Abstract: Objective To evaluate the profile of proliferating T cells and dendritic cells (DCs) in the skin infiltrates of patients with mycosis fungoides (MF) in different stages. Method Paraffin section and immunohistochemisty with monoclonal antibody were used to detect the expression of special antigen per section. Results The numbers of Ki-67⁺ cells and cutaneous lymphocyte-associated antigen (CLA⁺) cells both increased significantly in the skin infiltrates of MF. Most Ki-67⁺ cells expressed both CLA and CD4 antigen. The number of Ki-67⁺ cells was significantly higher (P<0.01) in the skin infiltrates in tumor stage than that in plaque stage, and most of the cells were irregular in shape with obvious heteromorphism. No CD83⁺/Ki-67⁺ DC was observed. However, the DCs were always surrounded by Ki-67⁺ cells, and CD83⁺ DCs were closely contacted with Ki-67⁺ cells. Conclusion The number and immunopathologic feature of CLA⁺/Ki-67⁺ cells in the skin infiltrates of MF may have important diagnostic value for the early diagnosis and evaluation of prognosis of MF.

Key words: Lymphoma, T-cell, cutaneous, Dendritic cells, K. i-67 antigen, T-lymphocytes, CLA