Conversation: The conversation between human and AI assistant.
[|Human|] I recently discovered a large, none painful lump in my lower back. It can not be seen just by looking at my back but if you put enough pressure, you can feel it. It is about an inch wide and is shaped slightly like an oval. It moves under my skin and i suspect it is a lipoma. I do, sometimes, feel like a nerve is being pinched and it feels like the pain spreads down to my lower thigh. The only think that is making me thing that it is not a lipoma is that is is hard all around. Can lipomas be hard or are they always soft?
[|AI|]  Thanks for your question on Chat Doctor. Lipomas are always soft as it contains fat tissue only. So if you are feeling hard sweller than lipoma is unlikely. The site you are describing is also unlikely for lipoma. Lipomas tend to occur more in flexor surface of forearm, upper back etc. In my opinion you are having benign tumor of nervous sheath (Neurofibroma). It is hard, mobile and benign tumor. And it is on the nerve so when you press it, you can feel pain on area supplied by the nerve, same in your case. So Neurofibroma is more likely. But clinical examination and ultrasound is needed.