Young man grateful for experimental stem-cell lifeline

When Tyler Colosimo learned last winter that doctors could find no suitable bone-marrow donor worldwide to help save him from leukemia, he thought his days might be numbered.

His goal of becoming a filmmaker seemed to fade. So did his dream of returning to Japan, where he studied for a year. He wondered how his friends would spend their lives.

"I was pretty depressed. I thought a lot about what I had been able to do in life," said Colosimo, 22, of Spokane.

Then Colosimo learned that blood left over from the umbilical cords of two babies may have compatible stem cells that could help cure him.

The stem cells -- which are more commonly taken from bone marrow -- can produce healthy blood cells to replace the cancerous ones of leukemia.

What's more, Colosimo was told, new stem-cell technology at the Fred Hutchinson Cancer Research Center might further improve his odds.

"It was pretty amazing. I thought, 'How did you find that?' " said Colosimo, now recovering from a cord-blood stem-cell transplant he received May 24.

Colosimo was one of nearly 13,000 people a year in the U.S. who can't find a biologically matched bone-marrow donor. Siblings, other family members and 9 million people on donor registries worldwide can't help.

Minorities are disproportionately affected because stem-cell matches are linked to race, and the vast majority of bone-marrow donors are Caucasian.

Without the suitable cells, Colosimo would have had little hope of surviving the acute myelogenous leukemia that threatens him. Stem-cell transplants also can treat other types of leukemia, certain kinds of anemia and other potentially fatal diseases.

Transplants of stem cells from umbilical-cord blood have been around for nearly 20 years, and they work well in children who can't find an optimal match.

In such transplants, the patient's blood cells -- including the diseased ones -- are first killed off by radiation and chemotherapy, then the donated stem cells are transplanted and begin producing new cells.

The cord-blood stem cells don't have to match the recipient's tissue as well as those from bone marrow. And the blood is readily available from 45 cord-blood banks around the world.

But adults are bigger, and they need far more stem cells than children to quickly replace those killed off by the procedure. That includes white cells to protect against infections and disease.

As a result, adults are vulnerable to potentially fatal infections for about 25 days after such a transplant, while the cells reproduce and build a new immune system.

Tackling problem

Now, Dr. Colleen Delaney, a Hutchinson Center oncologist and researcher, thinks she may have found a way around the problem. Before transplant, the cord-blood stem cells are placed in a special culture that stimulates them to reproduce quickly.

The technique draws on the research of Dr. Irwin Bernstein, a Hutchinson Center pioneer in learning how stem cells develop.

Delaney has expanded the number of blood stem cells 150-fold in just 17 days. That reduces to 15 days the amount of time a patient is most vulnerable to infection. Scientists at other institutions have tried similar technology but increased the cells only fourfold.

"This can open up a whole new donor pool for people who can't find donors," Delaney said.

Colosimo is only the third patient to have the experimental treatment. A 42-year-old San Francisco man has fared well since his transplant a year ago, though he now is battling a viral infection. And six months after treatment a 30-year-old woman is healthy.

The treatment is only in its first phase of research, to make sure it is safe. This phase will involve about 12 more patients over the next two years. If the treatment goes well, another trial involving many more patients and other medical centers will follow.

"It's very early in the research now," Delaney said. "We have to have more patients to see where this is going."

As with all leukemia patients, Colosimo has had a rough six months since he was diagnosed in November.

His early symptoms -- terrific aching in his back, legs, even wrists -- were perplexing, especially since he was physically active with karate, rowing and other sports. While test results were pending, he developed fevers and difficulty breathing. The leukemia diagnosis came two days after Thanksgiving.

Colosimo soon started chemotherapy to put his leukemia in remission, so he could receive the transplant. And the months of unsuccessful searching began for a bone-marrow donor. In the end, not even his brother was a suitable match.

The network of cord-blood banks were a welcome alternative. Patients have a 95 percent chance of finding a donor. His doctors had the luxury of simply looking for the very best donors.

Difficult preparation

Colosimo was ready when two were found for the double dose of stem cells he would receive. "I got pretty excited, when Dr. Delaney told me," he said.

Colosimo then went through the harsh treatment in preparation for the transplant.

Chemotherapy and total body radiation destroyed all his blood cells, including the cancerous ones, to make room for the new, healthy cells. Side effects included nausea and exhaustion.

On transplant day, May 24, Colosimo's parents, Lynn and Tom, and brother Ben gathered in his hospital room. A bag of stem cells in solution, deep red in color, dripped into Colosimo's body.

"We really looked forward to that Day Zero, as they called it," said Lynn Colosimo. "Now we count the days since the transplant."

After the transplant, Colosimo had more rough days. He developed mouth sores and terrible fevers. Diarrhea and headaches racked his body for two weeks.

But on June 14, he was able to leave the hospital to continue his three months of initial recovery in a South Lake Union apartment near the Hutchinson Center and the Seattle Cancer Care Alliance, where he receives outpatient tests and treatment.

He's exhausted now, but if all goes well, he will recover fully in about a year. Then, he can resume his senior year at the University of Idaho in fall 2008.

He hopes to travel and perhaps work in Japan. He looks forward to building a career in filmmaking.

"So far, I'm happy with the treatment," he said. "It seems like it's working."

Warren King: 206-464-2247 or wking@seattletimes.com