Ovarian and Fallopian Tube Cancer Guide

Anatomy of the Ovaries

The ovaries are part of the female reproductive system. There are two ovaries, one on each side of the uterus. Before menopause, the ovaries are almond-shaped and about 1.5-2 cm wide. They contain what are called germ cells or eggs.

The ovaries are the main source of estrogen and progesterone for the body. These hormones influence breast growth, body shape, body hair, and regulate the menstrual cycle and pregnancy. During and after menopause, the ovaries stop releasing eggs and producing certain hormones.

Anatomy of the Fallopian Tubes

The fallopian tubes are small ducts that connect the ovaries to the uterus. They are part of the female reproductive system. Typically, the female reproductive system has two fallopian tubes, one on each side of the uterus. During ovulation, which usually happens every month, an egg is released from one ovary and passes through the fallopian tube to the uterus.

Anatomy of the Peritoneum

The peritoneum is a tissue that covers the abdomen and most organs in the abdomen. The peritoneum covers the uterus, bladder, rectum, and ovaries, as well as the fallopian tubes. A fold of this tissue called the omentum covers and connects the organs in the abdomen. A fluid called peritoneal fluid covers the surface of the tissue. This fluid helps the organs move in the abdomen and prevents them from sticking together.

About Ovarian, Fallopian Tube, and Peritoneal Cancer

The term "ovarian cancer" is often used to describe cancers that start in the cells of the ovary, fallopian tube, or peritoneum. These cancers are closely related and are treated in the same way.

In this guide, this group of cancers is referred to as "ovarian cancer" in general, as peritoneal cancer is relatively rare. When the term "ovarian cancer" is used, it includes fallopian tube and peritoneal cancer, as it may not be clear where the cancer started.

These types of cancer begin when healthy cells in these areas change and grow uncontrollably, forming a mass called a tumor. The tumor can be cancerous or benign. A cancerous tumor is malignant, which means it can grow, invade, and spread to other parts of the body. A benign tumor means the tumor can grow but will not spread.

An ovarian cyst is another phenomenon that should be considered in this context. It represents an abnormal growth of tissue that forms on the surface of the ovary and contains fluid. It can occur during a normal menstrual cycle and usually disappears without treatment. Ordinary ovarian cysts are not cancerous.

Recent studies show that most ovarian/fallopian tube/peritoneal cancers are high-grade serous cancers, and in most cases, the cancer actually starts at the tip or outer end of the fallopian tubes. It then spreads to the surface of the ovaries and can spread beyond them.

Based on these updated findings, when discussing contraception to avoid future pregnancy, some doctors recommend removing the fallopian tubes instead of tying the tubes to reduce the risk of ovarian/fallopian tube cancer. Some doctors also recommend removing the fallopian tubes under certain conditions.

Since the surfaces of the ovaries, the lining of the fallopian tubes, and the covering cells of the peritoneum are made up of the same types of cells, most of these diseases look the same under a microscope. Rarely, peritoneal cancer can develop after the ovaries and fallopian tubes have been removed.

Prevention of Ovarian Cancer

There is no sure way to prevent ovarian cancer. But there may be ways to reduce the risk:

• Consider taking birth control pills: Ask your doctor if birth control pills (oral contraceptives) might be right for you. Taking birth control pills can reduce the risk of ovarian cancer. But these medications are associated with side effects, so discuss whether the benefits outweigh these risks.
• Discuss your risk factors with your doctor: If you have a family history of breast and ovarian cancer, mention it to your doctor.

Types of Ovarian Cancer

The type of cell where the cancer begins determines the type of ovarian cancer and helps the doctor determine the best treatment. Types of ovarian cancer 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 types of ovarian cancer.
• Germ Cell Tumors: These rare types of ovarian cancer usually occur at a younger age.

Symptoms of Ovarian Cancer

When ovarian cancer first develops, it might not cause any noticeable symptoms. When symptoms of ovarian cancer appear, they are usually attributed to other, more common conditions. Signs and symptoms of ovarian cancer can include:

• Abdominal bloating
• Quickly feeling full when eating
• Weight loss
• Pelvic discomfort
• Fatigue
• Back pain
• Changes in bowel habits, such as constipation
• Frequent need to urinate

Risk Factors for Ovarian Cancer

Factors that can increase the risk of ovarian cancer include:

• Older Age: The risk of ovarian cancer increases with age. It is most often diagnosed in older adults.
• Inherited Gene Changes: A small percentage of ovarian cancers are caused by changes in genes inherited from your parents. Genes that increase the risk of ovarian cancer include BRCA1 and BRCA2. These genes also increase the risk of breast cancer.
• Family History of Ovarian Cancer: If you have blood relatives who have been diagnosed with ovarian cancer, you may have an increased risk of the disease.
• Being Overweight or Obese: Being overweight or obese increases the risk of ovarian cancer.
• Hormone Replacement Therapy After Menopause: Taking hormone replacement therapy to manage signs and symptoms of menopause can increase the risk of ovarian cancer.
• Endometriosis: Endometriosis is a painful condition where tissue similar to the tissue that lines the inside of the uterus grows outside the uterus.
• Age When Menstruation Started and Ended: Beginning menstruation at an early age or starting menopause at a later age, or both, may increase the risk of ovarian cancer.

Causes of Ovarian Cancer

It’s not clear what causes ovarian cancer, although 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. The DNA of the cell contains instructions that tell the cell what to do. The changes tell the cells to grow and multiply rapidly, creating a mass (tumor) of cancer cells. The cancer cells continue living when healthy cells die. They can invade nearby tissues and break off from the initial tumor to spread (metastasize) to other parts of the body.

Diagnosing Ovarian Cancer

Tests and procedures used to diagnose ovarian cancer include:

• Pelvic Examination: During a pelvic exam, the doctor inspects the vagina and palpates the pelvic organs. The doctor also visually examines the external genitalia, vagina, and cervix.
• Imaging Tests: Tests such as ultrasound or CT scans of the abdomen and pelvis can help determine the size, shape, and structure of the ovaries.
• Blood Tests: Blood tests can include organ function tests that can help determine your overall health. Your doctor might also test your blood for tumor markers that indicate ovarian cancer. For example, the cancer antigen (CA) 125 test can detect a protein that is often found on the surface of ovarian cancer cells. These tests can’t tell your doctor whether you have cancer, but they can give clues about the diagnosis and prognosis.
• Surgery: Sometimes your doctor can’t be certain of your diagnosis until you undergo surgery to remove an ovary and inspect it for signs of cancer.
• Genetic Testing: Your doctor might recommend testing a sample of your blood to look for gene changes that increase the risk of ovarian cancer. Knowing that you have an inherited DNA change helps your doctor make decisions about your treatment plan. It might also be useful to share this information with your blood relatives, such as your siblings and children, as they might have a risk of these gene changes.

Stages and Grading of Ovarian Cancer

Once it’s confirmed that you have ovarian cancer, the doctor will use the information from tests and procedures to determine the cancer's stage. Stages of ovarian cancer range from 1 to 4, which are often indicated by Roman numerals I to IV. The lowest stage indicates that the cancer is confined to the ovaries. At stage 4, the cancer has spread to distant parts of the body.

Stage 1: Early Stage Cancer

• Stage 1a: Cancer is only in one ovary or fallopian tube.
• Stage 1b: Cancer is in both ovaries or both fallopian tubes.
• Stage 1c: Cancer is in one or both ovaries or fallopian tubes, and one or more of the following has occurred:
• The surrounding tissue (capsule) of the ovary or fallopian tube has ruptured. This may have allowed cancer cells to leak into the abdomen or pelvis.
• There are cancer cells on the surface of the ovaries or fallopian tubes.
• There are cancer cells in the fluid in the abdomen or pelvis.

Stage 2: Cancer is in one or both ovaries or fallopian tubes and has grown into nearby areas in the pelvis, or cancer has started in the peritoneum but affects only areas within the pelvis.

• Stage 2a: Cancer involves the uterus, fallopian tubes, or ovaries.
• Stage 2b: Cancer involves other structures in the pelvis, such as the intestines or bladder.

Stage 3: Cancer is in one or both ovaries or fallopian tubes or the peritoneum and has spread to:

• The lymph nodes in the back of the abdomen (abdomen). These are called retroperitoneal lymph nodes.
• The peritoneum outside the pelvis.
• Stage 3a1: Cancer has spread to the lymph nodes in the abdomen.
• Stage 3a2: Very small amounts of cancer have spread to the peritoneum outside the pelvis. There may also be cancer in the lymph nodes in the abdomen.
• Stage 3b: There are areas of cancer on the peritoneum outside the pelvis. These areas are less than 2 cm in diameter. There may also be cancer in the lymph nodes in the abdomen.
• Stage 3c: There are areas of cancer on the peritoneum outside the pelvis that are larger than 2 cm in diameter. There may also be cancer in the lymph nodes in the abdomen. The cancer may have spread to the capsule around the liver and spleen, but not to these organs.

Stage 4: Cancer has spread to other parts of the body outside the abdomen.

• Stage 4a: Cancer has caused fluid to build up in the lining of the lungs (pleura). This is called a pleural effusion.
• Stage 4b: Cancer has spread to the inside of the liver or spleen. Or the cancer has spread to lymph nodes or organs outside the abdomen, such as the lungs.

Grading of Ovarian, Fallopian Tube, or Peritoneal Cancer

Grading describes how cancer cells look under a microscope compared to normal cells. Knowing the grade helps your doctors plan your treatment options.

Here’s how ovarian, fallopian tube, and primary peritoneal cancer are graded:

• Grade 1 (low grade or well-differentiated): Cancer cells look a lot like normal cells. They usually grow slowly and are less likely to spread.
• Grade 2 (moderate or intermediate grade): Cancer cells look more abnormal. They grow a little faster.
• Grade 3 (high grade or poorly differentiated): Cancer cells look very different from normal cells. They usually grow faster.

Treatment of Ovarian Cancer

Treatment for ovarian cancer usually involves a combination of surgery and chemotherapy. In certain cases, other treatments such as targeted therapy, immunotherapy, and others might be used depending on the stage of the disease. Detailed information on all treatment methods for ovarian cancer can be found on this page.

How is Epithelial Ovarian/Fallopian Tube Cancer Treated?

Most cases of ovarian/fallopian tube cancer are epithelial carcinoma. A large portion of them are high-grade serous carcinoma (HGSC). Generally, treatment for early-stage HGSC ovarian/fallopian tube cancer often includes surgery and adjuvant chemotherapy. Treatment for more advanced high-grade serous carcinoma includes surgery with adjuvant chemotherapy and/or targeted therapy, neoadjuvant chemotherapy followed by surgery, or only chemotherapy if surgery is not possible.

How are Germ Cell Tumors of the Ovary Treated?

Typically, the first treatment for germ cell tumors of the ovary is surgery. In almost all cases, doctors can perform the surgery in a way that preserves fertility. Doctors might recommend adjuvant chemotherapy after surgery, depending on the stage and subtype of germ cell cancer. Chemotherapy usually consists of a combination of bleomycin (available as a generic drug), cisplatin (available as a generic drug), and etoposide (available as a generic drug), administered intravenously.

How are Stromal Tumors Treated?

Stromal tumors are a rare form of ovarian cancer. They are found in the connective tissue that holds the ovaries together. Generally, for stage I stromal tumors, treatment usually consists only of surgery. For high-risk tumors in the early stage or stage III or IV disease, doctors might apply combination chemotherapy.

How is Metastatic Ovarian, Fallopian Tube, and Peritoneal Cancer Treated?

New treatments for these types of cancer include experimental combinations of chemotherapy, targeted therapy, and another type of systemic therapy called immunotherapy or biological therapy. These combinations are designed to enhance the body's natural defenses to fight cancer. Since the benefits of these methods are still being studied, their risks must be weighed against potential improvements in symptom relief and life extension. Palliative and supportive care are also extremely important for relieving symptoms and side effects.