Salivary Gland Cancer

Salivary gland cancer refers to malignant tumors that start in your salivary glands. Your salivary glands are in your mouth and throat. They produce saliva (spit) that helps break down food.

Salivary gland tumors — both malignant (cancerous) and benign (noncancerous) — usually start in the parotid glands. These are located on both sides of your face, in front of your ears. Less often, tumors start in other glands, including:

• Submandibular glands, found just below your jawbone
• Sublingual glands, found under the floor of your mouth
• Minor salivary glands, located in several places in your mouth, nasal cavity and sinuses, as well as your voice box

When tumors form in these glands, they’re more likely to be cancerous than those that start in your parotid glands.

Still, salivary gland cancer in general is rare. It accounts for only about 5% of head and neck cancers. If you develop it, your treatment and outlook depend mostly on how early it’s detected and the type.

Types

Experts group salivary gland cancers based on the cell where cancer starts. They also consider how abnormal the cells look, or their “grade.” High-grade types have cells that look abnormal. They tend to grow fast. Low-grade types grow slowly. Intermediate grades are somewhere in between.

The two most common types account for about half of all diagnoses. They are:

• Mucoepidermoid carcinoma: These tumors may be slow- or fast-growing. Your provider will need to study the cancer cells to learn more.
• Adenoid cystic carcinoma: These tumors tend to grow slowly, but they commonly spread (metastasize). Often, they go away after treatment but then come back many years later.

Less common high-grade salivary gland cancers include:

• Anaplastic carcinoma
• Carcinoma ex-pleomorphic adenoma
• Malignant mixed carcinoma
• Salivary duct carcinoma
• Squamous cell carcinoma

Salivary gland cancers that are low- to intermediate-grade include:

• Acinic cell carcinoma
• Epithelial-myoepithelial carcinoma
• Polymorphic adenocarcinoma

There are even more rare types.

Symptoms of salivary gland cancer

The first sign is often a painless lump on a salivary gland. Other symptoms and signs include:

• Weakness or numbness in your face, neck, jaw or mouth
• Pain in your face, neck, jaw or mouth that won’t go away
• Trouble opening your mouth fully or moving your facial muscles
• Trouble swallowing
• Bleeding from your mouth
• Fluid draining from your ears

Salivary gland cancer causes

Experts don’t know what causes it. But they’ve found errors in genes that are common in certain types of salivary gland cancer. These errors cause cells to multiply out of control and form tumors. Left untreated, tumors can spread to other parts of your body. This is called advanced (or metastatic) cancer.

Learning about these gene errors helps researchers find treatments that target them.

Risk factors

Males over 55 are more likely to have this condition. Other risk factors include:

• Smoking
• Previous radiation therapy to your head or neck
• Viral infections, including Epstein Barr virus (EBV), human immunodeficiency virus (HIV) and human papillomavirus (HPV)
• Exposure to chemicals in certain industries, like rubber manufacturing and asbestos mining

How doctors diagnose this condition

Your healthcare provider will ask about your symptoms and review your medical history. They’ll check for a lump in your salivary glands and for swollen lymph nodes. If you have a lump, they’ll test to see if it affects the main nerve in your face.

You’ll also need:

• Imaging tests: A CT scan, MRI or ultrasound can show a tumor’s size and whether it’s grown into tissue. A PET scan or PET/CT scan can show if the cancer has spread.
• Biopsy: Your provider will remove a sample of the tumor to test for cancer cells. Procedures include a fine-needle aspiration and a core needle biopsy.

Staging

Healthcare providers stage cancer as part of your diagnosis. This helps them know which treatments will likely work best. They stage tumors that form in your parotid glands, submandibular glands and sublingual glands from I to IV. Stage I is early-stage cancer, while Stage IV is advanced.

• Stage I: Tumors are 2 centimeters (cm) or smaller.
• Stage II: Tumors are bigger than 2 cm but smaller than 4 cm.
• Stage III: Tumors are larger than 4 cm and/or tumors have spread to your lymph nodes.
• Stage IV: Tumors have invaded nearby tissue, like your facial nerve. More advanced stage IV cancers spread to places far from the tumor, like your lungs, liver or bones.

Providers use a different system to stage cancers that form in minor salivary glands.

How is salivary gland cancer treated?

The treatment you’ll need depends on the type of salivary cancer, its stage and your preferences. Treatments include:

• Surgery: Removing the tumor is the most common treatment. For early-stage or low-grade tumors, this may be the only treatment you need. Your provider may remove all of the affected gland if it contains a high-grade tumor.
• Radiation therapy: You may get radiation therapy after surgery to kill any remaining cancer cells. This reduces the chance of cancer coming back. Radiation may be the main treatment if surgery may damage an important structure, like your facial nerve.

A clinical trial may be the best treatment for salivary cancer that has spread or come back. These studies test the safety and effectiveness of new treatments. Experts are testing new treatment combinations to help people with advanced disease live longer. Treatments include:

• Chemotherapy: This treatment uses drugs to destroy cancer cells throughout your body. You may need it if the tumor is advanced or if it goes away and then comes back after treatment.
• Targeted therapy: These therapies target weaknesses in cancer cells to prevent tumors from growing. This treatment may help manage cancers with certain gene errors.
• Immunotherapy: This treatment helps your immune system find and attack tumor cells. It treats cancers that have spread or come back after surgery.

When should I see my healthcare provider?

You’ll see your provider during regular visits after treatment. Even if you’re disease-free, you’ll likely need frequent imaging and exams for the first two to four years. This is when most salivary cancers come back (recur). But you’ll need follow-ups afterward, too. Sometimes, salivary cancer recurs decades later.

But don’t wait for an appointment if you have signs of recurrence. Call your provider if you have:

• Mouth or throat pain
• Hoarseness
• Trouble swallowing
• Enlarged lymph nodes

Is salivary gland cancer curable?

Sometimes, it can be curable. Most people recover fully from early-stage salivary cancer when surgery gets rid of the entire tumor.

But the chance of a cure depends on the tumor type (including the grade) and the stage. Your health, the tumor’s location and other factors matter, too. Your healthcare provider will review these factors with you so you know what to expect.

What is the survival rate of salivary gland cancer?

According to a recent study, more than 95% of people with low-grade or stage I tumors are alive five years after their diagnosis. Nearly 65% of people with high-grade tumors treated with surgery are alive five years later. But the five-year survival rate drops to less than 10% when the cancer is stage IV.

Still, it’s important to keep in mind that these numbers don’t consider key factors unique to your diagnosis. For instance, they don’t factor in the specific type of salivary gland cancer. They can’t predict your life expectancy.

This is why it’s best to ask your healthcare provider about what to expect based on your situation.