### instruction:
If you are a doctor, please answer the medical questions based on the patient's description.

### input:
I have a hard lump on the top of my head, I have had it for 10 years and has not grown nor is it painful, it does not move and is hard, and is about the size of a euro coin maybe abit bigger, it doesn t sound like a sebocous cyst has it s rigid. can you tell me what you think, I am very worried?

### output:

Hi, Dear thanks for the query to Chat Doctor virtual clinic. I studied your query in full details updated from you. I understood your health concernsBased on your query data, In my opinion, Dear You seem to suffer from Desmond Cyst(epidermal/or teratatoid/or germinal) due to its site on top of head, or could be from Dermatofibrosarcoma Protuberance(DFSP)locally malignant tumor-needs to be ruled out- as your tumor is hard, it is known to recur and prognosis is bad with death in 2 yrs/ or it could be AMS(Atypical Mole Syndrome) with benign tumors of the scalp.FNAC Biopsy and CT of Skull to see the local invasion in the surrounding tissue is needed to find out the cause of this hard lump on the head, in your case. Team of GP doctor and Surgeon/ and Neurosurgeon for craniectomy if skull bone is involved, would be needed to treat your health issue. Hope this reply would help you to evaluate your case and treat it with your doctors in time to come. Hope this would resolve your query and worry and Anxiety accompanied by it. Welcome for any further query in this regard to ME. I would love to help you out.Awaiting any further query. Wish you fast recovery from this intriguing health problem. Have a Good Day. Chat Doctor. N.M.S. Genl-CVTS -Senior Surgical Consultant