The spleen image shows monotonous proliferation of medium-sized lymphocytes with pale cytoplasm infiltrating dilated splenic sinuses (A, hematoxylin and eosin, 100x; B, hematoxylin and eosin, 400x). The cells are strongly positive for CD3 (C), CD7 (D), TCR gamma/delta (E), and negative for CD5 (F) (C-F, immunohistochemistry with hematoxylin counterstain, 200x).

The bone marrow aspirate smear shows intermediate-size lymphocytes with hyperchromatic nuclei, distinct nucleoli, and scant to moderate cytoplasm devoid of granules (G, Wright-Giemsa, 1,000x). The bone marrow biopsy shows normocellular marrow and a subtle lymphoid infiltrate (H, hematoxylin and eosin, 200x). Immunohistochemistry for CD3 highlights lymphocytes in the expanding sinuses (I, immunohistochemistry with hematoxylin counterstain, 200x).