What Is a Choroid Plexus Tumor?

Choroid plexus is tissue in the brain and is responsible for producing cerebral spinal fluid. This fluid travels through the four ventricles to be absorbed in central nervous system tissue. A choroid plexus tumor is a type of brain tumor that occurs when abnormal cells grow uncontrollably in the choroid plexus tissue. These tumors can be benign or malignant depending on the type. Choroid plexus papilloma and choroid plexus carcinoma are the two main types of choroid plexus tumors.

A choroid plexus papilloma is one of the first main classifications of a choroid plexus tumor. This type of tumor is benign. They grow much slower than cancerous tumors and commonly affect children younger than two years old. The tumor grows in the ventricle and eventually blocks the flow of cerebral spinal fluid. While the fluid reduction affects the central nervous system, the blockage can also cause dangerous intracranial pressure, called hydrocephalus.

Choroid plexus carcinoma is the term used to classify a choroid plexus tumor that is malignant. These cancerous tumors grow and spread rapidly. The tumor grows in surrounding tissue, and cancerous cells can travel through the cerebral spinal fluid to other areas of the body where they can create new growths outside of the brain. Hydrocephalus can often occur with these tumors, particularly if the flow of the spinal fluid is hindered. Choroid plexus carcinoma generally affects younger children, but it can occur at any age.

If left untreated, a choroid plexus tumor can be fatal. In most cases, however, this tumor can be successfully removed. Choroid plexus papilloma does not spread from its original location, but since choroid plexus carcinoma does spread a doctor must look for possible secondary tumors as well.

Surgical removal of a choroid plexus tumor that is benign is most successful and gives patients a high survival rate. For malignant tumors, especially with the presence of secondary tumors, surgical removal will not work on its own. Tumors can regrow. In these instances, chemotherapy or radiation therapy — sometimes both — are used to kill the abnormal cells and prevent new growth. If patients have hydrocephalus as a result of a tumor, a shunt may be used to allow the cerebral spinal fluid to flow properly while the patient undergoes treatment and/or surgical removal.