Hello mam...  The information given is too less...  The cyst over the leg gives vast differential diagnosis.  If it's is an active inflammatory lesion or a benign non symptomatic swelling.  The active lesion might require an intervention,  so u can consult a surgeon.  If a swelling which has got to be removed,  aesthetically then u can consult a plastic surgeon.  U can text me online with a pic as well.