M. Guarino et al., THE EXTRACELLULAR-MATRIX IN SARCOMATOID CARCINOMAS OF THE BREAST, Virchows Archiv. A. Pathological anatomy and histology, 423(2), 1993, pp. 131-136
The distribution of the main extracellular matrix components has been
investigated immunohistochemically in four cases of breast sarcomatoid
carcinomas. The histogenesis of these tumours is still unclear, but m
ost evidence suggests that the sarcomatous component originates from m
esenchymal conversion of carcinomatous cells. We found that carcinomat
ous portions of the tumours were associated with linear basement membr
ane-like deposition of laminin, type IV collagen and heparan sulphate
proteoglycan that partially circumscribed the epithelial nests. The sa
rcomatous components produced an extracellular matrix immunoreactive t
o fibronectin, type I, III and VI collagens and tenascin. However, in
two cases, in some sarcomatous areas, focal pericellular staining for
antibodies to laminin and type IV collagen was seen. These results ind
icate that modifications observed in the double tissue component of th
ese tumours involve not only the cell shape and the cytoskeleton, but
also the components of the extracellular matrix. The significance of t
hese findings and their relevance in the understanding of the phenotyp
ic pattern changes of these biphasic tumours are discussed.