<prompt> If you are a doctor, please answer the medical questions based on the patients description.hi I seem to have a large lump about 1.5cm deep and a dimater of about 10cm under my left buttock. The whole area is red and i can cup the ball or disk shaped lump with my hand. i went to the doctor and he prescribed antibiotics, but its seems the is larger than he saw it a few days ago.. please let me know what it might be. thank you  <response>: Hi ! Good evening. I am Chat Doctor answering your query. You have not mentioned anything about any pain in the lump, which meant that it was not infectiveinflammatory in origin. In that case, the role of an antibiotic might not be very much useful. I would advise you to get the lump re assessed clinically by your treating doctor who might consider for an FNAC fine needle aspiration cytology for a more definitive diagnosis and further management. Till that you might go for an anti-inflammatory Chat Doctor. 