Increased gestational age at evacuation of a complete hydatidiform mole: does it correlate with increased risk of requiring chemotherapy?

OBJECTIVE: To assess whether a complete hydatidiform mole (CHM) carries an increased risk of later requiring chemotherapy in pregnancies continued to term. STUDY DESIGN: The Charing Cross gestational trophoblastic neoplasia (GTN) database was screened between 1973 and 2002 to identify registered singleton CHMs with a known gestational age at the time of evacuation. Of the 8,313 cases 2,800 were centrally histopathologically reviewed by us and confirmed as CHM. The proportion of patients requiring chemotherapyfor both total registered and centrally reviewed patients was analyzed by trimester of evacuation (< 13, 13-24, > 24 weeks). Statistical significance was assessed by the chi2 test. RESULTS: For the total population, including non-centrally reviewed patients, evacuation occurring in the first, second or third trimester was associated with a treatment rate of 13.9% (601 of 4,333), 10.8% (412 of 3,803) and 5.1% (9 of 177), respectively. In patientsfor whom a central pathologic review had been performed to confirm the diagnosis, the treatment rates were 27.7% (525 of 1,897), 27% (241 of 893) and 20% (2 of 10). The higher apparent treatment rates reflect an error in the denominator as we do not review all nontreated cases. In the total population, evacuation in the third trimester correlated with a reduction in risk of subsequent treatment (P<.001). Most of these late deliveries were induced (before adequate ultrasound), whereas the earlier pregnancies were mostly terminated via suction dilatation and curettage. CONCLUSION: There is no evidence that delayed evacuation/delivery of singleton CHM increases the risk of subsequently requiring chemotherapy.

Routine terminations of pregnancy--should we screen for gestational trophoblastic neoplasia?

After termination of pregnancy for non-medical reasons, the products of conception are often not routinely examined for gestational trophoblastic neoplasia. Between 1995 and 2001 we identified 15 women without and 36 women with a pathological diagnosis of gestational trophoblastic neoplasia at the time of their pregnancy termination. Women without a diagnosis were significantly more likely to have subsequent life-threatening complications of gestational trophoblastic neoplasia (four of 15 vs none of 36; p=0.003), and to require surgical intervention (15 of 15 vs one of 36; p<0.0001) and chemotherapy (nine of 15 vs two of 36; p<0.0001). All women should be screened for gestational trophoblastic neoplasia after termination of pregnancy.

Histopathological diagnosis of partial and complete hydatidiform mole in the first trimester of pregnancy.

The diagnosis of molar pregnancy is a continuing diagnostic problem for many practicing histopathologists who are required to examine specimens of products of conception, particularly since changes in gynecological management in recent years have resulted in uterine evacuation at earlier gestations. The aim of this review is to provide practical, up-to-date, diagnostically useful information regarding the histological diagnosis of molar disease in early pregnancy. Pathophysiological issues relevant to molar pregnancies, such as genetic abnormalities, will be briefly summarized, but nonhistopathological aspects of molar disease will not be covered in detail in this review.

The maternally transcribed gene p57(KIP2) (CDNK1C) is abnormally expressed in both androgenetic and biparental complete hydatidiform moles.

Hydatidiform mole (HM) is an abnormal gestation characterized by trophoblast hyperplasia and overgrowth of placental villi. The genetic basis in the vast majority of cases is an excess of paternal to maternal genomes, suggesting that global misexpression of imprinted genes is the common molecular mechanism underlying the genesis of this condition. Although most complete HM are androgenetic in origin, a rare, frequently familial, biparental variant has been described. Here we evaluate the expression of p57(KIP2), the product of CDKN1C, an imprinted, maternally expressed gene in a series of these rare, biparental complete HM (BiCHM). We observed dramatic underexpression of p57(KIP2) in BiCHM, identical to that seen in complete HM of androgenetic origin (AnCHM). The series included two sisters, both of whom had BiCHM. Genotyping of this family identified a 15 cM region of homozygosity for 19q13.3-13.4 similar to that found in three other families with recurrent BiCHM. These results demonstrate that BiCHM, like AnCHM, result from abnormal expression of imprinted genes. In addition we provide further evidence for a major control gene on 19q13.3-13.4 which regulates expression of imprinted genes on other chromosomes.