Question about swollen areas on an Elm tree

[Mikey]

We have a 32 year old Elm tree in the back yard (My father planted it when I was very young) that is huge and looks healthy for the most part. Since it's leaves have started to fall, I noticed one of the larger branches is swollen in an area where a smaller branch is growing out from it. It almost has a football shape to it. I did do some pruning in July and one of the smaller branches I removed had the same problem (?). I know Elms have a tendency to be sickly, I was curious if anyone knows if this is normal or should be removed. I know this isn't a prized tree, but it is quite nice and large and provides a good bit of shade.

[The Ent]

If it worries you, it might be worth pruning, if for no other reason than to remove a potential weak spot that might break later at an inopportune moment.