Barring a last-minute cancellation, the bone-marrow transplant Utahns bought for a 6-year-old Orem cancer patient should be performed Thursday.

Jason Overman was scheduled to receive marrow from his sister Julie, 17, at the UCLA Medical Center Thursday afternoon."It's a relatively simple process," Vicki Beck, medical center spokesman, said Wednesday. "While the donor, Julie, is under general anesthesia, doctors will use a hypodermic needle to remove bone marrow from her hip. They will remove between 400 and 900 milliliters of marrow from Julie - about 10 percent of the amount she has.

"The marrow will be filtered through screens to remove fat and bone chips, then it will go to Jason through a needle in one of his veins."

Beck said the procedure would take two or three hours and would be no harder for Jason than a blood transfusion. Jason will be awake for the procedure.

Jason has spent the past week receiving massive amounts of radiation and chemotherapy to kill microscopic cancer and defective bone marrow, Beck said.

Doctors never use this extreme treatment unless a marrow transplant is imminent, she said, because without new marrow, a treated patient would die from infections within a few weeks.

Jason was diagnosed in February as suffering from neuroblastoma, a rare form of nerve cancer. When the Overmans' insurance company refused to pay for a bone marrow transplant - Jason's best chance for survival - the family turned to the community for help. Dozens of fund-raisers were sponsored by everyone from grade-school students to Utah State Prison inmates.

Their efforts raised $192,000. The bill for Jason's hospital stay is expected to be between $155,000 and $200,000, barring complications. Doctors' fees are not included in the estimate.

The transfusion should be easy, Beck said. The tricky part will be getting Jason safely through the following few weeks.

"The weeks after the procedure will be guarded," she said. "Some patients suffer serious infections or get pneumonia. Patients may require intensive care, blood transfusions and large dosages of antibiotics.

"And some patients suffer graft-vs.-host disease. The donor's marrow rejects the recipient's body and attacks it." Beck said this is the opposite of rejections common with organ transplants, where the recipient's body attacks the new organ.

"Thursday's procedure is nothing compared to what will come in the next few weeks," Beck said. The UCLA Medical Center staff has done more than 500 marrow transplants since 1973, she said.

Julie will remain in West Los Angeles for about a week after the painful procedure of donating marrow. Jason will stay in the medical center for six weeks to three months.

Jason is in good spirits, said his aunt, Lorraine Hill.

She said another aunt talked to him Monday "and said he sounded surprisingly good. He is still in good spirits. He said he was doing fine.

"Jon and Jane (Jason's parents) are very hopeful that everything will go well. We will all be glad when it's over. We hope the treatments and the transplant will send Jason's cancer into remission. There's not much we can do now but wait and see," Hill said.

She said the three Overman children not involved in the surgery returned to Utah Monday. The family has spent August in a small apartment near the medical center, using the time before the procedure for emotional bonding. The children who returned are staying with family members.

Jason was admitted to the medical center Aug. 1 and was released on Aug. 4 while doctors did tests that could be performed on an outpatient basis. He and Julie spent their common birthday, Aug. 5, playing in and near the ocean. He was readmitted Aug. 9.