Keck School of Medicine cancer specialists shared their research with the world in mid-May, presenting dozens of abstracts on topics ranging from molecularly targeted therapy to cancer vaccines at the American Society of Clinical Oncology annual meeting in Orlando, Fla.
Researchers regularly unveil news-making results from major trials at the yearly international conference, which draws more than 25,000 attendees. USC/Norris Comprehensive Cancer Center and Keck School oncologists contributed to the abundance of research findings in 2005.
For one, Jeffrey Weber, the Lucy and Berle Adams Chair in Cancer Research and the Keck School’s chief of oncology, reported in an oral session on results from a phase II study of a vaccine therapy against advanced melanoma. The trial combined melanoma-related peptides with Montanide ISA 51 (a drug that stimulates the immune system) and different doses of interleukin 12 (IL-12) with alum. Higher doses of IL-12 in the study seemed to boost the body’s response to the melanoma antigens.
Investigators from the lab of gastrointestinal oncologist Heinz-Josef Lenz, associate professor of medicine at the Keck School, authored 16 abstracts.
Among their presentations:
• A new combination of drugs appears to battle advanced stomach cancer better than other platinum-based therapies, while offering patients more convenience and potentially less discomfort, according to Lenz. Researchers studied the combination of a new drug, called S-1, and cisplatin in patients with advanced gastric cancer. “We believe the therapy has the potential to not only fight cancer more effectively, but also is easier for cancer patients to deal with,” Lenz said. S-1 is available in a capsule and contains a component that aims to combat the gastrointestinal discomfort associated with many chemotherapies.
• Cetuximab, also known as Erbitux, can battle cancer and prolong life in many patients with advanced colorectal cancer who have exhausted all other treatments. “Even in people who have gone through six or more previous courses of chemotherapy, cetuximab may fight the growth of cancer, giving patients additional months of life,” said Lenz.
• A unique targeted drug called SU11248 shows promise against hard-to-treat neuroendocrine tumors. The drug was evaluated in a phase II clinical trial for carcinoid tumors and pancreatic islet-cell tumors. About 80 percent of patients saw their disease stabilize (cancer stopped growing), and about 10 percent of those with islet-cell tumors had tumors that actually partially shrank in response to the drug, Lenz said.
• In a promising trial through the National Cancer Institute’s Cancer Therapy Evaluation Program, both bevacizumab—known as Avastin—and cetuximab were given to patients with colorectal cancer who failed irinotecan chemotherapy. “The data are very good—the response rate is significantly better,” said Lenz, who noted that USC/Norris led correlative science efforts in the trial.
Young investigators such as Michael Gordon, Oliver Press, Wu Zhang, Andrew Hendifar, Katrin Rhodes and Daniel Vallböhmer from Lenz’s lab and biostatistician Dongyun Yang also presented studies on topics such as the potential of gene-expression profiling to predict risk of cancer recurrence and the identification of molecular markers that may predict whether patients will respond to cetuximab.
Keck School researchers made their mark in other areas as well.
Parvesh Kumar, professor and chair of the Keck School’s Department of Radiation Oncology, announced results from the phase II trial of an innovative treatment for advanced head-and-neck cancer called RADPLAT.
Kumar reported that about half of patients were still alive four years after the treatment, which combines radiation and a platinum-based chemotherapy drug called cisplatin.
Through RADPLAT, oncologists inject cisplatin through tiny catheters directly into the arteries that feed the tumor, sending the drug exactly where it is needed—and making it less likely to harm healthy parts of the body.
Today, advanced head and neck cancer is difficult to battle, and many patients struggle to maintain their quality of life. Kumar noted that RADPLAT helps patients preserve organ functions, such as speech and swallowing.
The National Cancer Institute funded the study through an RO1 grant; the Radiation Therapy Oncology Group provided biostatistical support.
In another study, Peter Conti, professor of radiology, reported on a way to streamline a new form of treatment for patients with non-Hodgkin’s lymphoma. Called radioimmunotherapy, the treatment allows physicians to target radiation straight to patients’ cancer cells from within the body, rather than through external beams.
Radioimmunotherapy joins radioactive atoms to special antibodies. These antibodies are injected into the body, where they deliver their radioactive payload by seeking out and binding to proteins found on cancer cells.
However, in a few patients, the radioactive antibodies may go to the wrong tissues.
That means that physicians are required to perform numerous imaging scans to monitor patients at the start of therapy to make sure the treatment goes where it should. That lengthens and complicates treatment.
Conti studied about 400 cases in which patients had received the treatment. Among the small minority whose medication went to the wrong site, all cases were apparent through imaging on the very first day of treatment.
That knowledge should enable physicians and patients to confidently proceed with treatment if all appears well 24 hours after the first injection is given.
USC hematologists also presented data on the improved outcome of patients with HIV-related lymphoma in the era of advanced anti-HIV therapies, while USC pathologists provided results of a study on alterations in the p53 gene and risk of recurrence of bladder cancer.