CD34 and cancer: The presence of CHIP was associated with a history of smoking (p = 0.04), past medical history of cancer (p = 0.04) and a decreased efficiency of stem cell mobilization (5.8 million CD34+ cells/kg/day in those with CHIP compared to 8.3 million CD34+ cells/kg/day in those without CHIP (p = 0.03) (Table 1).