It's Always Something

In preparing to introduce Delphi to the double bridle, and as a useful training tool we are using a kimberwick bit on Delphi:
Delphi goes wonderfully in the bit and I am learning to develop more feel. However, Delphi has an ~10 centimeter benign melanoma right under her chin:
So when the kimberwick chain is not in action, it rests directly on the tumor:
Under her veterinarian's orders, we are starting Delphi on oral cimetidine to reduce or hopefully eliminate the melanoma. There is always the option of surgical removal, but I strongly hesitate to create a wound where there is otherwise nothing open. We'll see what happens on the cimetidine.