OBJECTIVE Past research that has compared cancer treatment tolerance between elderly and nonelderly cancer patients has been contradictory. Some investigators concluded that there is no difference between the groups, while others demonstrated elderly patients experienced less tolerance to treatment. As a result, some physicians discriminate against elderly cancer patients by not entering them onto clinical trials out of a belief that they will not tolerate the therapy. METHODS An analysis was performed using the Illinois Cancer Center (ICC) data base, which contains treatment information for all patients registered onto phase II trials. A maximum of 672 cases was available for evaluation of 11 treatment-related variables. RESULTS The results demonstrated no significant differences between elderly and nonelderly patients for the following seven treatment-related variables: performance status (PS), number of dose reductions, number of treatment interruptions, total days of delay, best response, reason off-study, and number of grade 3 or greater toxicities. Minor differences were detected for number of courses and number of dose escalations. CONCLUSIONS Based on these results, elderly patients should not be denied access to cancer clinical trials relative to age alone.