Types of salivary gland cancer

The type of salivary gland cancer means the type of cell the cancer started in. There are many types of salivary gland cancers. This is because salivary glands are made up of different kinds of cells. They can be benign (non cancerous) or cancerous.

Most salivary gland cancers start in the parotid glands. The rest start in the submandibular glands, the sublingual glands or the minor glands.

As well as the 3 major pairs of salivary glands we have over 600 smaller, minor salivary glands throughout the lining of the mouth and throat.

Benign tumours

Most tumours of the salivary gland are not cancer. These are called benign tumours. This is especially so for parotid cancer where 3 out of 4 tumours (75%) are benign.

There are different types of benign tumours. The most common type are pleomorphic adenomas and are usually slow growing. Your doctor is likely to suggest surgery to remove these as there is a small risk of a cancer developing within the tumour.

You might have a course of radiotherapy if your benign tumour is likely to come back again.

Cells of the salivary glands

The salivary glands are made up of a number of different types of cells. Acinic cells make and release saliva. Mucoepidermoid cells line the gland.

The type of cancer you have is named after the type of cell the cancer started in. The doctor needs to take a biopsy and a specialist looks at the cells under a microscope before they can tell which type it is.

Your doctor tells you which salivary gland is affected and the cell type.

Mucoepidermoid carcinoma

Mucoepidermoid carcinomas are the most common type of salivary gland cancer. 

Mucoepidermoid cells are the lining cells of the salivary glands. Cancers of this type form tiny, mucous filled cysts. Most of these cancers develop in the parotid gland but they can also develop in the submandibular glands. They can also develop in the minor salivary glands.

Most mucoepidermoid cancers are slow growing but they can sometimes be fast growing. 

Acinic cell carcinoma

Acinic cell carcinomas are slow growing. These cancers develop in the acinar cells which produce saliva.

They tend to develop in younger people than most other salivary gland cancers. 

Adenoid cystic carcinoma

Adenoid cystic carcinoma is a common type of salivary gland cancer. It usually affects the minor salivary glands but can also occur in the major salivary glands. 

They are usually slow growing but can sometimes come back after treatment. 

Adenocarcinoma

Adenocarcinomas are rare cancers of the salivary gland. They develop in the epithelial cells. These are the lining cells of the body.

They can develop in the major or minor salivary glands.

Malignant mixed cancers

Malignant mixed cancers have more than one type of cancer cell. They are similar to the most common benign tumour of the salivary gland (pleomorphic adenoma).

A small number of people who have a benign tumour go on to develop a malignant mixed cancer. This is also called carcinoma ex-pleomorphic adenoma (Ca ex PA). 

Low grade polymorphous cancers

Polymorphous means the cancer has a variety of different growth patterns when looked at under a microscope. These are rare, slow growing cancers.

They usually affect the minor salivary glands. 

Other types

There are a number of other even rarer types of salivary gland cancer including:

• squamous cell carcinoma
• lymphoepithelioma
• anaplastic carcinoma
• undifferentiated carcinoma

These tend to develop later in life and are usually fast growing cancers.

Treatment

Your treatment depends on which gland the cancer started in.