from 89 cases of invasive mole , collected by our department since 1948 , 12 ( 13.5 % ) cases without preceding hydatidiform mole ( group a ) were taken out , and their clinical data and histological observations were studied in comparison with those preceded by hydatidiform mole ( group b ) in the remaining 77 ( 86.5 % ) , with the following results : 1 .
C0008493
invasive mole
C0020217
hydatidiform mole