What Is Mucoepidermoid Carcinoma?

Written by Rachel Reiff Ellis
Medically Reviewed by Melinda Ratini, MS, DO on June 17, 2025
8 min read

Mucoepidermoid carcinoma is the most common type of salivary gland cancer, but it’s rare. Only 1% of head and neck tumors are salivary gland cancer.

Your salivary glands are small organs that make saliva in your mouth and throat. They’re made up of different types of cells. Salivary gland cancer can start in any of them. Your outcome depends on where the cancer is and whether it’s spread.

Where is mucoepidermoid carcinoma located?

Most often, it happens in your parotid glands. Those are the largest of three types of salivary glands. You have two of them – one on each side of your face, just below your skin in front of your ears. 

Less commonly, you can get mucoepidermoid carcinoma in the submandibular glands. This pair of glands is just below your jaw on either side of your face.  

You can also get mucoepidermoid carcinoma in the minor salivary glands inside your mouth on your:

  • Lips
  • Palate (roof of your mouth)
  • Tongue
  • Cheek lining
  • Retromolar trigone (triangular area of tissue behind your last molar on your bottom jaw)

Very rarely, mucoepidermoid carcinoma can also happen in your:

  • Eustachian tube inside your ear
  • Thyroid
  • Breast
  • Lungs 
  • Jawbone
  • Nasal cavity
  • Throat

Doctors don’t know what makes mucoepidermoid carcinomas happen. Researchers are still studying what may be behind the disease. But they have been able to figure out some of the things that raise your risk of getting this type of cancer. Not everyone who gets mucoepidermoid carcinoma has a risk factor for it. 

In general, tumors happen when changes happen in DNA. DNA tells cells when to grow, multiply, and die. The changes in the DNA disrupt this normal messaging, and cells multiply quickly and keep living when they should die. These changes can cause cancer, which invades and destroys healthy body tissue. 

Certain things in your health history may raise your chances of having mucoepidermoid carcinoma. 

"Though the exact cause of mucoepidermoid carcinoma is unknown, people with a history of radiation to the head and neck or with chronic inflammation of salivary glands may be at higher risk of developing [it]," says Deepa Danan, MD, vice chair of clinical operations in the Head and Neck-Endocrine Oncology Department at Moffitt Cancer Center in Tampa, Florida.

People assigned female at birth are slightly more likely than males to get this type of cancer. Your risk goes up with age, most notably after age 55. 

Other risk factors include:

  • Smoking
  • Drink alcohol frequently
  • Viral infections such as Epstein-Barr, HIV, or human papillomavirus
  • Workplace exposure to rubber manufacturing materials, asbestos, and nickel

Some studies say a diet low in vegetables and high in animal fat may raise your chances. But more research is needed.

It usually begins as a painless lump in your mouth or jaw. Typically, these tumors grow slowly. But in some cases, they grow quickly. You may develop tenderness and other signs as it expands.

"An early sign of mucoepidermoid carcinoma could be a lump in the salivary gland in front of the ears, below the jawbone, or along the lining of the mouth or roof of mouth, [which is where your] parotid glands, submandibular glands, or minor salivary glands [are]," says Danan.

Other symptoms you might notice include:

  • Pain in your mouth, cheek, jaw, ear, or neck that does not go away
  • A recent difference between the size and/or shape of the left and right sides of your face or neck
  • Numbness in part of your face
  • Weakness of the muscles on one side of your face
  • Trouble opening your mouth widely
  • Trouble swallowing

Cancer in salivary glands isn’t common, but you can often find it early if you pay attention to these symptoms and tell your doctor right away.  

Your doctor will ask you about any health issues you’ve been having and for how long. They’ll also want to know your medical history to check for any risk factors for mucoepidermoid carcinoma.

They’ll feel any areas that may have lumps from mucoepidermoid tumors. This may include your mouth, the sides of your face, and around your ears and jaw. They’ll also feel for any lymph node swelling in your neck.

If any of these signs point to possible mucoepidermoid carcinoma, you’ll need to see a specialist of the head and neck, also called an otolaryngologist, or ear, nose, and throat doctor (ENT). This specialist will have tools for looking at the areas of concern in more detail. 

You might need tests such as: 

  • Blood tests. There is no blood test to diagnose mucoepidermoid carcinoma, but a blood test can help your doctor get a sense of your overall health and immune system function.
  • Biopsy. A doctor removes some cells, fluid, or tissue from an area where they suspect cancer and sends them off for testing in a lab to look for cancer cells. 
  • Imaging. You may have X-rays, a computed tomography (CT) scan, magnetic resonance imaging (MRI) scan, ultrasound, or positron emission tomography (PET) scan so that your doctor can look more closely at an area that could be cancer, and see if and how far it’s spread. These imaging techniques all use different methods to make pictures of the inside of your body. 

Doctors use several systems to grade mucoepidermoid carcinoma:

  • AFIP (Armed Forces Institute of Pathology) 
  • Brandwein
  • Modified Healey system
  • MSK (Memorial Sloan Kettering) 

These systems use points to give tumors a score. Each system uses different terms for grading and measures different indicators to make their score. Overall, they do the same job: give your doctor an idea of how to treat and manage your cancer. 

"This classification helps predict how aggressive the tumor may behave," says Danan.

Low-grade mucoepidermoid carcinoma

If your doctor classifies your mucoepidermoid carcinoma as low-grade, typically this means the cancer cells look similar to the cells around them (less abnormal) and grow more slowly. 

Intermediate-grade mucoepidermoid carcinoma

This grade of mucoepidermoid carcinoma is a mix between low- and high-grade, which means there is a mix of less abnormal cells and more abnormal cells. 

High-grade mucoepidermoid carcinoma

If your doctor classifies your mucoepidermoid carcinoma as high-grade, typically this means the cancer cells look very abnormal compared to the cells around them, and they tend to grow more quickly. 

There are several approaches to mucoepidermoid treatment, but the main approach is surgery to remove the tumor. 

Mucoepidermoid carcinoma surgery

Surgery is what doctors call "first-line" treatment – or, in other words, the "go-to" treatment for mucoepidermoid carcinoma. The goal of surgery is to get rid of all cancer cells in the area. This may mean removing not just the tumor, but some of the surrounding salivary gland and soft tissue, too. 

"The extent of surgery and need for reconstruction depend on the size, location, and grade of the tumor," says Danan.

Surgery on your parotid gland – where mucoepidermoid carcinoma most often happens – can sometimes be a tricky operation because an important nerve in your face called the facial nerve runs through the gland. This nerve controls movement of your facial muscles, some of your taste ability, the ability to make tears and saliva, and some of your sensation on the skin on the same side of the face.

Radiation and chemotherapy

If the size or location of your tumor makes it difficult for your doctor to remove it with surgery, they may suggest you use radiation, chemotherapy, or both to destroy cancer cells and slow their growth. 

Radiation therapy involves pointing a ray that's much like an X-ray at the spot where your cancer is. You don’t feel it when it’s happening, and each session only takes a few minutes, but it can cause some side effects such as red, sore, burned skin; sores; dry mouth; and hoarseness. 

Doctors don’t tend to choose chemotherapy for treating salivary gland cancers because it doesn’t typically work well. Chemotherapy is a medication you take by IV or mouth that goes through your whole body and destroys fast-growing cells, so the side effects are often more severe than with radiation. Your doctor may choose this route if your cancer has spread (metastasized) to distant organs or if surgery and radiation can’t keep it under control.

How well you can treat and manage your mucoepidermoid carcinoma will depend on its location, spread, and other things. But on the whole, this type of cancer – especially at lower grades – has a good outlook. 

"The prognosis for low-grade mucoepidermoid carcinoma is excellent, and for high-grade is dependent on the stage of tumor," says Danan. "Prognosis improves with early detection and intervention, so it's important to see a head and neck surgeon for evaluation as soon as there is concern."

Mucoepidermoid carcinoma is rare, but it’s the most common type of salivary gland cancer. Doctors don’t know its exact cause. Symptoms may include a painless lump near your jaw or mouth, facial numbness or weakness, and trouble swallowing. Your prognosis is generally good for low-grade tumors, but varies for intermediate and high grade cases, depending on how early the cancer is found.

What is the survival rate for mucoepidermoid carcinoma?

It depends on the grade of your tumor. The five-year survival rate for low-grade tumors is 92% to 100%. For intermediate-grade tumors, it’s 62% to 92%. The survival rate for high-grade tumors is up to 43%. 

What’s the cause of mucoepidermoid carcinoma?

Doctors aren’t sure. But risk factors include prior radiation to your head and neck, chronic inflammation of your salivary glands, smoking, viral infections such as Epstein-Barr or HIV, and workplace exposure to rubber manufacturing materials, asbestos, and nickel.

Can mucoepidermoid carcinoma be cured?

Sometimes. Low-grade tumors of this cancer have a high chance of treatment success. 

What’s the most common location for mucoepidermoid carcinoma?

It’s most often in your parotid glands, which are the largest of your salivary glands.