Skull Base Tumors
Behind the eyes and nose is the area of the brain called the skull base. Tumors that arise in that area are tricky to treat because they may lie very close to nerves and blood vessels, which can affect body functioning. Some may be inside the skull; others outside. Tumors may originate there (primary tumors) or metastasize from another organ to the brain.
Gaining access to these tumors for treatment is becoming easier with new approaches, including minimally invasive endonasal endoscopic surgery, in which the surgeon approaches the tumor through the nose without facial or head incisions. Alternatively, depending on the tumor location, the surgeon may go in through the eyebrow or from behind the ear. Many brain tumors and other conditions affect the skull base and are mostly primary in nature. These include:
Pituitary adenomas: Pituitary adenomas are tumors that occur in the pituitary gland, part of the skull base area, and are generally divided into two broad categories: functioning and non-functioning. More rarely, we can get pituitary cancers in this region, which are malignant counterparts of adenomas. See more information in pituitary tumors.
Nasal and paranasal sinus cancers: Sometimes the cancers present in the nose and paranasal sinuses can infiltrate into the intracranial cavity. These are usually treated by both the ENT and neurosurgeons.
Craniopharyngioma: This benign slow growing tumor begins near the pituitary and is very rare, making up less than 1 percent of all brain tumors. It’s more frequently seen in children as compared to adults.
Vestibular schwannoma: This is an uncommon, benign and usually slow-growing tumor that develops in the vestibular nerve. Because branches of this nerve directly influence one’s balance and hearing, pressure from a neuroma can cause hearing loss, ringing in the ear and unsteadiness. Most of the cases are sporadic. However, when present bilaterally, it raises concern for neurofibromatosis 2.
Bone tumors: Rarely, bone tumors such as chondrosarcoma, chordoma, osteosarcoma and others can arise in the skull base. (See musculoskeletal extremity treatments)
Skull base tumors that originate in the brain or have spread from other organs (metastatic tumors) often require surgery, and may respond to radiation and chemotherapy approaches by themselves or in conjunction with surgery.