ORANGE  (  —  Arizona Sen. John McCain is battling a rare but aggressive form of brain tumor called a glioblastoma.

CBS 2’s Michele Gile says remarkable progress is being made against this particular cancer at UC Irvine Health.

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While there are no approved vaccines for brain tumors, the hospital is testing four vaccines, as well as experimental drugs.

Pamela Berkson, a former UC Irvine Health nurse who had surgery on a glioblastoma 14 months ago, had the surgery at the same hospital where she worked.

UCI’s Daniela Bota is a specialist in the field.

“There is not any surgical procedure to remove the whole tumor out of the patient’s brain. This tumor is very infiltrative. This tumor tries to regrow and reform the brain,” says Bota.

But in Berkson’s case, the tumor hasn’t come back.

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In addition to radiation and chemotherapy, the Laguna Beach woman is taking an experimental intravenous drug offered to certain UCI cancer patients.

The drug is in phase 2 of a trial. Doctors say it is promising and they hope Berkson’s tumor will never grow.

“The first thing I wrote down,” says Berkson, “is time is precious. And then I wrote, it truly is and people don’t get it — until you’re maybe what I call ‘one of us.'”

In addition to UC Irvine Health drug trials which hope to help patients with this deadly brain cancer live longer, doctors are experimenting
with a vaccine for people whose tumors have come back. There are several promising treatments some of which are in phase 3 trials or completing phase three.

“This is like watching a horse race,” says Bota. “We know that one of those horses is going to cross the finish line. It’s going to happen. The most important thing that we can do is ask our patients to please  take part in clinical trails.”

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In almost every case, patients with glioblastomas see a recurrence of their tumor 6-7 months after their surgery.