Changes in gestational trophoblastic tumors over four decades. A Korean experience.

OBJECTIVE: To review changes that occurred in gestational trophoblastic tumor (GTT) patients treated over four decades and to identify factors leading to the changes. STUDY DESIGN: A retrospective study of 287 cases treated during 1961-1967, 1975-1979, 1980-1986 and 1990-1994. The method of diagnosis, incidence and outcome in each decade and factors that may have had an influence, on incidence, outcome or both, were reviewed. RESULTS: Diagnosis shifted from pathologic (1960s) to clinical (1990s). The incidence per 1,000 births decreased from 4.4 (1960s) to 1.6 (1990s). The incidence showed a 26-fold increase in women aged 40 and over and 13.4-fold increase in women para 3 and over. The obstetric population showed a decrease in the high-risk group of greater age and higher parity. Assessment by the 1983 World Health Organization prognostic score showed an increase in low-risk and decrease in high-risk disease. Prognostic score changes are related to a decrease in GTT in older women, increase in GTT with a short interval and increase in nonmetastatic disease. Overall mortality decreased from 32.6% to 2.6%. CONCLUSION: The decreased incidence and improved outcome of GTT in Korea are related to improved medical care and to social, economic and educational changes.