Ovarian cancer is relatively rare, affecting about 2% of women. However, it can be a very tricky cancer to recognize in early stages and difficult to treat in later stages. Additionally, there is still not a good screening tool for ovarian cancer, as there is for cancers of other reproductive organs.
Dr. Daniel Donato Jr., FACOG, FACS, gynecologic oncology surgeon at Rocky Mountain Cancer Centers (RMCC) said ovarian cancer is one of the most difficult cancers he treats for a few different reasons.
“The first one is that we don’t have a good screening test for the population,” Dr. Donato said. “The second one is when you look at the symptoms that lead you to think about ovarian cancer – or even entertain the thought – the symptoms are so vague and so nonspecific.”
Many patients and even medical providers may attribute symptoms to a more benign cause until they can make a diagnosis based on a CT scan or other imaging after several months of searching for the source of symptoms. His message to other providers is to consider ovarian cancer – especially in post-menopausal women with nonspecific abdominal complaints. Dr. Donato said an ultrasound is a safe, cost-effective tool for evaluating these patients.
Signs of Ovarian Cancer
As previously noted, the signs of ovarian cancer are often ambiguous, but signs and symptoms of ovarian cancer that patients may present with include:
- Difficulty eating or feeling full quickly
- Urinary symptoms such as needing to urinate more frequently or urgently
- Palpable mass in the lower abdomen which could be ovarian or other types of cancer, but it could also be from noncancerous causes such as an ovarian cyst, aneurysm, or lipoma
- Pain in the pelvic region or lower abdomen
- Pressure or fullness in the pelvic region
- Unexplained weight loss
- Back pain
- Changes in bowel habits such as constipation
Early detection of localized ovarian or fallopian tube cancer has a five-year relative survival rate of about 93%-98%. Unfortunately, only about 20% found are early-stage ovarian cancers. Most ovarian cancers are found at stages 3 or 4, when cancer cells are found in surrounding tissue or lymph nodes, or have already metastasized. The five-year survival rate for regional metastasis of ovarian or fallopian tube cancer is 54%-94% and for distant metastasis, the survival rate drops to 31%-74%.
A prompt referral to a specialist is one of the best evidence-based interventions available to reduce ovarian cancer mortality. You can improve your patient’s chance of survival by referring them to a specialist at the first signs of ovarian cancer or if a patient's history puts them at higher risk.
Risk Factors for Developing Ovarian Cancer
Certain factors may increase your patient’s risk of developing ovarian cancer, including:
- Advanced age
- History of cancer, especially breast cancer
- History of endometriosis
- Family history of certain genetic mutations associated with ovarian cancer
- Hormone replacement therapy use
- Reproductive history, including women who are nulliparous, had their first full-term pregnancy at 35 or older, or had prior fertility treatment with IVF
Testing for Ovarian Cancer
Abdominal exam – palpation of the abdomen to feel for the presence of any abnormal masses
Pelvic exam – including a bimanual exam to palpate the ovaries
Ultrasound – transvaginal ultrasound may be preferred in patients with symptoms of ovarian cancer, those with high CA-125 levels, or those with ovarian mass on physical exam
Biopsy – a biopsy of the ovaries, either through paracentesis or surgical laparoscopy
Genetic testing – Genetic mutations associated with ovarian cancer are usually autosomal dominant. Some genetic mutations or inherited syndromes that can increase ovarian cancer risk include:
- BRCA-1 gene mutation – carries a lifetime risk of 35%-70% of developing ovarian cancer
- BRCA-2 gene mutation – carries a lifetime risk of 15%-30% of developing ovarian cancer
- Lynch syndrome, also called hereditary nonpolyposis colon cancer (mutation of the MLH-1, MSH-2, MSH-6, EPCAM, or PMS-2 gene) – carries a lifetime risk of 10% of developing ovarian cancer and increases the risk of colon and uterine cancer
- MUTYH-associated polyposis (MUTYH gene mutation) – increases the risk of bladder, colon, and small intestine cancer
- Peutz-Jeghers syndrome (STK11 gene mutation) – causes polyps in the stomach and intestine in the first couple of decades of life and can also increase the risk of digestive tract cancer (esophageal, stomach, colon, and small intestine cancer)
Other gene mutations linked to ovarian cancer (CHEK2, NBN, MRE11A, PALB2, RAD51C, RAD51D, ATM, MSH6, BRIP1, and TP53) – some of these mutations are also linked to breast and pancreatic cancer.
CA-125 (cancer antigen 125) level – a biomarker blood test that can help look for the level of CA-125 which may be elevated in patients with ovarian cancer. However, this is typically not recommended in pre-menopausal women who are at average risk of developing ovarian cancer because CA-125 can be falsely elevated. Inflammatory conditions, endometriosis, and fibroids can elevate CA-125. Patients who would be a candidate for CA-125 testing include post-menopausal patients with nonspecific abdominal complaints and an ovarian mass on exam. Additionally, high-risk patients with a family history that genetically predisposes them to developing ovarian cancer could be potentially screened in combination with ultrasound. However, even in high-risk populations, CA-125 testing has not proven to identify ovarian cancer at earlier stages.
OVA1 test – the OVA1 blood test measures five different proteins to identify ovarian cancer – although it’s not good at early detection – promptly refer patients with an abnormal OVA1 test to a specialist. The five proteins measured in an OVA1 test include CA-125 II, prealbumin, transferrin, apolipoprotein A1 (Apo A-1), and Beta-2 microglobulin (B2M).
Screening – There are currently no routine screening recommendations for someone at average risk of developing ovarian cancer, but for those with certain genetic mutations that increase the risk of developing ovarian cancer, screening with transvaginal ultrasound and CA-125 blood test may be considered in some cases. However, even in high-risk patients, current screening has not been proven to reduce the risk of dying from ovarian cancer. Prophylactic removal of the ovaries and fallopian tubes – salpingo-oophorectomy – can help reduce the risk of ovarian cancer in patients with a genetic predisposition but may not be a good option for women of child-bearing age who would like to have children. In these patients, screening with CA-125 and transvaginal ultrasound may be performed a couple of times a year until they are ready for a more effective method of preventing ovarian cancer, prophylactic salpingo-oophorectomy. Prophylactic salpingo-oophorectomy is the treatment of choice for ovarian cancer prevention in high-risk patients, and it is typically performed in women ages 40 to 45.
Most Common Types of Ovarian Cancer
While most epithelial ovarian tumors are benign, the most common ovarian cancer type is epithelial ovarian carcinoma. Epithelial ovarian carcinomas can be broken down into various subtypes including but not limited to:
- Serous carcinomas – make up 52% of epithelial ovarian carcinomas and is classified at low-grade or high-grade; high-grade is fast-growing and typically responds best to chemotherapy.
- Mucinous carcinomas – slow-growing, affecting about 6% of women, and generally occurs in older women
- Endometrioid carcinomas – slow-growing, but typically does not respond as well as other subtypes to treatment
- Clear cell carcinomas – not as common, but carries a good prognosis in early stages
Other cancers similar to epithelial ovarian cancer and are less common include:
- Primary peritoneal cancer
- Fallopian tube cancer
If your patients experience signs of ovarian cancer, the specialists at Rocky Mountain Cancer Centers can provide a prompt evaluation. Refer a patient.