Ovarian Cancer Symptoms, Diagnosis and Treatment
Medically Reviewed by Dr. Samantha Miller, MBChB
Ovarian cancer is one of the lesser-known forms of cancer and can be asymptomatic at first, or present with non-specific symptoms. The American Cancer Society estimates that over 21,000 people in the United States will be diagnosed with ovarian cancer in 2021.
Ovarian cancer occurs when abnormal cells in the ovaries grow and divide out of control. The ovaries are responsible for producing an ova (egg) on a roughly monthly basis throughout a person’s childbearing years and are responsible for producing the reproductive hormones estrogen, progesterone and testosterone. Women usually have two ovaries, which are situated in the pelvis close to the fallopian tubes and uterus.
Ovarian cancer tends to occur more often in older women, with about half of the women diagnosed with ovarian cancer each being over the age of 63. However, ovarian cancer does also occur in young women, particularly where there’s a family history of similar cancers.
If the cancer is detected early, the long-term outlook is very good. Unfortunately, the cancer is often not detected until it spreads to other organs. At that point, the cancer is more difficult to treat and is often fatal.
Symptoms of Ovarian Cancer
The symptoms associated with ovarian cancer can be vague, meaning they’re not specific to ovarian cancer, and can go unnoticed for many years. This leads to ovarian cancer often being misdiagnosed, or diagnosed at a late stage. Symptoms include:
- Abdominal pressure, fullness or “heaviness”
- Abdominal swelling or bloating
- Weight loss
- Unusual vaginal bleeding
- Unexplained back pain
- Pain during or after sex
- Persistent indigestion, gas or nausea
- Changes in bowel habits, such as constipation
- Changes in urinary frequency, for example needing to go more often
- Loss or decrease of appetite
- Early satiety (feeling full soon after eating a small meal)
- Increased abdominal girth (you may notice that your clothes are fitting tighter around your waist)
- Persistent fatigue
- Pelvic discomfort or pain
Some of the symptoms of ovarian cancer include relatively common discomforts. Menstrual irregularities, tiredness and increased frequency of urination are also symptoms that don’t necessarily seem out of the ordinary in older women who make up the largest percentage of ovarian cancer cases. Unfortunately, patients are more likely to notice symptoms of ovarian cancer once the cancer has started to spread beyond the ovaries, a process that’s called metastasis. Only about 20% of ovarian cancer cases are diagnosed in the early stages, mainly because early symptoms are easy to miss.
Causes and Risk Factors for Ovarian Cancer
There’s no one cause of ovarian cancer, and most cases arise sporadically due to a random gene mutation causing some cells to grow and multiply out of control, eventually forming tumors. If left untreated, cancerous cells can break off and spread to other areas of the body.
While the exact causes of ovarian cancer are unknown, certain risk factors contribute to a person’s likelihood of developing the disease. Women over the age of 55 — particularly those who have gone through menopause — are more likely to be diagnosed with ovarian cancer.
A family history of ovarian cancer is a significant risk factor, and there are known gene mutations that put an individual at an increased risk of developing ovarian cancer. The most well-known of these genes are the BRCA1 and BRCA2 gene mutations, which are also associated with an increase in breast cancer. It’s estimated that an individual with a BRCA1 gene mutation has a nearly 40% lifetime risk of developing ovarian cancer.
If you have family members who have been diagnosed with breast or ovarian cancer, you may be offered genetic testing to see if you have those gene mutations. Other risk factors include a personal history of breast, colon or uterine cancers, along with endometriosis, obesity and having had no prior pregnancies.
Pregnancy and breastfeeding are associated with a lower risk of developing ovarian cancer. Taking oral contraceptives, which contain hormones, also correlates with a lower risk. Reproductive surgery, such as tubal ligations, also affect hormone levels and could decrease the risk of ovarian cancer. Overall, it’s a good rule of thumb to maintain a healthy, active lifestyle and schedule regular checkup appointments with your various healthcare providers for earlier potential diagnosis.
Diagnosing Ovarian Cancer
There are several different diagnostic tests that can help detect ovarian cancer. Often the first test is a blood test for a marker called CA125. CA125 is a protein that people’s bodies commonly overproduce when they have ovarian cancer. Its levels are elevated in more than 90% of patients with advanced-stage ovarian cancer and 50% of patients with early-stage ovarian cancer. However, having a normal CA125 test result does not rule out ovarian cancer, and having a high CA125 result does not necessarily mean you have ovarian cancer. Doctors typically use other tests in conjunction.
It’s important to look at the ovaries themselves to assess for any obvious tumors or signs of cancer. This may be via ultrasound scan or computed tomography (CT) scan. To obtain a diagnosis of what type of ovarian cancer you have, your doctor may perform a biopsy, which aims to take a small sample of cells from your ovary to see what type of cells they are. The doctor may also take a sample of the fluid inside your abdomen, called peritoneal fluid, to see if there are cancer cells there. Genetic testing may also be necessary to see if you have any of the high-risk genetic mutations that predispose you to developing ovarian cancer.
Once you’ve been diagnosed with ovarian cancer, you may undergo further imaging tests, such as CT, magnetic resonance imaging (MRI) or positron emission tomography (PET) scans. These are to see if the cancer has spread beyond your ovary and to provide staging. Stages help your doctor categorize how advanced the cancer is and where it has spread and can also help them determine your treatment.
- Stage 1: The cancer cells have not spread beyond your ovary, fallopian tube or the fluid inside your abdomen.
- Stage 2: The cancer has spread from your ovary into nearby areas inside your pelvis, such as your uterus, bowel or bladder.
- Stage 3: The cancer has progressed from your ovary to your peritoneum (the covering of your internal organs) outside your pelvis.
- Stage 4: The cancer has spread to other organs such as your lung, spleen or liver.
This is not a comprehensive list of staging criteria.
The type of cell where the cancer originates also determines the type of cancer as well as the treatment and the prognosis.
- Epithelial tumors: This is cancer that begins in the cells that form the outer layer of tissue of your ovary. This is the most common form of ovarian cancer. Epithelial cancers can be subdivided into types called serous, mucinous, endometrioid and clear cell.
- Germ cell tumors: This is the type of cancer that begins in the egg-producing cells. This type of cancer more often affects young women.
- Stromal tumors: This type of cancer starts in hormone-producing tissues.
Treating Ovarian Cancer
Treatment for ovarian cancer usually involves both surgery and chemotherapy. The surgery is often extensive and may involve the removal of both ovaries, fallopian tubes, the uterus, the surrounding lymph nodes and a layer of the surrounding fatty tissue, called the omentum. The cancer often spreads to this tissue.
A less-extensive form of surgery may be possible if the cancer is detected early enough. During surgery, the surgeon will also remove as much of the cancer as possible from the abdominal cavity, a procedure called surgical debulking.
Chemotherapy is often used either before or after surgery. This is the use of medication that kills off cancer cells. Common medications include Paclitaxel (Taxol) and Cisplatin (Platinol). Chemotherapy is usually administered intravenously (IV) or by injection directly into the abdomen.
Depending on your case, you may also need radiation. This is the use of high-energy rays to kill off cancer cells. Radiation is targeted only to the area of your body where the cancer is present and may be used in conjunction with surgery and/or chemotherapy.
For some patients, surgery and other treatments may not be the best plan. In that case, people may receive palliative care, which aims to relieve symptoms rather than prolonging life if the doctor determines that’s more suitable.
It’s estimated that over 70% of people with ovarian cancer who undergo surgery and chemotherapy with a curative aim will achieve clinical remission. However, not all people with ovarian cancer will be well suited to this type of management, such as those whose cancer has already spread to distant organs. As with every type of cancer, the earlier the diagnosis is the better the chances of survival are.
According to the American Cancer Society, the five-year survival rate for those with stage I cancer is over 90%. This number decreases as the cancer progresses, with those whose cancer is at stage IV having a five-year survival rate of 18%. It’s also important to note that many people who are ovarian cancer survivors live much longer than five years after their diagnosis; this is only the number that’s used for compiling statistics.