teratoma
Look up teratoma in Wiktionary, the free dictionary. [1]
For a diagnosis of primary thyroid teratoma one of three conditions must be met: a tumor must occupy a portion of the thyroid gland, a direct connection must exist between the tumor and the thyroid, or a teratoma is accompanied by the absence of the thyroid. [2]
A teratoma (pleural: teratomata) is a germ cell tumor derived from pluripotential cells and made up of elements of different types of tissue from one or more of the three germ cell layers. [3]
Some authors use the term dermoid cyst as a frank synonym for teratoma, meaning any teratoma, regardless of its histology or location. [4]
Definitive diagnosis of a teratoma is based on its histology: a teratoma is a tumor with tissue or organ components resembling normal derivatives of all three germ layers. [1]
A tumor consisting of different types of tissue, as of skin, hair, and muscle, caused by the development of independent germ cells. [5]
When a rhabdomyoblastic component is seen, a variety of heterologous or mixed tumors must be ruled out, and when multiple components appear malignant, terms such as malignant mesenchymoma and malignant ectomesenchymoma may be applied. [3]
The rare malignant dermoid cyst usually develops squamous cell carcinoma in adults; in babies and children it usually develops endodermal sinus tumor. [4]
Teratomas of embryonal origin are congenital; teratomas of germ cell origin may or may not be congenital (this is not known). [1]
A teratoma is generally regarded as a congenital (developing prior to birth) tumor formed by tissue represented by the three layers: ectoderm, entoderm and mesoderm. [6]
The majority of teratomas occur in the testes or ovaries (gonads) or the lower back (sacrococcygeal region). [2]
Teratomas range from benign, well-differentiated (mature) cystic lesions to those that are solid and malignant (immature). [7]
Teratomas can be malignant, depending on the maturity and other types of cells that may be involved. [...] Because these sacrococcygeal tumors are often visible from the outside of the body, diagnosis is made early and treatment and/or surgery are initiated early, making the prognosis for this type of germ cell tumor very favorable. [6]
Malignant teratoma is a type of cancer that involves cysts that contain one or more of the three main types of cells found in a developing baby (embryo). [8]
Sources:
[1] Teratoma - Wikipedia, the free encyclopedia (en.wikipedia.org/wiki/Teratoma)
[2] CIGNA - Cervical Teratoma (www.cigna.com/healthinfo/
[3] Teratoma (www.maxillofacialcenter.com/
[4] Dermoid cyst - Wikipedia, the free encyclopedia (en.wikipedia.org/wiki/Dermoid_cyst)
[5] teratoma: Definition from Answers.com (www.answers.com/topic/teratoma)
[6] Teratoma - My Child Has - Children’s Hospital Boston (www.childrenshospital.org/az/
[7] eMedicine - Teratoma, Cystic : Article by Chad A Hamilton (www.emedicine.com/med/topic2248.htm)
[8] MedlinePlus Medical Encyclopedia: Malignant teratoma (www.nlm.nih.gov/medlineplus/ency/