Choriocarcinoma is differentiated from invasive mole (chorioadenoma destruens) by:
Choriocarcinoma can be considered a carcinoma of chorionic epithelium. The characteristic difference from hydatidiform mole is the absence of villous pattern.(refer pgno:172 sheila textbook of obstetrics 2 nd edition)
Presence of high titre of urinary chorionic gonadotrophin
Presence of cannon ball shadow in the lungs
Absence of villi structure on histological examine of the lesion
All of the above
General obstetrics