CHAPEL HILL, N.C. - More than 57,000 Americans face a diagnosis of kidney cancer each year. Now patients with advanced disease may soon have another treatment option. Physicians who conducted a pilot study at UNC Lineberger Comprehensive Cancer Center found that therapy before surgery with the drug sorafenib can reduce the size of large tumors and could be safely administered without adding significantly to the risks of surgery.
Their results are published in the February 16 online issue of the Journal of Clinical Oncology.
Kimryn Rathmell, MD, PhD, a UNC Lineberger physician-scientist, is the study’s principal investigator. “We found that primary kidney tumors responded to this therapy, shrinking up to 40 percent prior to surgery. What this means for kidney cancer patients is that their surgery may be less extensive and, we hope, can provide a better outcome for patients because of tumor shrinkage,” she says. Rathmell is an assistant professor of medicine at UNC-Chapel Hill.
At present, removal of the primary tumor (often with the kidney as well) is the standard treatment for patients with kidney cancer, whether the disease is localized to the kidney or has spread to distant sites. This broad spectrum includes patients with very large tumors that may not be ideal for surgical removal as well as patients who may benefit from early systemic interventions, but who would also benefit from removing the kidney later. This study addressed the question of whether systemic therapy, and in particular, therapy that targets the process by which tumors seek and find new blood vessels to fuel their growth, can benefit patients before they undergo surgery to remove tumors.
The study was conducted to evaluate the safety and feasibility of preoperative treatment using sorafenib (Nexavar®) in 30 patients with stage two or higher kidney cancer including metastatic disease. Patients received their treatment at UNC Lineberger Comprehensive Cancer Center and at Rex Cancer Center in Raleigh. They took two daily oral doses of the drug for between four to eight weeks prior to surgery.
Nexavar, manufactured by Bayer, is a targeted drug used to treat advanced kidney cancer and a type of liver cancer. Nexavar prevents the growth of new blood vessels that fuel tumor growth. Sorafenib is one among the class of new targeted agents approved by the FDA in 2005 for evidence of benefit for patients with metastatic kidney cancer.
Two previous studies had been conducted using similar targeted therapy drugs, Sutent and Avastin, but Rathmell’s study is the largest to evaluate the use of Nexavar alone, and the first to explore the possibility that pre-operative treatment might benefit patients who do not have metastatic disease.
Study co-author Matthew Nielsen, MD, assistant professor of surgery in the UNC School of Medicine and a member of the UNC Lineberger urologic cancer program, notes, “This study is a major contribution to the field, demonstrating that Nexavar, is well-tolerated for pre-surgery use, with no increase in the rates of complications or difficulties recovering from surgical removal of the kidney. We are optimistic that this and future similar studies will ultimately allow us to offer, individualized treatment strategies for patients with this common and dangerous disease.”
Another important aspect of this study is the successful integration of systemic therapy with what is traditionally a surgical stage of the disease. According to Nielsen, "This study highlights the value of the team approach to urologic cancer management and exemplifies the need for well-coordinated multidisciplinary oncology services in advancing new forms of treatment."
Rathmell concludes, “This study is promising. We saw significant reduction in the size of tumors using this drug, reducing the extent of surgery and making patient recovery less challenging. A larger study needs to be conducted to determine if preoperative systemic therapy improves outcomes in patients undergoing surgery for kidney cancer.”
Rathmell serves on an advisory board for and has received research funding to conduct clinical aspects of this study from Bayer/Onyx, the manufacturer of sorafenib.