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PET/CT devices with an axial field-of-view (FOV) of 1 m allow simultaneous imaging from the head to the upper thighs, the typical axial extent of many "whole-body" oncological studies acquired by moving a patient sequentially through a conventional FOV device, or rapid total-body imaging using the same approach. Increasing the FOV to around 2 m provides true simultaneous total-body imaging. Either approach dramatically increases the sensitivity for detection of annihilation events arising within the body. For the purposes of this review, both configurations are considered to represent "total-body" PET/CT devices because they share both advantages and disadvantages. These pros and cons are discussed in the context of both clinical and research applications from a patient and institutional perspective., Competing Interests: Declaration of competing interest RJH is the founder and major shareholder of PreMIT Pty Ltd and Precision Molecular Imaging and Theranostics Pty Ltd, which are involved in developing novel theranostic agents and have a collaborative research agreement with Siemens Healthineers. He is also an advisor to GE Medical Systems and a shareholder and Scientific Advisor to Telix Pharmaceuticals. REW is a director and shareholder in Cyclotek Australia Pty Ltd, which is a commercial supplier of PET radiopharmaceuticals in Australia. He is also a shareholder in PreMIT Pty Ltd and Precision Molecular Imaging and Theranostics Pty Ltd. JC has no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)

Although bone-scanning agents remain important for the detection of bone metastasis, the most common site of distant disease in prostate cancer, novel molecular imaging techniques are entering into clinical practice that provide new opportunities to both detect and characterize sites of involvement by prostate cancer, particularly in the setting of recurrent or advanced metastatic disease based on biochemical, clinical or imaging criteria. These approaches can define disease burden, guide locoregional salvage therapies, and select and monitor systemic treatment. While a wide array of tracers is available, the clinical role of broad classes of agents will be reviewed. An exciting and emerging role of molecular imaging is its use in selecting patients for radionuclide therapy., (Copyright © 2019 Elsevier Inc. All rights reserved.)

The vast majority of the world's population of children and adults with sickle cell disease (SCD) are born in low-resource settings, particularly in sub-Saharan Africa, the Caribbean, the Middle East, and India. As a result numerous well-established, cost-effective, and evidence-based strategies for managing SCD such as newborn screening, early education, vaccinations, screening for stroke prevention, and treatments with safe transfusions and hydroxyurea are often unavailable, leading to substantial morbidity and increased mortality. Collaborations between high-income countries and these low-resource settings (North-South partnerships) have been advocated, with the goal of improving clinical care. Based on directives promulgated by the World Health Organization, we have developed a strategy of developing prospective research programs that focus on training, capacity building, and local data collection. This strategy involves consideration of important guiding principles, full partnerships, proper planning, and financial issues before program launch, after which rigorous program management is required for full effect and long-term sustainability. Ultimately these collaborative research programs should help create national guidelines and lead to improved clinical care for all children and adults with SCD., (Copyright © 2018 Elsevier Inc. All rights reserved.)

Hydroxyurea therapy offers promise for ameliorating the clinical course of children with sickle cell disease (SCD). Hydroxyurea is a prototypic therapeutic option; it can be administered with minimal side effects, has a relatively wide therapeutic window, and has mechanisms of action that address pathophysiologic pathways of sickling, vaso-occlusion, hemolysis, and organ damage. There are limited data regarding hydroxyurea's ability to prevent or diminish organ dysfunction, and the long-term risks of hydroxyurea therapy remain incompletely defined. Although clinical trials are underway to address long-term issues, hydroxyurea remains an effective but underutilized therapy for SCD.

Immunoglobulin that recognizes and binds specifically to the erythrocyte D antigen (anti-D globulin, WinRho SDF; Nabi, Boca Raton, FL) has recently been shown to be an effective therapy for many patients with idiopathic thrombocytopenic purpura (ITP). Its mechanisms of action are not completely understood. Intravenous (IV) infusion of anti-D into a D-positive recipient leads to antibody coating of circulating erythrocytes that are cleared primarily by the spleen. This immune-mediated clearance of sensitized erythrocytes occupies the reticuloendothelial system and allows survival of antibody-coated platelets. Based on clinical observations, experimental data, and theoretical calculations, the efficacy of anti-D therapy in ITP depends on several factors that influence the amount of erythrocyte sensitization and the rate of immune-mediated erythrocyte clearance by the spleen. Antibody characteristics, including the antibody concentration, binding affinity, and dissociation constants, may be important, as well as the number of D-antigen binding sites on the erythrocytes. Although the primary mechanism of action of anti-D is believed to be immunologic blockade of Fc receptors (FcR) within the reticuloendothelial system (RES), other immunomodulatory effects are also possible.

Sickle hemoglobinopathies include sickle cell disease, sickle-C disease, and sickle-beta thalassemia. Patients with these disorders commonly suffer a multitude of destructive events to vital organs, especially to the central nervous system, the spleen, the kidney, the lung, and the heart as a result of microvascular plugging by the sickled erythrocytes. Thoughtful preparation for anesthesia and operation, especially when directed by experienced individuals, can greatly reduce the hazard of inducing the sickle crises that formerly plagued individuals with sickle hemoglobinopathies who faced major operations under general anesthesia. The patient must be free of any acute illness, especially one involving the respiratory system. Adequate hydration preoperatively combined with avoiding perioperative hypoxia, hypothermia, and acidosis, the triggers for sickling, will go far toward avoiding sickle-induced complications. Modern transfusion therapy, consisting of multiple small transfusions of Hb A erythrocytes administered over several weeks prior to the operation, not only corrects the chronic anemia but suppresses erythropoiesis of cells containing Hb S in the patient's bone marrow and leaves him or her with a majority of cells containing Hb A. This provides a safety net in case a sickle-inducing insult occurs despite the best efforts to avoid one. Individuals with sickle hemoglobinopathies may require any of the operations common to all children, for example, herniorrhaphy, appendectomy, tonsillectomy, and circumcision, but a significant number will develop calcium bilirubinate cholelithiasis and possibly cholecystitis as a result of the continual increased load of bile salts resulting from the shortened lifespan of the cells containing Hb S. Also, although most individuals with Hb S will gradually suffer splenic infarction by late childhood, a significant number of infants will experience acute splenic sequestration crisis, a life-threatening entity, the recurrence of which is prevented by splenectomy. Several publications have demonstrated that such surgical procedures can be performed in large numbers of patients with sickle hemoglobinopathies without deaths and with minimal morbidity.