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.
GTS is chemotherapeutic retro-conversion characterized by an increase in metastatic mass after complete eradication of a primary malignant ovarian germ cell tumour and by normalization of serum tumour markers, either during or after chemotherapy.1,2 Incidence of GTS is 12% after ovarian germ cell tumours.3,4 There are one hundred one cases of ovarian GTS from literature published between 1977 and 2015.5 Reason for occurrence of GTS is not exactly known but hypothetically there are two major inferences of GTS formation that is chemotherapy transforms malignant cells into "benign" teratomatous
elements and chemotherapy can only destroy malignant cells leaving chemoresistant teratoma behind.4,6
It is associated with teratomatous
components [1-3] and can occur in all ages with mean age of onset ranging between 45 and 50 [1, 3].
In our case, the tumour consisted of well-differentiated mature teratomatous
elements allowing a morphology based diagnosis with no need for immunohistochemical studies.
An appendiceal origin or a teratomatous
component was excluded.
Friedman and Moore were the first to document cases with "neuroepithelioma" and sarcoma arising within teratomatous
germ cell tumours .
The malignant transformation of a teratoma consists of the transformation of a somatic teratomatous
component of a germ cell tumor to a nongerm cell tumor malignant phenotype.
[20.] Hoefnagel D, Benirschke K, Duarte J: Teratomatous
cysts within the vertebral canal: Observations on the occurrence of sex chromatin.
Analysis of 322 cases with special emphasis on teratomatous
lesions and a proposal for histopathologic classification and clinical staging.
The pathologists could find no immature teratomatous
component in multiple sections examined.
Dermoid, epidermoid, and teratomatous
cysts of the tongue and the floor of the mouth.