The tumor originates in the small blood vessels of the oral mucosa, eyes, lips, cheeks, tongues, and subcutaneous tissue of the extremities (78% of all cases). About 18% of cases involve major veins i.e. 5 cases involved the common femoral veins and one case each involved the femoral vein, common iliac vein, inferior vena cava, and subclavian vein. Cases involving the ascending aorta have also been reported. The presenting symptoms of these tumors were strictly dependent on their locations and impacts on the involved vasculature. Most cases involving superficial sites presented with a small (mean diameter of 1.5 cm), painless, slowly growing mass. However, tumors growing in deep tissues went unnoticed until they became large (e.g. 15 cm.) enough to obstruct blood flow: two cases involving the ascending aorta presented with the signs and symptoms of acute aortic dissection (e.g. severe pain, congestive heart failure, cardiac arrest, fainting , stroke, ischemic peripheral neuropathy, and/or paraplegia) while 9 cases involving large veins presented with acute swelling, pain, and tissue/organ dysfunctions in the areas drained by the involved veins. Pathology
The microscopic histopathology of hematoxylin and eosin stained nodular fasciitis tumors (see above and three below figures) consists of spindle-shaped myofibroblastic cells (i.e. cells with features of smooth muscle cells and fibroblasts.). These cells are in a myxoid (i.e. more blue or purple compared to normal connective tissue because of excessive uptake of the hematoxylin stain) or a collagenous (high content of collagen fibers) tissue background. The neoplastic myofibroblasts are arranged in whorls and/or short bundles.
It is divided into the midbrain, pons, and medulla oblongata. Spinal cord
The spinal cord is considered a part of the central nervous system. It is made up of the same cells as the brain: neurons and glial cells. Diagnosis
Although there is no specific or singular symptom or sign, the presence of a combination of symptoms and the lack of corresponding indications of other causes can be an indicator for investigation towards the possibility of a brain tumor. Brain tumors have similar characteristics and obstacles when it comes to diagnosis and therapy with tumors located elsewhere in the body. However, they create specific issues that follow closely to the properties of the organ they are in.The diagnosis will often start by taking a medical history noting medical antecedents, and current symptoms. Clinical and laboratory investigations will serve to exclude infections as the cause of the symptoms. Examinations in this stage may include the eyes, otolaryngological (or ENT) and electrophysiological exams. The use of electroencephalography (EEG) often plays a role in the diagnosis of brain tumors.Brain tumors, when compared to tumors in other areas of the body, pose a challenge for diagnosis. Commonly, radioactive tracers are uptaken in large volumes in tumors due to the high activity of tumor cells, allowing for radioactive imaging of the tumor. However, most of the brain is separated from the blood by the blood-brain barrier (BBB), a membrane that exerts a strict control over what substances are allowed to pass into the brain.