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What is Staging of GTN with lung metastasis. and explain in detail?
Stage 1 Disease confined to uterus Stage 2 GTN extending outside uterus but limited to genital structure (adnexa, vagina, broad ligament) Stage 3 GTN extending to lungs with or without known genital tract involvement Stage 4 All other metastatic sites 0 1 2 4 Age (years) <= 39 > 39 Antecedent pregnancy Hydatidiform mole Aboion Term Interval between end of antecedent pregnancy sta of chemotherapy (month) <4 4-6 7-12 >12 Human chronic gonadotropin (IU/L) at the time of GTN diagnosis <103 103 - 104 104 - 105 >105 ABO groups 0 or A B or AB Largest tumor, including uterine (cm) <3 3 - 5 > 5 Site of metaslases Spleen, kidney GI tract Brain, liver Number of metastases 1 drug >= 2 drug