CD25, TAC

This is the interleukin-2 receptor. Interleukin-2 conjugated to diptheria toxin has been used in the treatment of mycosis fungoides1; this is predicated on demonstration of expression of CD25 by the neoplasm.

Immunohistochemical expression

• activated T cells, B cells and macrophages

• adult T cell ALL associated with HTLV

• hairy cell leukaemia

• some cases of splenic lymphoma with villous lymphocytes

• some peripheral T cell lymphomas

  • some cases of Mycosis Fungoides, particularly in the large cell component or associated with large cell transformation

  • some cases of adult T-cell lymphoma/leukaemia

  • some ALCL

• some peripheral B cell lymphomas

• neoplastic mast cells

• some Hodgkin's disease

Diagnostic utility

• the diagnosis of systemic mastocytosis

References

1Liu V., McKee PH. Cutaneous T-cell lymphoproliferative disorders; approach for the surgical pathologist: recent advances and clarification of confused issues. Advances in Anatomic Pathology 2002;9:79-100..

©SMUHT/PW Bishop