A teratoma is a type of germ cell tumor that is believed to be present at birth.
These are well-encapsulated tumors that can contain tissue normally found in the brain, liver or lungs. In some cases there have been reports of hair, teeth and bones appearing in teratoma.
Teratoma may be classified as mature or immature. A mature teratoma is well defined and cystic. An immature teratoma is solid and malignant.
There is a condition called “fetus in fetu” that is a rare form of teratoma where the tumor resembles a fetus. Some teratomas secrete chemicals such as the “pregnancy hormone” human chorionic gonadotropin. With today’s technology a teratoma can be diagnosed in a fetus while it is still in the womb. They can also be diagnosed much later in life.
Several common types of teratoma include sacrococcygeal, ovarian, testicular, and mediastinal. Sacrococcygeal teratomas are found in newborns. Ovarian and testicular teratomas are found in the ovaries and testicles respectively. Mediastinal teratomas are found in the chest area.
Signs and Symptoms
Teratomas are often asymptomatic. Ovarian teratoma can grow very large and begin to interfere with a fetus when a woman is pregnant. They can either obstruct blood flow to the fetus or actually steal blood flow from the fetus. This can cause health problems with the fetus and potentially kill the fetus. Testicular teratomas often first appear as a mass or lump on the testicles. Mediastinal teratomas in the chest can begin to interfere with breathing.
Teratomas are diagnosed based on histology. They are often detected during a prenatal ultrasound or an MRI. Fine needle aspiration or a biopsy of the tumor cells can generally confirm a diagnosis.
The first line of treatment for teratoma is complete removal of the tumor. Due to the well-defined, encapsulated nature of these tumors and the fact that they are non-invasive, they are relatively easy to remove. Teratomas in the brain can be difficult due to their proximity to healthy tissues. Surgery is often followed up with chemotherapy for malignant teratoma.
As with many types of cancer the prognosis for those with teratoma varies greatly depending on the type of teratoma, the size and the location of the tumor. Where complete removal of the teratoma is possible prognosis is very good.
For some patients complete removal is not possible due to the proximity to healthy tissue. In these cases doctors can often remove the majority of the tumor and the patient should be closely monitored after that.