The Role of the Microbiome in Treating Women With Recurrent Ovarian Cancer

Ovarian cancer is widely understood to be a challenging cancer to treat, as remission and survival rates are lower than many other gynecologic malignancies. Despite current efforts to treat the disease, many women will go on to experience recurrent disease. In fact, 40% to 50% of women who are in clinical remission will experience an episode of disease recurrence within 3 years of completing treatment with first-line chemotherapy. For those women who experience disease recurrence, their expected survival is only in the 12- to 18-month range, with less than 10% surviving the disease at the 5-year mark after receiving salvage therapy.¹

In addition to standard chemotherapy, clinical trials, can at times, increase a woman’s survival. An interesting study out of Roswell Park Cancer Institute in Buffalo is currently enrolling approximately 40 women into a phase II clinical trial to evaluate the use of pembrolizumab (Keytruda), bevacizumab (Avastin), and oral cyclophosphamide (Cytoxan) and its effects not only on survival, but also on antitumor immune response. The clinical trial subjects all have recurrent ovarian, fallopian tube, or primary peritoneal cancer.²

Where the study differs from others is their interest in evaluating the body’s microbiome of the gut, vagina, and other organs, such as the skin. Women participating in the trial will undergo collection of blood, tumor, stool, vaginal, and skin microbiome samples, as well as other required testing.

“Our biggest hope is that by trying these three drugs in combination, we can significantly extend the lives of patients with recurrent ovarian cancer. We also hope to minimize the side effects associated with chemotherapy drugs, and to markedly improve the quality of our patients’ lives,” said Emese Zsiros, MD, PhD, FACOG, lead study investigator and Assistant Professor of Oncology in Roswell Park’s Department of Gynecologic Oncology. “We will be looking at potential biomarkers that will tell us who can most benefit from this therapy combination and to better understand how cancer cells and immune cells communicate with one another so that we can design better medications to kill cancer efficiently.”²

Zsiros goes on to explain that, “There’s a whole new area of research suggesting that what’s going on in our gut, our gut flora, has a huge influence on your overall health and happiness, and this study will extend that work into some new directions.”²

Currently, there is ongoing research evaluating the importance of the gut flora in maintaining immune function in other diseases/general population, and it will be interesting to see the results of this clinical trial and how the data can be used to better treat women with these gynecologic malignancies.

References:

1. Texas Oncology. Recurrent Ovarian Cancer: Overview. 2016.
2. Roswell Park Cancer Institute. New Ovarian Cancer Immunotherapy Study Poses Question: Can Microbiome Influence Treatment Response? News release. 2016 Nov 28.