CD34 and non-Hodgkin lymphoma: Ketheesan et al. showed that the proportion of CD34+ cells in frozen cord blood did not change after freezing [33], while Lanza et al. demonstrated that 90-day cryopreserved PBMCs derived from patients with non-Hodgkin’s lymphoma had an increase in CD34+ cells compared to fresh samples, attributed to a decrease in mature myeloid cells [34].