My cairn terrier has a nasty cyst that is now the size of a large scallop or an Oreo cookie. It’s raw and bleeds. What can be done?

I cannot provide medical advice.

However, based on your comment where he is not healthy enough for surgery (I do geriatric rescue, and senior care and have done surgery on very old dogs before), I would ask to at least cauterize it.

I would also recommend a second opinion from a vet.

I can’t provide any medical advice.

I’d be inclined to attach an extra large gauze pad (maybe with 2 sided removable tape) to the inside of his shirt where the cyst is located. Hopefully, the gauze pad will prevent the shirt sticking, adhering, and continually opening up the wound. Usually, airflow helps promote healing, but you need to help prevent him scratching and rubbing at the itchy spot, so it can heal. Also, I’d make sure that the shirts are 100% cotton and loose fitting, which promotes breathability, and is a small percentage of all the dog clothes being sold. You could find 100% cotton apparel from a children’s store (human baby/kids department) & use hem tape (sewing&craft store) to achieve custom fit without sewing.