The Staining Reactions of Chordoma

Abstract

Although chordoma is a rare tumour well over 300 cases have been reported, and the excellent published descriptions of both pathological and clinical features leave little to be added (Stewart, 1922; Cappell, 1928; Mabrey, 1935; Dahlin and MacCarty, 1952). The pathological diagnosis depends on the recognition of the physaliphorous or bubble-bearing cells which are the most striking feature of the histological picture. These cells (Fig. 1) often attain great size and usually occur in groups or cords with an epithelial pattern; they are distinguished by the presence of numerous clear vacuoles of varying size which are separated by faintly eosinophil cytoplasm, the cell having almost an aerated appearance. The groups of cells are separated by a matrix or ground substance which has a similar frothy vacuolated appearance to the cell cytoplasm. In some areas -mainly the older parts of the tumour-the cells collapse to nondescript stellate and fusiform varieties and are often separated quite widely by this frothy ground substance (Fig. 2). Biopsy from such an area presents considerable difficulty and has often led to an erroneous diagnosis of chondrosarcoma, especially when the tumour occurs in one of the less common sites such as a spinal vertebral body. In these circumstances some staining reaction which would distinguish between the ground substance of cartilage (more particularly neoplastic cartilage) and chordoma would be invaluable. The present paper presents from this point of view a study of material from six cases of chordoma.