The Arizona Republic
Experts comment on McCain move
Sen. John McCain’s decision to end treatment isn’t uncommon, one glioblastoma expert says.
Sen. John McCain’s decision to end treatment for glioblastoma is not uncommon for such an aggressive cancer.
If time is limited and the effect is minimal, it’s not worth it to continue treatment, said Dr. Michael Lawton, who is the president and CEO of Barrow Neurological Institute and an expert in glioblastoma, which has a median survival of 16 months.
“Doctors encourage patients to make their own choices when confronted with this disease, because it’s such a difficult disease to control,” Lawton said.
When people receive a diagnosis of glioblastoma, they are often very keen on doing everything possible to treat it, he said.
That typically involves surgery to remove as much of the tumor as possible, then a combination of radiotherapy plus chemotherapy to try and kill off or reduce the remaining cells that haven’t been removed surgically.
“They have a period of time where they can enjoy benefits of the treatment . ... Then they reach this point, where we are at now, where everything has reached the end of what can be achieved and they are failing terribly,” said Lawton, who is not involved in McCain’s treatment.
“Some will fight to the bitter end, and others will focus on quality of life. They’d rather have the best quality of days, rather than quantity of days.”
McCain’s family on Friday announced that McCain had decided to cease medical treatment 13 months after his diagnosis.
McCain, 81, underwent major surgery to remove a blood clot from behind his eye in July 2017, and it turned out to be related to a malignant brain tumor. He underwent chemotherapy and radiation treatment at the Mayo Clinic in Phoenix.
“Unfortunately, glioblastoma, the most prevalent malignant form of brain cancer, does not have a cure,” said David Arons, CEO of the National Brain Tumor Society. “Every patient is different and responds to treatment and responds to the disease differently. Stopping treatment is most often not a good sign. However, we don’t know Sen. McCain’s trajectory from here.”
Stopping treatment means the tumor’s growth will continue unchecked. At this point, patients can either be at home, with appropriate nursing care, or in a hospice, surrounded by health-care providers.
“It’s the most aggressive form of brain cancer. Typically surgery followed by chemotherapy, radiation and sometimes the use of what’s called tumortreating fields can stop the glioblastoma for a period of time,” Arons said. “But just about all glioblastomas come back. Often, when they come back, they come back stronger, and they’ve adapted to those first-line treatments.”
Unlike other cancers, glioblastoma is not usually painful when it goes untreated, Lawton said. But the tumor does slowly take away one’s mental capacity, which is difficult for both the patient and his or her family.
“The tumor keeps growing, and patients often have increasing levels of neurological deficits,” Lawton said. “In some ways, when people reach a point of entering hospice, it’s a recognition that they’ve come to peace with this horrible disease. And they can focus on their family and their goodbyes.”
Some patients’ tumors are more aggressive than others, and they don’t make it to 16 months, Lawton said. “I would have to interpret the events of today to mean that the senator has a more aggressive tumor that probably would not get him to 16 months,” he said.
Glioblastoma is the highest grade of glioma, and its most malignant form. Other high-profile people who have had glioblastoma include Sen. Edward Kennedy of Massachusetts; Beau Biden, the son of former Vice President Joe Biden; and Brittany Maynard, the California woman who started a national conversation about death with dignity.
Yet it’s a rare cancer, experts stress. Between 15,000 and 18,000 Americans are living with glioblastoma, and there are no specific risk factors, nor is there early detection or known prevention of the deadly disease, Arons said.
The five-year survival rate for a patient diagnosed with glioblastoma is less than 5 percent, said Michael Behrens, deputy director of the Translational Genomics Research Institute, or TGen, in downtown Phoenix.
Choosing to end medical treatment is in no way a capitulation to the disease, he said.
“I salute them for being transparent and courageous in how they are navigating the circumstance they are in,” Behrens said of the McCain family. “I’ve been so impressed by the legacy of Sen. John McCain, how he has not let the hardships of life define him.”
Survival statistics have not significantly improved over the past three decades. Yet Behrens says there is hope. In a recently published study conducted at Barrow Neurological Institute and initiated by TGen, for example, a drug called AZD1775 was shown to penetrate glioblastoma cells .
“When I was a young man entering brain-tumor research, the typical survival for a brain-tumor patient with these high-grade glioblastomas was on the order of 12 months. And now it’s around 16 months,” Behrens said.
“It’s about a 30 percent improvement. There’s also been improvement in quality of life . ... While it’s not the kind of progress we’ve seen for other, more common cancers, it is still moving in the right direction.”
Some “exceptional responders” are showing up in clinical trials, he said, citing CAR T-cell therapy, which uses an engineered immune cell from the patient to fight cancer.
“We have these instances where there are signals of good responses,” Behrens said. “They are not common, but if we can figure out how to match therapy to the patient’s individual tumor, that’s really what’s going to be what changes the outcome for patients with this terrible disease.”
Arons, of the National Brain Tumor Society, remains hopeful, too,
“When you think back to HIV in 1982, it was a terrible epidemic. Over time, with better science and better medicine, we were able to turn that into a chronic, manageable disease,” Arons said. “Not quite cured yet, but it is quite manageable. We’d like to see the same future for glioblastoma and for other brain tumors.”
“I salute them for being transparent and courageous in how they are navigating the circumstance they are in. I’ve been so impressed by the legacy of Sen. John McCain, how he has not let the hardships of life define him.” Michael Behrens
Deputy director, Translational Genomics Research Institute