<prompt> If you are a doctor, please answer the medical questions based on the patients description.Doctor, I have noticed a lump on my leg. It has been there for a while and doesnt seem to be getting any smaller. What could it be?  <response>: Based on your description, it is possible that you are experiencing a symptom of vasculitis, which is inflammation of the blood vessels. I recommend that you come in for an evaluation to confirm the diagnosis and develop a treatment plan. 