ihad a colonoscopy 4 years ago had a few poyps removed, the dr said one was an adenoma, but didnt seem too concerned. Two weeks ago i ate cabbage which gave e severe diarreah , i battle with that alot, but after a sudden bout of diarreah, i noticed a hard lump on my anus that wont seem to go away. should i be concerned that it is another adenoma, it came on so sudenly.