Bump on inside of arm

a few years ago, a small bump came up on the inside of my right bicep. It started off small, and gradually grew over the years-it's not very big maybe a quarter inch in diameter. It does stick up off my arm a few cm.  It doesn't feel like it's got a root, it seems like i can pull the whole "knot" up-

[Gina04]

You should definitely have this looked at.  It sounds like it could be lymph node related.  It's possible that this could be a form of leukemia though if you don't have other symptoms it doesn't seem likely.  Also, breast cancer doesn't have to be in the breast itself.  The breast tissue extends over by the armpit.  My aunt had breast cancer that was found more in her arm area than her breast.  Most likely it is not a cancer thing but you should definitely have it checked out.