A to Z List of Cancers

Use the alphabet links to find and retrieve information about a particular type of cancer. (The A to Z list is also available in Spanish.)

A

Acute Lymphoblastic Leukemia (ALL)
Acute Myeloid Leukemia (AML)
Adolescents, Cancer in
Adrenocortical Carcinoma
        Childhood
AIDS-Related Cancers
        Kaposi Sarcoma
        Lymphoma
Anal Cancer
Appendix Cancer
Astrocytomas, Childhood
Atypical Teratoid/Rhabdoid Tumor, Childhood, Central Nervous System

NCI Dictionary of Cancer Terms

Welcome to the NCI Dictionary of Cancer Terms, a resource with 7,619 terms related to cancer and medicine.

Tips on Looking Up a Word or Phrase

In the search box, type the word or phrase you are looking for and click the "Go" button.

Click the radio button in front of the word "Contains" when you want to find all terms in the dictionary that include a word or set of letters. For example, if you type "lung" and select "Contains," the search will find terms such as "small cell lung cancer" as well as "lung cancer."

You can also click on a letter of the alphabet to browse through the dictionary.

The search box has an autosuggest feature. When you type three or more letters, a list of up to 10 suggestions will pop up below the box. Click on a suggestion with your mouse or use the arrow keys on your keyboard to move through the suggestions and then hit the Enter key to choose one.

Using the Escape key or clicking "close" within the autosuggest box closes the box and turns off the feature until you start a new search.

After you find your word or phrase, use the tabs under the search box to toggle between definitions in English and Spanish.

What Is Cancer

Defining Cancer

Cancer is a term used for diseases in which abnormal cells divide without control and are able to invade other tissues. Cancer cells can spread to other parts of the body through the blood and lymph systems.

Cancer is not just one disease but many diseases. There are more than 100 different types of cancer. Most cancers are named for the organ or type of cell in which they start - for example, cancer that begins in the colon is called colon cancer; cancer that begins in melanocytes of the skin is called melanoma.

Cancer types can be grouped into broader categories. The main categories of cancer include:

Carcinoma - cancer that begins in the skin or in tissues that line or cover internal organs. There are a number of subtypes of carcinoma, including adenocarcinoma, basal cell carcinoma, squamous cell carcinoma, and transitional cell carcinoma.
Sarcoma - cancer that begins in bone, cartilage, fat, muscle, blood vessels, or other connective or supportive tissue.
Leukemia - cancer that starts in blood-forming tissue such as the bone marrow and causes large numbers of abnormal blood cells to be produced and enter the blood.
Lymphoma and myeloma - cancers that begin in the cells of the immune system.
Central nervous system cancers - cancers that begin in the tissues of the brain and spinal cord.
(For definitions of other cancer-related terms, see NCI's Dictionary of Cancer Terms.)

To find out more about a specific type of cancer, see the A to Z List of Cancers or the list of Cancers by Body Location/System.