Genetically Related Choriocarcinoma Developing 5 Yr after a Complete Hydatidiform Mole and Simulating a Cornual Ectopic Pregnancy

Persistent gestational trophoblastic disease can arise from any type of antecedent pregnancy, including molar and tubal pregnancies. While most cases of persistent gestational trophoblastic disease present within the first year following initial diagnosis, recurrence has rarely been reported many years after initial diagnosis. Distinguishing recurrence from a new independent lesion is clinically important. A 25-yr-old woman presented with a mass in the right uterine cornu that was discontiguous with the endometrial cavity and was associated with an elevated serum human chorionic gonadotropin level. She had a history of an invasive complete hydatidiform mole with lung involvement treated with chemotherapy 5 yr prior. Wedge resection of the right cornu was performed due to concern for a cornual ectopic pregnancy. Pathologic evaluation demonstrated a choriocarcinoma. Molecular genotyping confirmed the tumor as recurrent disease genetically related to the prior complete hydatidiform mole. She completed 4 cycles of EMA-CO therapy, and has been disease-free with undetectable serum human chorionic gonadotropin level for 2 yr.