Conversation: The conversation between human and AI assistant.
[|Human|] My 13 year old son has had a lump on the underside of the forearm.  We have been to the doctor twice and he said it is a ganglion cyst and if we wanted could see a surgeon.  He skin is becoming red and bruised and very discolored.  I looked up ganglion cysts and they usually form on or near a joint.  He is mid way on the under side of his left forearm.  What sould I do?
[|AI|]  Hello! Thank you for the query. Ganglion appears near a joint indeed as ganglion is connected with a joint and filled with joint fluid. He may have some benign skin lesion like a lipoma or sebaceous cyst. It is hard to tell from this point. However, there is a simple way to diagnose it. He should have an ultrasound of this lump which should answer what he is dealing with. Hope this will help. Regards.