Introduction
Leukemia cutis (LC) is a cutaneous disease caused by the infiltration of
neoplastic leukocytes into the skin. The cutaneous manifestations of LC
commonly present as patches of homogeneous erythema, papules, and
nodules 1. Only one case showing annular erythema as
LC due to T-cell acute lymphocytic leukemia (T-ALL) has been reported to
date 2. Furthermore, there has been no case showing
annular erythema as LC due to B-cell ALL (B-ALL).
Blinatumomab is an antibody drug that mediates the formation of a
synapse between T-cells presenting the CD3 antigen and tumor cells
presenting the CD19 antigen, resulting in the redirected lysis of
CD19-positive B-ALL cells 3. A phase 2 clinical trial
showed that the number of neoplastic leukocytes (tumor cells) decreased
below the detection limit within a few days and this effect persisted
during the period of blinatumomab treatment 3. This
trial concomitantly demonstrated that the number of cytotoxic T-cells
rapidly decreased within 1 day after the administration of blinatumomab
and recovered above the base number within 1 week, the so-called
redistribution phenomenon 3. Although
immune-modulating drugs, such as blinatumomab, potentially affect the
cutaneous manifestations of LC through cytotoxic T-cells, limited
information is currently available.
We herein report a case of B-ALL-induced LC with the annular appearance
of multiple erythema potentially modified by blinatumomab.