The percentage of chemotherapy treatments resulting in death by 28 days for a given toxicity grade. For each toxicity grade, the number of patients who died within 28 days of initiating treatment divided by the number of patients with that toxicity grade is shown below the graph. P values were calculated by Fisher exact test, and divided by one third to account for multiple comparisons for each toxicity. *P < .05, **P < .005, ***P < .0005.