PIONEER'S WORK BECOMES CONVENTIONAL Bone marrow doctor to retire

Now he can say it. Twenty-seven years ago, when Dr. George W. Santos was honing bone marrow transplantation into a lifesaving therapy for victims of blood diseases, the odds were so low, "You'd have to be out of your mind to try it."

But yesterday, this man with rumpled gray hair and a kindly grin looked across a room crowded with survivors -- 100 men, women and children who had been rescued from the threshold of death by a procedure that is now conventional.


"Who has the chance to be at the beginning of something and see all that's happened?" he said, looking supremely satisfied.

What brought the patients to Johns Hopkins Hospital yesterday was a ceremony marking the retirement of Dr. Santos, 66, who in June will give up full-time doctoring for a chance to investigate the mysteries of golf and boating.


Dr. Santos, who heads the bone marrow team at the Johns Hopkins Oncology Center, is regarded as one of the treatment's pioneers. Although not the first to attempt it, his team is credited with conquering some of the chief obstacles that initially kept survival rates so low.

Among its accomplishments, his group was the first to use the drug cyclosporine to combat Graft-vs.-Host disease, a potentially fatal affliction in which the transplanted marrow attacks the patient's tissues. The drug is now standard therapy.

In a development that would have been unthinkable a short time ago, Hopkins doctors are experimentally using another drug, thalidomide, to augment cyclosporine and improve survival rates.

Thalidomide gained notoriety in the early 1960s when women who took it to combat morning sickness gave birth to terribly deformed babies. But Dr. Georgia Vogelsang, who has spearheaded much of the thalidomide research at Hopkins, said it can be used safely in men and in women who are not pregnant, using effective birth control or past child-bearing age.

Today, patients with acute leukemia are given a 40 percent to 70 percent chance of living two years past their transplant, the point where relapses become rare.

No one was thinking medical cure when Dr. Santos was first exposed to the idea of a bone marrow transplant.

In the mid-1950s, he was serving military duty at the U.S. Naval Radiological Defense Laboratory in San Francisco, an installation set up to study the effects of atomic blasts on organisms.

Scientists discovered that high doses of radiation would destroy a mouse's bone marrow, ultimately killing the animal. Then came the breakthrough: Some of the mice could be saved if they received a transplant of bone marrow from a healthy mouse.


That discovery led scientists to speculate that a person with diseased bone marrow could be saved if the marrow were destroyed and replaced. Inspired, Dr. Santos returned to Johns Hopkins, where he had done his internship, and dedicated his career to the technique. Some 1,800 people have received marrow transplants at Johns Hopkins since the late 1960s.

The survival record at Hopkins is held by a patient who has lived 16 years after transplant. Yesterday, Nelson D. Zalva, a 43-year-old policeman from Tampa, Fla., could claim top honors among those in attendance.

Thirteen years ago, he began to lose weight, bruise easily and sweat profusely at night.

Hospitalized, he was diagnosed with leukemia. His cancer went into remission after a round of chemotherapy. But his oncologist said he probably would relapse and die if he didn't try a bone marrow transplant. Even that, he was told, offered him no better than a 50 percent chance of survival.

He was referred to Hopkins, where he endured the ordeal of additional chemotherapy to destroy his bone marrow. He lost his hair and fingernails, and the "chemo" produced "a total sickness you can't describe." The transplant itself, a transfusion of marrow into the bloodstream, was relatively painless.

He was the eighth person at Hopkins and the 16th in the United States to receive cyclosporine before a marrow transplant.


Graft-vs.-Host disease did attack his skin and kidneys, but he survived and was able to return to his job patrolling the streets of Tampa. Today he and his wife, Jeanne, remember Dr. Santos as a brilliant physician with the soft demeanor of Big Bird, a man who took four hours one day to explain the procedure and never looked down on anyone.