A few weeks ago we has a dog present for enlarged scrotum. And indeed it was. While he definitely had a testicular tumor thing going on he also had a thickened scrotum. The base seemed pretty normal though so we scheduled a scrotal ablation neuter (where you remove the scrotum as well as the testicles).
Well, it was not so normal at the base after all. Whatever condition this dog had involved him developing a tremendous blood supply to the scrotum. I spend most of the surgery clamping and ligating vessels and stopping bleeding. Finally got it done though. Worst neuter I've ever done.
In this picture the bigger testicle is the one with cancer. The smaller is more normal looking but somewhat atrophied.
And here they are next to the rest of the scrotum-it was thickened and gelatinous. I've never seen this before. Owner declined biopsy so I don't know what was going on.
This dog is also super mean. So it was kind of a wasted effort, but still interesting.