Hi, I Just Wanted To Ask Regarding The Swelling Of

Hi, i just wanted to ask regarding the swelling of the right portion of my fathers buttocks coz i'm so much worried for him. The day i saw him i was amazed & fear/worried for what had happen to him then i tried to touched his right cheek of his buttocks and i feel its hard to touch while the other side os soft. Then I ask him whether he feels pain or something but he replies to me that he doesn't feel any pain at all its just the left cheek of his but is getting bigger compaired to the other side. May i ask from any of you on how or what is the remedy for this kinda thing? Thanks a lot & God Bless