Ovarian cancer, like many other cancers, is heterogenous. However, it can be mainly divided into three groups, based on the cell type the tumours originate from: epithelial, germ cell, or sex-cord stromal. Epithelial ovarian cancer originates from the cells that line the ovaries, accounts for the majority (90%) of ovarian cancer, and occurs more commonly in women between the ages of 40-60. Germ cell ovarian cancer is rare (5%) and originates from the cells that give rise to the egg cells, or ova, located in the ovaries. This cancer usually affects younger women in their 20s. Sex-cord stromal ovarian cancer is also rare (5%); it originates from the cells that make the connective tissue of the ovary and produce female hormones.
Regardless of the type, there are four stages of ovarian cancer: stage I (early disease) to stage IV (advanced disease). Once a woman is diagnosed with cancer, the stage of the cancer is usually determined after surgery. The treatment plan and and prognosis (disease outcome) is determined by the stage of cancer.
- Ovarian Cancer. Cancer Research UK, 14 Dec. 2018, www.cancerresearchuk.org/about-cancer/ovarian-cancer/