8) This study revealed the tumor cells are macrophages ultrastructurally, and that they express epitopes detected by antibodies to CD68, HAM56, and vimentin, but not with antibodies to cytokeratins, epithelial membrane antigen, S100, HMB-45, leukocyte common antigen
, CD34, desmin, or smooth muscle actin.
4) In our case, we observed membranous positivity for leukocyte common antigen
in the histiocytes that infiltrated the salivary gland, which in our opinion can be regarded as additional evidence that these cells originate from bone marrow-derived monocytes or macrophages.
Lymphoepithelioma-like carcinoma tumor cells are immunoreactive to cytokeratin and epithelial membrane antigen and are negative for leukocyte common antigen, confirming their epithelial nature.
Polymorphism of the lymphoid background and immunohistochemical stains using keratin and leukocyte common antigen will help make the diagnosis.
The nuclear feature is closer to a lymphocyte, and the cells show lymphoid antigens, such as leukocyte common antigen
, CD20, and CD79.
The tumor was also studied by means of electron microscopy and immunohistochemical stains against keratins (human cytokeratin high-molecular-weight MO630, Dakopatts A/S, Glostrup, Denmark), epithelial membrane antigen (E29, Dako), leukocyte common antigen (2B11 +PD7/26, Dako), vimentin (V9, Dako), neuron-specific enolase (BBS/NC/VI-H14, Dako), synaptophysin (SY38, Dako), and chromogranin A (DAK-A3, Dako).
The tumor did not stain for leukocyte common antigen, showed weak cytoplasmic positivity for vimentin and epithelial membrane antigen, and displayed strong positivity for AE1-AE3, CAM 5.
5] The following antibodies were used: CD3, L26 (CD20), leukocyte common antigen
(CD45), CD45RA, CD79a, immunoglobulin (Is) [Kappa] and [Lambda] light chains, IgC, IsM, IsA, IgD, Bcl-2, VS38c, epithelial membrane antigen (Dako, Carpinteria, Calif), Leu-22 (CD43) (Becton-Dickinson, San Jose, Calif), UCHL1 (CD45RO) (Ventana Medical Systems, Tucson, Ariz), Bc-1/cyclin D1 (P2D11Fll, Novocastra/Vector, Burlingame, Calif), syndecan-1 (CD138) (MCA681, SeroTec, Raleigh, NC), and cytokeratin (AE1/AE3) (Boehringer Mannheim, Indianapolis, Ind).
5] The RS cells in nodular lymphocyte predominance Hodgkin disease (NLPHD) variant stain positive with antibodies to leukocyte common antigen
, L26, and pan-B-cell markers in contrast to the RS cells of other variants, which are Leu-M1 positive and nonreactive with pan-B-cell markers.