FIGO anatomic staging for gestational trophoblastic neoplasia (GTN).
Disease confined to the uterus
GTN extends outside of the uterus, but is limited to the genital structures (adnexa, vagina, broad ligament)
GTN extends to the lungs, with or without known genital tract involvement
All other metastatic sites
FIGO: International Federation of Gynecology and Obstetrics.