With Provenge a patient has blood drawn, and their white blood cells are separated from their red blood cells. The white blood cells are shipped to a specialized lab, and treated with antibodies that "train" the white blood cells to attack cancer.
"It has a survival benefit over placebo from 3-4 months," said Penson. "You know people look at me and say you know 3-4 months you're not curing anybody... but for someone who'd have 18 more months to live, you get 20 percent more life."
Several more months of life might is not a considered "home run," but the method of treatment and the small step in a new direction has prostate cancer advocates and other cancer researchers excited.
"All of us want to see home runs -- but the reality is we don't have something like that," said Dr. Nina Bhardwaj, director of the Tumor Vaccine Program at New York University Langone Medical Center in New York City. "Even in cancer when new chemo drugs are coming out if you can improve survival by 4-6 months, it's a big step."
Bhardwaj was not part of the research team behind Provenge.
"For the people who did survive those few months longer, it's obviously significant for them," said Bhardwaj. "It does provide tantalizing clues that cell based therapies can achieve that which, we would ordinarily see with drugs. And if these are patients who've had all the drugs and haven't responded, it is exciting."
However, as Bhardwaj predicted, this type of treatment will be expensive. Patients have to pay for the expensive process of extracting the blood, the processing of the blood and the transport of all the samples.
"Being individualized therapy like that makes it expensive -- just like the bone marrow transplant," said Bhardwaj.
A spokesman from Dendreon, the company that makes Provenge said the company "has not yet set the price, however we expect it will be similar to other novel biologics that prolong survival."
Other "novel biologics" run between $50,000-$100,000 for a course of treatment.