Black lump on bunny back

Question
About a month ago, Cookie developed a lump around his shoulder blade.  The Vet did an aspiration and put him on antibiotics.  The results of this test were inconclusive, but they were leaning towards Basil Cell.  There is no hair around the lump (about 1.5" in diameter) and the lump has turned black.  The vet thought this was due to bruising from the aspiration, however the blackness has only increased in size and darkness.  There area now looks like black velvet.  He has a renewed zest for life now, but I can see in his eyes that he is not OK.  What is your opinion?

Answer
Dear Carie,

Is there fur growing on the lesion?  I can't see the lump to make an educated guess, but if this were my rabbit I would want the lump biopsied and sent to a lab for histopathology.

Basal cell carcinoma is generally not pigmented, but if it started out unpigmented, then the vet may be right about the bruising.  A pigmented malignancy on the skin is most often a melanoma.

It might be wisest to completely excise the lesion with good margins before it spreads any further.  Sometimes this will effect a cure.  And that way, the entire lesion can be analyzed by a good histopathology lab.

Hope this helps.

Dana