Sen. McCain's brain tumor diagnosis highlights push for a cure

Sen. McCain's brain tumor diagnosis highlights push for a cure

Sen. John McCain's diagnosis of glioblastoma Wednesday night once again sheds light on this devastating illness and the need to find a cure. It is the same brain cancer that took the life of Joe Biden's 46-year-old son, Beau, back in 2015, and former Sen. Ted Kennedy in 2009.

In a tweet by the former vice president, Biden showed his support, saying "… He is strong — and he will beat this."

Biden is currently spearheading the National Cancer Moonshot initiative , a new nationwide effort to end cancer. Its mission: to achieve a decades' worth of progress in five years in the prevention, diagnosis and treatment of cancer. The initiative is in response to a call to action from President Barack Obama in his final State of the Union Address.

Daunting statistics

Sen. McCain's brain cancer was determined after he underwent surgery to remove a blood clot over his left eye at the Mayo Clinic Hospital in Phoenix on Friday. Lab results determined there was a link between the clot and the tumor.

Glioblastoma multiforme is the most common and deadliest of the glial tumors because the cells reproduce so rapidly. They can be found anywhere in the brain or spinal cord. The tumor grows by turning normal brain cells into stem cells, which continuously replicate and regrow. So even if a tumor is surgically removed, it is difficult to extract every cancerous cell; any left behind will result in the growth of a new tumor.

According to the American Brain Tumor Association, there are nearly 700,000 people in the United States living with a primary brain and central nervous system tumor. Of these, 14.9 percent are glioblastomas. Glioblastoma has the highest number of cases of all malignant tumors, with an estimated 12,390 new cases predicted in 2017.

Since 1985, there have been only four FDA-approved drugs to treat the more than 120 different types of brain tumors, according to the National Brain Tumor Society. Between 1998 and 2014, claims the NBTS, 78 investigational brain tumor drugs were entered into the clinical trial evaluation process, and 75 of them failed.

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Traditional therapies for brain cancer — surgery, chemotherapy and radiation — haven't been very successful, says Dr. José Baselga, chief medical officer and physician-in-chief at Memorial Sloan Kettering Cancer Center, because the brain is designed so toxins can't infiltrate it. "It is very challenging to have chemotherapy get to the brain with a good dose," he said. Instead, Dr. Baselga says researchers and scientists are making strides in what he calls precision medicine.

Jill and Mazen Kamen, founders of the Kamen Brain Tumor Foundation, a nonprofit organization dedicated to funding cutting-edge research to find better and safer treatment options for pediatric brain tumors, are committed to the promise of precision medicine. They understand firsthand the challenge Sen. McCain is facing: In 2016 their 19-year-old son lost his own battle with glioblastoma.

Their foundation recently provided funding to the Dana-Farber Cancer Institute to continue its research on immunotherapy — testing chemotherapy agents in the lab beforehand to see if they can cross the blood-brain barrier.

"In the past, there was no way of knowing for sure which agents could cross the blood-brain barrier and which ones could not. Now they can see which ones will infiltrate the tumor in the hope of killing it," said Mazen.

The Kamen Brain Tumor Foundation also recently funded Memorial Sloane Kettering Cancer Center's research on intrathecal radioimmunotherapy, in which immune drugs are tagged with radiation and are inserted directly into the fluid surrounding the brain and spinal cord to kill the tumors.

"We were very saddened to hear that Sen. McCain, who has done so much for his country and devoted his life to public service, is fighting this disease," said Mazen. "Coming public about his illness is a great thing, because it sheds light on how devastating this disease is. And hopefully it will invigorate more federal and private funding to this cause."



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