Researcher holds vaccine
There are no routine ovarian cancer screenings for women. Yes, ovarian cancer is rare and represents 1% of new cases cancer diagnoses every year in the US. But it is a serious disease, as only half of the nearly 20,000 women diagnosed each year survive past five years. That is quite low compared to breast cancer, which has a five-year survival rate more than 90%.
Scientists at Cancer Research UK recently received £600,000 to develop the first vaccine against ovarian cancercalled OvarianVax. Medical oncologist and immunologist Dr. Matthew Block of the Mayo Clinic is working on developing a vaccine against ovarian cancer, using artificial white blood cells from patients with ovarian cancer. The vaccine will target a protein called folic acid receptor alpha, which is associated with ovarian cancer.
Dr. Block shared, “One way the two vaccines differ is in the target patient population. The vaccine developed by Mayo Clinic is used in patients who already have ovarian cancer; both as a means to prevent recurrence of ovarian cancer in patients in cancer remission (secondary prevention), and in a regimen for the treatment of active ovarian cancer. In contrast, although the UK vaccine will first be tested in patients with ovarian cancer, it is primarily being developed to prevent ovarian cancer from developing in patients who are at risk of the disease but have never had it (primary prevention).
Dr. Block explained that the commercially available human papillomavirus (HPV) vaccine, Gardasil 9, prevents cancer by preventing long-term infection with cancer-causing HPV strains. He explained: “Since ovarian cancer is not known to be caused by a virus, ovarian cancer vaccines target proteins expressed by the tumor cells rather than viral proteins. Similar to the commercially available HPV vaccine, the UK ovarian cancer vaccine is designed to be used in patients who do not have cancer, with researchers looking at whether it will substantially reduce the risk of cancer.
Dr. Melissa Frey, gynecologic oncologist and director of the Genetics and Personalized Cancer Prevention Program at Weill Cornell Medicine, explains that there are currently no reliable methods to screen for ovarian cancer. For women at higher risk for ovarian cancer, for example women with a BRCA1/2 mutation or Lynch syndrome, some doctors recommend transvaginal (pelvic) ultrasound and a CA-125 blood test.
Dr. Frey shared, “These tests may result in increased detection of early-stage ovarian cancer compared to late-stage ovarian cancer. However, these tests are not included in the National Comprehensive Cancer Network guidelines for women with a hereditary predisposition to ovarian cancer, and large clinical trials suggest that these tests do not translate into improved survival for people diagnosed with ovarian cancer. Dr. Frey explained that there are several groups working on cancer vaccines and that there are open clinical trials for this purpose. “However, we are still several years away from an FDA-approved vaccine for this indication.”