FRIDAY, Oct. 29 (HealthDay News) -- Canadian researchers say
they've noticed a disturbing trend: Cancer doctors ordering
unnecessary blood transfusions so that seriously ill patients can
qualify for drug trials.
In a letter published recently in the
New England Journal of Medicine, the researchers report on three cases during the last year in Toronto hospitals in which physicians ordered blood transfusions that could make the patients appear healthier for the sole purpose of getting them into clinical trials for chemotherapy drugs.
The practice raises both medical and ethical concerns, the
"On the physician side, you want to do the best for your patients," said co-author Dr. Jeannie Callum, director of transfusion medicine and tissue banks at Sunnybrook Health Sciences Centre in Toronto. "If these patients have no other options left to them, you want to do everything you can to get them into a clinical trial," she said.
"But the patient is put in a horrible position, which is, 'If you want in to the trial, you have to have the transfusion.' But the transfusion only carries risks to them," she added.
A particularly serious complication of blood transfusions is
transfusion-related acute lung injury, which occurs in about one in
5,000 transfusions and usually requires the patient to go on life
support, said Callum.
But besides the potential for physical harm, enrolling very sick
people in a clinical trial can also skew the study's results --
making the drug perform worse than it might in patients whose
disease was not as far along.
The unnecessary transfusions were discovered by the Toronto
Transfusion Collaboration, a consortium of six city hospitals
formed to carefully review all transfusions as a means of improving
patient safety, Callum said.
At this point, it's impossible to know how often transfusions
are ordered just to get patients into clinical trials, Callum said.
When she contacted colleagues around the world to find out if the
practice is widespread, all replied that they didn't scrutinize the
reasons for ordering blood transfusions and so would have no way of
Dr. J. Leonard Lichtenfeld, deputy chief medical officer of the
American Cancer Society, said he was not aware of physicians
manipulating eligibility for clinical trials through transfusions.
However, the letter raises a provocative issue that should be
studied further, he said.
"This is something I have never heard of, never seen and I can't say how common it is," Lichtenfeld said. "I believe the authors have brought a very important issue to the attention of the oncology community and our patients."
If found to be commonplace, Lichtenfeld said the practice should
stop. "Giving unnecessary transfusions is not the way we should be
increasing access to new cancer drugs," he said.
Another layer to the issue that should be examined, Callum said,
is how reasonable the "exclusion criteria" regarding participation
in clinical trials are in the first place. The exclusion factors
take into account a drug's toxicity and who is likely to be helped,
"Exclusion criteria" are meant to protect patients by keeping people out who are too ill to metabolize a drug effectively, or too fragile to handle its side effects.
But drug companies want positive results, Callum noted, so there
can be pressure to select healthier patients to make the drug look
If doctors are bypassing the exclusion criteria, it may be that
they believe the criteria are unfairly leaving some very sick
patients out of trials who could benefit, she said.
"We have to make sure exclusions are not selecting for the best patients that will make the drug look its best," Callum said.
Find out more about blood transfusions at the
U.S. National Heart, Lung, and Blood