Suggest Treatment For Circular Red Patch On The Legs

My husband is 44 years old, non-compliant Diabetic, smoker for 30 years, has HTN. I realize he is walking time bomb. But my question is that he has a circular red lesion on his leg, it has been there for several months and is getting larger. he also is developing more lesions on his other leg as well. They do not weep or hurt. What could this be?