I am a 44 year old Male. I found a lump about as large as a green bean in diameter and 1-2 inches long at the base of where my tailbone reaches my anus. It hurts when I sit. Other times I don't feel a thing. I am worried that it is cancer. I have had Hemorrhoid's my whole life and it's not a Hemorrhoid. Can anyone tell me what it really is? Should I see a Doctor?