What is ovarian cancer?
Ovarian cancer is when malignant cells develop from tissues of the ovaries, fallopian tubes, or peritoneum, the membrane that lines the abdominal and pelvic organs. Ovarian cancer is the second-most common gynecologic cancer (after uterine cancer), and the 10th-most common cancer in women.
At first, ovarian cancer may show no symptoms. Symptoms tend to be vague and usually don’t develop until ovarian cancer is in advanced stages. Symptoms are common to other conditions and include gas, bloating, diarrhea or constipation, and fatigue. Other symptoms include pain or a sensation of pressure in the pelvis, abdomen, back or legs. Less commonly, some women may also experience shortness of breath, abnormal vaginal bleeding, or the need to urinate frequently.
The cause of ovarian cancer is not known, but it does seem to run in some families. Having children at an early age and having multiple children reduces the risk of ovarian cancer, as does taking birth control pills. Certain inherited genetic mutations increase the risk of developing ovarian cancer.
During ovarian cancer diagnosis, your doctor will determine the stage based on how widespread it is. This usually involves surgery to determine the size of the primary tumor, if cancer cells are in your lymph nodes, and if the cancer has spread to other organs. Early ovarian cancers may be treated with surgery alone, with an excellent prognosis. Chemotherapy may also be recommended, depending on the stage of the cancer.
Seek prompt medical care if you have symptoms that suggest ovarian cancer, especially if symptoms persist for more than a couple of weeks. Seek immediate medical care (call 911) if you, or someone you are with, experience severe symptoms, such as the inability to urinate or have a bowel movement, severe abdominal or pelvic pain, or uncontrolled or heavy bleeding.
Who develops ovarian cancer?
Around 22,000 women in the United States are diagnosed with ovarian cancer annually. The incidence, or rate of ovarian cancer continues to decline as it has in all age groups since the 1980s. Studies indicate:
- A woman’s lifetime risk of developing cancer is 1.3%, or 1 in 78. The probability is 1 in 870 for a 40-year-old woman compared to 1 in 265 for a 70-year-old woman.
- Ovarian cancer risk increases with age. For epithelial ovarian cancer, diagnoses peak in women in their late 70s.
- Ovarian cancer is most common in non-Hispanic white women compared to other races and ethnicities in the United States.
What are the different types of ovarian cancer?
Types of ovarian cancer include:
- Epithelial cell ovarian cancer starts from cells on the outer surface of the ovary. Epithelial cell cancer is the most common type (90%) of ovarian cancer. Ovarian carcinoma is another name for it. Epithelial carcinomas include high-grade (more aggressive) and low-grade (less aggressive) subtypes. Most high-grade epithelial carcinomas start in the fallopian tube.
- Germ cell ovarian cancer starts from eggs (ova; single ‘ovum’). Germ cell tumors account for 2 to 3% of ovarian cancers.
- Stromal, or sex cord-stromal cell ovarian cancer starts from cells in the ovary that make estrogen and progesterone (and sometimes testosterone). Because these hormones can cause abnormal vaginal bleeding, even after menopause, ovarian stromal tumors are often diagnosed at an early stage. About 2% of ovarian cancer diagnoses are stromal tumors.
What are the different stages of ovarian cancer?
Ovarian cancer stages depend on the size of the tumor and whether the cancer has spread to the lymph nodes or other organs. Lower stage ovarian cancers are more likely to respond to treatment and typically have a better outlook.
Doctors most commonly use surgery, CT scans, and PET/CT scans to stage ovarian cancer. Still, staging can be difficult because tumors can be very small and not visible by eye—even on a PET/CT scan. A microscopic analysis of washings from inside the pelvic or larger abdominal cavity is necessary for accurate staging. With this information, you and your doctor can develop an individualized treatment plan.
There are four ovarian cancer stages:
- Stage I (1) ovarian cancer is in one ovary or fallopian tube or both ovaries or fallopian tubes. Stage I accounts for very few ovarian cancer diagnoses, but it has a very high survival rate.
- Stage II (2) ovarian cancer extends from the ovary to the fallopian tube, or there are tumors on the uterus, fallopian tube, or other tissues within the pelvis. Stage II includes primary peritoneal cancer—cancer that starts in the peritoneum. Stage II makes up about 10% of ovarian cancer diagnoses and may be curable with conventional treatments.
- Stage III (3) ovarian cancer involves one or both ovaries or fallopian tubes and has either grown beyond the pelvic cavity or spread (metastasized) to specific lymph nodes within the peritoneum, or both. Most women (85%) have stage IIIC ovarian cancer at diagnosis, which is when the cancer is larger than 2 cm and may involve the liver or spleen.
- Stage IV (4) ovarian cancer is distant metastatic cancer, with cancer-positive fluid around the lung (pleural effusion) or metastasis to the liver, spleen, or other organs beyond the abdominal cavity. From 12 to 21% of diagnoses are stage IV.
What are the symptoms of ovarian cancer?
Early ovarian cancer often produces no symptoms in its earliest stages, when it is most treatable. In other cases, initial symptoms of ovarian cancer can be vague and may seem to be gastrointestinal in origin.
Symptoms of ovarian cancer are also common to other conditions. However, the difference is ovarian cancer symptoms do not typically come and go; they can become more bothersome or severe with time.
Common symptoms of ovarian cancer include:
- Swelling, distension or bloating in the stomach area
- Lower abdominal (pelvic) pain or pressure
- Abnormal vaginal bleeding, which can be severe
- Constipation or diarrhea
- Feeling full quickly or not being able eat very much
- Gas, indigestion or upset stomach
- Back pain
- Pain during sexual intercourse
- Sensation of pressure in the abdomen or pelvis
- Shortness of breath
- Urinating more often or more urgently
It may be easy to ignore these symptoms and explain them away. Talk with your doctor if you are experiencing any new symptoms that persist for a few weeks or longer.
Serious symptoms that might indicate a life-threatening condition
In some cases, complications of ovarian cancer can be life threatening. Seek immediate medical care (call 911) if you, or someone you are with, have any of these potentially life-threatening symptoms including:
- Inability to urinate or have a bowel movement
- Respiratory or breathing problems, such as shortness of breath, difficulty breathing, labored breathing
- Severe abdominal, pelvic or back pain
- Uncontrolled or heavy bleeding
What causes ovarian cancer?
The exact cause of ovarian cancer is not known. Scientists are learning more about ovarian cancer causes by studying factors that reduce the risk of ovarian cancer. These include taking oral birth control for four or more years, pregnancy, hysterectomy, and tubal ligation.
The root cause of all cancer is DNA damage and mutations in key genes required for normal cell growth and behavior. In ovarian cancer, both inherited and non-inherited (acquired) gene mutations increase the risk of developing the disease.
Inherited defects include BRCA1 and BRCA2 mutations, which are also involved in breast and pancreatic cancers. Mutations in these genes greatly increase the risk of ovarian cancer. However, heredity accounts for only about 10% of ovarian cancer cases. The other 90% involves acquired gene mutations, which take many years to develop and cause cancer.
Although it does seem to run in certain families, ovarian cancer can occur in women who have no family history of cancer. Early age at first delivery, multiple pregnancies, and birth control pills seem to lower the risk of ovarian cancer, while estrogen-only hormone replacement therapy (ERT, which is unopposed estrogen replacement—without complementary progesterone replacement therapy) may increase the risk.
What are the risk factors for ovarian cancer?
A number of factors increase the risk of developing ovarian cancer. Not all women with risk factors will get ovarian cancer.
Know your personal risks of ovarian cancer. You may have a higher risk for ovarian cancer if you:
- Are age 55 or older. Most ovarian cancers develop after menopause.
- Are 5 feet 8 inches or taller. Greater height carries a slight increased risk.
- Are Caucasian. More non-Hispanic white women compared to other races and ethnicities in the United States develop the condition.
- Have a family history of ovarian cancer, especially if you have a mother, sister, aunt or grandmother with ovarian cancer
- Have inherited genes, such as BRCA1 or BRCA2, that increase your risk of developing breast cancer and other cancers
- Have endometriosis
- Had your first pregnancy after the age of 35
- Have never given birth
- Have used estrogen-only hormone replacement (estrogen therapy without progesterone)
- Used fertility drugs
- Used talcum powder around your vaginal area
Lifestyle risk factors
These lifestyle factors can also increase your risk:
- Eating a high-fat diet
- Being overweight (obesity)
How do you prevent ovarian cancer?
Prevention is taking action to lower your chances of getting a disease. Some risk factors for ovarian cancer can be avoided, others cannot. You may be able to lower your risk of ovarian cancer if you:
- Become pregnant and have your first child before you’re 35
- Breastfeed your baby
- Have surgery to remove both ovaries, called a prophylactic oophorectomy. Some women who have a high genetic risk of ovarian cancer choose to have this surgery to prevent ovarian cancer.
- Have a tubal ligation or hysterectomy
- Use oral contraceptives for four or more years. The longer you used these medicines, the lower your risk of ovarian cancer.
A healthy lifestyle may also lower your risk of ovarian cancer, including:
- Eating a balanced healthy diet, low in fats
- Getting regular physical exercise
- Maintaining a healthy weight
- Not smoking
Talk with your doctor about your specific risks. To help your doctor determine your personal risk of ovarian cancer, bring your personal and family health history to your appointment.
How do doctors diagnose ovarian cancer?
Doctors diagnose ovarian cancer by evaluating patient symptoms, performing a pelvic exam, and reviewing imaging and other test results.
Tests for diagnosing ovarian cancer include:
- Pelvic exam
- Transvaginal ultrasound
- CA-125 blood test, which measures the level of cancer antigen 125
- CT (computed tomography), MRI (magnetic resonance imaging), and PET (positron emission tomography)
- Biopsy to remove a tissue sample to check it for cancer. Biopsy is the only way to know for sure if the tissue is cancerous.
- Laparoscopic surgery, after a cancer diagnosis, to help determine the stage (extent and location) of cancer. Laparoscopic surgery may also be used to remove early stage ovarian cancer.
Ovarian cancer screening tests
Screening tests for ovarian cancer include the CA-125 test and transvaginal ultrasound. Ovarian cancer screening is an option for women at high risk for ovarian cancer, including women with a family history of ovarian or breast cancer, a personal history of breast cancer, or mutations in genes linked to ovarian or breast cancer (or mutations linked to hereditary cancer syndromes).
Major medical and health organizations do not recommend ovarian cancer screening for women who are not high-risk because studies show screening can cause more harm than good and does not decrease the ovarian cancer death rate. Research is ongoing for more specific ovarian cancer screening tests for all women.
How is ovarian cancer treated?
The goal of ovarian cancer treatment is to cure the cancer if possible, or bring about a complete remission of the disease. Remission means that there is no longer any sign of the disease in the body, although it may recur later.
Treatment for ovarian cancer depends on the type, stage, and the overall health of the patient. The most common treatment for ovarian cancer is combining surgery and chemotherapy.
Ovarian cancer treatment options include:
- Surgery includes removing as much cancer as possible; this is called debulking. Ovarian cancer surgery can be curative for early stage cancer (stages I and II). During surgery, the abdominal and pelvic cavities are explored for evidence of cancer spread.
- Chemotherapy is used before or after surgery (or both). Chemotherapy is also an option for advanced cases of ovarian cancer in which surgery is not an appropriate treatment.
- Radiation therapy is not commonly used to treat ovarian cancer, but it may be used to relieve symptoms of cancer that has spread to other organs.
- Hormone therapy reduces estrogen levels or blocks its function or production.
- Biologic therapy to recruit the body's immune system to fight cancer. This is cancer immunotherapy.
- Targeted therapy attacks cancer cells with less damage to normal cells. Some of these therapies depend on the gene mutations present in the cancer cells.
- Clinical trials, which are currently testing other promising new therapies and treatments for ovarian cancer
To ensure the best chance for a cure or remission, carefully follow your treatment plan. After your treatment is complete, it is important to continue regular follow-up visits with your doctor as recommended.
Other therapies may be added to help boost your general state of health and offset any side effects of treatment. These treatments may include:
- Antinausea medications
- Blood cell growth factors to increase the number of healthy blood cells destroyed by chemotherapy
- Dietary counseling to help you maintain strength and nutritional status
- Pain medications as needed
Some complementary treatments may help some women to better deal with ovarian cancer and its treatments. These treatments, sometimes referred to as alternative therapies, are used in conjunction with traditional medical treatments.
Complementary treatments are not meant to substitute for traditional medical care. Be sure to notify your doctor if you are consuming nutritional supplements or homeopathic (nonprescription) remedies as they may interact with the prescribed medical therapy.
Complementary treatments may include:
- Massage therapy
- Nutritional dietary supplements, herbal remedies, tea beverages, and similar products
In cases in which ovarian cancer has progressed to an advanced stage and has become unresponsive to treatment, the goal of your treatment may shift from curing the disease to focusing on measures to keep you comfortable and maximize your quality of life.
Hospice care involves medically controlling pain and other symptoms while providing psychological and spiritual support as well as services to support the patient’s family members.
How does ovarian cancer affect quality of life?
Most cancer treatment centers ask patients to answer questionnaires on how the patient is doing physically and mentally throughout the cancer journey. It is a measure of the patient’s health and well-being from the patient’s perspective. The formal name for it is health-related quality of life (HRQoL).
One purpose of this measure is to understand how ovarian cancer testing and treatment may affect the patient’s health and ability to function over time. It helps cancer experts know, for example, whether a treatment’s benefits outweigh (or not) the potential negative effects on patient health. HRQoL is important to measure because women who report higher HRQoL tend to have a better ovarian cancer prognosis.
Ovarian cancer treatment has both positive and negative effects. Treatment may improve cancer symptoms, mood, and enjoyment of life, but it can also involve significant side effects and recovery time.
Ovarian cancer impacts quality of life because of:
- Physical recovery and side effects of surgery, which in most cases includes loss of fertility and abrupt menopause
- Side effects of chemotherapy including hair loss, fatigue, memory problems (‘chemo brain’), and nerve pain
Many ovarian cancer clinical trials include measuring HRQoL to better understand the type, severity and management of women’s symptoms and side effects. Knowing the effect of a potential new treatment on a patient’s quality of life and well-being is critical to the support of a new ovarian cancer therapy for a larger population.
What are the potential complications of ovarian cancer?
Complications of untreated ovarian cancer can be serious, even life threatening in some cases. You can help minimize your risk of serious complications by following the treatment plan you and your healthcare professional design specifically for you.
Complications of ovarian cancer include:
- Adverse effects of treatment
- Ascites (fluid buildup in the abdomen)
- Bowel or bladder obstruction
- Electrolyte disturbances
- Ovarian torsion (twisting of the ovary)
- Pleural effusion (fluid buildup around the lungs)
- Spread of cancer
Some complications of ovarian cancer, such as ovarian torsion (twisting of the ovary) or bowel obstruction, can be severe or even life threatening.
What is the survival rate and prognosis for ovarian cancer?
Most women diagnosed with ovarian cancer—about 75%—have advanced disease with a poor prognosis. The National Cancer Institute estimates just under 14,000 deaths from ovarian cancer in 2020. Ovarian cancer is the fifth-leading cause of cancer deaths across all ages, after lung, breast, colorectal, and pancreatic cancer.
A common cancer statistic is a 5-year relative survival rate, which means the percentage of people alive five years from diagnosis time relative to people who do not have ovarian cancer. The 5-year relative survival rate for all cases of ovarian cancer is about 49% (48.6%, years 2010 - 2016). The survival rate decreases with age and the stage of cancer at time of diagnosis. Women younger than 65 have a higher survival rate than women older than 65.
Ovarian Cancer Awareness
New and developing information on how ovarian cancer develops and the genetics of ovarian cancer is guiding screening, prevention and treatment strategies. With time, effective strategies will become a standard of care and decrease the burden of ovarian cancer.
September is Ovarian Cancer Awareness month.