PHOENIX (CBSNewYork/AP) — U.S. Sen. John McCain’s office says he’s had intestinal surgery needed to stem an infection and is in stable condition at a Phoenix hospital.

The longtime Republican senator has been undergoing physical therapy related to brain cancer treatment at his family home near Sedona, Arizona, since December. He previously said he was planning to return to Washington in January but has remained at home.

The senator’s office announced Monday that he had surgery the previous day at the Mayo Clinic.

“My father @SenJohnMcCain is in stable condition – he continues to inspire me everyday with his intense grit and determination,” daughter Meghan McCain said on Twitter.

Staff members for the 2008 GOP presidential candidate say the surgery was related to diverticulitis, a condition where the colon develops small bulges that can sometimes become infected.

McCain has had frequent visits from family, friends and Senate colleagues.

(© Copyright 2017 CBS Broadcasting Inc. All Rights Reserved. The Associated Press contributed to this report.)