Placental site trophoblastic tumor and choriocarcinoma: an unusual presentation

BACKGROUND: Mixed trophoblastic tumor composed of choriocarcinoma and placental site trophoblastic tumor was diagnosed on histopathology slides review, is a very rare mixed tumor and cured after adjuvant chemotherapy. CASE PRESENTATION: Twenty-nine years old, Para 2 female presented with 4 months history of irregular vaginal bleeding after an uncomplicated vaginal delivery. Abdominal examination showed 14 weeks uterus with β-hCG level of 14,889 mIU/ml. Slides review confirmed the diagnosis of placental site trophoblastic tumor (PSTT). Patient underwent total abdominal hysterectomy and resection of anterior vaginal wall mass. Post operative (48 h) β-hCG level was 6016 mIU/ml. Final pathology showed mixed trophoblastic tumor composed of choriocarcinoma (CC) and PSTT. Adjuvant chemotherapy started and continued for three cycles after achieving normal β-hCG. CONCLUSION: PSTT is a rare disease and potentially curable. Differential diagnosis in women presented with vaginal bleeding and a uterine mass in the post partum period must include gestational trophoblastic disease.