Pineoblastoma is a rare, aggressive type of cancer that begins in the cells of the brain's pineal gland. Your pineal gland, located in the center of your brain, produces a hormone (melatonin) that plays a role in your natural sleep-wake cycle.
Pineoblastoma can occur at any age, but it tends to occur most often in young children. Pineoblastoma may cause headaches, sleepiness and subtle changes in the way the eyes move.
Pineoblastoma can be very difficult to treat. It can spread within the brain and the fluid (cerebrospinal fluid) around the brain, but it rarely spreads beyond the central nervous system. Treatment usually involves surgery to remove as much of the cancer as possible. Additional treatments may also be recommended.
Tests and procedures used to diagnose pineoblastoma include:
Imaging tests. Imaging tests can help your doctor determine the location and size of your child's brain tumor. Magnetic resonance imaging (MRI) is often used to diagnose brain tumors, and advanced techniques, such as perfusion MRI and magnetic resonance spectroscopy, may also be used.
Additional tests might include computerized tomography (CT) and positron emission tomography (PET).
- Removing a sample of tissue for testing (biopsy). A biopsy can be done with a needle before surgery or during surgery to remove the pineoblastoma. The sample of suspicious tissue is analyzed in a laboratory to determine the types of cells and their level of aggressiveness.
- Removing cerebrospinal fluid for testing (lumbar puncture). Also called a spinal tap, this procedure involves inserting a needle between two bones in the lower spine to draw out cerebrospinal fluid from around the spinal cord. The fluid is tested to look for tumor cells or other abnormalities. In certain situations, cerebrospinal fluid may instead be collected during a biopsy procedure to remove suspicious tissue from the brain.
Pineoblastoma treatment options include:
- Surgery to relieve fluid buildup in the brain. A pineoblastoma may grow to block the flow of cerebrospinal fluid, which can cause a buildup of fluid that puts pressure on the brain (hydrocephalus). An operation to create a way for the fluid to flow out of the brain may be recommended. Sometimes this procedure can be combined with a biopsy or surgery to remove the tumor.
- Surgery to remove the pineoblastoma. The brain surgeon (neurosurgeon) will work to remove the pineoblastoma with the goal of removing as much of the tumor as possible. But it's often impossible to remove the tumor entirely because pineoblastoma forms near critical structures deep within the brain. Most children with pineoblastoma receive additional treatments after surgery to target the remaining cells.
- Radiation therapy. Radiation therapy uses high-energy beams, such as X-rays or protons, to kill cancer cells. During radiation therapy, your child lies on a table while a machine moves around him or her, directing beams to the brain and spinal cord, with additional radiation to the tumor. Because there is a high risk the tumor cells can spread beyond the initial site to other areas of the central nervous system, radiation therapy directed to the entire brain and spinal cord is recommended for children older than 3.
- Chemotherapy. Chemotherapy uses drugs to kill cancer cells. Chemotherapy may be recommended after surgery or radiation therapy in children with pineoblastoma. In some cases, it's used at the same time as radiation therapy. For larger tumors, chemotherapy may be used before surgery to shrink the tumor and make it easier to remove.
- Radiosurgery. Technically a type of radiation and not an operation, stereotactic radiosurgery focuses multiple beams of radiation on precise points to kill the tumor cells. Radiosurgery is sometimes used to treat pineoblastoma that recurs.
- Clinical trials. Clinical trials are studies of new treatments. These studies give you a chance to try the latest treatment options, but the risk of side effects may not be known. Ask your doctor whether your child might be eligible to participate in a clinical trial.