Types of Skull Base Tumors

Specialists at NYU Langone are experts at identifying the many types of skull base tumors. Many important nerves and blood vessels run through the skull base, which is why tumors that develop there can cause many different symptoms, depending on their location.

NYU Langone doctors determine the best treatment for you based on the type of tumor you have. Tumors in the skull base may be benign, meaning noncancerous, or malignant, meaning cancerous.

Benign Skull Base Tumors

Even though benign tumors are usually slow growing, they can become large enough to cause symptoms.

Meningiomas

Meningiomas occur in the meninges, the sheet-like layers of connective tissue that protect the brain and spinal cord. Most of these tumors are benign.

Symptoms depend on the location of the meningioma. The tumor may press on nerves, causing facial numbness or pain. It may also affect the optic nerve, interfering with vision; other cranial nerves; or the brain stem, which connects the brain to the spine.

Pituitary Tumors

These growths occur on the pituitary, a small gland located at the base of the brain that produces many hormones and controls other glands that produce hormones. There are many types of pituitary tumors. Some are small and may not cause any symptoms; others are large and can affect the eyesight in one or both eyes. These tumors can also create hormone disturbances that may affect growth, weight, sperm production, and ovarian function.

Acoustic Neuromas

An acoustic neuroma is a noncancerous brain tumor that develops on the nerve that runs between the inner ear and the brain. Also called vestibular schwannomas, acoustic neuromas develop in cells known as Schwann cells. These provide insulation, or myelin, for nerve cells.

Acoustic neuromas may cause hearing loss; tinnitus, or ringing in the ears; balance difficulties; or problems with facial movements and facial numbness as they grow and impinge on nearby nerves.

Other Nerve Sheath Tumors

Other types of tumors can develop in Schwann cells, which surround and protect nerves. They can affect the trigeminal nerve, the facial nerve, and the jugular foramen.

The trigeminal nerve is responsible for facial sensation and movements such as chewing. Trigeminal nerve schwannomas can cause facial numbness or pain or problems with chewing.

Facial nerve schwannomas can cause facial weakness, hearing loss, and balance problems, depending on their size. They can occur anywhere along the facial nerve, which runs from the brain stem and through the temporal bone—the part of the skull that sits over the inner and middle ear.

Schwannomas can also form in the jugular foramen, an opening in the skull base that carries nerves that help control vocal cord and throat muscles. Symptoms of jugular foramen tumors may include problems with swallowing and hoarseness of the voice.

Orbital Tumors

Orbital tumors occur in the eye socket, or orbit. They can affect eye movements and vision and also cause protrusion of the eyeball. Tumors that affect the orbit include hemangiomas, which are noncancerous tumors that develop from blood vessels; schwannomas, which develop from Schwann cells that protect the orbital nerve; and meningiomas.

The signs and symptoms of orbital tumors depend on their size and location within the orbit. Some orbital tumors can grow into the skull base by extending through the bone that separates the two areas.

Epidermoids and Dermoids

Epidermoids are noncancerous tumors that form while a baby develops in the womb. They are present at birth but because they are slow growing, they may not be detected in the skull base until adulthood. The tumors consist of squamous epithelial cells, which help create keratin, the protein that strengthens skin, hair, and nails.

Dermoid tumors also consist of squamous epithelial cells and are slow growing and form before birth. However, they also contain substances such as hair, teeth, skin, or fluid.

Juvenile Angiofibromas

These tumors form in the nasal cavity, the space behind the nose that helps form the front part of the skull base. These tumors are slow growing but can become large and cause symptoms, such as blockage of the nasal passages or frequent nosebleeds. Juvenile angiofibromas are rare and usually affect adolescent boys.

Cholesterol Granulomas

Cholesterol granulomas are benign cysts that consist of a fibrous outer coating and contain fluids, crystals of cholesterol—a waxy, fatty substance—or other fats. They can occur in the temporal bone, located at the skull base next to the inner ear. As they grow, they can cause hearing loss or damage to surrounding nerves.

Craniopharyngiomas

A craniopharyngioma develops near the pituitary stalk, a piece of tissue that connects the pituitary gland to the hypothalamus, an area of the brain that produces hormones. These tumors can grow and cause symptoms such as headache or vision problems. They may also cause hormonal problems, which can interfere with growth, puberty, fertility, and metabolism.

Glomus Jugulare Tumors

These tumors arise from the chemoreceptor cells, which are sensory cells, commonly located in the temporal bone. Depending on their size, these tumors may produce a rushing noise in the ear, hearing loss, and problems with speaking and swallowing.

Malignant Skull Base Tumors

Some malignant, or cancerous, skull base tumors grow more rapidly than benign tumors. They have the potential to spread to other areas of the body.

Chondrosarcomas

A chondrosarcoma is a type of cancer that starts in the cartilage at the junction of the bones of the skull base. These tumors can grow slowly or rapidly. Symptoms of chondrosarcomas depend on their location in the skull base and may include headache, ringing in the ears, and problems with vision, hearing, or balance.

Esthesioneuroblastomas

An esthesioneuroblastoma arises from cells in the olfactory nerves, which travel from the nose to the brain and control the sense of smell. This type of tumor occurs in the nasal cavity and can grow into the skull base.

An esthesioneuroblastoma can obstruct the nasal passages and cause nosebleeds, changes in the sense of smell, discharge from the nose, and pain. When advanced, it can spread to distant parts of the body.

Nasopharyngeal Carcinomas

A nasopharyngeal carcinoma develops behind the nose in the upper part of the throat, an area called the nasopharynx, which is located near the skull base. The nasopharynx carries air from the nose to the throat.

These tumors are usually made of squamous cells, which line the mucous membranes inside the mouth, throat, and nose. Nasopharyngeal carcinomas can enter the skull base as they grow, causing vision problems, hoarseness, headache, and facial pain.

Adenoid Cystic Carcinomas

Adenoid cystic carcinomas develop in the cells of the salivary glands, which form and secrete saliva. Salivary glands are located near the base of the skull. Symptoms of these tumors include pain, numbness, difficulty swallowing, and hoarseness.

Chordomas

A chordoma is a malignant tumor that can arise from the bones of the skull base. If it is small, it may not cause symptoms. Larger tumors may cause headache and problems with vision, hearing, walking, or balance. These tumors are often slow growing. Usually, they remain confined to the skull base but can spread to other parts of the body.