Extra-axial chordoma. Report of a case with immunohistochemical study.

A case of extra-axial chordoma arisen in the soft tissues of the posterior thoracic wall is reported. Immunohistochemistry showed coexpression of low molecular weight keratins, vimentin and S-100 protein in neoplastic cells. Although rare, examples of chordomas developing in extra-axial locations are reported in the literature and need be differentiated from other tumors that can mimic their histopathological features, such as myxoid chondrosarcomas.