By Georgia McCann, MD, associate clinical professor, associate program director, Obstetrics and Gynecology
Ovarian cancer is responsible for more deaths than any other cancers of the female reproductive system and is the fifth leading cause of cancer death among women in the United States, according to the American Cancer Society.
Why is this the case?
Unlike mammograms, colonoscopies and pap smears, which are good screening tests to detect precancerous changes or early-stage cancers, there is no such screening test for ovarian cancer.
Multiple screening strategies have been studied. These include transvaginal ultrasound and a cancer antigen 125 (CA 125) blood test. These strategies have been studied alone or in combination with each other. Unfortunately, no studies to date have shown a reduction in ovarian cancer mortality.
Both transvaginal ultrasound and CA 125 can have high false-positive rates. This means women may be unnecessarily exposed to invasive tests as a result. High levels of CA 125 may be present with other conditions apart from cancer.
Why early detection is crucial for this insidious disease
Mortality from ovarian cancer is directly related to a patient’s staging at diagnosis.
Women with stage 1 ovarian cancer — in which the cancer is still contained within the ovaries — and stage 2 — in which the cancer involves other pelvic structures like the uterus, but all the cancer is contained within the pelvis — have significantly better survival rates than women diagnosed with later stages.
Women with stage 1 ovarian cancer have an 89% five-year survival rate and women with stage 2 have a 71% five-year survival rate.
Unfortunately, about 75% of women with ovarian cancer are diagnosed after the cancer has spread outside of the ovaries. Most commonly, women will have carcinomatosis — a condition in which the cancer has spread outside the ovaries and throughout the abdominal cavity. Women diagnosed with stage 4 ovarian cancer have distant metastasis, meaning the cancer has spread outside of the abdomen or involves organs such as the liver or spleen.
According to current data, women with stage 3 ovarian cancer have a five-year survival rate of about 40 percent. Women diagnosed with stage 4 have a 20% five-year survival rate.
Most women with stage 3 ovarian cancer who are treated with surgery and chemotherapy have a complete response with no visible cancer at the end of treatment. However, many women will ultimately experience a recurrence of the cancer. That is why the five-year survival rate is low for women diagnosed with stage 3 or 4 ovarian cancer. Once the cancer returns, it’s incurable.
The promising news is that over the past five years, new maintenance strategies have been used in women with ovarian cancer after completion of primary chemotherapy.
Following primary therapy of surgery and chemotherapy, certain patients may benefit from taking poly(ADP)-ribose polymerase, or PARP inhibitors. PARP inhibitors work by preventing cancer cells from repairing their DNA.
Depending on the patient’s unique needs, the enzymes can be taken for a two-to-three-year period. Doctors are hopeful that more women are being cured with this strategy and that we may see a decrease in mortality from ovarian cancer.
Who may benefit most from PARP inhibitors?
Women who tend to have a better response to PARP inhibitors have ovarian tumors that are positive for homologous recombination deficiency (HRD) in which cancer cells have difficulty repairing themselves. The same concept applies for women who are positive for breast cancer gene (BRCA) mutations, because PARP inhibitors can help stop cancer cells with damaged DNA from repairing and replicating themselves.
While the majority of women who finish primary therapy (surgery and chemotherapy) are receiving PARP inhibitors, some may not. This is because the data supporting the use of PARP inhibitors is not as strong in women who do not have a BRCA mutation or whose tumors are not HRD positive.
In some cases, the side effects of PARP inhibitors may outweigh the benefits. The most common side effects include fatigue, nausea and bone marrow abnormalities. A rare side effect of PARP inhibitors is secondary cancer of the bone marrow.
Ovarian cancer symptoms
Ovarian cancer affects women of all ages. However, most commonly, it occurs in post-menopausal women.
While it is unknown exactly how long it takes for ovarian cancer to spread from the ovaries, the progression appears to happen quicker than some other cancers. For example, it can take five to 10 years before a precancerous lesion of the cervix becomes a cancer.
Because women are often diligent about seeing their gynecologist, it’s important to note that pap smears are solely meant for early cervical cancer detection, not ovarian cancer detection. That’s why it’s important to know the symptoms for ovarian cancer, which can include the following:
- Unexplained weight loss.
- Abdominal pain, bloating, or increased size of the abdomen.
- Feeling full quickly. It may take only a small volume of food to feel full.
- Feeling the need to urinate frequently.
If you experience any of the above symptoms and they do not go away, please visit your primary care physician or gynecologist for further evaluation.
Clinical trial studying ovarian cancer risk reduction
Currently, I serve as the principal investigator of a clinical trial studying whether certain surgical procedures reduce the risk of ovarian cancer in women with the BRCA1 mutation. This mutation is associated with increased risk of breast and ovarian cancers, among other types of cancers.
Recruitment for this trial at the Mays Cancer Center at UT Health San Antonio is currently open. The trial examines how well two surgical procedures (bilateral salpingectomy — the surgical removal of fallopian tubes — and bilateral salpingo-oophorectomy — the surgical removal of both the fallopian tubes and ovaries) work to reduce the risk of ovarian cancer for women with BRCA1 mutations.
This study may help doctors determine if the two surgical procedures are nearly the same for ovarian cancer risk reduction for women with BRCA1 mutations.
Please click here to learn more about the clinical trial including eligibility and inclusion criteria.
Purple Heals support group
In 2013, I started the Purple Heals support group for women with all gynecologic cancers and their caregivers in San Antonio. The group provides a safe and supportive space to connect, share experiences and talk about issues group members are encountering.
The group was started in honor of my first patient who maintained a positive outlook and provided pep talks to other patients when they were struggling with their diagnosis.
The support group includes patients, survivors and their caregivers. Caregivers can include anyone caring for a patient. The in-person group initially met monthly before the COVID-19 pandemic. Since the pandemic, the group moved to a closed Facebook page. Currently, we’re working on returning to the in-person sessions.
To learn more about the group or request to join, click here.
To schedule an appointment with Georgia McCann, MD, call 210-450-9500, or you can request an appointment online at cancer.uthscsa.edu/appointments.