Placental site trophoblastic tumor
Introduction
Rare tumor derived from intermediate trophoblast of implantation site
(not from villous trophoblast as choriocarcinoma).
Clinical signs
- women in reproductive years
- abnormal bleeding resembling spontaneous abortion is a common clinical presentation
- hCG titers are generally low (in contrast to choriocarcinoma)
- prognosis:
- usually benign
- 15% of reported cases show aggresive behaviour with disseminated metastases
Histology
- monomorphic pattern: intermediate trophoblastic cells, fibrinoid, necrosis
- tumor cells extensively infiltrate the endometrium and myometrium