• computed tomograph;
  • intracerebellar tumour;
  • surface markers;
  • T-cell chronic lymphocytic leukaemia

A case of T-cell chronic lymphocytic leukaemia is described. Intracerebellar tumour was demonstrated by the characteristic feature of contrast-enhanced computerized tomography and was evidenced by surgical procedure. Histological examination revealed lymphocyte infiltration in the cerebellum. Initially, the majority of leukaemic cells were mature, medium-sized lymphocytes with surface marker phenotype of E+, OKT3+, OKT4+, OKT6−, OKT8−. In the terminal stage, large atypical lymphocytes which were morphologically distinct from the original lymphocytes and had different surface marker phenotype of E+, OKT3+, OKT4−, OKT6−, OKT8+, Leu7+ became increasingly prominent. The remaining medium-sized lymphocytes were morphologically and immunologically unchanged. Subsequently, the disease developed to a more aggressive pattern and the patient died in spite of chemotherapy.