Hi, Could you please advise the best remedy to rid my cactus of it's rust spots. I was away for quite a while and came home to an infected plant. Thank you for your time.

Welcome to the site!

Moving the question to the cactus and succulents forum.

Bumping this thread to see if anyone has answers ... because I do not. I do not recognize the problem. The only thing I can add is that your plant is a Euphorbia, not a cactus, and if you do end up doing any pruning, be careful not to touch the sap that oozes out under pressure.

Thank you for your reply I appreciate it. I have been told they are rust scabs from a fungus?? Thanks again.

I really don't know. Hopefully someone else here recognizes this and responds. When in doubt with a diseased plant, you can try removing the affected parts, assuming that most of the plant looks okay. This is not a substitute for proper treatment, but it can be pretty effective if you catch the process early on. Just be real careful not to touch the Euphorbia sap, and clean your tools right after use, because it will harden into a crust on them.