5 Possible Causes for Lumps Behind the Ears

2. Ear infection or mastoiditis

A swollen lymph node behind the ear can also be a sign of an ear infection, especially if it’s accompanied by symptoms such as ear pain, hearing changes or fluid drainage. Ear infections happen when the tubes in your ears become blocked, whether from allergies, a sinus infection or even just the common cold.

If an ear infection isn’t treated, bacteria can spread to the bone just behind your ear, causing a serious condition called mastoiditis, Powers says. While mastoiditis is rare, it’s important to mention, he says, because if it isn’t treated, it can lead to complications such as hearing loss or meningitis.

That’s why it’s a good idea to see a doctor right away if you notice a lump behind your ear along with ear-related symptoms, Powers advises. Most of the time, ear infections are easily treated with antibiotics. But if mastoiditis is diagnosed, more intensive treatment or surgery may be necessary.

3. Other types of infection

Other types of infections that can cause the lymph nodes behind your ear to swell include:

• Skin infection: Skin infections can happen on the cartilage of your outer ear, known as the auricle. These infections, known as perichondritis, happen when bacteria infects an area of the ear that’s been injured, usually by something like a piercing, an insect bite or a burn.
• Dental problems: A tooth or gum infection or a dental abscess can trigger swelling in nearby lymph nodes. You might notice tooth pain, sensitivity to hot and cold food or a fever. 
• Scalp infection: If you also have itching, hair loss or scalp irritation, a scalp condition such as impetigo, scalp psoriasis or a fungal infection may be causing your lymph node to swell. 
• Salivary gland infection: These glands, located near your jaw, can trigger swelling if they become infected. Symptoms may include an abnormal taste in your mouth, a dry mouth, difficulty opening your mouth, fever and a squeezing pain in your mouth or face, often after eating. 

Dental and salivary gland infections are usually bacterial, so your doctor may prescribe an antibiotic to treat them. Scalp and skin infections, on the other hand, can be bacterial or fungal. Your health care provider would need to determine the cause to recommend appropriate treatment.

4. Cyst or abscess

Cysts are small saclike growths that can form anywhere on the skin, including behind the ear. Cysts behind the ear typically develop when dead skin cells and oil become trapped in a hair or sweat follicle on the skin. Cysts are usually painless and benign, but if they become infected, they can develop into abscesses.

Abscesses are large, pimple-like bumps that are filled with pus. They are typically painful and uncomfortable. While an abscess can form from an infected cyst, it can also form on its own. In either case, your doctor may recommend draining or removing it.

5. Tumor (benign or malignant)

A lump behind your ear can sometimes be a tumor, which is usually the biggest concern when evaluating a new growth, says Dr. Eleni Rettig, a head and neck surgeon at Brigham and Women's Hospital and Dana-Farber Cancer Institute at Harvard Medical School.

Scalp tumors and salivary gland tumors are the most common type that would show up behind your ear, Rettig says, and they can be benign (noncancerous) or malignant. Lymphoma, a blood cancer, can also present as a hard lump behind the ear, Rettig says. 

Tumors related to other types of head and neck cancer are more likely to appear as lumps under the ear lobe behind the jawbone, she says.

Unlike swollen lymph nodes caused by infection — which tend to be soft, tender and movable — tumors grow over time and are often painless, Rettig says. “If something is firm or does not move easily, those are particularly concerning features,” she says.

Older adults are at higher risk for tumors, so it’s crucial to see a doctor if you have a hard lump behind your ear or if it doesn’t go away, she says. Your doctor will likely recommend imaging and a biopsy to make a diagnosis.

“The take-home is that a lump in the head and neck for an older adult — behind or near your ear lobe — really needs to get checked out, unless it disappears within a week or two,” Rettig says.

When to see a doctor

No matter what kind of lump you have, it’s important to get it checked if something doesn’t seem right. You should see a doctor if:

• The lump is painful, red or hot
• It appears suddenly or seems to be growing
• It feels firm and doesn’t move and change when you touch it
• You have other symptoms like fever, ear or throat pain, skin changes, weight loss or extreme fatigue
• It lasts longer than two weeks
• You're simply concerned about it.