Meghan McCain on Tuesday gave an update on her father's health to a Phoenix radio station, saying a timetable has not been determined for her father return to the Senate.
"I wish I had an exact date, but I just don't," Meghan McCain told KTAR-FM. "I am very cautiously optimistic about the summer, yes."
The 81-year-old Arizona Republican has been battling a rare and aggressive form of brain cancer called glioblastoma. He was diagnosed last summer.
Meghan McCain said her father is doing well as he continues to undergo treatment.
"As everyone knows especially with this cancer, you have to take it scan by scan, but he is doing really good, much better than I think people anticipated," she said.
The six-term senator was hospitalized and treated for a viral infection in December. He has remained at his family's ranch near Sedona to undergo chemotherapy and physical therapy since mid-December.
"Anyone who has loved ones or has gone through it knows how horrific chemo is, and he's working through the side effects of it," Meghan McCain said. "He's doing very well, and I feel very lucky that he is doing so well."
The senator had initially expected to return to Washington in January, but was unable to do so. John McCain has not been giving interviews, but he has remained active on Twitter and has continued to issue written statements.
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