Ovarian Cancer: NCCN Guidelines for Patients
December 24, 2022 - read ≈ 16 min
The NCCN Guidelines for Patients were developed by the National Comprehensive Cancer Network (NCCN). NCCN is an organization that unites leading cancer care centers in the United States of America. Its activities are focused on scientific research, treatment and education of patients.
Ovarian cancer basics
Most ovarian cancers start in the layer of tissue surrounding the ovaries, called the epithelium. The information in this patient guide applies to the most common types of epithelial ovarian cancer.
The ovaries are a pair of organs in the female reproductive system.
The reproductive system is the group of organs that work together for the purpose of sexual reproduction. In addition to the ovaries, this system includes the fallopian tubes, uterus, cervix, and vagina.
Each ovary is about the size and shape of a grape. The ovaries are located in the pelvis. The pelvis is the area below the belly (abdomen) and between the hip bones. One ovary is on the left side of the uterus and one is on the right. Each ovary is connected to the uterus by a long, thin tube called a fallopian tube.
The ovaries make eggs for sexual reproduction. They also make hormones that affect breast growth, body shape, and the menstrual cycle. Eggs pass out of the ovary and travel through the attached fallopian tube into the uterus.
The uterus is where an unborn baby grows and develops during pregnancy. It is also called the womb. The uterus and at least one ovary are needed for menstruation and pregnancy.
Types of ovarian cancer
The most common type of ovarian cancer is epithelial ovarian cancer. It starts in the layer of tissue surrounding the ovaries (the epithelium). There are more than 5 different subtypes of epithelial ovarian cancer. Some are more common than others. The information in this patient guide applies to the most common forms of epithelial ovarian cancer, listed below:
- High-grade serous carcinoma
- High-grade endometrioid carcinoma
Less common ovarian cancers
Rare types of ovarian cancer are called less common ovarian cancers (LCOCs) or less common ovarian histologies (LCOHs). These less common types are listed below. Treatment of these ovarian cancers is addressed in the comprehensive NCCN Clinical Practice Guidelines in Oncology for Ovarian Cancer, but is beyond the scope of this guide.
Less common epithelial ovarian cancers:
- Low-grade serous carcinoma
- Low-grade endometrioid carcinoma
- Carcinosarcoma (malignant mixed Mullerian tumors [MMMTs] of the ovary)
- Clear cell carcinoma
- Mucinous carcinoma
- Low malignant potential (LMP) tumors (also called borderline epithelial tumors)
Less common non-epithelial ovarian cancers:
- Malignant sex-cord stromal tumors
- Malignant germ cell tumors
How is the type determined?
As discussed later in this guide, surgery is the recommended first treatment for most ovarian cancers when possible. The tumor and other tissue removed during surgery are sent to an expert in testing cells to find disease, called a pathologist. The pathologist determines the type of ovarian cancer by examining the cancerous tissue.
The pathologist also determines the cancer grade. This is different than the cancer stage.
The cancer grade is a rating of how fast the cancer is expected to grow and spread. It is based on how abnormal the cancer cells look under a microscope. High-grade cancers grow and spread more quickly than low-grade cancers.
Cancer cells act differently than normal cells. Cancer cells multiply out of control. Unlike normal cells, they make new cells that are not needed and do not die when they should. The cancer cells build up to form a primary tumor.
Cancer cells can also grow into (invade) other tissues. Normal cells do not do this. Over time, the primary tumor can grow large and invade tissues outside the ovary. Ovarian cancer often invades the fallopian tubes.
Unlike normal cells, cancer cells can spread to other parts of the body. This process is called metastasis. Ovarian cancer cells can break off (shed) from the primary tumor to form new tumors on the surface of nearby organs and tissues. These are called “implants” or “seeds.” Implants that grow into supporting tissues of nearby organs are called invasive implants. When these implants can be seen on a computed tomography (CT) scan, it is called “carcinomatosis.”
Cancer cells can also spread through blood or lymph vessels. Lymph is a clear fluid made of white blood cells that help fight germs.
It travels in small tubes (vessels) to lymph nodes. Lymph nodes are small groups of disease-fighting cells that remove germs from lymph. Lymph vessels and nodes are found all over the body.
Testing for ovarian cancer
Your doctor may suspect ovarian cancer if you have certain symptoms. Symptoms are changes in the body that you can feel or notice. Unfortunately, ovarian cancer may not cause symptoms until the tumor has grown very large or has spread. The most common symptoms include:
- Feeling bloated
- Heartburn and indigestion
- Pain in the pelvis or belly (abdomen)
- Trouble eating or feeling full fast
- Feeling the need to urinate often or urgently
- Pain during sex
These symptoms can also be caused by other common health conditions. Ovarian cancer is more likely to be the cause if the symptoms are:
- New (began less than 1 year ago)
- Frequent (occurring more than 12 days each month)
- Becoming more severe over time.
Other symptoms may develop if the mass is large or if fluid builds up in your abdomen. Your doctor may be able to feel a mass by doing a pelvic or abdominal exam (described later in this chapter). The buildup of fluid is called ascites. Ascites may cause swelling of the abdomen. If your doctor suspects ovarian cancer based on your symptoms, you will have testing as described in this chapter.
Some tests are done at the initial visit, while others are done soon after a diagnosis is made. It is helpful to ask your doctor which tests you will have and when you can expect the results. The results of certain tests and evaluations described in this chapter provide information needed to plan treatment.
Testing helps determine the clinical (pre-surgery) stage. The clinical stage provides a “best guess” of how far the cancer has spread. It is a best guess because surgery is needed in order to know exactly how much cancer is in the body.
Testing also helps determine whether you are a good candidate for surgery. Having surgery first may not be an option based on the size and location of the tumor. It may also not be a good option for those who are elderly, frail, have trouble doing daily activities, or who have other serious health conditions. If your doctor decides that having surgery first isn’t a good choice for you, see page 25.
To diagnose ovarian cancer, a sample of tissue must be removed from your body for testing. This is called a biopsy. Doctors test tumor tissue to check for cancer cells and to look at the features of the cancer cells. Most often, the biopsy is done during surgery to remove ovarian cancer.
Sometimes a biopsy is done to help diagnose ovarian cancer before surgery or other planned treatment. This may be the case if the cancer has spread too much to be removed by initial surgery. In such cases, a fine-needle aspiration (FNA) biopsy or paracentesis may be used. An FNA biopsy uses a very thin needle to remove a small sample of tissue from the tumor. For paracentesis, a long, thin needle is inserted through the skin of the belly (abdomen) to remove a sample of fluid.
The biopsy samples are sent to a pathologist for testing. A pathologist is a doctor who is an expert in testing cells to find disease.
The pathologist views the samples with a microscope to look for cancer cells. If the cells are cancerous, the pathologist assesses their appearance and other features.
Review of tumor tissue
Sometimes ovarian cancer is confirmed by a prior surgery or biopsy performed by another doctor. In this case, your doctors will need to review all of the prior results. This includes results of the surgery, biopsy, and tests of tissue that was removed. A pathologist will examine the tumor tissue with a microscope to make sure it is ovarian cancer. Your doctors will also want to know if any cancer was left in your body after surgery. All of this will help your current doctors plan treatment.
Abdominal and pelvic exam
Your doctor will do a physical exam of your abdomen and pelvis. This is called an abdominal and pelvic exam. For the abdominal exam, your doctor will feel different parts of your belly. This is to see if organs are of normal size, are soft or hard, or cause pain when touched. Your doctor will also feel for signs of fluid buildup (ascites) in the belly area or around the ovaries.
During the pelvic exam, your doctor will feel for abnormal changes in the size, shape, or position of your ovaries and uterus. A special widening instrument, called a speculum, will be used to view your vagina and cervix. A sample of cells may be removed for testing. This is known as a Pap test. It is used to detect cervical cancer or pre-cancer, not ovarian cancer.
Imaging tests take pictures of the inside of your body. Doctors use imaging tests to check if there is a tumor in your ovaries. The pictures can show the tumor size, shape, and location. They can also show if the cancer has spread beyond your ovaries.
Different types of imaging tests are used to look for ovarian cancer, plan treatment, and check treatment results. Before the test, you may be asked to stop eating or drinking for a few hours. You may also need to remove metal objects from your body. The types of imaging tests used for ovarian cancer are described next.
Ultrasound is often the first imaging test used to look for ovarian cancer. It uses sound waves to make pictures of the inside of the body. Ultrasound is good at showing the size, shape, and location of the ovaries, fallopian tubes, uterus, and nearby tissues. It can also show if there is a mass in the ovary and whether the mass is solid or filled with fluid.
A hand-held device called an ultrasound probe is used. There are two types of ultrasounds that may be used to look for ovarian cancer– transabdominal and transvaginal.
For a transabdominal ultrasound, a gel will be spread on your abdomen and pelvis. The gel helps to make the pictures clearer. Your doctor will place the probe on your skin and guide it back and forth in the gel.
For a transvaginal ultrasound, your doctor will insert the probe into your vagina. This may help the doctor see your ovaries more clearly. Ultrasounds are generally painless, but you may feel some discomfort when the probe is inserted.
Computed tomography (CT)
A CT scan uses x-rays to take many pictures of areas inside of the body from different angles. All of the x-ray pictures are combined to make one detailed picture of the body part.
CT scans of your chest, abdomen, and/or pelvis may be given along with other initial tests to look for ovarian cancer. This type of scan is good at showing if the cancer has spread outside of the ovaries. But, it is not good at showing small tumors. A CT scan may also show if nearby lymph nodes are bigger than normal. This can be a sign that the cancer has spread.
A substance called contrast will be used to make the pictures clearer. Before the scan you will be asked to drink a large glass of oral contrast. A contrast agent will also be injected into your vein. This is referred to as intravenous (“IV”) contrast. It may cause you to feel flushed or get hives. Rarely, serious allergic reactions occur. Tell your doctors if you have had bad (allergic) reactions to IV contrast in the past.
A CT scanner is large and has a tunnel in the middle. During the scan, you will lie face up on a table that moves through the tunnel. The scanner will rotate an x-ray beam around you to take pictures from many angles. You may hear buzzing, clicking, or whirring sounds during this time. A computer will combine all the x-ray pictures into one detailed picture.
Magnetic resonance imaging (MRI)
An MRI scan uses radio waves and powerful magnets to take pictures of the inside of the body. It does not use radiation. This type of scan is good at showing the spine and soft tissues. An MRI scan of your abdomen and pelvis may be used to look for ovarian cancer if the ultrasound was unclear. An MRI scan of your chest may be used to look for signs of cancer spread. This test may also be used to check treatment results and to assess for cancer spread to other parts of the body.
Getting an MRI scan is similar to getting a CT scan but takes longer to complete. The full exam can take 1 hour or more. You will lie on a table that moves through a large tunnel in the scanning machine. The scan may cause your body to feel a bit warm. Like a CT scan, a contrast agent will be used to make the pictures clearer.
Positron emission tomography (PET)
In some cases, CT or MRI may be combined with PET. A PET scan shows how your cells are using a simple form of sugar. A sugar radiotracer is first put into your body with an injection into a vein. The radiotracer emits a small amount of energy that is detected by the machine that takes pictures. Active cancer cells use sugar faster than normal cells. This means that cancer cells look brighter in the pictures. PET is very good at showing small groups of cancer cells. This test may also be useful for showing if ovarian cancer has spread.
Chest x-ray An x-ray uses small amounts of radiation to make pictures of organs and tissues inside the body. A tumor changes the way radiation is absorbed and will show up on the x-ray picture. A chest x-ray can be used to show if cancer has spread to your lungs. This test may be given with other initial tests when ovarian cancer is first suspected or found. It may also be ordered to check treatment results. A chest x-ray is fast and painless.
If the cancer is advanced, you may have a diagnostic laparoscopy before treatment. The purpose is to learn the extent of the cancer in the abdomen. It helps your doctors decide whether surgery can be performed first, or if chemotherapy should be given first to shrink the cancer and make surgery easier. This minimally invasive procedure involves making a tiny cut in the abdomen. A thin tube with a light and a camera (laparoscope) is used to view the lining of the abdomen and the surface of organs in the abdomen. Tissue samples are taken and tested for cancer cells in a lab.
Family history and genetic testing
Ovarian cancer most often occurs for unknown reasons. However, about 15 out of 100 ovarian cancers are due to changes (mutations) in genes that are passed down from a parent to a child. This is called hereditary ovarian cancer.
Hereditary ovarian cancer is most often caused by mutations in 1 of 2 genes: breast cancer gene 1 (BRCA1) or breast cancer gene 2 (BRCA2). ABRCA mutation increases the risk of developing ovarian, breast, and some other cancers. Everyone has BRCA1 and BRCA2 genes. When working properly, they are helpful. They prevent abnormal cell growth by repairing damaged cells.
Another cause of hereditary ovarian cancer is Lynch syndrome, also known as hereditary nonpolyposis colorectal cancer (HNPCC) syndrome. Lynch syndrome is the most common cause of hereditary colon cancer, but can also cause ovarian and other cancers.
Ovarian cancer associated with a BRCA mutation or Lynch syndrome usually starts at a younger age than non-hereditary ovarian cancer. Using your age, health history, and family history, your doctor will assess how likely you are to have hereditary ovarian cancer.
Genetic testing can tell if you have a mutation in the BRCA genes, or in other genes that play a role in hereditary cancer. If initial treatment works well, BRCA status (whether you have a BRCA mutation) plays an important role in guiding decisions about maintenance therapy. Maintenance therapy is discussed in more detail later in this guide.
Genetic testing is recommended for everyone diagnosed with ovarian cancer. This testing may be done through your gynecology or oncology care team, or by a genetic counselor. Genetic testing is done on normal tissue–either blood, saliva, or a cheek swab. Those with a positive genetic test or who have a strong cancer family history should see a health expert. This is typically a genetic counselor. A genetic counselor has special training to help patients understand changes in genes that are related to disease. The genetic counselor can tell you more about how likely you are to have hereditary ovarian cancer.
More information on BRCA mutations is provided in the Biomarker testing section on page 17.
You can read more about Ovarian Cancer, its treatment methods and follow-up after treatment in the full text of the recommendations for patients by downloading it below.