Apheresis was introduced in the late 1960s and was innovative as it served to remove the major blood cell constituents or plasma rapidly, while efficiently processing large volumes of blood (Kaushansky et al. [63]). The earliest procedures were performed on patients with chronic myeloid leukaemia. In these instances, the procedure served to lower the patient's white cell count (Kaushansky et al. [63]).

With scientific advances, apheresis is no longer only used on patients in order to remove blood components or exchange them for therapeutic purposes; it is now possible to harvest blood components such as stem cells to be used for donation. Stem cells can be ‘mobilized’ into the peripheral blood following treatment with cytotoxic chemotherapy and/or the administration of the haematopoietic growth factor G‐CSF, with or without plerixafor (an immunostimulant). The use of stem cells collected by means of apheresis has superseded bone marrow in many transplant centres (Richardson and Atkinson [98]). Exact protocols vary according to underlying disease, treatment regimens, local practice and the type of stem cell donor; for example, cytotoxic chemotherapy and plerixafor are not used to mobilize stem cells from healthy donors.

Another, newer application of apheresis in the haemato‐oncology setting is extracorporeal photopheresis (ECP) (Knobler et al. [65]). This involves a specialized cell separator machine that additionally incorporates a light box that exposes the patient's collected lymphocyte product to ultraviolet light following the administration of a photo‐sensitizing drug. Indications for use are cutaneous T cell lymphoma, and chronic graft‐versus‐host disease post allogeneic stem cell transplant (Howell et al. [52]).