Ovarian Cancer Stages

Ovarian cancer stages are used to describe the spread and aggressiveness of a tumor. Staging occurs after a diagnosis of ovarian cancer is made. The stage and grade of a tumor are important prognostic factors that help determine the outcome of the cancer and treatment options.

Surgical Cancer Staging and Laparotomy

Cancer staging requires a surgical technique called a laparotomy. During a laparotomy a surgical incision is made in the abdomen so the surgeon can visually examine the ovaries, the pelvic cavity and the abdomen. The surgeon removes as much of the tumor as possible, along with any lymph nodes that may be affected. If possible, a qualified gynecologic oncologist should perform the laparotomy.

A number of imaging techniques may be used to help stage the cancer, including x-rays, ultrasound and CT scans. A CT scan, or CAT scan, uses x-rays to produce multiple cross section images or “slices” of the body.

Ovarian Cancer Stages

Cancer of the ovaries goes through four stages.

  • Stage I tumors are confined to one or both of the ovaries. The disease has not spread to other organs.
  • Stage II tumors have spread from the ovaries into the pelvic region.
  • Stage III cancers have spread through the pelvic cavity to the lymph nodes, the small bowel or the surface of the liver. Unfortunately, few cases of ovarian cancer are diagnosed before Stage III.
  • Stage IV cancers have metastasized to distant organs which can include the lungs.

At a Glance: Ovarian Cancer Stages

  • Stage I: Limited to ovary; 90 percent survival.
  • Stage II: Limited to pelvic region; 70 percent survival.
  • Stage III: Spread throughout abdomen; 15 to 20 percent survival.
  • Stage IV: Spread beyond abdomen, metastasis; 1 to 5 percent survival.

Histopathology: Grading Tumors

Histopathology is the evaluation of cancerous cells at a microscopic level, and is the basis for tumor grading. Histopathology grades tumors depending on the level of differentiation, or maturity, of the cells. Well-differentiated cells look very much like healthy, mature cells, and are likely to be less aggressive than tumor cells that resemble immature cells. Histopathology assigns the tumor cells one of three grades:

  • Grade one: The tumor cells closely resemble healthy cells, indicating a low malignancy potential and slow rate of metastasis.
  • Grade two: The tumor cells resemble healthy cells, but are not as well differentiated as Grade one cells.
  • Grade three: The tumor cells are arrested at immature stages of development, and have abnormal shapes.

Prognosis Factors

The most accurate ovarian cancer prognosis depends on staging and grading scores. However, a few other factors come into play. Older women have a worse prognosis, as do women who have ascites (fluid retention in the abdomen). The amount of cancerous tissue remaining after the laparotomy may also have a positive or negative affect on prognosis.


Armstrong, D. (2002). Relapsed ovarian cancer: challenges and management strategies for a chronic disease. The Oncologist7 (suppl. 5), 20-28.