ASCO 2008 Report: Gastrointestinal Cancer

Researchers identify genetic markers for chemotherapy response in colorectal cancer patients and establish gemcitabine as a new standard therapy for patients with resected pancreatic cancer.

KRAS Mutation and Cetuximab Resistance

Several groups examined the KRAS gene mutation as a predictive marker for response to cetuximab (Erbitux), an antibody that targets the epidermal growth factor receptor (EGFr). In an update of the CRYSTAL trial, researchers continued to evaluate the efficacy of the chemotherapy regimen FOLFIRI with or without cetuximab in advanced colorectal cancer patients. As reported at ASCO 2007, patients in the cetuximab arm had 0.9-month longer progression-free survival (PFS) and an 8% higher response rate compared with those who received chemotherapy alone. This year, the authors reported results for patients whose tumors were KRAS wild type (348 patients, 64%) or KRAS mutant (192 patients, 36%; J Clin Oncol 2008…