Pineal gland tumor

A pineal gland tumor is a tumor that starts in that gland, which sits inside the brain. It is a primary brain tumor, meaning a mass of abnormal cells that forms in the brain itself. The pineal gland is an endocrine gland, one of the glands that make hormones, the body's chemical messengers that travel through the bloodstream. In adults, these tumors are rare.

Here is what goes on inside. The tumor can destroy brain cells directly, but it can also harm them in other ways: through the inflammation it triggers, by pushing on other parts of the brain, and by raising the pressure inside the skull. Think of a covered pot filled to the brim: if something starts taking up space inside, it squeezes everything around it, and the pressure in the whole pot goes up.

One example is pineoblastoma, a cancer of the pineal gland. It is more likely to develop in people with hereditary retinoblastoma. Retinoblastoma is a cancer of the eye, and it is called hereditary when it is tied to a genetic change, called a mutation, that is present in every cell of the body.