My older Yorkie ASTI (17yr) has lumbs every where. I have had some removed around her milk sacs. the vet seem to not worry about the rest of them... but her age might play a factor in that.
(sorry I forgot what the lumbs are called). If you think it is a lump not a bug or ect.. go to your vet ..but don't worry..ASTI has had these lumbs for a very long time and more keeps comeing..