Mast cells and dendritic cells in basal cell carcinoma stroma

BACKGROUND. The interaction of tumors with the surrounding stroma has becom e an important topic in tumor biology. Basal cell carcinoma (BCC) stroma ha s been characterized as hypervascular and rich in mast cells. The presence of dermal dendrocytes thought to have both antigen presenting and wound hea ling functions has recently been reported in BCC stroma. GP1b-alpha is a ne wly described vascular adhesion molecule with potential significance in tum or biology. OBJECTIVE. TO further characterize the cellular phenotype of BCC stroma. METHODS. Eleven BCCs (8 nodular, 2 sclerosing, 1 adenoid-cystic) were exami ned using immunohistochemical techniques for the presence of antigens speci fic to vascular endothelium, mast cells, and dermal dendrocytes. RESULTS. The stroma of all BCCs demonstrated increased vascularity, increas ed numbers of mast cells, and increased numbers of dermal dendrocytes expre ssing both CD34 and GP1b-alpha adjacent to tumor nests. No differences: in antigen expression were observed between histologic subtypes of BCC. CONCLUSION. The close proximity of stromal mast cells and dermal dendrocyte s surrounding BCC nests suggests a biologically significant interaction. Th e pattern observed is similar to that observed in healing wounds.