Teratoma


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Related to Teratoma: Sacrococcygeal teratoma

teratoma

[‚ter·ə′tō·mə]
(medicine)
A true neoplasm composed of bizarre and chaotically arranged tissues that are foreign embryologically as well as histologically to the area in which the tumor is found.

Teratoma

 

a neoplasm occurring in man and animals that results from the impaired embryonic development of tissues. Found mainly in children and adolescents, it is localized in the sex glands and occasionally in other organs and parts of the body. A teratoma generally consists of different types of tissue, including connective, epithelial, muscular, and neural tissue, and may include such differentiated derivatives of these tissues as teeth and hair.

The most complex teratomas in terms of composition and structure are those that have developed from early blastomeres or from primary sex cells that are totipotential, or able to develop into any type of body tissue. Teratomas that arise at later stages of embryonic development (after gastrulation) are limited in composition by the formative potential of the embryonic germ layer or organ from which the teratomas originate. Simple, relatively benign teratomas are distinguished from teratoblastomas— malignant tumors composed of tissues of embryonic structure and lacking a tendency to differentiate. Simple teratomas are also distinguished from teratoids—developmental defects that are not tumors but that may develop into tumors. Teratomas may become carcinomas or sarcomas.

REFERENCE

Klinicheskaia onkologiia detskogo vozrasta. Edited by M. V. Volkov. Moscow, 1965. (Contains bibliography.)
References in periodicals archive ?
Patients were divided in two groups depending on the presence of a teratoma (on histology of primary tumour or lymphadenectomy residual mass), and we observed correlation in both classifications between the persistence of a residual mass and the presence of teratoma.
2) The common benign primary bone tumors of the pediatric age group include hemangiomas, osteoid osteomas, osteoblastomas, Langerhan cell histiocytosis, aneurysmal bone cysts and sacrococcygeal teratomas.
In evaluating teratoma, alpha fetoprotein (AFP) and/or beta human chorionic gonadotropin ([beta]-HCG) are elevated in 85% of germ cell tumors.
2] There is either selective elimination of the immature components of the teratoma or differentiation of malignant cells into mature teratoma cells.
with a mature teratoma brain tumor to undergo this pioneering laser procedure since the Visualase laser system was approved for non-experimental use in the United States in 2007.
Teratoma was found to be Type II with some intrapelvic extension and was encroaching near the rectal wall which was carefully dissected without any injury.
On imaging, a combination of fluid, fat, calcification and soft-tissue component is highly specific for teratoma (Fig.
Combined cystic teratoma and hepatoblastoma of the liver: probable divergent differentiation of an uncommitted hepatic precursor cell.
A week later, when he visited his aunt again, she was barely conscious, very close to succumbing to spreading of the teratoma.
These VSELs appear to have the ability to signal the body to heal damaged tissue, to grow blood vessels and differentiate into cells of different organs without teratoma or cancer formation.
Josep Dalmau, a neuro-oncologist at Penn, and his colleagues had published studies describing anti-NMDA receptor encephalitis, a rare reaction seen in young women to a common ovarian tumor called a teratoma, which is typically harmless,.
1) reported that teratoma forms 48% of all testicular tumors in prepubertal children which is followed by yolk sac tumor (15%).