ATLANTA, Georgia (CNN) -- Mark Windsor looks exhausted. For a week he's been undergoing radiation treatment on a cancerous tumor in his neck. A metal rod fused to his spine keeps his head stable. His muscles there are gone, the result of multiple failed surgeries to rid him of his disease. He can't turn his head sideways or look up or down. So his look stays fixed, despite his fatigue.

The radiation Mark Windsor is receiving will only prolong his life, not save it.

"If I probably had gotten some good treatment several years ago I probably would have been cured," Windsor said from his home in Atlanta, Georgia.

The reason he didn't get care sooner -- he couldn't afford it, because he didn't have insurance. Windsor, a self-employed photographer, has had bone cancer -- a rare chondrosarcoma -- for more than 25 years. At 52, that's almost half his life. While he's found help from a few generous doctors, his efforts to survive have often been desperate. And now he's learned, largely in vain.

"I've been given anywhere from 18 months to three years," Windsor said. "And of course that's if I continue to go through these brutal treatments that I don't know that my body is capable of doing anymore. I'm tired. I've had a lot of operations in my life. And this radiation treatment wasn't much better on it. It's now taken my ability for taste away. My smell is horrible. I feel nauseated every day. And I just don't think this ever had to get to this."

Windsor first asked for the radiation therapy 13 years ago, long before his cancer had advanced into the brutal disease that's now assailing him. If he had been treated anytime sooner, the therapy might have worked to eradicate his tumors, when they were still small. But without insurance, Windsor couldn't afford the proper surgeries and follow-up care needed for the radiation to be effective.

The American Cancer Society says uninsured patients are 60 percent more likely to die within five years of their diagnosis. Without insurance, the diagnosis is twice as likely to come in the later stages of cancer.

Just when Windsor's lack of insurance started killing him is difficult to say. His timeline is long. But Windsor points to a period in the fall of 2006.

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His cancer had returned. But this time, the surgeon who had donated his services was no longer on staff at the hospital where Windsor was on a charity plan. His lifesaving operation wouldn't be possible.

"All of a sudden I'm out here in this world with no hospital and no doctor. And everybody I faxed -- I got on my computer and sent out e-mails and faxes to at least 20 neurosurgeons in Atlanta and not a single one responded," Windsor said.

If Windsor were poor, he could've found insurance through Medicaid, but his $30,000 income was too much to qualify. So instead, he walked into an Atlanta emergency room.

"All they did for me ... was check my blood pressure and my temperature," Windsor recalls. "I said, 'This is not the answer.' "

Thirteen hours later, feeling frustrated, he left. A few months later, he found his answer: He got health insurance when he married his good friend, Val Chamberoam, who put him on her health policy.

By the time Windsor got to the operating room, in the summer of 2007, his tumor was so large that it covered his entire neck. It had been growing for 10 months.

"It's just never recovered," Windsor said. "It's gone from grade one to grade three, and also now has spread to my lungs."

Today, there's nothing more doctors can do. The radiation Windsor is receiving will only prolong his life, not save it.

And what about his wife, Val?

"We're going through a divorce," he said. "Because I have so many hospital bills now, insurance companies have denied to pay them...so I've done what I think is proper, filed for divorce, so that my wife is not stuck with my hospital bills."

For now, Windsor finds pleasure in the smiles of the people he photographs. As for his own, you never see it. His face is grim and angry.

"I'm angry at the greed of the insurance companies," Windsor said. "Everybody has the right to make profits. Every corporation has the right to be strong, make the right decisions. But I don't think that it is proper to deny people with chronic disease the opportunity to get well."

Windsor's sentiment is probably shared by many of the nearly 50 million Americans who have no health insurance.

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Karen Ignani, president and CEO of America's Health Insurance Plans, says the organization would like to see all Americans covered. "Anytime anyone falls through the cracks, this is a major societal, national problem. What we've done recently is our members have recognized that individuals who are not being sponsored by employers, don't have employer coverage or aren't eligible for public programs need additional help," Ignani said.

"We proposed a strategy that involves setting up risk pools at the state level and our members agreeing to backstop those risk pools by taking everyone who may not be able to be eligible."

In May, Windsor will begin government-sponsored disability insurance. He'll be covered for the remainder of his life, however short it may be E-mail to a friend

John Bonifield is an associate producer with CNN Medical News.

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