- A childhood tumor that arises in the adrenal gland or in tissue in the nervous system that is related to the adrenal gland. Neuroblastoma affects newborn babies and children up through the age of 10. In the adrenal it develops in the medulla (the central part) of the gland. In the nervous system it arises in one of the ganglia of the autonomic nervous system; a neuroblastoma so arising is sometimes termed a sympathicoblastoma. Neuroblastoma is the most common solid tumor outside the brain in infants and children. There are about 600 new cases diagnosed each year in the US. This tumor can regress (go away) on its own. Unfortunately, most children over a age of year have metastatic disease, disease that has already spread — the spread is most commonly to the lymph nodes, liver, lungs, bones, and bone marrow — by the time of diagnosis, so there is often a very poor outcome despite aggressive therapy. Neuroblastoma is predominantly a tumor of early childhood; two thirds of children with neuroblastoma are diagnosed when they are younger than 5 years of age. It is often present at birth but usually is not detected until later; in rare cases, neuroblastoma can be detected before birth by fetal ultrasound. The most common symptoms of neuroblastoma are the result of pressure by the tumor or bone pain from cancer that has spread to the bone. Protruding eyes and dark circles around the eyes are common and are caused by cancer that has spread to the area behind the eye. Neuroblastomas may compress the spinal cord, causing paralysis. Fever, anemia, and high blood pressure are found occasionally. Rarely, children may have severe watery diarrhea, uncoordinated or jerky muscle movements, or uncontrollable eye movement. Approximately 70% of all patients with neuroblastoma have metastatic disease at diagnosis. The prognosis for patients with neuroblastoma is related to their age at diagnosis (the younger, the better the prognosis), clinical stage of their disease, and (in patients older than 1 year of age) whether they do or do not have regional lymph node involvement by the tumor.
* * *A malignant neoplasm characterized by immature, only slightly differentiated nerve cells of embryonic type, i.e., neuroblasts; typical cells are relatively small (10–15 μm in diameter) with disproportionately large, darkly staining, vesicular nuclei and scant, palely acidophilic cytoplasm; they may be arranged in sheets, irregular clumps, or cordlike groups, as well as occurring individually and in pseudorosettes (with nuclei arranged peripherally about the centrally directed cytoplasmic processes); ordinarily, the stroma is sparse, and foci of necrosis and hemorrhage are not unusual. Neuroblastomas occur frequently in infants and children in the mediastinal and retroperitoneal regions (approximately 30% associated with the adrenal glands); widespread metastases to the liver, lungs, lymph node s, cranial cavity, and skeleton are very common.- olfactory n. a rare, often slowly growing malignant tumor of primitive nerve cells, usually arising in the olfactory area of the nasal cavity. SYN: olfactory esthesioneuroblastoma.
* * *neu·ro·blas·to·ma .n(y)u̇r-ō-blas-'tō-mə n, pl -mas also -ma·ta -mət-ə a malignant tumor formed of embryonic ganglion cellsneu·ro·blas·to·mal -'tō-məl adj
* * *n.a malignant tumour, usually of childhood, composed of embryonic nerve cells. It may originate in any part of the sympathetic nervous system, most commonly in the medulla of the adrenal gland, and secondary growths are often widespread in other organs and in bones. It can nevertheless respond profoundly to systemic chemotherapy.
* * *neu·ro·blas·to·ma (noor″o-blas-toґmə) sarcoma consisting of malignant neuroblasts, usually arising in the autonomic nervous system (sympathicoblastoma) or in the adrenal medulla; it is considered a type of neuroepithelial tumor and affects mostly infants and children up to 10 years of age.
Medical dictionary. 2011.