Successful treatment of placental site trophoblastic tumor in twin pregnancy without hysterectomy.

To the best of the authors' knowledge, no case of placental site trophoblastic tumor (PSTT) pertinent to twin pregnancy has yet been published. There are only few case reports concerning patients with PSTT who were successfully treated by fertility-sparing methods. A 29-year-old nulliparous woman was admitted to hospital in the 36th week of a twin pregnancy due to symptoms of preterm labor. She underwent a cesarean section, during which a 4-cm uterine mass was found and resected. Histopathology revealed PSTT. Eighteen weeks after the delivery an ultrasound scan displayed another intrauterine mass, 2 cm in size. In the material resected in hysteroscopy there was necrotic decidual tissue. Another 30 months of observation revealed no abnormalities. Even though PSTT is rarely diagnosed, it may cause significant diagnostic and therapeutic problems.