Abstract
Prolymhocytic leukemia (PLL) is a rare subtype of lymphocytic leukemias and its cells are immature lymphocytes. It is divided into 2 subgroups: T-PLL and B-PLL according to the lymphocytic origin of the cells. Discriminating B-PLL from other diseases with clinically-similar features is important because of the different treatment approaches and follow-up programs. Hereby, we report a 80-year-old woman presenting with fatigue, leucocytosis and mild anemia. Her peripheral blood smear evaluation revealed 85% prolymphocytes with moderately condensed nuclear chromatin, prominent nucleoli, and a faintly basophilic cytoplasm. Positron emission tomography-computed tomography showed mediastinal lymph nodes with cervical lymph nodes. There was no pathological FDG involvement in the spleen. Bone marrow aspiration smear exhibit atypical wide lymphocytes with prominent nucleoli and abundant agranular cytoplasm. Flow cytometry analysis revealed positive CD5(+), CD19(+), CD20(+), CD22(+), CD11c(+), CD25(+), CD79a(+) and CD79b(+). Fluorescence in situ hybridization technique analysis reveals no t(11;14). Bone marrow biopsy revealed interstitially distributed atypical cells with wide nucleus and prominent nucleolus.