Blood and lymph node T lymphocytes in cutaneous T cell lymphoma: Evaluation by light microscopy

Cytology of peripheral blood and lymph node lymphocytes from a group of unselected patients with cutaneous T cell lymphoma (CTCL) was studied by light microscopy. Twenty of 45 patients had circulating lymphocytes with convoluted nuclei recognized in routine Wright-Giemsa-stained peripheral blood smears. Cytocentrifuge preparations of E-rosetted lymphocytes showed that >10% of the T cells had convoluted nuclei in each of 16 patients with positive blood smears and in six of 17 whose blood smears were negative or inconclusive. Peripheral blood involvement with >10% convoluted T cells was most frequent in patients with erythroderma (100%) including those with normal or decreased lymphocyte counts, and was not uncommon in patients with mycosis fungoides in the plaque or tumor phase (42%). The light-microscopic morphology of the abnormal cells found in the patients with the plaque or tumor phase of mycosis fungoides was not distinguishable from that of the erythrodermic patients. Increased percentages (>15%) of T cells having convoluted nuclei were also found in the lymph node cell suspensions from CTCL patients with adenopathy (18 of 25 patients). These results suggest that a high frequency of extracutaneous involvement occurs in patients with CTCL, the clinical significance of which remains to be determined.