Demonstration of fibronectin in soft tissue tumours using the immunoperoxidase technique.

A variety of reactive, benign and malignant soft tissue lesions have been stained for fibronectin using the immunoperoxidase technique. Two patterns of mesenchymal staining have emerged. The first has a diffuse stromal collagen and basement membrane distribution within normal and neoplastic mesenchyme and the second a more specific intracytoplasmic granular staining pattern. The latter is seen only in lesions derived from fibrous-histiocytic and synovial cells, a finding which may be of diagnostic use. The possible significance of intracellular fibronectin in neoplastic mesenchyme is discussed.