Adenoid Cystic Carcinoma: Introduction

Approved by the Cancer.Net Editorial Board, 12/2021

ON THIS PAGE: You will find some basic information about this disease and the parts of the body it may affect. This is the first page of Cancer.Net’s Guide to Adenoid Cystic Carcinoma. Use the menu to see other pages. Think of that menu as a roadmap for this entire guide.

Adenoid cystic carcinoma (AdCC) is a rare form of adenocarcinoma. Adenocarcinoma is a broad term describing any cancer that begins in the glands or glandular tissue that lines some organs. Most often, AdCC is found in the salivary glands.

About the salivary glands

Salivary glands contain tissue that produce saliva. Saliva is important to the body because it:

  • Helps keep the mouth moist

  • Contains enzymes that begin breaking down food

  • Helps prevent infections of the mouth and throat

There are clusters of salivary glands in several places in the head and neck. Salivary glands are divided into 2 groups based on their size:

Minor salivary glands. The minor salivary glands are small clusters of salivary glans that can be found in these parts of the head and neck:

  • Palate: roof of the mouth

  • Nasopharynx: an air passageway at the upper part of the throat and behind the nose

  • Tongue base: the back third of the tongue

  • Mucosal lining of the mouth: the inner lining of the mouth; glands located here produce mucus

  • Larynx: the voice box

  • Trachea: the windpipe

Major salivary glands. There are 3 pairs of major salivary glands:

  • Parotid glands: the largest salivary gland found on either side of the face in front of each ear

  • Submandibular glands: found under the jawbone

  • Sublingual glands: located in the bottom of the mouth under the tongue

About adenoid cystic carcinoma

Cancer begins when healthy cells change and grow out of control, forming a mass called a tumor. A tumor can be cancerous or benign. A cancerous tumor is malignant, meaning it can grow and spread to other parts of the body. A benign tumor means the tumor can grow but will not spread.

In general, AdCC is a cancerous tumor that begins in glands found in the head and neck region. In rare cases, it can form in other parts of the body, including in the brain, breast, lung, or the uterus. Most often, AdCC starts in the salivary glands found in the lips, mouth, tongue, nose, throat, vocal cords, and part of the esophagus and windpipe. This part of the body is known as the "upper aerodigestive tract." AdCC is sometimes classified as a disease of the minor salivary gland, even though it may begin at other locations.

Besides being classified based on where the cancer begins, AdCC is also described based on what the tumor cells look like under a microscope. This is called the histologic variations of the tumor. The tumor can be classified as:

  • cylindroma: a tumor with tube-shaped cells

  • cribriform: a tumor with gaps between the cells, giving it the appearance of Swiss cheese

  • solid AdCC

When AdCC spreads, it tends to spread along nerves, known as perineural invasion, or through the bloodstream. It spreads to the lymph nodes in about 5% to 10% of cases. If AdCC spreads to another part of the body beyond the lymph nodes, it is called metastatic cancer. The most common place for AdCC metastases is the lung.

AdCC is known for having long periods of no growth, also called indolence, followed by growth spurts. But AdCC can behave aggressively in some people. This makes the course of AdCC unpredictable.

This guide covers AdCC. Learn more about other types of salivary gland cancers and other head and neck cancers in separate guides on this website.

The next section in this guide is StatisticsIt helps explain the number of people who are diagnosed with AdCC and general survival rates. Use the menu to choose a different section to read in this guide.