Researchers at The University of Arizona Cancer Center at St. Joseph's Hospital and Medical Center in Phoenix have discovered that many women with low-grade serous carcinoma of the ovary or peritoneum have seen their tumors stabilize or shrink after taking a regular dose of the compound selumetinib. The findings, published in the Feb. 14 edition of The Lancet Oncology, show that selumetinib targets a mutation in the MAPK pathway for patients with low-grade serous carcinoma, allowing for treatment on previously chemoresistant tumors. "This is a potentially important breakthrough for the Gynecologic Oncology Group," said John Farley, MD, a gynecologic oncologist in the Division of Gynecologic Oncology and the Department of Obstetrics and Gynecology at the Creighton University School of Medicine at St. Joseph's Hospital and Medical Center, a Dignity Health Member. The Gynecologic Oncology Group is a non-profit international organization with the purpose of promoting excellence in the quality and integrity of clinical and basic scientific research in the field of gynecologic malignancies. Dr. Farley is part of the University of Arizona Cancer Center at St. Joseph's and is board certified in obstetrics and gynecology with a subspecialty certification in gynecologic oncology. He is a retired decorated Army colonel who completed a residency in obstetrics and gynecology and a fellowship in gynecologic oncology at Walter Reed Army Medical Center. He is the first author on this study. This study was initially developed in 2007, with 52 patients enrolled for the Phase II clinical trial between December 2007 and November 2009. Patients were given 50 milligrams of selumetinib orally twice daily. Of those participants, eight had a measurable decrease in tumor size, seven had partial responses and 34 patients saw their tumors stabilize. The findings suggest that inhibitors of the MAPK pathway warrant further investigation in patients with low-grade ovarian cancer. "There just aren't very good treatments for low-grade ovarian cancer, so this discovery opens up a lot of new exciting possibilities for us," Dr. Farley said. He added that Phase III of this trial is scheduled to begin in the next few weeks, with that trial to be the "definitive test" before the treatment becomes available to the general population.