Buckminsterfullerene ( colloquially known as C6o or the buckyball) is an all carbon compound that may have utility in various age-related diseases as an antioxidant or delivery vector for pharmaceutical compounds. Previous studies have suggested that C6o may have antineoplastic effects, but antioxidant administration has also been reported to exacerbate human cancers. To further elucidate the effects of C60 on human cancers, we conducted a pilot study to evaluate C6o in a xenograft model of acute myelogenous leukemia. KG-la, a human cell line of acute myelogenous leukemia, was administered to five groups of NOD.Cg-Prkdcscid Il2rg""1Sug/JicTac mice, ranging from 6 to 15 weeks old. Following a loading dose, each group received weekly intraperitoneal injections of saline, olive oil, or three varying doses of C6o, respectively. Parameters evaluated during the study included body mass, complete blood counts, liver enzyme values, presence of KG-la in peripheral blood, and mortality. Body mass, complete blood counts, and liver enzymes remained stable or within expected limits. The presence of KG-la in peripheral blood, as determined by flow cytometry, proved to be an umeliable screening method. There was no statistically significant difference between the groups, suggesting C6o does not promote leukemia proliferation in this model. Notably, C6o-treated animals showed a dose dependent delay in all-cause mortality, supporting broader testing of C6o as an anticancer therapeutic or chemotherapy adjuvant.