the first three photos look like a patch of red skin similar to aform of dermatitis which look red / brown, or even dry patches of skin caused by the sun. But the 4th photo look like the area is indented due to acne scars and post inflammatory hyperpigmentation.
What caused that area to be discolored... did you have acne there in the patchy area before? Or did you apply anything on it that may have irritated it causing it to be discolored?
If it's red, press down on the skin - if it turns white, then it could be treated with a vascular laser such as vBeam. If it's brown in color, the BBL (broad band light) therapy might workbut on low settings for those of darker skin types. PicoSure, and Clear And Brilliant might also work if it is brown in color. IPL will work for brown discoloration marks but for light skinned individuals -for darker skin types IPL can make the discolorationworse. Hydroquinone cream can help lighten it up, but if what you have is dermatitis, hydroquinone can make things worse and redder. So I'd get it evaluated by a few dermatologists to get their opinions on what the condition is.