Metastases to the breast - rhabdomyosarcoma


Procedure: Ultrasound-guided Tru-cut biopsy of the right breast nodule.

Diagnosis: Metastatic embryonal rhabdomyosarcoma.  

The immunostain with the antibody anti-CD45 is negative, desmin is +++, CD99 focally positive.  Synaptophysin is negative and Ki67 is very high (>70%). The positivity of desmin is consistent with the diagnosis of rhabdomyosarcoma (embryonal).

Ascitic fluid analysis was also positive for metastatic rhabdomyosarcoma.