According to results recently presented at the 38th annual meeting of the American Society of Clinical Oncology (ASCO), the chemotherapy regimen consisting of oxaliplatin, 5-FU (fluorouracil) and leucovorin improves survival compared to other standard chemotherapy combinations for the treatment of advanced colorectal cancer.
Colorectal cancer affects the colon and rectum, parts of the body's digestive system that together form a long, muscular tube called the large intestine. The colon consists of the first 6 feet of the large intestine and the rectum is the last 8-10 inches. Colorectal cancer is the second leading cause of cancer mortality in the United States and Europe, and accounts for 15% of new cancer cases each year. Advanced colorectal cancer refers to cancer that has spread from its site of origin to distant sites in the body. Currently, the standard chemotherapy regimen for patients with stage IV colorectal cancer is Camptosar® (irinotecan or CPT-11), 5-FU and leucovorin (LV). However, since most patients with advanced colorectal cancer are not considered curable, researchers are evaluating novel therapeutic regimens or chemotherapy combinations for the treatment of this disease in order to improve survival.
Researchers from the North Central Cancer Treatment Group (NCCTG) conducted a clinical trial comparing three different chemotherapy combinations as initial therapy for patients with advanced colorectal cancer and presented the results at ASCO. The treatment regimen consisting of oxaliplatin, a chemotherapy agent not yet approved in the United States, plus 5-FU/LV was compared toCamptosar®/5-FU/LV or Camptosar®/oxaliplatin. Patients were allowed to “cross over” and receive a different chemotherapy combination than what they initially received if their cancer progressed. Results were presented from 267 patients treated with oxaliplatin/5-FU/LV and 264 patients treated with the standard regimen, Camptosar®/5-FU/LV.
Time to cancer progression was approximately 8.8 months for patients treated with oxaliplatin/5-FU/LV, compared to 6.9 months for patients treated with Camptosar®/5-FU/LV. The average survival for patients treated with oxaliplatin/5-FU/LV was significantly improved to 18.6 months, compared to 14.1 months for patients treated with Camptosar®/5-FU/LV and one year following treatment, 71% of patients treated with oxaliplatin/5-FU/LV survived, compared to only 58% for patients treated with Camptosar®/5-FU/LV. Importantly, patients reported fewer severe side effects when treated with oxaliplatin/5-FU/LV than with Camptosar®/5-FU/LV.
The United States Food and Drug Administration (FDA) denied approval of oxaliplatin based on previous trial results and requested the submission of more data. However, results from this trial clearly suggest superiority over standard regimens and the FDA review process of oxaliplatin for treatment of colorectal cancer is underway. Since oxaliplatin has not yet been approved by the FDA in the United States, the National Cancer Institute (NCI) and other participating institutions will provide access to oxaliplatin in the U.S. through the Treatment Referral Center (TRC) protocol. In addition, if eligible patients cannot receive oxaliplatin on the TRC protocol due to limited drug supply for the next several months, the NCI has established a random lottery system through which 300 patients will be randomly selected every month for treatment with oxaliplatin. Patients with advanced colorectal cancer may wish to speak with their physician about the risks and benefits of participation in a clinical trial evaluating oxaliplatin/5-FU/LV or call 1-800-4-CANCER for more information.
Reference: Goldberg R, Morton R, Sargent C, et al. N9741: oxaliplatin (oxal) or CPT-11 + 5-fluorouracil (5FU)/leucovorin (LV) or oxal + CPT-11 in advanced colorectal cancer (CRC). Initial toxicity and response data from a GI Intergroup study. Proceedings from the 38th annual meeting of the American Society of Clinical Oncology. 2002;21 (Abstract 511).
Goldberg RM, Oral presentation at the 38th annual meeting of the American Society of Clinical Oncology, Orlando, Florida. Saturday, May 18, 2002.