- Etiology:
— Mature type – composed of fully differentiated adult-type tissues with absent or low mitoses
— Immature type – fetal-type incompletely differentiated tissues
— Malignant type – contains cancerous tissues such as sarcomas and carcinomas and other embryonal malignancies, malignant yolk sac endoderm can be aggressive component of teratomas - Imaging:
— Characteristically involve midline, nearly always heterogenous, often contain fat
— Heterogenous appearance due to presence of fat, cysts (mucous-laden), calcium (bone and chondorid nodules), soft tissues
— Enhancing soft tissues present in all types of tumors with enhancement of capsule and heterogenous enhancement of soft tissue components - DDX:
- Complications:
- Treatment:
- Clinical: patients with malignant teratomas may have elevated levels of AFP or beta-HCG in serum and or CSF, 90% of teratomas are found in < 20 years with most 10-12 years old,
80% occur around third ventricle and thus most symptoms are due to hydrocephalus and increased intracranial pressure
Congenital teratoma
- Intracranial teratomas are rare, accounting for 0.5-2.0% of intracranial tumors
- Comprise 50% of congenital brain tumors (those presenting in first 60 days of life)
- Typically benign tumors containing elements of all 3 germinal layers: ectoderm, mesoderm, endoderm
— Develop from embryonic cells which become misinvolved during formation of primitive streak in 3rd week of life
— Some of these cells become misenfolded as intracranial rests of tissue
Pineal teratoma
- Tissue rests typically found in midline, specifically pineal, suprasellar, 3rd ventricle regions
Suprasellar teratoma
- Differential diagnosis for T1 bright and T2 dark includes aneurysm, dermoid, lipoma, craniopharyngioma
Spinal teratoma
- Type I mainly external with small presacral component
- Type II external presentation with large intrapelvic component
- Type III external component with majority of tumor in pelvis and abdomen
- Type IV entirely presacral without externally visible component
- Sacrococcygeal region is most common site for teratomas in CNS
- Often associated with other abnormalities including anorectal and genital malformations, ventricular septal defect, hip dislocation, vertebral anomalies (spina bifida, sacral