Surgery - Circum-anal and tail tumours in a very old male dog

Gigantic circum-anal tumours - a type of surgery where fools go in where angels fear to tread as the dog is very old and the post-operation complications of not healing well are present.

Other than the very anaesthetic risks of operating on a very old dog, the other challenge is getting sufficient skin to stitch after excision of the gigantic circum-anal tumours.

Should this case just be rejected as being in-operable? I study the 3 images. In this type of high risk case, a short surgery of less than 15 minutes under just isoflurane anaesthesia is best for survival. Unfortunately, this will be at least one hour operation!

I got the dog on antibiotics and Tardak injection for 7 days first. Blood test showed high liver ALT and urea. To operate or not to? It is a very difficult decision for the owner.