Previously, Dr Richard Goldberg and colleagues from North Carolina reported results of Intergroup N9741.
This study compared a combination of treatments for patients with untreated metastatic colorectal cancer.
The team compared standard bolus fluorouracil, leucovorin, plus irinotecan with infused fluorouracil, leucovorin, plus oxaliplatin, and irinotecan plus oxaliplatin.
High rates of grade 3 toxicity on leucovorin, plus irinotecan led the team to reduce the starting doses of both irinotecan and fluorouracil by 20%.
The current study compares leucovorin, plus irinotecan with infused fluorouracil, leucovorin, plus oxaliplatin.
The primary comparison was time to progression, with secondary end points of response rate, overall survival, and toxicity.
| Toxicity profiles were not different between regimens for nausea|
|Journal of Clinical Oncology|
The team of doctors randomly assigned 305 patients.
The North Central Cancer Treatment Group Data Safety Monitoring Committee interrupted enrollment when outcomes crossed predetermined stopping boundaries.
The doctors found that results were superior for infused fluorouracil, leucovorin, plus oxaliplatin compared with leucovorin, plus irinotecan for time to progression.
The results were also improved for response rate, and overall survival with infused fluorouracil, leucovorin, plus oxaliplatin.
Toxicity profiles were not different between regimens for nausea, vomiting, diarrhea, febrile neutropenia, dehydration, or 60-day all-cause mortality.
The doctors noted that sensory neuropathy and neutropenia were significantly more common with infused fluorouracil, leucovorin, plus oxaliplatin.
Approximately 75% of patients in both arms received second-line therapy.
The team reported that 58% of leucovorin, plus irinotecan patients received oxaliplatin-based second-line therapy.
About 55% of infused fluorouracil, leucovorin, plus oxaliplatin patients received irinotecan-based regimens as second-line therapy.
Dr Goldberg's team commented, “Infused fluorouracil, leucovorin, plus oxaliplatin led to superior response rate, time to progression, and overall survival compared with leucovorin, plus irinotecan.”
“The survival benefit for infused fluorouracil, leucovorin, plus oxaliplatin observed in the earlier stage of the study was preserved with equal use of either irinotecan or oxaliplatin as second-line therapy.”