Laminin matrix formation and S-100 protein and/or desmin-positive cells in malignant fibrous histiocytoma (MFH).

16/30 human storiform-pleomorphic malignant fibrous histiocytomas (MFH) showed a focal pericellular immunostaining for laminin. 14/16 of these laminin-positive tumours additionally revealed an atypical cellular differentiation (desmin- and/or S-100 protein-positive cells). The significance of focal laminin positivity along with atypical, non-entity specific differentiated cells is discussed before the background of laminin as being an indicator and promoter of differentiation in MFH. The limited value of a laminin detection in MFH for solving differential diagnostic questions (MFH versus other poorly differentiated sarcomas with basement membrane formation) has been pointed out.