Colorectal cancer is one of the most common and deadly cancers worldwide, and treatment decisions for older patients remain highly debated. Now, researchers have found that oxaliplatin-based chemotherapy significantly improves survival only in stage III colorectal cancer patients aged 70 or younger.
For patients over 70, the drug offered no survival advantage and led to higher rates of treatment discontinuation due to toxicity. Importantly, stage II patients showed no survival benefit at any age.
Dr. Jun Woo Bong from Korea University Guro Hospital, with Dr. Hwamin Lee, and Dr. Seogsong Jeong from Korea University College of Medicine, conducted a large-scale population study, which was made available online on August 6, 2025, in JAMA Network Open.
The team examined health records from more than 8,500 patients with stage II or III colorectal cancer who underwent surgery followed by chemotherapy between 2014 and 2016. Patients were divided into two groups: those treated with oxaliplatin-based combinations, and those given standard chemotherapy alone. Using advanced statistical methods, the researchers systematically tested whether an age threshold existed at which oxaliplatin stopped providing survival benefits.
The results were decisive. In stage III patients aged 70 or younger, oxaliplatin reduced the risk of death by 41%, boosting five-year survival from 78% to nearly 85%. But in those older than 70, oxaliplatin did not improve survival and was linked to higher rates of treatment discontinuation. In fact, almost 40% of older patients receiving oxaliplatin stopped chemotherapy early, often due to toxicity. For stage II patients of any age, oxaliplatin showed no added survival benefit.
Avoiding ineffective chemotherapy in older patients may help reduce costs, complications, and hospitalizations. Health systems could redirect resources to therapies and supportive care that make a greater difference in survival and quality of life. The research also sets the stage for longer-term changes in global cancer care.
