When deciding which treatments will be most effective for endometrial cancer, the stage of the cancer is one of the most important factors your doctor will consider. Stage is also used to predict survival rates. Endometrial cancer — also called uterine cancer — is assigned one of four stages, ranging from stage 1 through stage 4. Stages are sometimes written with Roman numbers, e.g., I, II, III, and IV.

Learning more about how endometrial cancer is staged, how it’s treated at different stages, and how stage affects survival rates will help you be better prepared for conversations with your doctor.

How Is Endometrial Cancer Staged?

If you have potential symptoms of endometrial cancer, your doctor will order tests to help confirm or rule out this diagnosis. These may include:

• Biopsy — A sample of tissue is taken from the endometrium (the mucous membrane that lines the uterus) to be examined by a pathologist (a doctor specializing in studying tissues under a microscope).
• Lymphadenectomy (lymph node dissection) — This surgical procedure checks if cancer has spread to the lymph nodes.
• Imaging tests — These include X-rays, MRIs, CT scans, and positron emission tomography (PET) scans.

Tumor, Node, and Metastasis

Your doctor will assess the results of the tests and scans described above and use a tumor staging system to determine the stage.

There are several different systems for staging cancer. One of the most common and useful ways is the TNM system, which takes into consideration the following.

• Tumor (T) — This describes the size of the tumor, how far it has grown into the uterus wall, and if it has affected any nearby body parts.
• Node (N) — This indicates whether the cancer has spread to the nearby lymph nodes in the pelvis or around the aorta (the largest artery in your body that carries blood from your heart to your abdomen and pelvis).
• Metastasis (M) — This indicates whether the cancer has metastasized (spread) to distant lymph nodes or organs.

Staging may not be complete until after your doctors look at the tumor and lymph nodes that are removed during surgery.

It’s important to note that stage is not the only detail about your endometrial cancer that factors into your treatment plan. Your doctor may also order biomarker testing to check for specific genes or proteins expressed by your cancer cells.

Stage 1

In stage 1 endometrial cancer, cancer cells are growing only in the uterus. While the cancer may have started to spread to the glands of the cervix, it hasn’t spread to the stroma (the connective tissue that supports the cervix), lymph nodes, or any other part of the body.

Stage 1 is broken down into two additional categories — 1A and 1B — based on the size and spread of the tumor.

In stage 1A, cancer cells are found in the endometrium and may have spread less than halfway through the myometrium (muscular layer of the uterus).

In stage 1B, cancer cells have grown halfway or more into the myometrium but haven’t spread to other parts of the body.

Treatment for Stage 1 for Endometrial Cancer

The standard treatment for stage 1 cancer is a hysterectomy with bilateral salpingo-oophorectomy — the surgical removal of the uterus, cervix, and ovaries. Surgery may be the only treatment needed for stage 1 cancer.

A person who wishes to have children in the future may choose to put off surgery to have a chance to become pregnant. These individuals can be treated with hormone therapy to help shrink the tumor until after they give birth.

Stage 2

In stage 2 endometrial cancer, the cancer has started to spread to the cervical stroma. Cancer in stage 2 is still only found in the uterus and hasn’t spread to other parts of the body.

Treatment for Stage 2 Endometrial Cancer

The recommended treatment for stage 2 includes a hysterectomy followed by radiation therapy. Your surgeon may conduct a radical hysterectomy, which entails removing the tissues next to your uterus (the upper part of your vagina) and the lymph nodes in your pelvis and around your aorta.

If cancer is found in the lymph nodes removed during surgery, your stage may be reassessed from stage 2 to stage 3C.

After surgery, your doctor may recommend chemotherapy or radiation therapy to prevent your cancer from coming back.

Stage 3

In stage 3, cancer has spread beyond the uterus but not outside the pelvis or to distant lymph nodes. Stage 3 is further broken down based on the extent that the cancer has spread within the pelvis.

In stage 3A, the cancer has spread to the serosa (the outer layer of the uterus) and/or the adnexa (the fallopian tubes and ovaries) — but not to any lymph nodes or distant sites.

In stage 3B, cancer has spread to the vagina or the parametrium (the fat and connective tissues surrounding and supporting the uterus) but not to any lymph nodes or distant sites.

In stage 3C, cancer has spread beyond the uterus and cervix but not inside the bladder or rectum. In this stage, the cancer has also spread to nearby lymph nodes. When the cancer has spread to the lymph nodes only in the pelvis, it’s called stage 3C1. When it has spread to the para-aortic lymph nodes (the lymph nodes around the aorta) but not to distant sites, it’s known as stage 3C2.

Treatment for Stage 3 Endometrial Cancer

Surgery, radiation therapy, and chemotherapy are standard treatment options for stage 3 cancer. Common chemotherapy drugs used include cisplatin (Platinol), carboplatin (Paraplatin), and paclitaxel (Taxol). Immunotherapy with pembrolizumab (Keytruda) or dostarlimab (Jemperli) may be an option if your cancer can’t be treated with surgery or radiation.

Stage 4

In stage 4 endometrial cancer, cancer has spread to distant sites of the body beyond your pelvis. If your cancer has spread to other parts of your body, it’s classified as stage 4, regardless of the tumor size or whether any lymph nodes are involved.

The closest organs to your uterus are your rectum and urinary bladder. When the cancer spreads beyond the uterus, it’s most often to these organs. When cancer has spread to the rectum or bladder but no other distant sites, it’s considered stage 4A. If cancer has spread to inguinal lymph nodes (lymph nodes of the groin), the upper abdomen, the omentum (the fatty tissue covering the organs in your abdomen), or any other organs, it’s known as stage 4B.

Treatment for Stage 4 Endometrial Cancer

In stage 4 cancer, the cancer has often advanced too far to be fully removed with surgery. Treatment of stage 4 endometrial cancer may include chemotherapy, radiation therapy, hormone therapy, immunotherapy, and targeted therapy. You may also consider participating in a clinical trial investigating new treatments.

Recurrent Endometrial Cancer

When cancer comes back after treatment, it’s called recurrent. The recurrence may happen in or near the same place it originally occurred or in another organ far from where the cancer originally occurred.

Recurrent cancer may be staged again — called restaging. The new stage is added to the previous stage but does not replace it. The stage that was assigned when you were diagnosed is still the most important for determining survival rates. Treatment options for recurrent or advanced (stage 4) cancer are similar.

Outlook by Stage

Your doctor may talk about the likely outcomes of your cancer — your prognosis — in terms of survival rates. Survival is often measured as five-year relative survival rates. This rate is the percentage of people with the same type and stage of cancer who live five years or more from the time of diagnosis.

In general, the earlier your endometrial cancer is diagnosed, the better your chances of surviving five years or more. Most endometrial cancers in the United States — up to 67 percent — are found at an early stage when the cancer is found localized in the area where it started, according to the National Cancer Institute Surveillance, Epidemiology, and End Results (SEER) Program. Almost 95 percent of females with localized endometrial cancer live five years or longer from the time of diagnosis, according to SEER.

Cancer that has spread to the lymph nodes or other nearby structures is known as regional. About 19 percent of females are diagnosed with regional endometrial cancer, per SEER, and the five-year survival for regional endometrial cancer is almost 70 percent.

Cancer that has metastasized is referred to as distant. The five-year survival rate for distant endometrial cancer is about 18 percent.

Other factors, such as your age and overall health, can also influence your prognosis. Additionally, advances in cancer research have developed new treatments for endometrial cancer that may provide better outcomes than the numbers above show. These statistics are based on females who were diagnosed and treated between 2013 and 2019.

Talk With Others Who Understand

MyEndometrialCancerCenter is the social network for people with endometrial cancer and their loved ones. On MyEndometrialCancerCenter, members come together to ask questions, give advice, and share their stories with others who understand life with endometrial cancer.

Do you still have questions about endometrial cancer staging? Share in the comments below, or start a conversation by posting on your Activities page.