الفهرس 
General Highlights on Pediatric OncologyOnly 14 pages are availabe for public view
 |  | from | 157 |  |  |
| | | from | 157 | | |
Abstract
Children with cancer deserve the very best and most compassionate care that society can provide. Those charged with creating public policy in the content of diagnostic medicine must make common cause with physicians and other scientists to ensure that the best possible care is realized at the bedside. It has been said that developments in molecular biology and genomics will cause medicine to change more in the next few decades than it has over the past several centuries. moreover, PET will have an important role to play at the ”bedside” in realizing the benefits of our growing understanding of the molecular basis of disease and its treatment.
PET is emerging as an important diagnostic imaging tool in the evaluation of pediatric cancers together with the recent event of dual-modality. It is important to consider potential causes of misinterpretation of FDG-PET that relate to physiologic variations in FDG distribution in children. These include a more extensive distribution of hematopoietic marrow than in adults and the occurrence of high FDG uptake in the thymus, in the adenoids and tonsils, and in the skeletal growth centers. particularly those of the long bone physes. Other potential pitfalls. similar to those in adults, include variable FDG uptake in working skeletal muscles, brown fat, myocardium, thyroid gland, and gastrointestinal tract, as well as accumulation of excreted FDG in the renal pelvis, ureter, and bladder, and possible tracer accumulation in draining lymph nodes from extravagated tracer at the time of intravenous tracer administration. Diffuse increased bone marrow and splenic FDG uptake after the administration of hematopoietic stimulating factors also may resemble disseminated metastatic disease.
PET/CT imaging systems that has added unprecedented diagnostic capability by revealing the precise anatomical localization of metabolic information and metabolic characterization of normal and abnormal structures in a single study. The use of CT transmission scanning for attenuation correction has shortened the total acquisition time, which is an especially desirable attribute in pediatric imaging.
It was shown that most tumors in children are metabolically active and thus concentrate and retain FDG, FDG-PET and FDG-PET/CT provide useful diagnostic and staging information in individual tumor types they play a total role in the clinical management and care of children with cancer as it adds a new dimension to response and risk assessment in pediatric tumors. There is potential not only to improve the outcomes of suboptimally responding patients through earlier intervention but also to spare low risk patients from aggressive treatments. treatment plan to the individual patient is based on the PET/CT result should be feasible.
Positive findings on 18F-FDG PET could be accurately localized on the corresponding CT studies, and equivocal findings on CT could be verified or disproved by their FDG uptake. Therefore, the number of additional imaging studies for further evaluation of equivocal findings on either PET or CT could be significantly reduced.
PET/CT exhibits significantly higher sensitivity, specificity, and accuracy than conventional imaging (CT). It has led to important changes in the clinical management of lymphoma (32%),brain tumors (15%) and sarcomas (13%).
Radiation exposure should be fully considered in examinations of pediatric patients. The injection dose of 18F-FDG and the tube current of the CT portion of PET/CT are adjusted according to the patient’s weight. Thus, the total radiation dose per examination was lower in pediatric population than that in adult patients, while the image quality of the PET or CT portion in each examination was kept sufficient. However, reduction of radiation dose per examination may be necessary, if applicable in pediatric patients requiring repeated imaging evaluation, such as patients’ with lymphoma.