Mature cystic teratoma

Vang R, Gown AM, Zhao C, et al. Ovarian mucinous tumors associated with mature cystic teratomas Morphologic and immunohistochemical analysis identifies a subset of potential teratomatous origin that shares features of lower gastrointestinal tract mucinous tumors more commonly encountered as secondary tumors in the ovary. Am J Surg Pathol. 2007 31 854-869. 

Teratomas are the most common ovarian neoplasm in women under 45 years of age, and account for up to 70% of tumors in females less than 19 years of age [67]. Ovarian teratomas derive from germ cells and are classified into three main categories, among vdiich the mature cystic teratomas account for 99%. Less common types of mature teratomas are the monodermal teratomas, which include the struma ovarii and carcinoid tumors. It is typical for monodermal teratomas not to be cystic but contain... 

Dermoid cysts or mature cystic teratomas are composed of mature tissue from at least two of the three... 

At CT and MRI, however, the diagnosis of fat within a cystic mass is pathognomonic for a mature cystic teratoma [73]. The fatty elements display characteristic low CT attenuation (-20 to -120 HU)... 

Carcinoid tumors are frequently associated with a mature cystic teratoma or a mucinous ovarian tumor. Unlike most cystic teratomas, they are predominantly found in postmenopausal women. The course is usually benign rarely will metastases be found. Carcinoid syndrome is uncommon. 

Yamashita Y, Hatanaka Y, Torashima M et al (1994) Mature cystic teratomas of the ovary without fat in the cystic cavity MR features in 12 cases. AJR Am J Roentgenol 163 613-616... 

A minority of dermoid cysts will demonstrate no fat or only small foci of fat within the wall or the Rokitansky nodule (Fig. 9.28) [73]. Yamashita et al. reported that 15% of mature teratomas did not show fat within the cystic cavity. Approximately half of these cases displayed small amounts of fat within the wall of the dermoid or the dermoid plug. In 8% of henign teratomas, no fat could be detected [73]. 

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