LINCOLN, Neb. (AP) — A spokeswoman for Nebraska Attorney General Jon Bruning says Bruning has successfully undergone surgery to remove part of his colon and surrounding lymph nodes.

Bruning disclosed Wednesday that he has been diagnosed with colon cancer, but he said he was optimistic that Thursday’s surgery would remove the cancer.

Bruning’s office said late Thursday that doctors will not know whether the disease had spread until test results come back next week. Bruning remains hospitalized in Lincoln.

Bruning has said he believes the cancer was caught early.