[1] Univ Cambridge, Dept Pathol, Cambridge CB2 1QP, England
[2] Univ Oxford, Nuffield Dept Clin Lab Sci, Leukaemia Res Fund Immunodiagnost Unit, Oxford, England
[3] Addenbrookes Hosp, Dept Histopathol, Cambridge CB2 2QQ, England
[4] UCL Adv Diagnost, London, England