Two coincidentally timed announcements offer good and bad news on ovarian cancer. Despite not being one of the most common forms of cancer, ovarian cancer is particularly hard to treat, so it causes a disproportionate number of deaths. Now, a new approach to treatment has passed Phase I clinical trials, but the problem could become worse before it reaches the market, since a separate study found that chlamydia, whose frequency is rising, is a risk factor.
Although the ovaries are less susceptible to cancer than the breasts or bowel, 22,000 American women are diagnosed with the condition each year, with similar rates elsewhere. Moreover, the disease has fewer distinctive early symptoms than many of its counterparts, so by the time it is detected, surgery, chemotherapy, and radiation may all be required. With less than half of those diagnosed surviving after five years, even with good medical facilities it is a major cause of death. Even pre-emptive action, such as that taken by Angelina Jolie to have her ovaries removed, doesn't totally guarantee protection.
In a webinar briefing on research to be presented at the American Association for Cancer Research (AACR) Annual Meeting in April, Dr Britton Trabert of the National Cancer Institute announced two independent studies reporting cancer rates are higher among women with Pgp3 antibodies, which indicate past chlamydia infection.
Antibodies for a variety of other sexually transmitted infections were not associated with increased risk of ovarian cancer. Given that chlamydia is the most common cause of pelvic inflammatory disease (PID), and PID has been associated with ovarian cancer before, the results are unsurprising, but still concerning as chlamydia rates increase.
Hopes for better treatment options rose, however, with the publication in Clinical Cancer Research of a trial of an immune therapy to treat the disease. Like all Phase I trials, this was done on a small sample of people, in this case, just 14. Consequently, it's too early to tell just how effective the TPIV200 therapeutic vaccine used in the trial really is, particularly since there was no randomized control group.
Nevertheless, the trial succeeded in its goals of generating a lasting immune response, and almost doubled the usual period before disease progression began. Only one patient experienced a serious side effect. The findings were sufficiently promising and a Phase II trial is already underway. The trial also tested the responses of eight breast cancer patients to the vaccine, with similar positive effects.
TPIV200 targets the Folate Receptor Alpha, implicated in ovarian and some breast cancers. It stimulates the immune system's helper cells to attack tumors, which should, in theory, produce far fewer side effects than chemotherapy, and has the potential to be extended to many other types of cancer.