Dedifferentiated chordoma : a case report

Abstract EN

Sarcomata's transformation (dedifferentiated chordae) in chordae is a very rare condition and has been emphasized as a distinct entity because of its more aggressive clinical course.

Here we describe a case of dedifferentiated chordae arising from the sacrococcygeal region of a 60-year-old man, in third tumor recurrence.

This tumor showed features of sarcoma with areas more typical of chordae The chordae-like areas expressed cytokeratin, epithelial membrane antigen and S-100 protein in all tumor cells and the spindle-cell component exhibited valentine positivity in all of them but negative for other markers.

The results showed that the sarcomata's areas as seen in the recurrent chordae lack epithelial cell features of chordae and suggest the possibility of altered differentiation pathway of the tumor stem cell or emergence of a new malignant cell population within the recurrent tumor.