Recognition of placental site trophoblastic tumor (PSTT) began in the late 1970s to early 1980s, although similar lesions had been documented in the literature for over a century. The earliest description of the lesion was made by Von F. Marchand in 1895, who referred to it as “atypical chorioepithelioma.” Kurman, Scully, and Norris brought the lesion to wider attention in 1976, referring to it as “trophoblastic pseudotumor” based on 12 cases of a trophoblastic lesion involving the endomyometrium. In 1981, Scully and Young recognized that the lesion was, in fact, a bona fide malignant neoplasm, as 2 of 14 previously unreported cases had a fatal outcome due to metastasis. As a result, the term “placental site trophoblastic tumor” (PSTT) was proposed to replace “trophoblastic pseudotumor.” The term “placental site” was chosen because the proliferating cells had morphological features of implantation site trophoblast in a normal pregnancy. In the following year, Young formally adopted the name in his authoritative review of 42 cases, which was later accepted by the WHO.