Trijntje,
Recently (about 3 weeks ago) one of my girls (2 year old Marshall's) had
surgery for several mammary tumors.  They were removed successfully,
along with her left adrenal tumor, but the lab results came back with
this info: "Left adrenal was not malignant.  Spleen is producing red
blood cells & is fine.  Abdominal mass was a poorly differentiated
carcinoma of the mammary gland & has the potential for local recurrence
and/or the possibility of metastisis to the local lymph glands and
elsewhere." The vet did an xray at my request to be sure that her lungs
were ok (they are), but told me that mammary tumors in ferrets are rare.
I recommend action as soon as possible.
[Posted in FML issue 4198]