Syndecan-1 expression in different soft tissue tumours.

BACKGROUND

In vitro studies have suggested that expression of syndecan-1 (CD138) is correlated with morphologic phenotype (epithelioid or spindle) of cultured tumour cells.

MATERIALS AND

METHODS

Fifty-seven different soft tissue tumours were selected to analyse their syndecan-1 (CD138) reactivity. Immunohistochemical staining of paraffin sections, following a high temperature unmasking technique, was performed. The intensity and the pattern of staining was studied.

RESULTS

Cell membrane positivity was observed in epithelioid sarcomas and epithelial elements of synovial sarcomas. GISTs, some malignant epithelioid schwannoma and some fibromatosis showed intracytoplasmatic reaction, while pyogenic granuloma, Kaposi's sarcoma, fibrosarcoma and dermatofibrosarcoma protuberans were negative.

CONCLUSION

At first it seemed that the cell membrane positivity of syndecan-1 accompanied true epithelial differentiation in soft tissue sarcomas, but the results further highlighted the non specific nature of this expression. Therefore the heterogeneity in the appearance of syndecan-1 in various soft tissue tumours is not simply associated with the phenotype, suggesting more complex functions.