RT Book, Section A1 Hoffman, Barbara L. A1 Schorge, John O. A1 Halvorson, Lisa M. A1 Hamid, Cherine A. A1 Corton, Marlene M. A1 Schaffer, Joseph I. SR Print(0) ID 1171663822 T1 Gestational Trophoblastic Disease T2 Williams Gynecology, 4e YR 2020 FD 2020 PB McGraw-Hill Education PP New York, NY SN 9781260456868 LK obgyn.mhmedical.com/content.aspx?aid=1171663822 RD 2024/10/10 AB Gestational trophoblastic disease (GTD) refers to a spectrum of interrelated but histologically distinct tumors originating from the placenta (Table 37-1) (Hui, 2014a,b). These diseases are characterized by a reliable tumor marker, which is the β-subunit of human chorionic gonadotropin (β-hCG), and have varied tendencies for local invasion and spread.