A 52-year-old man with cutaneous T-cell lymphoma presented with Sezary syndrome-like features including exfoliative erythroderma, lymphadenopathy and leukaemic change without the presence of Sezary cells. Southern blot hybridization analysis revealed T-cell receptor beta-chain gene rearrangements, both in the peripheral blood and in the lymph node. Atypical large cells with convoluted nuclei (Sezary-like cells) first appeared during combined chemotherapy. Although Sezary syndrome is characterized by its particular manifestations and the presence of Sezary cells in the peripheral blood, the clinical significance of Sezary cells has been questioned. It still needs to be decided whether or not the Sezary cell is malignant.