Causes

It's not clear what causes ovarian cancer, though doctors have identified things that can increase the risk of the disease.

Doctors know that ovarian cancer begins when cells in or near the ovaries develop changes (mutations) in their DNA. A cell's DNA contains the instructions that tell the cell what to do. The changes tell the cells to grow and multiply quickly, creating a mass (tumor) of cancer cells. The cancer cells continue living when healthy cells would die. They can invade nearby tissues and break off from an initial tumor to spread (metastasize) to other parts of the body.

Types of ovarian cancer

The type of cell where the cancer begins determines the type of ovarian cancer you have and helps your doctor determine which treatments are best for you. Ovarian cancer types include:

• Epithelial ovarian cancer. This type is the most common. It includes several subtypes, including serous carcinoma and mucinous carcinoma.
• Stromal tumors. These rare tumors are usually diagnosed at an earlier stage than other ovarian cancers.
• Germ cell tumors. These rare ovarian cancers tend to occur at a younger age.