instruction: hello doctor I have a black patch on my back which is almost circular and is itching constantly it has become quite big in the last three to four months can you please suggest what it could be and what I can do it feels good when I put hot water on it and it becomes very dry it has a small line on its edges the itching is happening continuously it subsides a bit when I apply moisturizer but the black patch seems to become darker
output: hi can you attach the picture of the lesion for an accurate diagnosis and treatment plan please attach a picture of it