Expression of Peripheral Node Addressins by Plasmacytic Plaque of Children, APACHE, TRAPP, and Primary Cutaneous Angioplasmacellular Hyperplasia.

High-endothelial venules are a common feature of 3 types of cutaneous pseudolymphomas: pretibial lymphoplasmacytic plaque (PLP) of children, acral pseudolymphomatous angiokeratoma of children (APACHE), and T-cell rich angiomatoid polypoid pseudolymphoma (TRAPP). In addition, primary cutaneous angioplasmacellular hyperplasia (PCAH) overlaps with these other 3 conditions. We intend to study the expression of peripheral node addressins in PLP, APACHE, TRAPP, and PCAH. We studied 1 case of PLP, 2 cases of APACHE, 2 cases of TRAPP, and 2 cases of PCAH. Immunostainings for MECA-79 and WT-1 were obtained in all cases. All cases showed a dense lymphohistiocytic dermal inflammatory infiltrate with a…