What are Ovarian Tumors

Ovarian tumors form in the ovaries, which are the organs of the female reproductive system. The ovaries perform important reproductive functions including egg production and hormone production. There are three types of cells that make up the ovary, the epithelial cells, the germ cells and the stromal cells.

Ovarian cancer can occur in all of these cell areas of the ovary. Epithelial cells cover the ovary. Germ cells are inside the ovary and are where the cells develop into the eggs that are released into the fallopian tubes every month. Stromal cells are utilized to produce the female hormones estrogen and progesterone.

3 Tumor Types

The three types of ovarian tumors correspond to the three types of ovarian cells just discussed. There are epithelial tumors, germ cell tumors, and stromal tumors. Most of the ovarian tumors up to 95% are epithelial cell tumors.

Most of these epithelial ovarian tumors are benign and to do spread, and do not lead to serious illnesses. There are three types of epithelial ovarian tumors: serous adenomas, mucinous adenomas, and also Brenner tumors.


The epithelial tumors that are cancerous are called epithelial ovarian carcinomas. The serous type is the most common type of epithelial ovarian tumor. The other types are called mucinous, endometrioid, and also clear cell.

Undifferentiated epithelial ovarian carcinomas cells do not look like any of the 4 subtypes mentioned above. They grow very fast and spread more quickly than the other subtypes. Tumors are graded on a scale of 1, 2, or 3.

Germ Cell

Germ cell tumors form the ova (eggs) and most of the tumors that form here are benign. Approximately 5% of ovarian cancers are germ cell tumors. There are subtypes of germ cell tumors called teratoma, dysgerminoma, endodermal sinus tumor, and choriocarcinoma.


Stromal tumors account for 5% to 7% of ovarian cancers with most of these being granulosa cell tumors. Most of these stromal tumors are found in women over age 50 with 5% of them being in younger women. The most common symptom experienced by women with these tumors is abnormal vaginal bleeding.

There are subtypes of stromal tumors called granulosa cell tumors, granulosa-theca tumors, and Sertoli-Leydig cell tumors. These tumors are low-grade cancers. Thecomas and fibromas are both benign stromal tumors.


Removing the ovary or part of the ovary treats benign ovarian tumors. Malignant (cancerous) Ovarian tumors can spread to other parts of the body and are more complicated to treat.

Treatment for ovarian tumors will depend on if the cancer has spread beyond the ovaries, the general health and age of the woman, and also the stage of the cancer.

The first thing the doctor will do is “stage” the cancer which means that the doctor will determine how far the cancer has spread from the ovary if at all.

When the omentum is removed (fatty tissue covering the abdominal contents the surgery is called an omentectomy.

A major abdominal operation for ovarian cancer that examines all tissue and organs in the pelvic cavity in order to determine disease stage is called laparotomy.

A hysterectomy for ovarian cancer is when the uterus is removed as a treatment for the cancer.

A salpingo-oophorectomy is a surgical procedure to remove the ovaries and fallopian tubes.

The surgeries connected with ovarian cancer are performed to diagnose, stage and treat cancer.