Ovarian cancer is the leading cause of death among the five major gynecologic malignancies, which include cervical, uterine, vaginal and vulvar cancers.
Approximately 3,000 Canadians are diagnosed with ovarian cancer each year. Once known as the silent killer, this type of cancer has lower survival rates than breast and other more common forms of the disease. It is estimated that over half of those diagnosed will not survive more than five years. However, new research and new drugs are giving patients renewed hope.
Dr. Stephanie Lheureux, Site Lead of the Gynecologic Oncology Clinic at UHN's Princess Margaret Cancer Centre and Westaway Chair in Ovarian Cancer Research, shares her insights. Tracey Keighley-Clarke, an ovarian cancer survivor, also talks about her experience.
Dr. Stephanie Lheureux
What sparked your initial interest in ovarian cancer?
I am really passionate about women's health. Early in my training, I was involved in gynecological medicine and my patients really sparked my interest. So many women had so many questions about ovarian cancer. Why can't we detect it earlier? Why is it resistant to treatment? Why is it so hard to cure? I wasn't able to answer those questions and so I wanted to do research in this area and try to find answers and not accept this fate.
What are the risk factors for ovarian cancer?
About 20 per cent of ovarian cancers are hereditary and that is why we recommend a full genetic work-up on patients to see if they have genetic markers. This has an impact for the patient and for their families so they can find out if they carry the gene. Remember Angelina Jolie? She had the BRCA1 gene mutation and a family history. So she underwent prophylactic surgery to prevent breast and ovarian cancer and had her breasts, ovaries and fallopian tubes removed.
Other risk factors for high-grade serious ovarian cancer include: increasing age, nulliparity (women who have never given birth); age of first menstruation and age of menopause. Research is still ongoing in this area and also to investigate the risks for other rare types of ovarian cancer.
What are the challenges around detecting ovarian cancer early?
Silent killer is still an appropriate way to describe it. Ovarian cancer is often not found until it is advanced and then it is harder to cure. Also, the rate of recurrence is high.
There is no screening test for ovarian cancer and at the early phases, it may not be symptomatic, or symptoms may be thought to be related to menopause or other conditions. The location of the ovaries means it is hard to detect and it is not something we can feel quickly, like a lump in your breast. The second challenge is biological and relates to how ovarian cancer develops. We have discovered that the early lesions start at the end of the fallopian tube. The precursors of the tumour can stay there for some years. You can't feel or detect it until suddenly the cancer has advanced.
What are the symptoms?
The symptoms can be vague and vary from patient to patient. Some patients have constipation, bloating, feel full quickly, changes in bladder habits or pain. Some patients think they are having bowel issues and have a colonoscopy, but nothing shows up on this procedure, as the tumour is external to the bowel. So it can be quite a difficult cancer to diagnose.
Can you share the promise of new forms of treatment?
Ovarian cancer will return in most patients. We have drugs known as Poly (ADP-ribose) polymerase (PARP) inhibitors, which have been shown to be effective in some patients at keeping cancer at bay after completion of chemotherapy. However, once the cancer returns, treatment is more challenging. We have scientific studies looking at new strategies and other ways to block cancer cell growth. For example, the
NEO trial assessed the combination of systemic therapy and secondary cytoreductive surgery, also known as debulking surgery where surgery aims to remove all of the tumor.
Another study, called
REVOLVE, uses detailed cancer information at the molecular level to direct personalized treatment when the cancer has returned and is resistant to PARP inhibitors. This approach is unique to each patient. This trial has the potential to change the way women with recurring ovarian cancer are treated in Canada and lay the groundwork for new areas of drug development.
Why do patients with ovarian cancer often lose weight?
When ovarian cancer progresses, it can cause a lot of bowel symptoms. Patients can feel full and this impacts their appetite. They eat less and lose weight. Other patients may have fluid in their abdomen that creates pressure and this makes them feel nauseated.
For patients who receive treatment, there can also be a change in the way they taste food. All these factors contribute to weight loss. But once the cancer is controlled and patients feel better, they will tolerate food again and usually gain back the weight they have lost.
Any final thoughts?
I'm excited that there are new investigations underway and innovative clinical trials for ovarian cancer because regular therapy hasn't shown it is able to keep the cancer from recurring. It is a hopeful time for patients and researchers. We can't yet cure it, but, compared to 10 years ago, we can prolong and extend life with a better quality of life for patients. I am hopeful that research will provide promising new strategies to be free from the fear of ovarian cancer.
Patient Tracey Keighley-Clarke
I was a nurse for 33 years.
I knew all about prevention and screening and regularly had a mammogram, pap test and colonoscopy. In the summer of 2020, I developed a rash and went to my family doctor.
About eight weeks later I noticed some abdominal bloating. Concerned, I called my family doctor - he tried to order a CT scan but the wait times during COVID were extensive. My family doctor saw me and sent me immediately to the emergency department where I received an abdominal ultrasound.
It confirmed a significant amount of fluid in my abdomen as well as two large ovarian masses. One was the size of a grapefruit and the other, the size of an orange. I had had no other symptoms.
But as a nurse, I knew the significance of these findings.
I was immediately referred to a gynecologic-oncologist. Four weeks later I had a full hysterectomy followed by four months of chemotherapy. I continued to work and was followed closely by the cancer team.
Thirteen months after my diagnosis, a CT scan showed a recurrence. I had to have four more months of chemotherapy. The cancer returned five months after that.
By then, the disease was making my life difficult. I had fluid retention, abdominal pressure, shortness of breath, brain fog, fatigue, nausea, weight loss and back pain. Even getting out of bed was exhausting. I felt defeated and that time was running out.
Fortunately, I was referred to Princess Margaret Cancer Centre to explore experimental treatment options. Dr. Lheureux told me about a three-year clinical trial called REVOLVE and helped me get access to it. I was patient number one.
A team of experts do a genetic breakdown of your tumour to identify biomarkers that can predict treatment response. This helps determine the best treatment. It is precision medicine - not a cookie cutter approach, but one that recognizes each person is unique.
Since I've been on the trial, my tumours have shrunk and my quality of life has improved.
I have been able to travel with my husband, attend both my daughters' university graduations and celebrate my eldest daughter's wedding.
Without this treatment, I would have missed these milestones and the opportunity to make memories. As a "cancer pioneer," I am grateful to be a part of changing the future of ovarian cancer treatment. I feel like I'm a partner in my own care and I am grateful for that.
