In either case, "fusion-negative" alveolar rhabdomyosarcoma have similar clinical presentation and outcome as embryonal rhabdomyosarcoma, thus risk stratification, prognosis, and treatment intensity of rhabdomyosarcoma are now determined by fusion-status instead of histological classification. Imaging
After a physical exam, formal diagnosis of RMS in adult patients requires a computed tomography (CT) scan, which can assess the areas affected and to delineate the tumor. In children, physicians may opt for magnetic resonance imaging (MRI) to limit radiation exposure in younger populations. In the majority of individuals diagnosed with rhabdomyosarcoma, more than half are diagnosed before the age of 10. Prognosis
The prognosis for rhabdomyosarcoma has improved greatly in recent decades, with over 70% of people surviving for five years after diagnosis. The combined use of radiotherapy and surgery has significantly reduced the mortality rates compared to patients who did not undergo any radiotherpay or chemotherapy treatments. Embryonal rhabdomyosarcoma is generally associated with better prognosis than alveolar rhabdomyosarcoma, with a 5-year survival prognosis of 82% and 53%, respectively. This may be due to the more aggressive and metastatic nature of ARMS that can be attributed to its PAX3–FOXO1 or PAX7–FOXO1 gene fusions. Nevertheless, some embryonal rhabdomyosarcoma patients with a rare Leu122Arg mutation in MYOD1 gene have a very poor outcome. In two different studies, none of the subjects with the MYOD1 mutation survived. Tumors due to this mutation commonly manifest in the head and neck area, causing the mutated protein to behave like an oncogene.There have not been many studies linking the genetic profile and clinical outcome of ERMS.
Pre-excitation syndrome is a heart condition in which part of the cardiac ventricles are activated too early. Pre-excitation is caused by an abnormal electrical connection or accessory pathway between or within the cardiac chambers. Pre-excitation may not cause any symptoms but may lead to palpitations caused by abnormal heart rhythms. It is usually diagnosed using an electrocardiogram, but may only be found during an electrophysiological study. The condition may not require any treatment at all, but symptoms can be controlled using medication or catheter ablation. Types
Several types of pre-excitation syndrome have been described. Pathophysiology
Normally, the atria and the ventricles are electrically isolated, and electrical contact between them exists only at the "atrioventricular node". In all pre-excitation syndromes, at least one more conductive pathway is present. Physiologically, the normal electrical depolarization wave is delayed at the atrioventricular node to allow the atria to contract before the ventricles. However, there is no such delay in the abnormal pathway, so the electrical stimulus passes to the ventricle by this tract faster than via normal atrioventricular/bundle of His system, and the ventricles are depolarized (excited) before (pre-) normal conduction system. References


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