DNA content of mycosis fungoides cells.

DNA content of mycosis infiltrate cells was measured in 5 patients with the Feulgen cytophotometric method in the plaque and tumor stages. In addition, the infiltrate cells were differentiated cytochemically into histiocytes and atypical lymphoid cells with NaF-sensitive naphthol-AS-D-acetate esterase. In no case was an aneuploid stem line demonstrated. However, increasing duration of the tumor stage was associated with a larger proportion of tetraploid and octoploid cells. The DNA histograms also exhibited a local proliferation of atypical lymphoid cells. This proliferation was arrested by cytostatic therapy. Comparison with semi-thin-sections of tumor tissue showed that the mycosis fungoides cells are atypical lymphoid cells. These DNA measurements do not contradict the concept of limited aneuploidy, as reported in cytogenic studies. Thus mycosis fungoides fits in with the DNA distribution pattern in the group of lymphomas.