(A) Case 1: lymph node with both CLL (10×/0.30 NA; B) and metastatic MCC (100×/1.40 NA oil objective; C) immunohistochemically stained (Dako EnVision+ Kit) with CM2B4,8 a mouse monoclonal antibody specific to MCV T antigen; and counterstained with hematoxylin. Case 2: MCC metastatic to lymph node showing strong nuclear expression of MCV T antigen expression (40×/0.75 NA; D) and CLL (40×/0.75 NA; E) demonstrating effacement of normal nodal architecture with a population of cells comprised predominantly of small lymphocytes with scant cytoplasm, round nuclei, and clumped chromatin. Images were acquired on an Olympus Provis AX70 using Spot 3.5.9 software for Mac OS (Diagnostic Instruments). All images were processed using Adobe Photoshop CS3. (F) Anti-MCV antibody levels (colored dots and triangles), as measured with MCV virus-like particle enzyme immunoassay (VLP EIA), are not significantly different in sera from CLL and ALL patients. Median MCV optical density values are indicated by horizontal lines, with bars representing interquartile values.
