The 4 Stages of Ovarian Cancer, Explained

If you’re diagnosed with ovarian cancer, doctors will assign the cancer one of four “stages.” These categories are based on how far the cancer has spread. Stage 1 means the tumor has not spread beyond the ovary. Stage 4 is the most advanced and signifies that the cancer has spread around the body. Each stage also has subcategories.

Ovarian cancer staging is determined by three things: the size of the tumor; whether the cancer has spread to the lymph nodes; and whether the cancer cells have metastasized to organs that are farther away (like the liver) or to the fluid around the lungs.

Staging is one of the first steps in figuring out how to deal with cancer. “Staging determines further treatment and it determines prognosis,” says Otis Brawley, MD, chief medical officer of the American Cancer Society. “Usually clinical stages 1, 2, and 3 are going to get some type of surgery with the intention to try to cure. Stage 4 is not going to get surgery unless it’s for purposes of palliation.”

Everyone is different and every cancer is different. The stage of your ovarian cancer at the time you’re diagnosed doesn’t seal your fate. But it does give you valuable information to help navigate the days ahead.

Here are the four stages of ovarian cancer and the typical treatments for each.

Stage 1 ovarian cancer

Stage 1 tumors are confined to the ovaries or fallopian tubes and have not spread at all.

This type of tumor is the easiest to treat, even cure. Overall, women who are diagnosed with stage 1 ovarian cancer have a 90% chance of still being alive five years later. Many will also live many years beyond that.

There are subtypes of stage 1 ovarian cancer. Stage 1A means the cancer is only in one ovary or fallopian tube. “This is an important stage because the tumor is basically confined to one ovary and not growing into anything else and it can be removed completely intact,” says David Kushner, MD, professor of gynecologic oncology at the University of Wisconsin School of Medicine and Public Health. In some cases, women with stage 1A ovarian cancer can skip chemo.

Stage 1B is when the cancer has reached both ovaries or fallopian tubes but no farther. Stage 1C means the cancer is still on the inside of both ovaries or fallopian tubes and has also broken through the surface of the ovary to reach the outside. This could happen before surgery or during surgery (called intraoperative surgical spill). Ovarian cancer cells may also be found in the fluid in the abdomen.

Stage 2 ovarian cancer

In stage 2 ovarian cancer, the tumor is still in the ovaries and fallopian tubes but has also started spreading to nearby organs in the pelvis.

“Stage 2 means that the tumor has actually come in contact with and spread to other organs nearby,” says Dr. Brawley. ”This could be the uterus or fallopian tubes, in the case of 2A. Stage 2B means that it has grown into other nearby organs like the colon, bladder, or rectum.”

Overall, the five-year survival rate for this stage is 70%. Treatment usually consists of surgery and chemotherapy.

Stage 3 ovarian cancer

By stage 3, an ovarian cancer tumor is still in one or both ovaries or fallopian tubes but has started to spread even farther. Stage 3A is divided into two categories. In Stage 3A1, the cancer is still in one or both ovaries and is found in the lymph nodes. In Stage 3A2, the cancer may or may not be in the lymph nodes, but microscopic cells have spread to the abdominal cavity.

Stage 3B means the tumor is in one or both ovaries or fallopian tubes and outside the pelvis. The doctor can actually see the cancer that is in the abdomen now, but it’s still no bigger than 2 centimeters in diameter. It may or may not be in the lymph nodes.

By Stage 3C, the cancer has spread from the pelvis to the abdomen and is bigger than 2 centimeters. It may even have reached the surface of more distant organs like the liver or spleen. Again, the lymph nodes may or may not be affected.

This type of ovarian cancer is treated much the same as stage 2 cancer, with surgery to remove the affected organs then chemo and perhaps more surgery. The overall five-year survival for stage 3 ovarian cancer drops to 39%.

Stage 4 ovarian cancer

Stage 4 is the most advanced stage of ovarian cancer. Here, the cancer has metastasized far beyond the ovaries and/or fallopian tubes. In stage 4A, cancer cells are found in the fluid around the lungs. In 4B, they’ve moved even farther to the inside of the spleen, liver, lungs, brain, or other organs far away from the original tumor, as well as to lymph nodes located in the groin.

When the cancer is this advanced, says Dr. Brawley, doctors stop trying to cure it. Treatment–including chemotherapy, surgery, and other palliative procedures–is focused on making the patient comfortable. The five-year survival rate for stage 4 ovarian cancer is 17%.