Long-term complications include secondary autoimmune diseases, which are reported in 2-18% of cases, with differences across regimens (higher risk for the use of ex vivo CD34+ cells selection or alemtuzumab) [228, 229]; infertility and secondary amenorrhea, with higher risk for females aged >35 years-old [230, 231]; and the risk for secondary neoplasms, although the causal relationship in this latter case is not conclusive due to the small number of incident cancers observed and the potential contribution of previous treatments [232]. This evidence concerns the gene CD34 and cancer.