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What is A case of Gestational trophoblastic neoplasia is detected to have lung metastasis. She should be staged as and explain in detail?
FIGO staging system of GTN: Stage I: Disease confined to the uterus Stage II: Gestational trophoblastic tumor (GTT) extends outside of the uterus but is limited to the genital structures (ovary, tube, vagina, and broad ligament) Stage III: GTT extends to the lungs, with or without known genital tract involvement Stage IV: All other metastatic sites