FREQUENCY AND PROGNOSTIC-SIGNIFICANCE OF CLONAL T-CELL RECEPTOR BETA-GENE REARRANGEMENTS IN THE PERIPHERAL-BLOOD OF PATIENTS WITH MYCOSIS-FUNGOIDES

Background.-Previous studies have shown that peripheral blood involvement is a poor prognostic sign in patients with cutaneous T-cell lymphoma. However, evaluation of the results of these studies is difficult. In this study peripheral blood mononuclear cells from 45 patients with various stages of mycosis fungoides (MF) were investigated for the presence of clonal T-cell populations by T-cell receptor beta (TCRbeta)-gene rearrangement analysis. Results.-Clonal TCRbeta-gene rearrangements were found in five (11%) of 45 patients with MF, including one (3%) of 31 patients without MF and four (27%) of 15 patients with histologically confirmed lymph node involvement. With respect to skin stage, clonal T-cell populations were detected in one (4%) of 23 patients with plaque stage disease, two (10%) of 19 patients with tumor stage disease, and two (50%) of four patients with erythrodermic MF. In the group of patients with lymph node involvement the median survival of patients with detectable clonal T-cell rearrangements in the peripheral blood was much shorter (3 months) than that of patients without clonal rearrangements (16 months). Conclusions.-The results of this study indicate that clonal TCRbeta-gene rearrangements, as detected by Southern blot analysis, are uncommon in the peripheral blood of patients with MF, in particular in patients without histologically documented lymph node involvement. The presence of clonal T-cell populations in the peripheral blood of MF patients with lymph node involvement is usually associated with rapidly fatal disease.