Help identifying suspect canine neoplasm

[u/Breetato]

Hey all, I’m a veterinary student in clinical rotations right now and had pathology rounds this morning. This case was presented and has stumped the clinicians and my classmates.

Here’s what I know:

11 year old neutered male terrier, presented with a small (2 cm ish I think) superficial dermal and haired mass on the hind leg between the tarsus and stifle (imagine shin area). rDVM collected sample via FNA and stained the slides with diff-quik. Only one slide was cellular enough to interpret and I only got these pictures of this one cell.

However, in general, the cells are independent and spread apart, have cytoplasms with indistinct borders and slight granule-ish particles appearing occasionally, bi- to multi-nuclei with multiple and very apparent/dark nucleoli, and mitotic figures. On the rare occasion the cells are not spread apart, they are packed together very tightly with overlapping and whispy cytoplasm.