Figure 1: Peripheral blood findings in IVLBCL
There was marked normocytic anemia, and red blood cells showed some agglutination (image on the left), marked anisocytosis, increased polychromasia, occasional spherocytes and nucleated forms. Platelets were markedly reduced. Review of the peripheral blood smear shows occasional circulating atypical lymphoid cells. The image on the right shows atypical lymphoid cells are medium to large in size and have irregular nuclei, clumped chromatin and high N/C ratio. A lymphocyte is seen at the bottom for comparison.
Flow cytometry showed a CD19+ CD5+ (partial) lambda restricted mature B-cell clone.
Figure 2: Bone marrow H&E in IVLBCL
The bone marrow core biopsy shows multifocal abnormal lymphoid infiltrate with a prominent sinusoidal infiltrating pattern (at higher power).
Figure 3: CD20 in IVLBCL
CD20 immunostain highlights the atypical sinusoidal infiltrate strongly confirming their B-lineage origin.
Figure 4: BCL2 & MUM1 in IVLBCL
The large B-cells strongly express cytoplasmic BCL2 (image on left) and nuclear MUM1 (image on right). They were additionally also positive for CMYC by IHC (not shown). Despite the EBV viremia, EBV ISH was negative in the marrow.
Figure 5: Aspirate smears in IVLBCL
Scattered large vacuolated lymphoma cells are noted in the image on the left with evidence of hemophagocytic histiocytes noted in both images.
Figure 6: CD31 in IVLBCL
CD31, a vascular endothelial marker highlights the negative large lymphoma cells within the sinusoidal spaces positive for CD31.