Abstract: To study the clinical application of molecular diagnosis in cutaneous T-cell lymphoma (CTCL),the polymerase chain reaction Was used to detect the rearrangements of T-cell receptor (TCR)gene in 60 patients with cutaneous lymphocytic infiltrates.The result showed that dominant clonal TCR-β or γ gene rearrangements were detected in 36/40 CTCL,4/6 suspected mycosis fungoldes/Sézary syndrome,1/1 lymphomatoid papulosis.No dominant clonal TCR-β or γ gene rearrangements were detected in 2 patients with CBCL,1 patient with lymphocytoma cutis,8 patient with benign lymphocytic infiltrates of skin and 2 normal controls.This study demonstrates that the method is helpful for the lineage determination,clonality and early diagnosis of CTCL.

Key words: Cutaneous T-cell Lymphoma, T-cell receptor, PCR