“Younger patients experienced less leukopenia and stomatitis, but more frequent nausea/vomiting,” the authors add.
In the background to their paper, Dr. Daniel Sargent, with the Mayo Clinic in Rochester, Minnesota, and colleagues note that when adjusted for stage, survival of younger patients with colorectal cancer is at least as good as in older patients. However, the benefits and toxicities of adjuvant chemotherapy in young adults are unclear.
To investigate, the team analyzed data pooled from 24 randomized trials of adjuvant therapy involving a total of 33,574 colon cancer patients, more than 99% of whom had stage II or III disease. The dataset included 1758 patients younger than 40 years and 5817 younger than 50.
The recurrence free interval was no different in patients younger than 40 compared to those older than 40 (hazard ratio 1.0) or in patients younger than 50 compared to older patients (HR 1.02), the researchers found.
Younger patients had better disease-free survival and overall survival than older patients, according to the report. For example, using 50 years as the cutoff, 5-year disease-free survival rates were 67.3% versus 63.4% in younger versus older patients (HR 1.19; p<0.001).. Corresponding rates of 5-year overall survival were 75.5% versus 70.5% (HR 1.33; p<0.01).
Regarding the occurrence of adverse events grade 3 or higher, the team found that younger patients tolerated therapy as well, if not better, than older patients, with the exception of nausea and vomiting, They suggest more aggressive antiemetic regimens may be warranted in younger adults.
Dr. Sargent and colleagues conclude, “Patients younger than 50 years with stage II and III colon cancer enrolled onto clinical trials had similar benefits from adjuvant therapy as older patients.”
They add, “It has been recognized that this population is less likely to be insured and use medical resources, leading to a delay in diagnosis. The potential for high survival with stage II and III colon cancer stresses the importance of early recognition and appropriate treatment of this population.”