Conversation: The conversation between human and AI assistant.
[|Human|] 31 yr old male. Wrestler and jiu jitsu practitioner. Never had any significant health problems. I found a quarter sized lump on my inner thigh a couple inches south of my groin. It is firm, painless, slightly purple with a black dot on the top. You can move it under the skin. Ive attempted to puncture it with a needle and squeezed it pretty hard to see if pus would come out. Only blood. I now have some fluid build up around the lump (what I get for being a DIY doctor, right?) It hasnt gotten any bigger. I started doing jiu jitsu again about 4 days a week for the last month. Only after I started jiu jitsu did this lump come up. Any ideas what it could be?
[|AI|]  Hi there - Lump on the thigh could be a number of things.  Given your history of Jim Jitsi and wrestling, the most common thing is a hematoma (old blood clot) under the skin.  Another cause could be a lipoma (basically, a benign fat ball).  Neither of these is cause for concern. Another more concerning cause could be an enlarged lymph node, which can be caused by a benign infection and in rare cases, malignancy (cancer). I certainly don't mean to scare you, and the other causes I mentioned are much, much more likely. I'd recommend you not stick any more needles in it for starters, and ask your doctor for an ultrasound. If there's any question, they can biopsy the mass and find out what it is. Hope this is helpful, feel free to contact me if you have any further questions.