-FDG PET/CT. This technique, due to the inflammatory cells high avidity of 18F-FDG, can be useful in studying a variety of inflammatory and infectious systemic conditions. Studies performed in patients with fever of unknown origin (FUO) indicate that 18F-FDG PET/CT offer a great advantage of detecting malignancy, inflammation and infection at the same time both in adults and children. Furthermore, the 18F-FDG PET/CT has proved useful in the study of specific organs such as the heart and brain that represent separate topics also for the development of new specific radiopharmaceuticals. In all the non-oncologic conditions 18F-FDG PET/CT imaging may offer an "all-in-one" procedure, thanks also to its panoramic whole-body acquisition, as an alternative to other diagnostic procedures, reducing the number of unnecessary investigations. The 18F-FDG PET/CT finding of the simultaneous presence of radiopharmaceutical uptake for multiple disease interconnect to different medical disciplines. It is important to describe unexpected occasional typical or atypical PET/CT findings to the growth of scientific and medical community; it can be the starting point to the enlargement of PET/CT indications for a better and wider comprehension of the human system. To recognize unexpected occasional findings is very important a well knowledge of many aspects: physiological biodistribution, diagnostic imaging instrumentations and techniques, pathological aspects of the different neoplastic diseases, patient story, such as previous therapy, and its comorbidity. An unexpected occasional finding can lead to suggest further tests or investigations in order to have a wider comprehension of patients' clinical situation and they are easily explainable when we have a physician's approach towards patient
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