Stages, Grades and Types

Stages of ovarian cancer are classified as Roman numerals I-IV (1-4). The higher the number, the more the disease has spread:
  • Stage I: The cancer is confined to one or both ovaries.
  • Stage II: Ovarian cancer has spread to another area within the pelvis without spreading elsewhere in the abdomen.
  • Stage III: Cancer has spread from one or both ovaries to the lining of the abdomen or lymph nodes.
  • Stage IV: Ovarian cancer has spread beyond the abdomen to distant organs, such as the lung or liver.

What is recurrence?
The American Cancer Society defines cancer recurrence as the return of cancer after treatment and after a period of time during which the cancer cannot be detected. The cancer may come back in the same area that it was first detected or another area of the body.

There are also three grades of ovarian cancer:

  • Grade 1 is “well-differentiated”
  • Grade 2 is “moderately differentiated”
  • Grade 3 is “poorly differentiated”

The lower the grade, the slower the cancer cells grow.

There are several different tumor types in ovarian cancer:

  • Epithelial tumors – About 90 percent of ovarian cancers develop in the epithelium, the thin layer of tissue that covers the ovaries and makes up the fallopian tubes. This form of ovarian cancer generally occurs in postmenopausal women.
  • Germ cell carcinoma tumors – Making up about five percent of ovarian cancer cases, this type begins in the cells that form eggs. While germ cell carcinoma can occur in women of any age, it tends to be found most often in women in their early 20s. Six main kinds of germ cell carcinoma exist, but the three most common types are: teratomas, dysgerminomas, and endodermal sinus tumors. Many tumors that arise in the germ cells are benign.
  • Stromal carcinoma tumors – Ovarian stromal carcinoma accounts for about five percent of ovarian cancer cases. It develops in the connective tissue cells that hold the ovary together and those that produce the female hormones estrogen and progesterone. The two most common types are granulosa cell tumors and sertoli-leydig cell tumors. Unlike with epithelial ovarian carcinoma, 70 percent of stromal carcinoma cases are diagnosed in Stage I.
  • Small cell carcinoma of the ovary – Small Cell Carcinoma of the Ovary (SCCO) is a rare, highly malignant tumor that affects mainly young women, with a median age at diagnosis of 24 years old. The subtypes of SCCO include pulmonary, neuro-endocrine and hypercalcemic. SCCO accounts for 0.1% of ovarian cancer cases. Approximately two-thirds of patients with SCCO have hypercalcemia. The symptoms are the same as other types of ovarian cancer.

For a more detailed look at the staging for ovarian cancer, visit FIGO Ovarian Cancer Staging. This new staging was revised and approved for ovarian cancer in January 2014 by the International Federation of Gynecologists and Obstetricians (FIGO).

Updated May 28, 2015