Background:
The presence of a significant percentage of circulating atypical lymphocytes in peripheral blood has already been demonstrated in systemic cd30+ anaplastic large cell lymphoma (alcl), which implies that a leukaemic component may be present in this subset of lymphomas. however, no similar data are available for the cutaneous counterpart of this particular lymphoproliferation.
Objectives:
To assess the presence of atypical cells, cd30+ lymphocytes and of a dominant t-cell clone in peripheral blood in a series of patients with cutaneous cd30+ alcl.
Materials and methods:
Nine patients with either primary (four) or secondary (five) cutaneous cd4+ cd30+ alcl were selected. the percentage of cd30+ cd4+ lymphocytes among peripheral blood mononuclear cells (pbmc) was determined by flow cytometry and the presence of a dominant circulating t-cell clone was assessed by polymerase chain reaction targeting the t-cell receptor gamma chain. a control group composed of apparently healthy individuals was similarly studied at the same time.
Results:
The mean percentage of cd30+ cells in pbmc was slightly higher in patients than in controls (3.9% vs. 2.7%) but the difference was not statistically significant. only two patients displayed more than 5% cd30+ cells, both of whom had a minor tumour burden. a dominant circulating t-cell clone was detected in only three cases, including these two latter patients.
Conclusions:
The occurrence of a significant percentage of cd30+ cd4+ circulating cells is rare in active cutaneous cd30+ alcl, either primary or secondary. this percentage is not related to the apparent skin tumour burden but a significant figure appeared to be correlated with the detection of a dominant t-cell clone in peripheral blood. overall, these data show that, unlike mycosis fungoides, peripheral blood involvement seems infrequent in cutaneous cd30+ alcl. the hypothesis that a high percentage of cd30+ circulating cells might be related to the presence of a cryptic systemic disease cannot be ruled out.