PHOENIX (AP) — The daughter of U.S. Sen. John McCain of Arizona says the 80-year-old lawmaker has completed the first round of radiation and chemotherapy as he battles an aggressive form of brain cancer.

Meghan McCain also tweeted Friday afternoon that her father's "resilience & strength is incredible. Fight goes on, here's to small wins."

McCain, the Republican presidential nominee in 2008 and a six-term senator, was diagnosed last month with glioblastoma.

Doctors at the Mayo Clinic in Phoenix say they removed a blood clot above the senator's left eye and managed to remove all of the tumor that was visible on brain scans.

McCain says he expects to return to Washington next month.