A 21-year-old patient consulted a dental surgeon about a tumour-like formation on the left cheek. The patient noticed the swelling for the first time a year ago. Objectively: on the left cheek skin there is a painless roundish pedunculated tumour up to 0,5 cm in diameter. The surface of the formation looks like cauliflower, the surrounding skin is not changed. What is the most likely diagnosis?