TSPO and myeloid sarcoma: Upregulation of TSPO is seen in many CNS diseases, including Alzheimer's, (Edison et al, 2008; Yasuno et al, 2008) Huntington's, (Meßmer & Reynolds, 1998) brain tumours, (Vlodavsky & Soustiel, 2007) traumatic brain injury, (Papadopoulos & Lecanu, 2009) ischaemic stroke, (Cosenza-Nashat et al, 2009; Gerhard et al, 2005) frontotemporal dementia, (Cagnin et al, 2004) amyotrophic lateral sclerosis, (Turner et al, 2004) Parkinson's (Ouchi et al, 2005) and multiple sclerosis (MS) (Versijpt et al, 2005; Vowinckel et al, 1997).