Cerebrospinal fluid involvement in acute promyelocytic leukaemia at presentation.

In acute promyelocytic leukaemia (APL), extramedullary disease (EMD) is rare but can occur in those who relapse following therapy. Although the most common site of EMD in APL is central nervous system (CNS) and skin, CNS involvement in recently diagnosed patients with APL is very rare and rarely described. We report cerebrospinal fluid involvement in a case of APL, on day 3 of induction therapy. 2015 BMJ Publishing Group Ltd.