Learn more about temporal bone tumors and how they are treated.
Temporal bones are located at the sides and base of the skull. The temporal bone in the ear area contains the middle and inner portions of the ear. Tumors affecting this area can be either non-cancerous (benign) or cancerous (malignant). It's a rare type of tumor that may affect the ear canal and the outer portion of the ear.
Temporal bone tumors may become large enough to cause issues with hearing that may include persistent pulsating sounds only detectable by the patient
They are often detected during a routine ear exam or when a patient experiences some degree of hearing loss
What Types of Cancer May Affect the Temporal Bone?
Squamous cell carcinoma (a common type of skin cancer), adenoid cystic carcinoma (a rare type of cancer that begins in glandular tissues), and ceruminomatous adenoid carcinoma are the forms of cancer that often affect the temporal bone in the ear area. In some instances, cancers spread from adjacent areas (metastasis), including glands near the ear canals, to the temporal bone. Basal skin carcinoma is the most common form of cancer that affects temporal bones.
What Causes Temporal Bone Tumors to Develop?
There are only a few hundred new cases of temporal bone cancer diagnosed each year in the U.S. The specific cause of tumors in this area of the ear isn't known. There's research suggesting a possible link with sun exposure with skin abnormalities or irritations of the outer ear. Genetic factors may also play a role in the development of any of the types of cancer that may affect the temporal bone in the ear area. Patients with chronic skin infections of the ear canal may be at an increased risk for developing a tumor.
Possible Signs of a Tumor
Tumors sometimes appear a white bumps on the outside of the ear. Additional signs of an abnormality may include a scaly patch of skin on the ear and drainage from the affected ear. Tumors may also develop within the ear canal, which could result in pain, hearing problems, or inner ear pain.
Treatment Options for Temporal Bone Tumors
Ear surgery is often the recommended treatment for tumors causing noticeable symptoms and affecting hearing. Prior to surgery, a CT scan or MRI is often done to identify the specific location and size of the tumor. A biopsy is usually done to determine if the growth is cancerous.
Removal is often done through the ear canal for tumors that are small. For larger tumors, an incision may need to be made behind the ear to access the affected area. Radiation therapy is sometimes done to treat any affected tissues not removed with surgery.
What Types of Surgery May Be Performed?
Removal of bone and related ear structures is sometimes necessary for tumors located in the part of the ear canal near the opening of the ear. This is referred to as a sleeve resection. The ear is typically reconstructed post-surgery with another surgical procedure.
A tumor located in the inner two-thirds of the ear canal may be accessed with a lateral temporal bone resection. Removal of several parts of the affected ear will also be necessary for this procedure. Lymph nodes, temporomandibular joints (jaw joints), and the parotid gland might also need to be removed. After it's confirmed that the cancer is gone, reconstructive surgery may be done.
A sub-total temporal bone section may be performed when the abnormal growth is situated behind the ear drum. It's a combination procedure that includes techniques and procedures used with a lateral temporal bone resection and remove of additional parts of the inner ear.
How Will Hearing Be Affected After Surgery?
The way hearing will be affected after surgery will depend on the type of procedure performed. For instance, sub-total temporal bone section is more complicated and may result in partial or total hearing loss. With small tumors removed through the ear, hearing isn't likely to be affected at all. Some patients may need to use a hearing aid following surgery that required removal of parts of the ear and reconstruction.
As is the case with most tumors in the ear area, there is no way such growths can be effectively prevented. What patients can do, however, is be mindful of any changes in hearing and have their ears checked during regular physical examinations. When detected early, temporal bone cancer tends to respond better to treatment, which is often less extensive and invasive when tumors are still small. Follow-up visits and regular ear exams are typically recommended after surgery to detect any signs of recurrence.