<s>[INST] Hey I m a 16 year old boy and I m very healthy but there is a large bump on the top of my right foot next to the ankle and it is not painful except when I work out alot. My doctor didn t know what it was and my orthopedic surgeon did not know what it was so I m going to a specialist and I m scared. My doctor said there is muscle involved and there is an extremely small anomoly with the bone in the area and it is about half an inch in height and easily an inch in width on the surface. Please help and I m scared!! [/INST] Hi, Welcome with your query to Chat Doctor Virtual Clinic. Reviewed your query details. You seem to have a Ganglion Cyst of right Foot. Pain in this lump after heavy work out is due to the friction edema from friction inflammation with surround bony and tedious parts. This lump mostly is Histiocytoma and is a benign hamartomatous tumor arising from the synovial sheath of the small bone joints of the right foot. CT guided Arthroscopic Laser Ablation, is the latest and best treatment option currently, with the least recurrence. So don't worry about it being Cancer. And is very well treatable lump. This reply would help you to plan treatment with your doctor. Contact after 2 weeks time with a Followup Premium question to ME. Will appreciate your Hitting, thanks. Will appreciate review with your excellent review write up comments. Welcome with any other further query in this regard, if need be. Good Day!! Chat Doctor. S. Genl-CVTS </s>