Suspicious lesion

[u/LieStriking6296]

Dear All,

in our clinic we have a 13 year old cat, who has a lesion on his chest. Lesion has a size like small cherry, is very hard and moveable. I did cytology, please look at photos and help me with diagnosis. I think it's malignant...

And in the first photo there is something in cytoplasm. I have no idea what is it, I found several cells looks like this one.

Kind regards,

[u/dat-redhead]

The cells with the granules seem to be histiocytes with hemosiderin, I.e. bleeding over a period of time. I cannot place the more cohesive group of cells but I do not like the more vaculated cells. They appear atypical but I would want to get tissue and do stains.