The purpose of this study is to reevaluate the prognostic factors by investigating the clinical and biological parameters concerned malignant gestational trophoblastic tumor in patients with hydatidiform mole.

From March 1995 to February 2000, 41 patients admitted to department of the Obstetrics and Gynecology, Yonsei University College of Medicine who were diagnosed with pathologically-proven gestational trophoblastic disease were selected. Parameters such as age, gravida, parity, presence of theca lutein cyst, ratio of uterine size to gestational age, hCG level, DNA ploidy, S-phase fraction were compared between malignant gestational trophoblastic tumor group and spontaneous remission group.

Considering the clinical prognostic factors, the patients were divided into two age groups; the first group consisted of those older than 40 years of age and the second control group consisted of those under 40. The number of patients older than 40 in the spontaneous remission group and malignant gestational trophoblastic tumor group were 4(15.4%) and 7(46.7%), respectively, showing a significantly higher number in the group over 40years. Other parameters such as gravida, parity, presence of theca lutein cyst, ratio of uterine size to gestational age, hCG level, DNA ploidy, S-phase fraction showed no statistically significant difference between the two groups.

The progression rate from hydatidiform mole to malignant gestational trophoblastic tumor was significantly higher in patients over 40 years of age. Therefore, more aggressive therapeutic approach should be considered in such patients.