Gestational and nongestational trophoblastic tumors distinguished by DNA analysis

Abstract

In three patients in whom a diagnosis of gestational trophoblastic tumor was possible on the basis of pathology and elevated levels of serum human chorionic gonadotrophin, locus‐specific minisatellite probes were used to identify restriction fragment length polymorphisms (RFLP) in DNA from the tumor, the patient, and her partner. On the basis of results from these studies, one tumor, originally diagnosed as a germ cell tumor, was reclassified as a gestational choriocarcinoma, whereas a second tumor, diagnosed as gestational choriocarcinoma, was shown to be of nongestational origin. In the third case, a diagnosis of gestational trophoblastic tumor was confirmed, but in this case the androgenetic origin of the tumor indicated that it was derived, not from the antecedent term pregnancy, but from a previous pregnancy with hydatidiform mole. This study clearly demonstrates the value of DNA analysis in the classification of tumors with trophoblastic differentiation.

Three histologically distinct cancers of the uterine corpus: A case report and review of the literature

“…Choriocarcinomas of gestational and non-gestational origin have a distinct prognosis, but cannot be distinguished by routine histological examination (22). Molecular genetic analysis may reliably identify the genetic origin of a pure ovarian choriocarcinoma (23)(24)(25); however, as this is an unestablished and costly technique with limited availability, it was not used it in this case. However, our patient was in the high-risk group of endometrial cancer due to the lymph node metastasis and the histological type, i.e., undifferentiated carcinoma (26).…”

Nongestational primary choriocarcinoma of the ovary: A case report

“…Presence of other germ cell elements is indicative of germ cell choriocarcinoma. Choriocarcinoma of gestational origin can be established by identification of paternal component with the help of DNA analysis which is a reliable method for identifying the genetic origin of pure ovarian choriocarcinomas 10,13,14,15 . However, since such techniques are always expensive and not generally available in our institution,, the application is limited.…”

Genetic evidence that placental site trophoblastic tumours can originate from a hydatidiform mole or a normal conceptus

“…1981: Chaganti et al. 1990Fisher et al, 1992) or from a pregnancy with complete hydatidiform mole which is androgenetic, having only a paternal contribution to the nuclear genome (Fisher et al, 1988;Fisher et al. 1992).…”

“…Genetic studies have confirmed the origin of choriocarcinoma from normal term pregnancy or homozygous or heterozygous complete hydatidiform moles (Fisher et al, 1988;Chaganti et al, 1990;Fisher et al, 1992), but have also shown that the causative pregnancy in trophoblastic tumours is not always the antecedent pregnancy (Fisher et al, 1992). Thus a clinical diagnosis of post-term or post-mole PSTT is not conclusive evidence of the origin of the tumour.…”