Undetected, these malignant cells can spread to other organs and tissues throughout her pelvis and abdomen. Epithelial ovarian cancer is the growth of malignant cells in the covering of the ovary. It accounts for 85 percent to 90 percent of all women diagnosed and generally occurs sometime after age 50. About half of all ovarian cancers occur after age 65. The ovaries are small reproductive organs located on either side of the uterus and deep inside the pelvis.
Ovaries make female hormones and grow eggs inside tiny follicles.
When an egg is mature, the follicle ruptures, the egg breaks through the covering of the ovary, is released into the fallopian tube and heads toward the uterus. If sperm fertilizes it, the fertilized egg makes its way to the uterus, attaches to the uterine lining and grows into a baby. New cells grow to replace the damaged ones. Occasionally, an abnormal cell is generated and that cell can eventually become a malignant cancer cell. Researchers, however, still aren't sure what triggers the growth of these abnormal cells.