When SCCA alliance partner Fred Hutch pioneered blood and marrow transplants — commonly known as bone marrow transplants or BMT — in the 1970s, they were exclusively for patients in their 30s or younger. The rationale was that the toxicities associated with the treatment were too much for older patients to handle.
Times have changed. Starting in the early 2000s, advances in blood and marrow transplants have made them less toxic and opened up the procedure to nearly everyone. This has saved and lengthened lives.
Dr. Mohamed Sorror, associate professor and physician at Seattle Cancer Care Alliance, is one of the leading advocates for more elder patients to have a blood and marrow transplant. He specializes in blood and marrow cell transplantation, as well as cellular therapies.

“I try to advocate for the idea that age is just a number,” Sorror says on a recent episode of the Oncology Sound Byte podcast. “What we've learned is there could be patients that are above 65, above 70, or even above 75 years old, who might do actually as good as younger patients or even better, because their biologic age...is actually young.”
What makes a patient fit for transplant? To help determine that, Sorror and his colleagues developed the Hematopoietic Cell Transplantation-specific Comorbidity Index (HCT-CI). Originally published in 2005, the HCT-CI tracks 17 comorbidities in a patient to help predict the likelihood of survival after a transplant.
“These numbers translate into risks and just tell the physician and the patient as well, ‘Here is the expectation from transplant based on your history, based on things that are related to your health,’” Sorror says. “Based on that model, you can tell a patient that, well, transplant seems to be really safe because the expectations are really good of that outcome.
“Or you can tell a different patient that we think transplant might be a risk, but we can do additional things to help you tolerate the transplant. Or you can tell another patient, maybe transplant actually is too much of a risk and other treatments could be better.”
Since the index was published, it’s become a key resource for doctors who are diagnosing and treating older patients.
“Developing that model...changed [medical] practice dramatically across the globe, because it has been adopted by transplant centers in many countries,” Sorror says. “Physicians use it regularly to evaluate risks of patients before they go to transplant. And because of that, now we have more confidence about what to expect when we offer a transplant to older patients.”
The HCT-CI continues to evolve. Sorror says he and his colleagues will soon add 12 more factors to the HCT-CI to help doctors and their patients assess the risks associated with blood and marrow transplant, specifically in those of age 60 years or older.
One of the more impactful factors that has emerged on the HCT-CI is gait speed — how fast a patient walks.
“Gait speed, which is one of the most effective objective tests to measure life expectancy, believe it or not,” Sorror says, “[We] can get a lot of information about life expectancy and about health.
“The comorbidity index comes almost hand in hand with gait speed because they cover two aspects of health. The comorbidity index asks the question about what other medical problems the patient has, while the gait speed is assessing the physical performance of a patient.”
In fact, both the HCT-CI and gait speed have become key aspects, together with older age, in identifying candidates for Sorror’s latest clinical trial, which explores novel interventions to minimize the suffering and prolong life after stem cell transplant. These interventions include:
- Supportive and palliative care;
- Clinical management of comorbidities through exercise, diet, and other methods, and;
- A combination of the two
“I do believe that palliative care support eventually could be a part of the standard of care, depending on the results of our trial,” Sorror says, “And I think if you use palliative care together with management of comorbidities, you might reach the best results.”
Initial results of the study could be published as early as 2022.
Listen to the full conversation via the media player below or your favorite podcast streaming service.
RadioMD with full transcription