Classification and staging of gestational trophoblastic tumors.

Standard terminology for the gestational trophoblastic diseases has been defined by the World Health Organization. An anatomic staging system has also been adopted by FIGO, but it has not yet been widely utilized by American and European centers which prefer to determine therapy and report results based on risk grouping or prognostic scoring. Appropriate work-up of gestational trophoblastic tumors should be based on an understanding of the biology and natural history of the disease, that allows for efficient and cost-effective determination of the extent of spread and optimal therapeutic decisions.