On Monday the White House website created a virtual condolence book so the public can send notes of sympathy to the family of Beau Biden. The vice president's son, who was 46, died Saturday of brain cancer -- a disease that kills more than 15,000 Americans every year.
Beau Biden suffered a mild stroke in 2010 and in 2013 underwent surgery to remove what was described as a small brain lesion, although the specifics are not public. The survival rates for brain cancer vary depending on the type of tumor.
Most malignant brain tumors in adults are glioblastomas which are highly aggressive. Treatment includes surgery, chemotherapy, and radiation, but the median survival is about 14 months and two-year survival is only 30 percent.
Clara Guy, 32, was diagnosed with a brain tumor when she was pregnant with her second daughter in 2012. A year after surgery, the cancer returned as an advanced glioblastoma. She said she was given six to 18 months to live.
"It felt like a punch in the stomach," said Clara.
In 2014, Clara was part of a clinical trial using immunotherapy at Duke University Medical Center. Since cancer often hides itself from the body's defense system, the strategy here is to manipulate immune cells to recognize and attack brain tumors.
"Once we rev up the immune system, the cells from the immune system can actually track the tumor down, even in these deep crevices within the brain and kill the cells in a very specific way without harming the cells around them," said Dr. John Sampson, a member of the medical team at Duke.
Finding cancer cells in those crevices within the brain is key, because a main reason for the poor prognosis is that by the time the diagnosis is made, the tumor cells have usually already spread microscopically beyond what's visible on a CT scan or MRI.
So far, Clara Guy is doing well.