(NEW YORK) -- Wall Street billionaire Ted Forstmann is fighting for his life -- reportedly against the same virulent form of brain cancer that felled Sen. Edward Kennedy in 2009 -- and has reportedly told friends that his treatment was delayed by a doctor's misdiagnosis.
A spokesman for Forstmann's sports marketing company IMG, says only that Forstmann has a serious illness. But others, including Forstmann himself in an interview with The New York Times, call it brain cancer.
"Yes, it's brain cancer," someone familiar with Forstmann's condition told ABC News. "He was operated on to remove the tumor. He's undergone radiation and chemotherapy. The first phase of his treatment has had positive results."
Nonetheless, the prognosis for people with this type of tumor remains bleak. Kennedy died 15 months after his diagnosis.
About 9,000 people a year in the U.S. are diagnosed with Kennedy and Forstmann's type of cancer, a tumor called malignant glioma. Among people aged 15 to 44, such tumors are the second most common cause of cancer-related death.
"Glioma is a generic term," says Dr. John Ohlfest, associate professor of neurosurgery at the University of Minnesota. "It refers to a class of brain tumors of different types, some very aggressive."
Patients with the least aggressive type can live 10 years. Others like Kennedy, with the most aggressive type, called a glioblastoma, typically live no longer than 18 months.
Forstmann's chances for living even that long may have been compromised by his doctors' reported slowness to diagnose his condition correctly. According to Fox Business News, Forstmann has complained to friends that his doctors misdiagnosed his cancer for a year, thinking it was various illnesses, including meningitis.
Asked if Forstmann would take any recourse against his doctors, his spokesman said, "Ted has more important things to worry about at this point."
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