For years, transplants of bone marrow and peripheral stem cells have been the main options to treat leukemia and other ailments. But amid a declining number of donors, transplants of umbilical cord blood — rich with hematopoietic stem cells, which can be used as a source for producing blood — are starting to attract attention from doctors and patients.
Umbilical cord blood can only be extracted immediately after a mother gives birth. When a doctor cuts the umbilical cord, about 60 to 100 milliliters of blood can be extracted from the umbilical cord and placenta. The procedure does not inflict any pain on the mother or baby.
The blood is then sent to one of the six public umbilical cord blood banks in Japan — including one in Seto, Aichi Prefecture — then stored in a freezer and, later, infused into a patient.
At the Seto blood bank, 13 hospitals are registered, one of which is Hoshigaoka Maternity Hospital in Nagoya.
When an expectant mother gets a maternity checkup on the 10th month of pregnancy, Yuko Kondo, head of the hospital, and other doctors explain about the procedure and its benefits, and ask for their cooperation.
Haruna Sato, 30, who came for a checkup in mid-November, decided to donate her umbilical cord blood for the second time — having first made a donation when she gave birth to her daughter, two years ago.
“I thought it would be wonderful if I could save a life. I would definitely want mine to be used,” said Sato.
Tadayuki Ishimaru, 71, an obstetrician and gynecologist at the hospital, says about 60% of women who give birth at the hospital donate their umbilical cord blood, totaling some 300 people a year.
Hematopoietic stem cells can be extracted from donors of bone marrow and peripheral stem cells who are registered with the Japan Marrow Donor Program (JMDP). But the hurdles are higher for those donors compared with those for donors of umbilical cord blood.
Umbilical cord blood can be transplanted even when its HLA protein component — which indicates the type of white blood cells — is different, but it is harder to match donors with recipients for bone marrow and peripheral stem cell transplants.
Donors also need to go through multiple tests and be hospitalized to undergo transplants, which is time-consuming compared to use of umbilical cord blood. Donors have, in the past, turned down opportunities to participate in a transplant due to health, work and other reasons.
Donating umbilical cord blood has gained momentum since 1998 when the government started covering transplant procedures in its national health care program.
The number of transplants using such blood exceeded the number of transplants of bone marrow and peripheral stem cells coordinated through the JMDP in 2016, and in March the number of accumulated transplants from umbilical cord blood topped 20,000. The percentage of transplants to those who are not blood relatives is on the rise as well.
With the JMDP forced to cancel donor registration events amid the COVID-19 pandemic, more people are expected to rely on umbilical cord blood transplants in the future. The trend is already showing in figures.
In 2020, the number of transplants of bone marrow and peripheral stem cells coordinated through the JMDP was 1,092, down 151 from the year before. Meanwhile, the number of transplants using umbilical cord blood was 1,496 in 2020, up 117 cases from the previous year.
Yuki Fukushima, 42, a Nagoya resident who was diagnosed with acute myeloid leukemia about two years ago, was one of the patients who received an umbilical cord blood transplant. Even though she had a match with a donor at the JBDP, the donor withdrew their offer.
Thinking she may not be physically strong enough to wait for another donor, her doctor decided to look for an umbilical cord blood transplant opportunity in late October 2019. A month later, Fukushima had the transplant.
“At one time, I thought I would die, and not be able to see my child ever again,” said Fukushima.
At present, there are about 10,000 umbilical cord blood donations stored in the six banks nationwide. The more there are, the better the chances that a match from a donor can be found.
Fukushima, who returned to her workplace in the summer of 2020, hopes to raise awareness of the transplant method.
“I became well once again, thanks to a mother and a child somewhere in Japan.”
This section features topics and issues from the Chubu region covered by the Chunichi Shimbun. The original article was published Dec. 14.
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