Ovarian Cancer Stages
A cancer’s stage explains how large the primary tumor is and how far the cancer has spread in the patient’s body. Doctors use the information to understand the disease and develop a treatment plan.
There are several different staging systems. Many of these have been created for specific kinds of cancers. Others can be used to describe several types of cancer.
The stages of ovarian cancer are set by FIGO, the International Federation of Gynecology and Obstetrics. They range from stage I to stage IV. Higher numbers mean the cancer is more advanced and generally harder to treat.
Ovarian tube cancer stages
(Source: National Cancer Institute)
Fallopian tube cancer, ovarian cancer and primary peritoneal cancer are related diseases and share one set of stages.
Stage I ovarian cancer
In stage I, cancer is found in one or both ovaries or fallopian tubes. Stage I is divided into stage IA, stage IB, and stage IC.
Stage IA: Cancer is found inside a single ovary or fallopian tube.
Stage IB: Cancer is found inside both ovaries or fallopian tubes.
Stage IC: Cancer is found inside one or both ovaries or fallopian tubes and one of the following is true:
- the tumor ruptured (broke open) during surgery; or
- the capsule (outer covering) of the ovary ruptured before surgery, or there is cancer on the surface of the ovary or fallopian tube; or
- cancer cells are found in the fluid of the peritoneal cavity (the body cavity that contains most of the organs in the abdomen) or in washings of the peritoneum (tissue lining the peritoneal cavity).
Stage II ovarian cancer
In stage II, cancer is found in one or both ovaries or fallopian tubes and has spread into other areas of the pelvis, or primary peritoneal cancer is found within the pelvis. Stage II is divided into stage IIA and stage IIB.
Stage IIA: Cancer has spread from where it first formed to the uterus and/or the fallopian tubes and/or the ovaries.
Stage IIB: Cancer has spread from the ovary or fallopian tube to organs in the peritoneal cavity (the body cavity that contains most of the organs in the abdomen).
Stage III ovarian cancer
In stage III, cancer is found in one or both ovaries or fallopian tubes, or is primary peritoneal cancer, and has spread outside the pelvis to other parts of the abdomen and/or to nearby lymph nodes. Stage III is divided into stage IIIA, stage IIIB, and stage IIIC.
Stage IIIA: One of the following is true:
Cancer has spread to lymph nodes behind the peritoneum only; or
Cancer cells that can be seen only with a microscope have spread to the surface of the peritoneum outside the pelvis, such as the omentum (a fold of the peritoneum that surrounds the stomach and other organs in the abdomen). Cancer may have spread to nearby lymph nodes.
Stage IIIB: Cancer has spread to the peritoneum outside the pelvis, such as the omentum, and the cancer in the peritoneum is 2 centimeters or smaller. Cancer may have spread to lymph nodes behind the peritoneum.
Stage IIIC: Cancer has spread to the peritoneum outside the pelvis, such as the omentum, and the cancer in the peritoneum is larger than 2 centimeters. Cancer may have spread to lymph nodes behind the peritoneum or to the surface of the liver or spleen.
Stage IV ovarian cancer
In stage IV, cancer has spread beyond the abdomen to other parts of the body. Stage IV is divided into stage IVA and stage IVB.
Stage IVA: Cancer cells are found in extra fluid that builds up around the lungs.
Stage IVB: Cancer has spread to organs and tissues outside the abdomen, including lymph nodes in the groin.