Definition

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 stages IIIA, IIIB, and IIIC. In stage IIIA, one of the following is true: (1) cancer has spread to lymph nodes behind the peritoneum (tissue that lines the abdominal wall and covers organs in the abdomen) only; or (2) 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. In 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. In 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.