Ovarian epithelial cancer is a disease in which malignant cells form in the tissue covering the ovary. This is one type of cancer that affects the ovary. Women who have a family history of ovarian cancer are at an increased risk of developing ovarian cancer.
Ovarian cancer is hard to detect (find) early because usually there are no symptoms. Some women who have early stage ovarian cancer may have symptoms such as vague gastrointestinal (GI) discomfort, pressure in the pelvis, pain, swelling of the abdomen, and shortness of breath. Most of the time, there are no symptoms or they are very mild. By the time symptoms do appear, the cancer is usually advanced.
When found in its early stages, ovarian epithelial cancer can be cured in many patients.
Patients with ovarian cancer are treated at our Gynecologic Cancer Unit. You can also review the tabs at top of this page for information on ovarian cancer symptoms and risks, diagnosis, and treatment.
The ovary contains three types of tissue, and each type can develop a unique kind of cancer.
Epithelial ovarian cancer
Epithelial ovarian cancer, the most common form of ovarian cancer, begins in the cells covering the ovaries. These tumors can be classified as:
- Benign, or non-cancerous; these usually do not lead to serious illness.
- Tumors of low malignant potential, which are are also known as borderline epithelial ovarian cancer, have precancerous cells that may become cancerous.
- Malignant epithelial ovarian tumors, which are called carcinomas. These tumors are categorized into subtypes according to cell features which can be seen under a microscope. Subtypes include serous (the most common), mucinous, endometrioid and clear cell. Tumors that don't fit into any of these subtypes are known as undifferentiated. Undifferentiated tumors tend to grow and spread more quickly than the other types.
Primary Peritoneal Carcinoma (PPC)
PPC is a rare cancer closely related to epithelial ovarian cancer. Other names for this cancer include extra-ovarian (meaning outside the ovary) primary peritoneal carcinoma (EOPPC), or serous surface papillary carcinoma. PPC develops in cells from the lining of the pelvis and abdomen (the peritoneum), which are very similar to cells on the surface of the ovaries.
Germ cell tumors
Ovarian germ cell tumors develop from the cells that produce the ova, or eggs, within the ovary. Most germ cell tumors are benign but about 5% are cancerous; these are most frequently seen in teenage girls or young women. Types of germ cell tumors include:
- Dysgerminoma: A rare type of cancer, but the most common ovarian cancer of germ cells. Although considered malignant, most do not grow or spread rapidly and most patients are cured by surgical removal of the ovary.
- Teratomas: These look like three layers of a developing embryo when seen under a microscope. A form of this tumor, called a mature teratoma, is benign and is the most common type of benign germ cell tumor. Another form, called an immature teratoma, is cancerous and usually affects girls and women younger than age 18. Grade 1 immature teratoma that have not spread beyond the ovary are generally cured by surgical removal of the ovary, followed by continued observation. More advanced stages can require chemotherapy in addition to surgery, depending on the stage and the individual patient.
- Endodermal sinus tumors and choriocarcinoma: Both are very rare and typically affect girls and young women. They tend to grow and spread rapidly but are sensitive to chemotherapy.
About 5% to 7% of ovarian cancers are stromal tumors, which begin in the connective tissue cells of the ovary. More than half are found in women older than 50, but about 5% of stromal tumors occur in young girls. Types of malignant stromal tumors include granulosa cell tumors (which account for the majority of stromal tumors), granulosa-theca tumors, and Sertoli-Leydig cell tumors (which are usually considered low-grade cancers). Thecomas and fibromas are non-malignant stromal tumors.
An ovarian cyst is a collection of fluid inside an ovary that will usually disappear after a few months. Your doctor may order tests to learn more about your cyst if you aren’t ovulating, if the cyst is large, or if it doesn’t go away on its own. A small number of ovarian cysts turn out to be malignant; surgery may be needed to diagnose these.
Following a physical exam and medical history, your doctor will order blood tests to assess your red and white blood cells, as well as the amount of hemoglobin, the protein that carries oxygen, in the red blood cells. Bone marrow aspiration and biopsy may also be performed. Using this information, your physician will be able to determine the type and stage of MDS.
The stages of myelodysplastic syndromes are:
- De novo myelodysplastic syndromes, which develop without any known cause
- Secondary myelodysplastic syndromes, which can develop after you’ve been treated with chemotherapy and radiation therapy for other diseases or after being exposed to radiation or certain chemicals
- Previously treated myelodysplastic syndromes, which are MDS that have been treated but have not responded
- Enlargement of the abdomen, which is caused by accumulation of fluid
- In women over 40, vague digestive disturbances (stomach discomfort, gas, distention) that persist and cannot be explained by any other cause
- Feeling the need to urinate often
- Pressure or pain in the abdomen, pelvis, back, or legs
- Feeling very tired all the time
- Shortness of breath
- Unusual vaginal bleeding (heavy periods, or bleeding after menopause)
- Age (peaks in the eighth decade)
- Women who have never had children
- Women who have had breast cancer or have a family history of breast or ovarian cancer
- Inherited genetic mutations in the BRCA1 or BRCA2 genes
- Hereditary non-polyposis colon cancer (HNPCC) or Lynch Syndrome
- Obesity: Excess body fat as measured by BMI (body mass index), including during the teen years
- Hormone replacement therapy, also called hormone therapy (risk may be different for estrogen-only therapy and estrogen-progestin replacement therapy)
- Use of fertility drugs
- Use of talcum powder
Possible protective factors
Protective factors which may decrease risk of ovarian cancer, according to the PDQ® database, include:
- Use of oral contraceptives: Compared with women who have never used them, women who have used them for three or more years may reduce their risk by up to 50 percent.
- Childbearing and breastfeeding: Having at least one child has been shown to lower risk, while breastfeeding for a year or longer may reduce your risk.
- Tubal ligation: This sterilization procedure has been linked to lower risk.
If you have a symptom that suggests ovarian cancer, your doctor needs to determine whether it is due to cancer or some other cause. For example, you may have an ovarian cyst, a borderline tumor (also known as a tumor of low malignant potential), an adnexal mass, or endometriosis.
You may have one or more of the following tests and examinations:
- A physical exam: Including a pelvic exam to feel the ovaries and nearby organs for lumps or other changes in their shape or size, and an abdominal exam to check the area for tumors or an abnormal buildup of fluid (ascites).
- A detailed family and medical history: If you have a history of ovarian or breast cancer in your family, you may want to consider genetic counseling to determine if you are carrying mutations of the BRCA1 or BRCA2 gene, both of which are associated with inherited ovarian and breast cancer.
- Blood tests: These may include a test for CA-125 (cancer antigen-125), which is a protein found at elevated levels in most ovarian cancer cells compared to normal cells. High levels of CA-125 can indicate cancer or other conditions, but the CA-125 test is not used alone to diagnose ovarian cancer. Ideally, it should be used as a series of tests over time and combined with other diagnostic tests.
- Ultrasound: Uses high-frequency sound waves to create images of the internal organs. A device known as a transducer is used to produce and receive the sound waves, which are then translated via computer into images. These images provide a view of the ovaries and any abnormalities that may exist. The transducer is generally inserted into the vagina (transvaginal ultrasound).
- Surgery: Based on the results of the blood tests and ultrasound, your doctor may suggest surgery (a laparotomy) to remove tissue and fluid from the pelvis and abdomen. Surgery is usually needed to diagnose ovarian cancer.
- Laparoscopy: Although most women have a laparotomy for diagnosis, some women have a less-invasive procedure known as laparoscopy. The doctor inserts a thin, lighted tube (a laparoscope) through a small incision in the abdomen to examine the ovary. However, most physicians agree that a laparotomy provides a superior means of diagnosis. A laparoscopy may be used to remove a small, benign cyst, but maligant tumors are commonly removed via laparotomy.
Ovarian cancer stages are used to describe the size of a tumor, whether it has spread beyond the ovary, and, if so, to what extent. Staging is done using results of a surgical biopsy and can also involve results from other tests, such as imaging or blood tests. The information gathered from the staging process determines the stage and grade of the disease, which is vital for determining the best course of treatment.
According to the National Cancer Institute, the stages of ovarian cancer are:
- Stage I: Cancer cells are found in one or both ovaries. Cancer cells may be found on the surface of the ovaries or in fluid collected from the abdomen.
- Stage II: Cancer cells have spread from one or both ovaries to other tissues in the pelvis. Cancer cells are found on the fallopian tubes, the uterus, or other tissues in the pelvis. Cancer cells may be found in fluid collected from the abdomen.
- Stage III: Cancer cells have spread to tissues outside the pelvis or to the regional lymph nodes. Cancer cells may be found on the outside of the liver.
- Stage IV: Cancer cells have spread to tissues outside the abdomen and pelvis. Cancer cells may be found inside the liver, in the lungs, or in other organs.
Grading refers to the appearance of the cancer cells when they are looked at under the microscope as compared to normal cells. The grade gives an idea of how quickly the cancer may develop.
- Grade 1 (low-grade) means the cancer cells look very similar to normal cells of the ovary. These generally grow slowly and are less likely to spread than higher grades.
- Grade 2 (moderate-grade) means the cells look more abnormal than Grade 1 cells.
- Grade-3 (high-grade) means the cells look very abnormal. These are the most likely to grow quickly and spread.
Your doctor may also order additional tests to find out whether the cancer has spread. These may include a computed tomography (CT) scan, a magnetic resonance imaging (MRI), a chest X-ray and/or a lower GI series of X-rays of the colon and rectum, or a colonoscopy to determine if the cancer has spread to the rectum or colon.