The short answer
Cancers are usually named for the organ or tissue where they start and the kind of cell involved. A cancer keeps its original name even after it spreads, which is why breast cancer that spreads to the lung is still breast cancer.
Cancers are usually named for where they start, not where they spread.
Many names describe the type of cell: carcinoma, sarcoma, leukemia, lymphoma.
A cancer that spreads keeps the name of the place it began.
Breast cancer that spreads to the lung is still breast cancer, not lung cancer.
Watch: Why breast cancer in the lung is still breast cancer
45 sec · Captioned · Why breast cancer in the lung is still breast cancer — and why the name guides treatment.
Educational only — this video explains general report language and is not medical advice. Only your care team can say what a result means for you.
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The full explanation.
The simple version
Cancer names can sound complicated, but they follow a pattern. Most cancers are named for where they start and the kind of cell involved. Once you know the pattern, the names make more sense.
Named by cell type
Many cancer names describe the type of cell:
- Carcinoma starts in cells that line organs and skin. It is the most common type.
- Sarcoma starts in bone or in soft tissue such as muscle or fat.
- Leukemia starts in blood-forming cells.
- Lymphoma starts in the lymph system.
The name stays with the origin
A cancer keeps the name of where it began, even after it spreads. Breast cancer that spreads to the lung is metastatic breast cancer, not lung cancer. The cancer cells are still breast cells.
A cancer is named for where it started, not where it spreads.
Why it matters
The name tells doctors what kind of cell the cancer came from. That helps predict how it will behave and which treatments are likely to help. It is why treatment for metastatic breast cancer follows breast cancer guidelines, even when the tumor is in the lung. Under a microscope, those cells still look like breast cancer cells, not lung cells.
Sources
Words to know
Tap any term to see what it means.
Common questions
How are cancers named?
Most cancers are named for the organ or tissue where they start and the type of cell involved. For example, a cancer that starts in the lining of the colon is a colon carcinoma.
What do carcinoma, sarcoma, leukemia, and lymphoma mean?
Carcinomas start in the cells that line organs and skin; sarcomas start in bone or soft tissue; leukemias start in blood-forming cells; and lymphomas start in the lymph system.
Does a cancer's name change if it spreads?
No. A cancer keeps the name of where it began. Breast cancer that spreads to the lung is called metastatic breast cancer, not lung cancer, because it is still made of breast cancer cells.
Why does the name matter?
The name tells doctors what kind of cell the cancer came from, which helps predict how it will behave and which treatments are likely to work.
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Last updated: 2026-08-11Next planned review: 2028-07-07
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Cancer Explained does not originate medical claims. Every page restates guidance already published by the National Cancer Institute, the CDC, the USPSTF and the FDA, in plain language, with the source cited so you can check the original yourself. AI does the translating and organizing; automated checks test claims, citations, clarity and safety before anything publishes. We do not employ clinicians and do not intend to — our work is translation and navigation, not clinical judgment. Nothing here is personal medical advice, and no page can account for your particular situation.
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How this page was created
Cancer Explained does not originate medical claims. Every page restates guidance already published by the National Cancer Institute, the CDC, the USPSTF and the FDA, in plain language, with the source cited so you can check the original yourself. AI does the translating and organizing; automated checks test claims, citations, clarity and safety before anything publishes. We do not employ clinicians and do not intend to — our work is translation and navigation, not clinical judgment. Nothing here is personal medical advice, and no page can account for your particular situation.
Editorial status: Source checked — This page was written with AI assistance and checked line by line against the sources listed on it. That confirms the sources support what the page says. It is not a medical review, and it does not confirm the page is complete or right for your situation.
Human medical review: not completed. Pages here are not signed off by a clinician before they publish. That is not an oversight we are quietly working around: we restate published guidance and cite it, so the authority belongs to the source rather than to us, and every page names where its claims come from — you can verify us instead of trusting us. Where a volunteer clinician has reviewed a page, their name and credentials appear on it; where no name appears, no clinician has checked it. We are glad to have reviewers and are recruiting them, and we do not hold pages back waiting for one. Use this site to understand your situation and to ask better questions of the people treating you.
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