This identical morphology makes it difficult to differentiate CD30-positive transformed MF (CD30+ TMF) from cutaneous anaplastic large cell lymphoma (cALCL), which belongs to the CD30+ lymphoproliferative disorders (CD30+ LPDs) subgroup of CTCL and has a more favorable 5-year survival rate exceeding 80% (1, 7). The gene discussed is TNFRSF8; the disease is primary cutaneous T-cell non-Hodgkin lymphoma.