These can occur anywhere along the spine, but in ferrets, they most
commonly occur at the tip of the tail. Chordomas are considered
potentially malignant, however, metastasis has not been seen in these
neoplasms arising in the tail.

These should be removed for a number of reasons. Tumors of the bone can
be painful, there's increased risk of injury to the tail simply because
of the large knot on the end and it would be terrible if your ferret
was the one case where it was malignant and metastasis occurred.
Amputation of the necessary segments of the tail is curative and the
ferret will be happier with a tail that is a bit shorter but without
the tumor.

Ref: http://miamiferret.org/faq.htm#chordoma

We had a 4-year-old female ferret with a chordoma at the end of her
tail. It was just a small ball, barely visible, but you could feel it.
It was slow growing, and you could tell it was painful as she would
always keep her tail elevated. Since it was so small when it was
removed, she only needed about an inch of tail amputated. Surgery was
early in the morning, and by 5pm she was ready to come home. You could
tell it was a relief to her to have it gone. She was a brat that night,
climbing all over - you couldn't tell, other than the shaved portion of
tail with stitches at the end, that she just had surgery that day. She
had pain management for a couple days, and had a quick recovery. Her
tail fully furred again with the next shed.

Hope this helps.

[Posted in FML 7315]