(CNN) -- Thomas Sedowski saw the big white dot on his brain scan, but thought he'd gotten a lucky break when the doctor called it a "lesion."
Bruce Blount had to give up his U.S. Air Force position after being diagnosed with a rare form of brain tumor.
"I'm thinking, well that's not so bad, a lesion, you know, I thought that's like a sore or cut or something," he said. "Gosh, I thought I had cancer!"
But Sedowski, director of accounting at a university in Missouri, quickly learned that the dot was actually glioblastoma multiforme.
With his diagnosis in 1999, he entered the complicated, jargon-filled world of cancer, just as Sen. Edward Kennedy has this week.
People who have survived brain tumors emphasize that such diagnoses do not necessarily mean that death is around the corner.
"It used to be considered a death sentence, and it's not anymore," Sedowski said.
CNN.com asked readers to submit their stories of struggling with brain cancer. Dozens of users like Sedowski shared their experiences on iReport.com. Read more iReports of brain cancer survival.
At age 32, Teresa Seely of Liberty Lake, Washington, also received a diagnosis of glioblastoma multiforme, commonly called GBM, a type of tumor that represents about 23 percent of all cancers that start in the brain. She urges patients to learn as much as they can as fast as they can and not to be afraid to question doctors.
"I think it's important for every patient to take what they have and be their own advocate," she said, speaking from a hospital because she now has another form of cancer.
"Research things and demand to have their questions answered and just continue to be in charge, and don't just let their fate rest in the hands of doctors, some of whom feel that GBM is a death sentence," she said.
Seely, now 40, went through an arduous process of surgery, chemotherapy and other medications. She credits her recovery mostly to an experimental drug called Thalidomide, which she said many doctors are afraid to use because of its history of causing birth defects and because it's not FDA approved for cancer treatment.
Having difficulty communicating with doctors is a problem for patients with many kinds of cancer, said Sedowski, who participates in a support group. He says that among patients who have all kinds of cancer, he sees many other similarities, such as insurance difficulties.
The tumor affected Sedowski's right parietal lobe, which he said made it relatively more accessible for surgery than other locations might have.
"The thing with brain tumors is that it's just like real estate: location, location, location," he said.
Today, Sedowski, who lives in Jefferson City, Missouri, says he doesn't have any sign of an active tumor. He still takes anti-seizure medication every day.
Cancer can change many aspects of a life. Sedowski was able to continue working in the same occupation, but Bruce Blount of New Egypt, New Jersey, had been a technical sergeant in the U.S. Air Force for more than 13 years when he found out he had ependymoma, a rare kind of brain tumor, in 1995.
At 36, he thought he would die. He spent three months in the hospital, undergoing a craniotomy and radiation therapy, and battled blood clots, infections and pneumonia.
The surgeons removed more than 99 percent of the tumor. Though he wasn't qualified for his job after treatment, he didn't feel upset about retiring.
"All that wasn't too important anymore," he said. "I'd been through enough."
Blount runs an online support group with about 100 members worldwide who have his condition. The group is part of an organization called T.H.E. Brain Trust, which provides support for more than 2,000 people. He and Sedowksi urge other cancer patients to find a support group.
"There's nobody better to talk to than somebody who's been through it," Blount said.
He also emphasized that a seemingly dire diagnosis does not always mean death is imminent, and that a patient should seek the best brain tumor center possible for treatment.
"I didn't expect to live this long, but I have," he said.
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