Placental site trophoblastic tumor is a rare gestational trophoblastic tumor (GTT) which develops from the placental implantation site and always occurs following pregnancy, voluntary termination of pregnancy (VTP) or miscarriage. The disease is MONDO_0020552 (placental site trophoblastic tumor). Also known as: PSST, placental site gestational trophoblastic tumor, placental site gestational trophoblastic tumour, placental site trophoblastic tumor (morphologic abnormality), placental site trophoblastic tumour (morphologic abnormality), placental-site GTT, placental-site gestational trophoblastic neoplasm, placental-site gestational trophoblastic tumor.