AGOURA HILLS BOY SET FOR TRANSPLANT; CHILD TO GET BROTHER'S BLOOD TO FIGHT LEUKEMIA.

Byline: Kevin F. Sherry Daily News Staff Writer

On Wednesday, Keegan Doheney - a 5-year-old Agoura Hills boy suffering from leukemia - will receive a transplant of blood taken from his younger brother's umbilical cord and placenta 2-1/2 years ago.

The procedure is expected to help Keegan fight the leukemia that causes his infection-fighting white blood cells to go out of control and attack his oxygen-carrying red blood cells and blood-clotting platelets.

``We've kind of explained to him that he has a bad bug,'' said Wendy Doheney, Keegan's mother.

Keegan, who will spend the next several weeks under observation at Kaiser Foundation Hospital on Sunset Boulevard in Los Angeles, understands that his brother's blood will help him fight his disease, Doheney said.

Last week, Keegan, whose father is a pilot who serves as a lieutenant colonel with the Air National Guard, underwent three days of full-body radiation. Today will mark the last of four days of chemotherapy treatments.

The two procedures destroy Keegan's own bone marrow to make room for the transplanted cells.

Cord blood transplants have been performed for a decade now. Umbilical cords and placentas are a rich, concentrated source of stem cells, the building blocks of blood.

Such transplants typically involve one sibling donating to another, which greatly increases the process's chance of success and reduces complications.

When a child is born, doctors simply gather the small amount of blood from the cord and placenta and store it until it is needed by a sibling.

``You basically milk the placenta for blood,'' said Dr. Peter M. Falk, the co-director of the division of marrow transplantation at Kaiser.

In Keegan's case, doctors have about one ounce of material to work with, Falk said. The injection of the material should take no more than five minutes, he said.

``We'll thaw it out and infuse it quickly,'' Falk said.

Doctors diagnosed Keegan's leukemia when he was just 22 months old. His mother noticed that he bruised easily and that his attitude seemed to have changed.

``I just felt he wasn't being Keegan,'' she said.

After a month of radiation treatments, Keegan began a remission that lasted 3-1/2 years. Although Keegan was in remission when his brother, Keldan, was born in September 1995, ``mother's intuition'' led Doheney to ask doctors to save blood from Keldan's umbilical cord and placenta in case Keegan needed a transplant in the future.

Sure enough, last summer, Keegan's illness reasserted itself and once again attacked his body, Doheney said. Tests on the cord and placenta blood confirmed that the brothers were perfect matches.

The strain of Keegan's illness has taken its toll on the family, said Doheney.

``He stays a trooper through it all,'' she said. ``Mom's a little tired. . . . It's been an emotional battle but he gives me strength.''

Keegan decorated his hospital room with Dallas Cowboys paraphernalia for his extended stay, Doheney said.

``He's a big Cowboys fan,'' she said.

Keegan also spends his time playing with his Sega game system and watching videotapes.

If the cord blood transplant does not take, Keegan still can get a bone marrow transplant from Keldan, Falk said.

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2 Photos

PHOTO (1--Color in Conejo Edition only) Keegan Doheney, 5, of Agoura Hills, has been going through radiation and chemotherapy treatments to prepare for Wednesday's umbilical cord blood transplant.

(2--Color in Conejo Edition only) Keegan, who suffers from leukemia, does an art project Monday with his mom, Wendy, at Kaiser Foundation Hospital.

Tina Gerson/Daily News