A team from New York, USA, determined the association between adjuvant 5-fluorouracil (5-FU)-based chemotherapy and survival in older patients with node-positive colon cancer.
A total of 4768 patients, 65 years of age or older, who received a diagnosis of node-positive colon cancer from 1992 to 1996, were included in the study.
The researchers measured propensity scores to control for known predictors of receiving treatment.
Cox proportional hazards models were used to assess the association of 5-FU therapy with survival.
In addition, sensitivity analyses were used to estimate the possible effects of unknown confounders.
| Hazard ratio for death associated with 5-FU therapy: 0.66.
| Annals of Internal Medicine |
Of the patients included in the trial, 52% received 5-FU therapy.
For this sample, the hazard ratio for death associated with 5-FU therapy was found to be 0.66.
The authors noted that confounding could have accounted for this association only if an unmeasured confounder was extremely unequally distributed between the treated and untreated groups. The other possibility was if a confounder increased mortality by at least 50%.
Dr Vijaya Sundararajan, of the Columbia University, New York, said on behalf of the group, "5-fluorouracil adjuvant therapy is significantly associated with reduced mortality in older patients, similar to the association found in randomized, controlled trials among younger patients."
"More frequent use of 5-FU therapy in older patients would probably reduce death from colon cancer," it was concluded.