The short answer
Most uterine cancers are endometrial carcinomas starting in the lining of the uterus, and endometrioid carcinoma is the most common subtype. Other subtypes, like serous and clear cell carcinoma, and separate cancers called uterine sarcomas, need different treatment.
Most uterine cancers are endometrial carcinomas, starting in the uterine lining.
Endometrioid carcinoma is the most common subtype of endometrial carcinoma.
Serous and clear cell carcinoma are less common subtypes that can behave more aggressively.
Carcinosarcoma makes up about 3 percent of uterine cancers and has features of two cancer types.
Choose how you want to understand this
The full explanation.
The simple version
Most uterine cancer starts in the lining of the uterus. Doctors call that endometrial carcinoma. Most of those are one subtype, called endometrioid carcinoma. A few uterine cancers are sarcomas. Those start in the muscle wall instead.
Endometrial carcinoma subtypes
- Endometrioid carcinoma. The most common subtype. It is what most people mean by "uterine cancer."
- Serous carcinoma. Less common. It tends to grow and spread faster.
- Clear cell carcinoma. Also less common. It too can spread faster.
- Carcinosarcoma. About 3 percent of uterine cancers. It has features of two cancer types at once.
- Mixed and undifferentiated carcinoma. Less common patterns your pathologist may report.
In short: endometrioid carcinoma is the most common subtype. Serous, clear cell, and carcinosarcoma tend to spread faster.
Uterine sarcoma: a separate cancer
Sarcoma of the uterus is not the same disease. It starts in the muscle layer, called the myometrium. It can also start in the connective tissue. It does not start in the lining. Sarcoma is much less common than endometrial carcinoma. It follows its own path, often with different surgery and different drugs.
Why type and subtype matter
Endometrioid carcinoma found at an early stage often has a good outlook. Surgery alone may be enough. Some people need more treatment after surgery. Serous, clear cell, and carcinosarcoma are graded as high risk. They often spread to other parts of the body, so treatment is usually stronger. Sarcoma is managed on its own track. Knowing your exact type helps your team match the treatment to your cancer.
What to watch for
NCI lists these as reasons to see a doctor:
- Vaginal bleeding or discharge that is not a normal period.
- Any vaginal bleeding after menopause.
- Pain or trouble passing urine.
- Pain during sex, or pain in the pelvic area.
Bleeding after menopause is never normal. It often has a harmless cause, but it always needs checking.
When to get help sooner
- Call 911 or go to an emergency department if you have heavy vaginal bleeding that soaks through pads quickly, or bleeding leaves you faint, dizzy, or short of breath.
- Call your care team the same day if you have any vaginal bleeding after menopause, or severe pelvic pain.
- Call your care team within a day or two if you have bleeding or discharge between periods, pain with sex, or pain when passing urine that does not clear.
Sources
Words to know
Tap any term to see what it means.
Common questions
What is the difference between endometrial cancer and uterine cancer?
Endometrial cancer, which starts in the lining of the uterus, is the most common type of uterine cancer, so the terms are often used interchangeably. But uterine sarcoma, which starts in the muscle wall of the uterus, is a separate and much less common type also grouped under uterine cancer.
What is endometrioid carcinoma?
It is the most common subtype of endometrial carcinoma, an adenocarcinoma that starts in the gland cells of the uterine lining. Most people with endometrial cancer have this subtype.
Are serous and clear cell carcinoma serious?
These are less common subtypes of endometrial carcinoma that tend to be more aggressive and are sometimes treated more intensively than typical endometrioid carcinoma, even at an early stage.
What is uterine sarcoma?
Uterine sarcoma starts in the muscle layer or connective tissue of the uterus, rather than the lining. It is much less common than endometrial carcinoma and is treated differently.
Questions to ask your doctor
Being prepared helps you get the most out of your appointments. Save or print these questions.
Tap a question to save it to your list (kept on this device).
Speak With Trained Specialists & Human Navigators
Cancer Explained provides educational guidance, but does not replace trained specialists, social workers, or your medical team.
Talk to a trained cancer information specialist
Free, confidential assistance from NCI Cancer Information Service via phone, chat, or email.
Contact your oncology team
Locate after-hours contact numbers, portal messages, or urgent triage phone lines.
Find a patient navigator
Get one-on-one help with appointments, logistics, translation, and care coordination.
Find a genetic counselor
Discuss inherited mutation risk, family history, and genetic testing options.
Find an oncology social worker
Access emotional counseling, family support groups, and mental health resources.
Find a financial navigator
Locate copay assistance foundations, grant programs, and lodging/travel support.
Find a clinical-trial specialist
Search matching studies and speak with NCI trial information specialists.
Get urgent help
Immediate emergency guidance for fever (>100.4°F during chemo), severe pain, or shortness of breath.
Help Us Improve This Guide
Did this explanation answer your question and help you determine your next step?
Know someone who needs this?
Plenty of people are looking for something like this and do not know where to start. If this would help a friend or someone you love, send it on — we have written an opening line so you do not have to stare at an empty message. You can change every word of it.
Your message is written and sent in your own email or messaging app — we never see who you send it to, and nothing is added to any list.
Plain-language explanation of the published sources cited on this page. AI-assisted, source-checked, not clinician-reviewed.
Last updated: 2026-08-11Next planned review: 2027-08-03
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.
General education — varies by person. Answers genuinely differ between people. This page explains what commonly varies and points you to your care team 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.
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.
Read more about our editorial process, our use of AI, and our corrections policy.
Spotted a problem? Report an error — a factual mistake, broken or outdated source, confusing wording, or anything that seems unsafe. Please do not include names, medical record numbers, dates of birth, addresses, or other identifying medical information in your report.
After using this page, do you understand what to do next?
Anonymous — we only record the answer, never who gave it.
Related articles
Still have questions?
Educational answers, plain language
Free to print and share