“The ovaries are the main source of the female hormones, estrogen and progesterone.

The ovaries are mainly made up of 3 kinds of cells. Each type can develop into a different type of tumor:

• Epithelial tumors start from epithelial cells that line the fallopian tubes and ovaries. Most ovarian tumors are epithelial cell tumors.
• Germ cell tumors start from the cells that produce the eggs (ova).
• Stromal tumors start from structural tissue cells that hold the ovary together and produce the female hormones, estrogen and progesterone.

Some of these tumors are benign (non-cancerous) and do not spread beyond the ovary. Malignant (cancerous) or borderline (low malignant potential) ovarian tumors can spread (metastasize) to other parts of the body and can be fatal.”

American Cancer Society (Ovarian Cancer | American Cancer Society)