PMC6165590_01
(a) The lymph node shows a completely effaced architecture. The sinus system is open and filled with partly pleomorphic histiocytic cells (x50, hematoxylin and eosin stain (H&E)). (b) The partly pleomorphic histiocytic cells are present in the sinuses, while the intervening cords exhibit a marked plasmacytosis (x200, H&E). (c) The histiocytic cells express CD68 (x200). (d) The histiocytic cells show nuclear and cytoplasmic positivity for S100 (x200). (e) The mature plasma cells (Marschalko type) present in the intervening cords (x630, H&E). (f) Monomorphic expression of light kappa chain in plasma cells (x630). (g) Monomorphic expression of IgM in plasma cells (x630). (h) Expression of MUM1 in plasma cells (x630). (i) Ki-67 is expressed in 5-7% of the cells of the sinuses and up to 50% of cells within the intervening cords of the lymph node (x200).
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fig1
Histologic examination of the right axillary lymph node revealed a completely effaced architecture (Figure 1(a)). The sinus system was open and filled with pleomorphic histiocytic cells, some of which showed emperipolesis of peripheral blood cells (Figure 1(b)). Immunohistochemical staining showed the expression of CD68 (Figure 1(c)) and CD163 in these histiocytic cells accompanied by coexpression of S100 (Figure 1(d)), while the staining result was negative for CD1a and Langerin. The lymph node tissue showed an infiltrate consisting of partly nodular and partly diffused pattern of CD20-positive and CD10-negative B-lymphocytes and extensive plasma cell infiltration (Figure 1(e)). The plasma cells showed positive staining for light kappa chain (Figure 1(f)), IgM heavy chain (Figure 1(g)), and MUM1 (Figure 1(h)). Ki-67, a marker of cell proliferation, was expressed in 5-7% of the cells of the sinuses and up to 50% of the cells within the intervening cords of the lymph node (Figure 1(i)).
Left-sided peripheral facial nerve palsy with an inability to wrinkle the forehead and nose, unequal lid fissures, and inability to lift the corner of the mouth.
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Soon, peripheral paralysis of the facial nerve occurred (Figure 2).
(a) The focus of large lymphoid cells, surrounded by necrotic tissue (x400, H&E). B-F. Immunostaining of the large tumor cells expressing CD20. (b) (x400), CD30 (c) (x400), light kappa chain. (d) (x200), IgM. (e) (x200), MUM1. (f) (x400). (g) Detection of EBV-positive large lymphocytes using EBER in situ hybridization.
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Large tumor cells were also present as perivascular and perineural clusters (Figure 3(a)). Large lymphoid cells expressed CD20 (Figure 3(b)), CD79alpha, CD30 (Figure 3(c)), light kappa chain (Figure 3(d)), IgM heavy chain (Figure 3(e)), PAX5, and MUM1 (Figure 3(f)). EBER-ISH demonstrated the presence of EBV-positive large lymphocytes (Figure 3(g)). EBV-positive diffuse large B-cell lymphoma, not otherwise specified (DLBCL, NOS) was diagnosed.
B-cell clonality analysis with IGHV FR1-IGHJ (Tube A), IGHV FR2-IGHJ (Tube B), and IGHV FR3-IGHJ (Tube C). PCR products demonstrate an identical clonal pattern between the NMZL and DLBCL.
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Tube B, and Tube C) were used to detect Vh-Jh rearrangements. Identical clonal patterns between the NMZL and DLBCL were demonstrated (Figure 4). The resulting condition was considered a transformation of NMZL into an EBV-positive DLBCL, NOS.