Stages of Ovarian Epithelial, Fallopian Tube, and Primary Peritoneal Cancer

After ovarian, fallopian tube, or peritoneal cancer has been diagnosed, tests are done to find out if cancer cells have spread within the ovaries or to other parts of the body.

The process used to find out whether cancer has spread within the organ or to other parts of the body is called staging. The information gathered from the staging process determines the stage of the disease. It is important to know the stage in order to plan treatment. The results of the tests used to diagnose cancer are often also used to stage the disease. (See the General Information section for tests and procedures used to diagnose and stage ovarian, fallopian tube, and peritoneal cancer.)

There are three ways that cancer spreads in the body.

Cancer can spread through tissue, the lymph system, and the blood:

• Tissue. The cancer spreads from where it began by growing into nearby areas.
• Lymph system. The cancer spreads from where it began by getting into the lymph system. The cancer travels through the lymph vessels to other parts of the body.
• Blood. The cancer spreads from where it began by getting into the blood. The cancer travels through the blood vessels to other parts of the body.

Cancer may spread from where it began to other parts of the body.

When cancer spreads to another part of the body, it is called metastasis. Cancer cells break away from where they began (the primary tumor) and travel through the lymph system or blood.

• Lymph system. The cancer gets into the lymph system, travels through the lymph vessels, and forms a tumor (metastatic tumor) in another part of the body.
• Blood. The cancer gets into the blood, travels through the blood vessels, and forms a tumor (metastatic tumor) in another part of the body.

The metastatic tumor is the same type of cancer as the primary tumor. For example, if ovarian epithelial cancer spreads to the lung, the cancer cells in the lung are actually ovarian epithelial cancer cells. The disease is metastatic ovarian epithelial cancer, not lung cancer.

The following stages are used for ovarian epithelial, fallopian tube, and primary peritoneal cancer:

Stage I

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

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

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.

• In 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

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.

Ovarian epithelial, fallopian tube, and primary peritoneal cancers are grouped for treatment as early or advanced cancer.

Stage I ovarian epithelial and fallopian tube cancers are treated as early cancers.

Stages II, III, and IV ovarian epithelial, fallopian tube, and primary peritoneal cancers are treated as advanced cancers.

Ovarian epithelial, fallopian tube, and primary peritoneal cancers can recur (come back) after treatment.

The cancer may come back in the same place or in other parts of the body. Persistent cancer is cancer that does not go away with treatment.