11.5243
 

 
Boy,   2 years   3 months
 
Clinic: Progressive    abdominal  swelling.
 
Intraoperative:  20 x 20 x 15 cm     firm,  well-capsulated  mass  in the left half of   retroperitoneum. No  evidence of    gross  infiltration.
 
Problem: Is  this  a  malignant tumor ?-   and  origin ?
 
There  is  capular invasion  (Images  "border"),  there is  necrosis,   but  there  are    few  mitotic  figures (<1/10HPF), and  overall  the  cells  are not  highly  atypical (no  nucleoli).  Thanks !

asif45 2011-11-24 19:23	Any attachment with the kidney on radiology? My differential would be clear cell sarcoma of Kidney.   A. Loya
kunze 2011-11-24 19:48	That's in my view a well demarcated, partially necrotic malignant mesenchymal tumor with a predominant spindle cell morphology. The d/d includes a rhabdomyosarcoma of embryonal type, MPNST and a synovial sarcoma. I favor a MPNST with a heterologous rhabdomyosarcomatous and glandular differentiation. Immunostains for S100, CD56, desmin, myogenin and EMA or CK are indicated, as far as available.
jakob 2011-11-25 05:02	There is no known attachment to the kidney. Thanks to Both !