Drug Shows Promise for Subset of Stage III Colon Cancer Patients

This article describes the results of a clinical trial—a research study with volunteer patients. The trial tested adding a third drug to a standard two-drug chemotherapy treatment for colorectal cancer. The standard treatment consists of the drugs fluorouracil and leucovorin. It is given to patients after tumor-removal surgery to keep the cancer from coming back (recurrence). In the trial, a third drug called irinotecan was added. The researchers found that stage III patients whose tumors tested positive for a genetic change called CIMP benefitted from the irinotecan addition. Stage III CIMP-negative patients did not.

“When added to the standard chemotherapy treatment — fluorouracil and leucovorin — adjuvant irinotecan therapy improved overall survival rates for patients with the CpG island methylator phenotype (CIMP). CIMP is seen in about 10 to 20 percent of colorectal cancers. Patients with CIMP-negative tumors, however, exhibited significant harm from the addition of irinotecan — overall survival was 68 percent compared with 78 percent for those receiving the standard treatment alone.

“Our results serve as an example that the molecular characterization of individual tumors may help to determine the most appropriate treatment for patients with colon cancer,” said lead study author Stacey Shiovitz, MD, from the department of medicine, University of Washington, Seattle, WA, and the clinical research division of Fred Hutchinson Cancer Research Center, also in Seattle. “Based on our findings, identification of a tumor’s CIMP status should play a greater role in the clinical setting.”


No Difference in Response Rate but Overall Survival Benefit With First-Line FOLFIRI/Cetuximab vs FOLFIRI/Bevacizumab in Metastatic Colorectal Cancer

Editor’s note: Researchers organized a clinical trial with volunteer patients to compare two treatments for people with metastatic colorectal cancer. All patients in the trial took a chemotherapy treatment called FOLFIRI. (FOLFIRI combines the drugs fluorouracil, leucovorin, and irinotecan.) Some of the patients were also given the drug cetuximab, and the rest took the drug bevacizumab along with FOLFIRI. The patients who took FOLFIRI plus cetuximab survived significantly longer than the patients who took FOLFIRI plus bevacizumab.

“In a European phase III FIRE-3 trial reported in The Lancet Oncology, Heinemann et al found no difference in response rate, the primary endpoint, between FOLFIRI (fluorouracil, leucovorin, and irinotecan) plus the anti-EGFR antibody cetuximab (Erbitux) vs FOLFIRI plus the anti-VEGF-A antibody bevacizumab (Avastin) in first-line treatment of patients with metastatic colorectal cancer. The cetuximab-containing regimen was associated with a significant overall survival advantage…

“In this open-label trial, 592 patients with KRAS exon 2 codon 12/13 wild-type metastatic colorectal cancer aged 18 to 75 years from centers in Germany and Austria were randomly assigned between January 2007 and September 2012 to receive FOLFIRI plus either cetuximab (n = 297) or bevacizumab (n = 295). The primary endpoint was objective response in the intention-to-treat population. The study has completed recruitment, but patient follow-up is ongoing.”