title: Chordoma with a massive spindle-cell sarcomatous transformation. A light- and electron-microscopic and immunohistological study.
abstract: A 26-year-old woman was operated on for a bulky tumor in the sacral region; she died of massive local tumor recurrence and pulmonary metastases 3 months later. Most of the original tumor showed a highly cellular spindle-cell sarcoma compatible with a fibrosarcoma of a high grade of malignancy. In a few small areas of the tumor, a chordoma-like pattern surrounded by growth of spindle-cell sarcoma was found. The spindle-cell component exhibited vimentin positivity in all tumor cells, but many cells were also cytokeratin-positive. The chordoma-like areas showed cytokeratin in all tumor cells. The chordoma-like areas, but not the spindle-cell areas also were positive for epithelial membrane antigen and S-100 protein. This case indicates that the sarcomatous change associated with chordoma may contain keratins as a sign of epithelial differentiation, and may thus represent sarcomatous transformation of chordoma cells, rather than a coincidental soft-tissue sarcoma or collision tumor.
mesh_terms: D000328:Adult; D002817:Chordoma / Q000032:analysis / Q000473:pathology*; D005260:Female; D005354:Fibrosarcoma / Q000473:pathology; D006801:Humans; D007633:Keratins / Q000032:analysis; D008175:Lung Neoplasms / Q000556:secondary; D008565:Membrane Proteins / Q000032:analysis; D018396:Mucin-1; D010386:Pelvic Neoplasms / Q000032:analysis*; D009418:S100 Proteins / Q000032:analysis; D012445:Sacrococcygeal Region; D012509:Sarcoma / Q000032:analysis / Q000473:pathology*; D014746:Vimentin / Q000032:analysis
chemical_list: D008565:Membrane Proteins; D018396:Mucin-1; D009418:S100 Proteins; D014746:Vimentin; D007633:Keratins