Keywords: CD25; CLS, capillary leak syndrome; CR, complete remission; CTCL, cutaneous T-cell lymphoma; DD, denileukin diftitox; E7777; Treg, T-regulatory cell; complete remission; denileukin diftitox; pcALCL, primary cutaneous anaplastic large-cell lymphoma; primary cutaneous anaplastic large-cell lymphoma.