Understanding the Ovarian Cancer FIGO Surgical Staging System

How Can Doctors Determine the Stage and Substage of Your Cancer?

A doctor discusses a report with a patient.
A doctor discusses a report with a patient. Eric Audras/Getty Images

The full FIGO -- International Federation of Gynecology and Obstetrics -- ovarian cancer surgical staging system is based on Roman numerals as well as letters to designate sub-stages. In general, prognosis depends more upon the main Stage. However, the sub-stages can also be important in helping you and your doctor choose the best treatments. Read more in the Treatment Options topic on this site.

Stage I

In stage I ovarian cancer, the cancer is limited to the ovaries. This is broken down into:

IA - The cancer is limited to one ovary and the outer ovarian capsule is not ruptured. There is no tumor on the external surface of the ovary and there is no ascites and/or the washings are negative.

  • Ascites refers to extra fluid in the abdomen that can occur with ovarian cancer.
  • The term "washings" refers to a procedure surgeons do during ovarian cancer surgery in which they inject fluid into the abdomen, draw it back out, and then a pathologist looks at the sample for evidence of any cancer cells.

IB - The cancer is present in both ovaries, but the outer capsule is intact and there is no tumor on external surface. There is no ascites and the washings are negative.

IC - The cancer is either Stage IA or IB level but the capsule is ruptured, there is a tumor on the ovarian surface, or malignant cells are present in ascites or washings.

Stage II

Ovarian cancer is stage 2 when it involves one or both ovaries along with spread to other pelvic organs or surfaces.

IIA - The cancer has extended onto the uterus and/or fallopian tube. The washings are negative washings and there is no ascites.

IIB - The cancer has extended onto other pelvic tissues beyond the uterus and fallopian tube.

The washings are negative and there is no ascites.

IIC - The cancer has extended to pelvic tissues like Stage IIA or IIB, but with positive pelvic washings.

Stage III

In stage III ovarian cancer, the cancer has spread outside of the pelvis into the abdominal area or the surface of the liver.

IIIA - Tumor is grossly (the term grossly means that it can be seen with the naked eye) confined to the pelvis but with microsopic peritoneal metastases (spread seen only under the microscope) beyond the pelvis to abdominal peritoneal surfaces or the omentum. The omentum is the fatty structure that drapes over the intestines and other abdominal organs.

IIIB - This stage is similar to stage IIIA but with macroscopic spread (spread that can be seen visually) to the peritoneum or omentum. At this stage, the areas of cancer that have spread are less than 2 cm (a little less than an inch) in size.

IIIC - This stage is also similar to stage IIIA but with peritoneal or omental metastases (spread) beyond the pelvis with areas larger than 2 cm (an inch) in size, or with spread to lymph nodes in the groin (inguinal nodes), pelvis (pelvic nodes) or para-aortic (para-arotic nodes.)

Stage IV

In stage IV ovarian cancer, the cancer has spread to the body of the liver, or to areas outside of the lower abdomen (the peritoneal cavity) to areas such as the chest or brain.

When You are Diagnosed

Being diagnosed with ovarian cancer can be terrifying. In addition to living with symptoms and a scary diagnosis, you may feel like you're learning a foreign language. Learn to ask the right questions about ovarian cancer. Consider joining a support group in your community, or an online ovarian cancer community. Let others help you. Cancer treatment is improving every year, even for people with advanced stage cancers.


American Society of Clinical Oncology. Ovarian, Fallopian Tube, and Peritoneal Cancer: Stages and Grades. Cancer.Net. http://www.cancer.net/cancer-types/ovarian-fallopian-tube-and-peritoneal-cancer/stages-and-grades.

American Cancer Society. How Is Ovarian Cancer Staged? https://www.cancer.org/cancer/ovarian-cancer/detection-diagnosis-staging/staging.html.