I have an irregular shaped area on my right cheek....the skin is actually "indented". It appears  to have a VERY slight brownish color. However- I believe that it may only appear that way since it is lower the the rest of the area on my cheek. (Another odd thing is I can see it in the mirror- but can not feeling when rubbing my fingers over the area. The only thing I do notice when running my fingers over it is that the skin "folds".) It may be my imagination....but it appears to be indenting more and more. It's as if the subcutaneous fatty tissue underneath the epidermis is disappearing in this spot. I am 65 years old. I never had acne in my youth. I was raised in Florida though and was often exposed to the sun. By the way...this "indentation" is not scaly, does not itch, etc. Should I be concerned about this? All my research on the internet seems to say that this type of thing sometimes happens to HIV patients who are taking certain drugs. I am not an HIV patient. The only drug that I am taking is 100mcgs of thyroid medication each morning.