| Type of tumor | Associated clinical features | Ultrasonographic appearance |
| Benign germ cell tumors |
| Mature cystic teratoma Also called: - Mature teratoma
- Dermoid cyst (dermoid)
- Benign cystic teratoma
| - Most common ovarian neoplasm in children
- Often discovered incidentally
- 20 to 25% present with abdominal pain
- May present with nausea
- Bilateral in up to 10%
- Associated with anti-NMDAR encephalitis
| - Complex (cystic with solid components: calcification, echogenic material, fat-fluid levels)
- May contain thick sebaceous fluid, hair, and calcium
- Mean tumor size 6.5 cm
|
| Gonadoblastoma | - Typically associated with gonadal dysgenesis in phenotypically female patients with a Y chromosome/Y chromosome fragment (eg, Turner syndrome [45XO/46XY])
- Bilateral in 40%
- May be associated with malignant germ cell tumor (dysgerminoma)
- Associated with disorders with mutation in the WT1 gene (eg, Frasier syndrome and Denys-Drash syndrome)
| - Solid mass with calcification
- May be too small to easily detect with ultrasonography
|
| Benign epithelial tumors |
| Serous and mucinous cystadenoma | - 10 to 20% of ovarian tumors
- Usually diagnosed after menarche
| - Serous: Large unilocular cystic masses without septations
- Mucinous: Multiloculated cystic mass
|
| Benign sex cord-stromal tumors |
| Thecoma-fibroma | - <2% of ovarian tumors in children and adolescents
- Associated with ascites and pleural effusion (Meigs syndrome)
- Associated with basal cell nevus syndrome (Gorlin syndrome)
- May produce estrogen or testosterone
| |
| Malignant germ cell tumors |
| Immature teratoma | - Approximately 10% of complex ovarian masses in girls
- Mean age at presentation: 10 years
- Usually presents with palpable mass, but may be asymptomatic or present with abdominal pain, nausea, and/or vomiting
- Associated with gonadal dysgenesis
- May be associated with mature cystic teratoma in contralateral ovary
| - Complex or completely solid
- May contain foci of fat and calcification
- Mean diameter 16 cm (range 5 to >40 cm)
|
| Dysgerminoma | - Most common malignant germ cell tumor; most common ovarian malignancy in children
- Usually occurs in adolescence/early adulthood (peak incidence 15 to 19 years)
- Bilateral in approximately 15%
- Associated with gonadal dysgenesis (develops within a gonadoblastoma)
| - Solid mass with regions of necrosis, hemorrhage, and speckled calcifications
|
| Malignant sex cord-stromal tumors |
| Juvenile granulosa cell tumor | - Majority of pediatric sex cord-stromal tumors
- Most occur in first or second decade
- Secrete estrogen (associated with breast enlargement and vaginal bleeding)
- Associated with menstrual irregularities
- Bilateral in <5%
- Associated with Ollier disease and Maffucci syndrome
| - Predominantly solid with cystic spaces or predominantly cystic with solid foci
- Mean tumor diameter 12.5 cm
|
| Sertoli-Leydig cell tumor | - 20% of pediatric ovarian sex cord-stromal cell tumors
- <0.5% of malignant ovarian tumors in children
- Approximately 50% occur in patients 11 to 20 years and 6% in those <11 years
- Most patients present with virilization or menstrual irregularities
- Associated with DICER1 syndrome
| - Variable (solid, solid and cystic, predominantly cystic)
- Well-circumscribed without ascites or calcifications
|
