Parachordoma, chordoma periphericum, chordoid sarcoma

Epidemiology

This is a rare soft tissue tumour. There has been dispute as to whether it exists as an entity, and whether it is identical to axial chordoma. or belong within the spectrum of the myoepithelioma group of tumours. Also extremely rare is the extra-axial skeletal chordoma.

Histopathology

Shows features of (a) extraskeletal myxoid chondrosarcoma, (b) chordoma and (c) chondroid syringoma.

Immunohistochemistry

 

AE1/AE3

2/22

  

MNF116

2/22

CK7

1/3 2

CK8

1/1 1

CK19

2/42, 1/1 1

CK20

2/3 2

EMA

1/1 1

S-100

4/4 2, 1/1 1

Brachyury

2/42

SMA

0/42, 0/11

GFAP

0/11
   

References

1 Karabela-Bouropoulou, V., Skourtas, C., Liapi-Avgeri, G., Mahaira, H..  A case report of a very rare soft tissue tumor.  Pathol Res Pract 1996;192:972-8.

2 Tirabosco Brachyury Expression in Extra-axial Skeletal and Soft Tissue Chordomas: A Marker that Distinguishes Chordoma From Mixed Tumor/Myoepithelioma/Parachordoma in Soft Tissue AJSP 2008;32:572

3 Advances in Anat Pathol 1997;4:256.

©SMUHT/PW Bishop