PMC8531795_01
The patient's peripheral blood features medium and large-sized cells with scant cytoplasm and irregular nuclear contours (a; 400x magnification). Approximately 70-80% of the cellular elements within his hypercellular bone marrow biopsy show morphologic characteristics similar to those seen in the peripheral blood (b; 400x magnification). The cells are positive for CD20 (c), CD10 (d), and CD5 (e) by immunohistochemistry (400x magnification). Ki-67 demonstrates a high proliferation index of 80% (f; 400x magnification).
CRIHEM2021-2628100.001.jpg
PMC8531795_01_CRIHEM2021-2628100.001.jpg
fig1
His peripheral blood smear was notable for medium and large-sized lymphocytes with irregular nuclear contours accounting for 15% of circulating white blood cells (Figure 1(a)). By immunohistochemistry, the malignant cells were positive for CD20, PAX-5, CD5, CD10, MUM1, and BCL-2, while negative for EBV, CD30, BCL-6, cyclin D1, SOX-11, TdT, and MYC (Figures 1(b)-1(e)).