[Classification of US findings of ovarian masses in children].

The ultrasonographic findings of 25 lesions in 23 patients with surgically proven ovarian masses were reviewed. There were 10 cystic teratomas, two simple cysts, two follicular cysts, two mucinous cystadenomas, two NHL, one corpus luteum cyst, one hydrosalpinx, one serous cystadenoma, one yolk sac carcinoma, one dysgerminoma, one embryonal carcinoma, and one mixed form (yolk sac carcinoma, choriocarcinoma). All patients were less than 15 years old. We classified all cases into four patterns: cystic, cystic with mural nodule, mixed, and solid. Eight lesions of the cystic pattern included two simple cysts, two follicular, cysts and one corpus luteum cyst. The other lesions were benign, too. Nine lesions with the cystic with mural nodule pattern consisted of eight cystic teratomas and one mucinous cystadenoma. All lesions were benign. The mixed pattern was seen in four lesions, half of which were malignant, i. e., one embryonal carcinoma and one yolk sac carcinoma. Four lesions with the solid pattern were all malignant masses: one dysgerminoma, two NHL and one mixed form. In this classification, the cystic and cystic with mural nodule patterns are benign, while mixed and solid patterns are highly suggestive of malignancy.