CD99/MIC‐2 surface protein expression in breast carcinomas

Abstract

CD99/MIC-2 is expressed in breast carcinomas, especially in the matrix-producing variant of metaplastic carcinomas, which impairs its use as a marker to differentiate metaplastic carcinomas from primary and metastatic sarcomas of the breast. It seems to have no prognostic implications. However, phenotype similarities with other chondromyxoid tumours that also express the protein, like mesenchymal chondrosarcomas, suggest a relationship between MIC-2 reactivity and morphological differentiation.