Cancer research updates from the American Society of Clinical Oncology's annual symposium on gastrointestinal cancers.
The American Society of Clinical Oncology (ASCO) hosted its annual symposium on gastrointestinal cancers in January, bringing together more than 3,000 researchers, oncologists and industry professionals to report on the latest advances.
Pancreatic cancer is an aggressive, hard-to-treat disease, especially once it spreads outside the pancreas. Unfortunately, about 80 percent of pancreatic tumors are advanced when diagnosed. Because of the nature of the disease, even small gains are cause to take notice.
At the 2013 Gastrointestinal Cancers Symposium, results of the MPACT study, a phase 3 international trial, found that Abraxane (albumin bound-paclitaxel) and gemcitabine extended overall survival by more than seven weeks when compared with gemcitabine alone.
The study included 842 patients with previously untreated metastatic pancreatic cancer. Researchers found adding Abraxane increased median overall survival from 6.7 months to 8.5 months, meaning half of the patients in the combination arm were alive at 8.5 months. The benefit of the Abraxane combination over gemcitabine alone also increased over time, more than doubling the survival rate at two years. Daniel Von Hoff, oncologist and director of translational research at Translational Genomics Research Institute in Phoenix, Ariz., presented the results and predicted the combination could become a backbone in new regimens for advanced pancreatic cancer.
It’s a challenging task in pancreatic cancer, but we absolutely have to do it.
Andrew Ko, an oncologist who specializes in gastrointestinal cancers at the Helen Diller Family Comprehensive Cancer Center in San Francisco, says he is pleased with the positive results as the drug offers an additional option for patients with advanced pancreatic cancer. He expects Abraxane to gain widespread use for this disease indication; many oncologists, in fact, have already started using the drug, based on an earlier phase trial showing very promising results. Ko says the next step would most likely be looking for biomarkers to predict who would benefit most from this combination. “It’s a challenging task in pancreatic cancer, but we absolutely have to do it.”
Although side effects were seen with the combination, including fatigue, neutropenia and neuropathy, the combination was welltolerated. The drug will most likely be submitted to the Food and Drug Administration by mid-year. Abraxane is approved for advanced non-small cell lung and breast cancers.
In a study conducted in Japan, researchers found that S-1, a drug similar to 5-FU (fluorouracil), was superior to gemcitabine. Nearly 400 patients with non-metastatic disease were randomized to receive gemcitabine or S-1 within 10 weeks of surgery. After two years, 70 percent of patients in the S-1 arm were alive compared with 53 percent in the gemcitabine arm. Recurrence-free survival was also better in the S-1 arm: 23.2 months compared with 11.2 months.
Both drugs were well-tolerated, although there were more cases of diarrhea, anorexia and mouth sores with S-1. Because of metabolic differences in Asian and Caucasian patients, some gastric side effects are more severe among Caucasians, requiring a lower dose. The drug is not yet approved for use in the U.S., but it is prescribed in Japan to treat colorectal, biliary, head and neck, metastatic breast, non-small cell lung, pancreatic and stomach cancers.