Malignant myopericytoma

Definition

A tumour showing the histological features of a myopericytoma along with malignant histological features.

Clinical features

These tumours may arise superficially or in deep locations in various anatomic sites. The patient may have a history of previous benign myopericytomas.

Macroscopic appearances

The tumours are poorly circumscribed.

Histopathology

There are myoid appearing oval or spindle cells with eosinophilic cytoplasm growing in a concentric perivascular pattern. Mitoses are frequent. There may be foci of necrosis.

Immunohistochemistry

 

SMA

5/51

 

Desmin

1/51

AE1/AE3

1/51

EMA

1/51

S-100

0/51

   
   
   
   
   

Differential diagnosis

All of the below lack a concentric perivascular growth pattern.

Prognosis

Four of five tumours pursued an aggressive course1.

References

1McMenamin, M. E. and C. D. Fletcher (2002). "Malignant myopericytoma: expanding the spectrum of tumours with myopericytic differentiation." Histopathology 41(5): 450-60.

 

This page last revised 12.1.2004.

©SMUHT/PW Bishop