Is there uniformity in definitions and treatment of gestational trophoblastic disease in Europe?

Because gestational trophoblastic disease is rare, little evidence is available from randomized controlled trials on optimal treatment and follow-up. Treatment protocols vary within Europe, and even between different centers within countries. One of the goals of the European Organization for Treatment of Trophoblastic Diseases (EOTTD) is to harmonize treatment in Europe. To provide a basis for international standardization of definitions, treatment and follow-up protocols in gestational trophoblastic disease, we evaluated differences and similarities between protocols in EOTTD countries.

Members from each EOTTD country were asked to complete an online structured questionnaire comprising multiple-choice and multiple-answer questions. The following themes were discussed: incidence of gestational trophoblastic disease and gestational trophoblastic neoplasia, definitions, guidelines, classification system, treatment, recurrence, and follow-up.

Forty-four respondents from 17 countries participated in this study. Guidelines were present in 80% of the countries and the FIGO (Fédération Internationale de Gynécologie et d'Obstétrique) staging and risk classification was often used to estimate risks. Agreement about when to start chemotherapy for post-molar gestational trophoblastic neoplasia was present among 66% of the respondents. Preferred first-line treatments in low- and high-risk gestational trophoblastic neoplasia were methotrexate (81%) and EMA-CO (etoposide, methotrexate, actinomycin D, cyclophosphamide, vincristine) (93%), respectively. The definition of human chorionic gonadotropin normalization after hydatidiform mole evacuation was two consecutive normal values for nine countries. The FIGO definition of post-molar gestational trophoblastic neoplasia based on human chorionic gonadotropin plateau or rise was agreed on by 69% of respondents, and only 69% and 74% defined low-risk and high-risk disease, respectively, using FIGO criteria. There were major differences in definitions of recurrence, chemotherapy resistance and follow-up protocols among countries, despite EOTTD consensus statements.

This questionnaire provides a good overview of current clinical practices in different countries. Based on the survey results, it is clear that there are several gestationaltrophoblastic disease-related topics that need urgent attention within the EOTTD community to create more uniformity and to aid the development of uniform guidelines in Europe.