Two Maryland men, in a rarity, each gave blood platelets for the 100th time yesterday for cancer patients undergoing chemotherapy at the Johns Hopkins Oncology Center.
Allan Gillis, 47, of Glenelg, a Social Security Administration employee, and Brian Moreau, 40, of Millersville, a National Security Agency worker, made their donations with family, friends and center staffers nearby.
Mr. Gillis began giving in 1986, when his mother was diagnosed with leukemia. Mr. Moreau began in 1981 because a fellow NSA '' worker developed aplastic anemia, a disorder resulting in bone marrow failure.
"What has kept me going," Mr. Moreau said, "is knowing the products are going to be matched up and used fairly quickly."
He is also a volunteer fireman and trained as an emergency medical technician and in heavy rescue.
"Only one or two" Hopkins donors have given platelets as many as 100 times, and a Hopkins spokesman said that reaching that level was "very rare," and even more unusual for two donors to do so simultaneously.
Although the two men may have seen each other at Hopkins, they had never met before yesterday. This is unlike the two Internal Revenue Service auditors, Ellis A. Caplan and David J. Kovalic, who it was recently reported have given whole blood together for 18 years at the Greater Chesapeake and Potomac Red Cross Center.
Platelet donations differ in various ways from whole blood donations. Chemotherapy for cancer patients destroys cancer cells, but is also toxic to normal cells including platelets, the blood-clotting cells found in the bone marrow.
When the platelet level falls below the proper levels, the patients' lives may be threatened by excessive bleeding, bruising and other complications. Platelet donors supply the needed amounts, often on an emergency basis. Recipients get transfusions within 24 to 96 hours of the donations.
Platelet donors' blood is identified by HLA (human lymphocyte antigen) typing, giving individual signatures that allow donors to be matched with potential recipients.
If they want, donors may also be entered in the National Bone Marrow Registry. Donors may then be matched to help patients needing bone marrow transplants.
Platelet donors recline for almost two hours, rather than the eight to 10 minutes for whole blood. Blood is drawn from one arm, and the beer-colored platelets are separated out in a spinning machine and collected; the remaining blood is returned to the other arm.
Platelets can be given every two weeks or up to 24 times a year, while whole blood donors can give every two months or six times a year. Platelets have a shelf life of five days; whole blood lasts 42 days. Donors must be between 18 and 65; whole blood donors must be 17 and over. People who meet various health requirements can donate both ways.