There are several types of ovarian cancer that a woman can be diagnosed with, but one form accounts for nearly all diagnoses of the disease. According to the American Cancer Society, 90 percent of women diagnosed with ovarian cancer have what’s known as a malignant epithelial ovarian tumor. This type of ovarian cancer tumor has individual characteristics which can be spotted under microscopic examination.

There is also a grading system in place for this type of ovarian cancer, which indicates the severity and outlook for a specific incidence. A grade of 1 means the cancerous cells look fairly normal under a microscope, while grade 3 means there is a significant difference in appearance between the tumor’s cells and normal cells.

According to National Cancer Institute statistics, from 2002 to 2006, approximately 62 percent of all ovarian cancers were diagnosed late, after the disease has spread to distant areas of the body. However, it is important to remember that although ovarian cancer can be deadly, the disease accounts for only 5 percent of all cancers in women.