Can I replace just the lug studs on the front of my 99 Saturn SL, or must I replace the wheel bearing hub?

All four lug studs have been broken. Long story. Can I just replace the lug studs, or are they an integral part of the wheel bearing hub, making it necessary to replace the hub in order to replace the lug studs? If the lug studs can be replaced, how do I get the old ones out of the hub? Thanks in advance!