A possible spindle cell sarcoma removed from the leg of a dog.  The mass was ulcerated and bleeding, which necessitated rapid removal.  The owners declined to send it to the lab for histopathology and definitive diagnosis, but when an in-house cytology was checked, suspicious spindle-shaped cells were seen.  Spindle cell sarcomas are typically locally aggressive, malignant cancers that can infiltrate deep into surrounding tissue on a microscopic level.  Their removal is often incomplete due to this aggressive behavior.  They tend to recur once removed unless radiation therapy is performed on the site.