A paraganglioma is a tumor that appears in the temporal bones of the head or along the jugular vein in the neck. A tumor occurs when a group of nerve fibers called glomus cells grow and reproduce abnormally. Paragangliomas tend to grow slowly, and many people do not experience symptoms for several years after they begin to appear. Depending on the exact location of a paraganglioma, a person might experience pain, difficulty swallowing, and hearing or speaking problems. Treatment for paragangliomas usually involves surgery to remove the tumors and repair damaged nerve, muscle, and bone tissue.
Glomus cells are important sensory nerve cells that are found along blood vessels in many parts of the body, including the head and neck. A paraganglioma appears when glomus cells wildly reproduce and grow into a large, firm mass. Doctors are usually unsure of what triggers abnormal growth of glomus cells, but there is evidence that the condition is often inherited from one or both parents. Paragangliomas are most likely to affect people over the age of 45, but they can appear at any age. They are almost always benign, though a small percentage of paragangliomas turn cancerous over time and spread to other parts of the body.
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It is common for a paraganglioma to be asymptomatic, and many tumors are not detected until a person undergoes an exam for another condition. In some cases, however, a tumor can grow large enough to protrude outward in the neck or put pressure on the bones of the head. As a paraganglioma grows, a person might experience difficulty hearing, speaking, or swallowing. He or she might have chronic pain in the head or neck, and suffer from frequent spells of dizziness.
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Paragangliomas sometimes grow large enough to damage surrounding nerve fibers. Partial paralysis of the mouth, face, or neck is possible if nerves become pinched or severed due to a growing tumor. If a paraganglioma become cancerous, a person can suffer from a number of additional symptoms including fatigue, weakness, and nausea.
Doctors can diagnose paragangliomas by examining lumps in the neck, taking tissue biopsies, and examining the results of x-rays. Once a paragangioma is discovered, a physician usually recommends surgery to cut out the tumor and damaged tissue. Surgery is especially important if tissue biopsy results indicate that the tumor is cancerous. Surgical procedures are usually very effective, and most patients recover entirely within a few months. If permanent nerve damage has occurred, however, a patient may experience lifelong difficulties hearing or speaking.