Conversation: The conversation between human and AI assistant.
[|Human|] Hi! I have a small ( about the size of my figure tip ) hard immobile lump on my head. Sometimes it is very tender and other times its not. I have had it for years. I also have had CT scan 2 years for extreme migraines. The CT scan did not show anything out of the ordinary. Should I be concerned? If so what is the next step if CT scan didn t show anything?
[|AI|]  Hi, dear. I have gone through your question. I can understand your concern. You may have some inflamed cystic lesion like Desmond cyst or sebaceous cyst or some skin tumor.  They are not detected by ct scan.  You should go for fine needle aspiration cytology.  Then you should take treatment according to your diagnosis. Hope I have answered your question, if you have doubt then I will be happy to answer. Thanks for using Chat Doctor. Wish you a very good health.