By Melissa Laitner, PhD, MPH, SWHR Director of Science Policy
In 2020, SWHR is bringing attention to the need for advances in diagnostic and screening tests across a variety of diseases and conditions to improve the health of women. In the first of a two-part blog series, we discuss ovarian cancer risk, mortality, diagnostics, and screening.
Over 20,000 women will be diagnosed with ovarian cancer this year in the United States, and less than half of them will still be alive in five years.
Comparatively, women diagnosed with breast cancer have an almost 90% chance of surviving five years after diagnosis. Ovarian cancer is the deadliest gynecological cancer and one of the most underfunded cancers when considering the relatively high mortality rate.
SWHR spoke with Dr. Julia A. Smith of NYU Langone Health, a medical oncologist specializing in cancer risk assessment and screening, to better understand why outcomes for ovarian cancer are so poor. Smith explained that the survival rate for ovarian cancer patients changes drastically based on how early they are diagnosed.
If the disease is caught at an early stage, before it spreads to other parts of the body, women have a 92% chance of surviving for five years post-diagnosis. However, more than three-fourths of women are not diagnosed until later stages.
Part of the reason for the delay in diagnosis is how ovarian cancer develops. “Ovarian cancer is not like lung cancer or breast cancer, where the cells become abnormal, start to divide uncontrollably, and then form a mass,” Smith explained. “Here what happens is that cells on the fallopian tube or ovary start to divide and then fall off into the abdomen and pelvis. There isn’t a big mass or nodule that sits there.”
Once the cancer cells leave the fallopian tube or ovary, the disease has already progressed to an advanced stage. “When these cells are in the abdomen and pelvis, they can attach to any organ or vessel within that cavity,” Smith said, noting that at this point mortality risk increases significantly.
Another factor contributing to delay in diagnosis is that ovarian cancer often presents subtly, with very common, vague symptoms such as abdominal bloating, abdominal discomfort, and feeling full quickly. Not surprisingly, these symptoms are often attributed to more common maladies such as food intolerance or gastrointestinal issues like irritable bowel syndrome.
“The symptoms tend to be less specific and less targeted than symptoms in an organ, where the cancer would be growing and affecting function of the organ right away.” As a result, some patients may wait months before seeing a health care provider — and their provider, in turn, may take weeks or months to reach a true diagnosis.
Traditional technology used to screen or diagnose women with ovarian cancer is outdated and has low predictive value for women with normal risk for the disease, according to the United States Preventative Services Task Force. As such, asymptomatic women are advised against getting screened if they don’t have a previously determined risk for the disease.
Current tools include a blood test to measure a protein called CA-125 and transvaginal ultrasound. But the blood test was developed in the 1980s and often results in false positives because CA-125 is also higher when women are menstruating or pregnant. Even when combined with an ultrasound, these tools are not conclusive. Most women who receive positive screens will require surgery to remove all or part of the ovary before they receive a definitive diagnosis.
“We need new advanced techniques to detect ovarian cancer when it’s still in early stages, confined to ovary and fallopian tube, because that is highly curable,” Smith said. “We also need better screening technology.”
The fact that more reliable screening methods do not exist for ovarian cancer is in stark contrast to other diseases. For example, women receive regular mammograms to screen for breast cancer beginning at age 40 or 50 years old, and women over age 21 should receive Pap tests every three years to screen for cervical cancer. Men are recommended to consider periodic screening for prostate cancer between ages 55-69 years.
Although ovarian cancer is one of the more rare cancers and diagnosis rates have declined over the past few decades, for certain groups of women, the disease is a much more pressing issue. Half of all ovarian cancers are diagnosed after age 62, making it a particular concern for older adults.
Even more significantly, mutations in certain genes — those most commonly associated with breast cancer — increase risk for ovarian cancer. This includes both BRCA1 and BRCA2 mutations, among others. Women with BRCA1 mutations have a 44% chance of developing ovarian cancer by the age of 80. Those with BRCA2 mutations have a 17% chance. This is compared to a 1.3% risk of ovarian cancer in the general population.
“In the high-risk population, there is some evidence that screening tests may be useful, but it’s not definitive,” Smith said.
The lack of advancement in diagnostics, screening, and treatment for ovarian cancer has led to stagnant survival rates for patients over the past 25 years. A continued lack of progress could result in many more lethal diagnoses.
For patients wondering what steps they can take to protect their health, Smith recommended considering how to minimize negative outcomes. “The first thing to do is to find out whether you are at elevated risk and whether genetic testing would be useful,” she said. “People who are at elevated risk because of family or genetic history need to be in the hands of a gynecological oncologist who is advising them about reproductive health issues.”
“We know that oral contraceptives, if there’s no contraindication, if used for five years, significantly decreases one’s risk of ovarian cancer,” she added.
Most importantly, Smith said women need to “listen to their bodies and trust their bodies. If they know symptoms are persisting, they need to report concerns. If they’re not getting attention, they need to find another doctor.”
Luckily, there is innovation on the horizon that may improve diagnosis and prognosis for ovarian cancer. Stay tuned for part two of this series, where SWHR will discuss issues with ovarian cancer screening, hope for new diagnostic tools, and what can be done from a system’s perspective to improve upon these issues.